What is the femoral nerve stretch test?
The femoral nerve stretch test or the prone knee bending test is done for testing the motor function of the femoral nerve and to stress the lumbar (L2-L4) nerve roots. This is one of the most reliable techniques for assessment of the mid-lumbar (L2, L3, and L4) nerve root impingement.
What is Lateral Medullary Syndrome?
The lateral medullary syndrome (or Wallenberg’s syndrome, after the neurologist who described it in 1895) results from damage (usually infarction) of the posterolateral medulla with or without involvement of the inferior cerebellum, producing the following clinical features:
• Nausea, vomiting, vertigo, oscillopsia (involvement of vestibular nuclei);
• Contralateral hypoalgesia, thermoanaesthesia (spinothalamic tract);
• Ipsilateral facial hypoalgesia, thermoanaesthesia, + facial pain (trigeminal
spinal nucleus and tract);
• Horner’s syndrome (descending sympathetic tract), +/− ipsilateral hypohidrosis of the body;
• Ipsilateral ataxia of limbs (olivocerebellar/spinocerebellar fibres, inferior
cerebellum);
• Dysphagia, dysphonia, impaired gag reflex;
What is the cause of Lateral Medullary Syndrome?
Infarction due to vertebral artery occlusion (occasionally posterior inferior
cerebellar artery) or dissection is the most common cause of lateral medullary
syndrome, although tumour, demyelination, and trauma are also recognized
causes.
What is Lateral Rectus Palsy?
The lateral rectus muscle is one of the six eye muscles that control eye movement. The lateral rectus muscle mainly acts to pull the eye in the outward direction, keeping the eye in the center away from the nose or to pull the eye outward, toward the temple. With sixth nerve palsy, a person may see double.
What is environmental tilt?
A 14-year-old girl experienced two episodes of environmental tilt illusion. During both episodes, which lasted less than 1 minute, she perceived all objects within view as rotated 45 degrees clockwise. There were no auras, accompanying symptoms, or sequelae. Neuro-ophthalmic examination findings were normal except for a right relative afferent pupil defect (RAPD). Imaging disclosed a cystic mass in the left posterior thalamus with compression of the brachium of the left superior colliculus. Stereotactic biopsy revealed a pilocytic astrocytoma. This is the first case documenting environmental tilt illusion as an isolated symptom of a thalamic lesion. Disruption of vestibular connections between the posterior thalamus and the posterior parietal cortex may be the cause of this visual perceptive disorder.
What is Amblyopia?
It is also called lazy eye, is a disorder of sight in which the brain fails to process inputs from one eye and over time favours the other eye. It results in decreased vision in an eye that otherwise typically appears normal. The cause of amblyopia can be any condition that interferes with focusing during early childhood. This can occur from poor alignment of the eyes, an eye being irregularly shaped such that focusing is difficult, one eye being more near sighted or farsighted than the other, or clouding of the lens of an eye.
What is Medial medullary syndrome?
It is also known as inferior alternating syndrome, hypoglossal alternating hemiplegia, lower alternating hemiplegia, or Dejerine syndrome, is a type of alternating hemiplegia characterized by a set of clinical features resulting from occlusion of the anterior spinal artery. This results in the infarction of medial part of the medulla oblongata. The syndrome is said to be “alternating” because the lesion causes symptoms both contralaterally and ipsilaterally. Sensation of pain and temperature is preserved, because the spinothalamic tract is located more laterally in the brainstem and is also not supplied by the anterior spinal artery (instead supplied by the posterior inferior cerebellar arteries and the vertebral arteries).
What is the cause of Medial medullary syndrome?
It is a type of alternating hemiplegia characterized by a set of clinical features resulting from occlusion of the anterior spinal artery. This results in the infarction of medial part of the medulla oblongata.
What is a medial medullary infarct?
Medial medullary infarct is associated with clinical triad of ipsilateral hypoglossal palsy, contralateral hemiparesis, and contralateral lemniscal sensory loss. Variable manifestations may include isolated hemiparesis, tetraparesis, ipsilateral hemiparesis, I or C facial palsy, ataxia, vertigo, nystagmus, dysphagia.
What is lateral medullary syndrome?
Lateral medullary syndrome (also called Wallenberg syndrome and posterior inferior cerebellar artery syndrome) is a neurological disorder causing a range of symptoms due to ischemia in the lateral part of the medulla oblongata in the brainstem.
What is Skew deviation?
It is an unusual ocular deviation (strabismus), wherein the eyes move upward (hypertropia), but in opposite directions. Skew deviation is caused by abnormal prenuclear vestibular input to the ocular motor nuclei, most commonly due to brainstem or cerebellar stroke. Other causes include multiple sclerosis and head trauma
What is Laterocollis?
Laterocollis is a lateral head tilt; this may be seen in 10–15% of patients with torticollis.
What is Lateropulsion?
Lateropulsion or ipsipulsion is literally pulling to one side. The term may be used to describe ipsilateral axial lateropulsion after cerebellar infarcts preventing patients from standing upright causing them to lean towards the opposite side. Lateral medullary syndrome may be associated with lateropulsion of the eye towards the involved medulla, and there may also be lateropulsion of saccadic eye movements.
What medications stop hiccups?
Drugs that may be used to treat long-term hiccups include:
Baclofen.
Chlorpromazine.
Metoclopramide.
What is Lazarus Sign?
Various spontaneous and reflex movements are described in brain death, the
most dramatic of which has been labelled as the Lazarus sign, after Lazarus,
raised from the dead by Christ (John 11:1–44). This spinal reflex manifests as
flexion of the arms at the elbow, adduction of the shoulders, lifting of the arms,
dystonic posturing of the hands, and crossing of the hands.
What is Leucocoria?
Leucocoria is a white pupillary reflex, in contrast to the normal red reflex.
Causes include retinoblastoma, retinal detachment, toxocara infection, congenital cataract, and benign retinal hypopigmentation.
What is Levitation?
Spontaneous levitation may be displayed by an alien limb, more usually an arm
than a leg, indicative of parietal lobe pathology. It is most often seen in corticobasal (ganglionic) degeneration, but a few cases with pathologically confirmed
progressive supranuclear palsy have been reported.
What is Lhermitte’s Sign?
Lhermitte’s sign, or the ‘barber’s chair syndrome’, is a painless but unpleasant tingling or electric shock-like sensation in the back and spreading instantaneously down the arms and legs following neck flexion (active or passive). It is associated with pathology within the cervical spinal cord. Although most commonly encountered (and originally described) in multiple sclerosis, it is
not pathognomonic of demyelination and has been described with other local
pathologies such as:
• subacute combined degeneration of the cord (vitamin B12 deficiency);
nitrous oxide (N2O) exposure;
• traumatic or compressive cervical myelopathy (e.g. cervical spondylotic
myelopathy);
• epidural/subdural/intraparenchymal tumour;
• radiation myelitis;
• pyridoxine toxicity;
• inflammation, e.g. systemic lupus erythematosus, Behçet’s disease;
• cervical herpes zoster myelitis;
• cavernous angioma of the cervical cord.
Pathophysiologically, this movement-induced symptom may reflect the
exquisite mechanosensitivity of axons which are demyelinated or damaged in
some other way.
A ‘motor equivalent’ of Lhermitte’s sign, McArdle’s sign, has been described, as has ‘reverse Lhermitte’s sign’, a label applied either to the aforementioned symptoms occurring on neck extension, or in which neck flexion induces electrical shock-like sensation travelling from the feet upward.
What is McArdle’s sign?
It is a distinctive muscle weakness that affects patients with spinal cord disease, was first noted more than 30 years ago. The namesake of the “sign,” M.J. McArdle, was a professor of neurology in London, and one of his patients with advanced multiple sclerosis needed to extend his neck and tip his head back to maintain a steady gait.
What is Lid Lag?
Lid lag is present if a band of sclera is visible between the upper eyelid and the
corneal limbus on attempted downgaze (cf. lid retraction), seen for example in
thyroid eye disease (Von Graefe’s sign), progressive supranuclear palsy (Steele–
Richardson–Olszewski syndrome), and Guillain–Barré syndrome.
What is Lid Retraction?
Lid retraction is present if a band of sclera is visible between the upper eyelid and the corneal limbus in the primary position (cf. lid lag). This should be distinguished from contralateral ptosis. Recognized causes of lid retraction include
• Overactivity of levator palpebrae superioris:
Dorsal mesencephalic lesion (Collier’s sign)
Opposite to unilateral ptosis, e.g. in myasthenia gravis; retracted lid
may fall when ptotic lid raised; frontalis overactivity usually evident
Paradoxical lid retraction with jaw movement (jaw winking, Marcus
Gunn phenomenon)
• Overactivity of Müller’s muscle:
Irritative oculosympathetic lesions (Claude–Bernard syndrome)
• Contracture of the levator muscle:
Hyperthyroidism, Graves’ ophthalmopathy (Dalrymple’s sign): may be
associated lid lag
Myotonic syndromes
Aberrant oculomotor (III) nerve regeneration (pseudo-Von Graefe’s
sign)
• Cicatricial retraction of the lid, e.g. following trauma
• Hepatic disease (Summerskill’s sign)
• Guillain–Barré syndrome
Lower lid retraction may be congenital, or a sign of proptosis. Ectropion
may also be seen with lower lid tumour or chalazion, trauma with scarring, and
ageing.
What is Collier’s sign?
It is (also known as Collier’s tucked lid sign or posterior fossa stare) is bilateral or unilateral eyelid retraction. It is an accepted medical sign of a midbrain lesion, first described in 1927 by J Collier. With the eyes in the primary position, the sclera can be seen above the cornea, and further upgaze increases the distance between the eyelids and irises.
What is Dalrymple’s sign?
It is a widened palpebral (eyelid) opening, or eyelid spasm, seen in thyrotoxicosis (as seen in Graves’ disease, exophthalmic Goitre and other hyperthyroid conditions), causing abnormal wideness of the palpebral fissure. As a result of the retraction of the upper eyelid, the white of the sclera is visible at the upper margin of the cornea in direct outward stare.
What is pseudo Graefe’s sign (pseudo lid lag)?
Von Graefe’s sign (lid lag sign) is the immobility or lagging of the upper eyelid on downward rotation of the eye, indicating exophthalmic goitre (Graves’ Disease). A pseudo Graefe’s sign (pseudo lid lag) shows a similar lag, but is due to aberrant regeneration of fibres of the oculomotor nerve (III) into the elevator of the upper lid.
What is Stellwag’s sign?
It is a sign of infrequent or incomplete blinking associated with exophthalmos or Graves orbitopathy. It is accompanied by Dalrymple’s sign, which is a retraction of the upper eyelids resulting in an apparent widening of the palpebral opening. Stellwag’s sign is named after Austrian ophthalmologist.
What is sun set eyes?
The sunset eye sign (also known as the setting sun phenomenon) is a clinical phenomenon encountered in infants and young children with raised intracranial pressure (seen in up to 40% of children with obstructive hydrocephalus and 13% of children with shunt dysfunction 1). It consists of an up-gaze paresis with the eyes appearing driven downward.
What is Light-Near (Pupillary) Dissociation (LND)?
Light-near pupillary dissociation refers to the loss of pupillary light
reflexes, whilst the convergence–accommodation reaction is preserved (see
Pupillary Reflexes). This dissociation may be seen in a variety of clinical
circumstances:
• Argyll Robertson pupil: small irregular pupils with reduced reaction to light,
typically seen in neurosyphilis; the absence of miosis and/or pupillary irregularity has been referred to as pseudo-Argyll Robertson pupil, which may
occur with neurosarcoidosis, diabetes mellitus, and aberrant regeneration of
the oculomotor (III) nerve.
• Holmes–Adie pupil: dilated pupil showing strong but slow reaction to
accommodation but minimal reaction to light (tonic > phasic).
• Parinaud’s syndrome (dorsal rostral midbrain syndrome): due to a lesion
at the level of the posterior commissure and characterized by vertical
gaze palsy, lid retraction (Collier’s sign) or ptosis, and large regular pupils
responding to accommodation but not light.
What is Locked-In Syndrome?
The locked-in syndrome results from deefferentation, such that a patient is
awake, self-ventilating, and alert, but unable to speak or move; vertical eye movements and blinking are usually preserved, affording a channel for simple (yes/no) communication.
The most common cause of the locked-in syndrome is basilar artery thrombosis causing ventral pontine infarction (both pathological laughter and pathological crying have on occasion been reported to herald this event). Other
pathologies include pontine haemorrhage and central pontine myelinolysis.
Bilateral ventral midbrain and internal capsule infarcts can produce a similar
picture. Generally, this is irreversible, although recovery has on occasion been
recorded. The locked-in syndrome may be mistaken for abulia, akinetic mutism, coma,
and catatonia.
What is Trismus?
It is also sometimes called lockjaw, is a painful condition in which the chewing muscles of the jaw become contracted and sometimes inflamed, preventing the mouth from fully opening. For most people, fully opening the mouth means opening it beyond 35 millimetres (mm) wide a little greater than the width of two fingers.
What is pathological laughing?
pathological laughter. Uncontrolled laughter (occasionally accompanied by, or alternating with, uncontrolled crying), caused by pseudobulbar lesions of the brain. These lesions may result from lacunar strokes, multiple sclerosis, anoxic brain injury, and other forms of brain injury. See also: laughter.
What is Logoclonia?
Logoclonia is the tendency for a patient to repeat the final syllable of a word
when speaking; hence it is one of the reiterative speech disorders (cf. echolalia,
palilalia); Liepmann apparently coined this term in 1905 to indicate ‘continuous perseveration’. It may be described as the festinating repetition of individual
phonemes.
Logoclonia is an indicator of bilateral brain injury, usually involving subcortical structures, and may be seen in the late stages of dementia of Alzheimer type (but not in semantic dementia).
What is festinating gait?
festinating gait one in which the patient involuntarily moves with short, accelerating steps, often on tiptoe, with the trunk flexed forward and the legs flexed stiffly at the hips and knees. It is seen in Parkinson’s disease and other neurologic conditions that affect the basal ganglia.
What is Logopenia?
Logopenia is a reduced rate of language production, due especially to wordfinding pauses, but with relatively preserved phrase length and syntactically complete language, seen in aphasic syndromes, such as primary non-fluent aphasia.
What is Logorrhoea?
Logorrhoea is literally a flow of speech, or pressure of speech, denoting an
excessive verbal output, an abnormal number of words produced during each
utterance. Content is often irrelevant, disconnected, and difficult to interpret.
The term may be used for the output in the Wernicke/posterior/sensory type of
aphasia or for an output which superficially resembles Wernicke aphasia but in
which syntax and morphology are intact, rhythm and articulation are usually
normal, and paraphasias and neologisms are few. Moreover, comprehension is
better than anticipated in the Wernicke type of aphasia. Patients may be unaware
of their impaired output (anosognosia) due to a failure of self-monitoring.
Logorrhoea may be observed in subcortical (thalamic) aphasia, usually following recovery from lesions (usually haemorrhage) to the anterolateral nuclei.
Similar speech output may be observed in psychiatric disorders such as mania
and schizophrenia (schizophasia).
What is Long-tract signs?
It refers to symptoms that are attributable to the involvement of the long fiber tracts in the spinal cord, which connect the spinal cord to the brain and mediate spinal and motor functions. Functionally, a lesion anywhere along this tract can produce the same long tract signs. Signs of pyramidal tract dysfunction include spasticity, weakness, slowing of rapid alternating movements, hyperreflexia, and a Babinski sign
What is Schizophasia?
It, or word salad is language that is confused and often repetitious, symptomatic of various mental illnesses. It is usually associated with a manic presentation of bipolar affective disorder and other symptoms of serious mental illnesses, such as psychosis, including schizophrenia.
What does echolalia mean?
The person with echolalia may repeat noises, phrases, or words. Echolalia is a symptom of brain damage or psychiatric disorders, and the person with echolalia may or may not be able to communicate normally or understand others. Children with autism and developmental disorders, as well as very young children, may exhibit echolalia.
Is echolalia a symptom of autism?
Echolalia can be a symptom of various disorders including aphasia, dementia, traumatic brain injury, and schizophrenia, but it is most often associated with autism. Echolalia is a unique form of speech, and if your child is autistic it may be one of the first ways in which your child uses speech to communicate.
What is Mirror Agnosia?
It is a condition where even though the person knows that he is looking at mirror as evidenced by ability to identify the frame and the glass of the mirror, he fails to recognize the objects that are reflected in the mirror as reflections.
What is “Looking Glass Syndrome”?
It was discovered by UCSD Neuroscientists. When shown an object like a pen or candy on their left, the patients kept banging their hands against a mirror to their right, as if they believed the object in the mirror was not a reflection, but was real.
What is Lower Motor Neurone (LMN) Syndrome?
A lower motor neurone (LMN) syndrome constitutes a constellation of motor
signs resulting from damage to lower motor neurone pathways, i.e. from anterior horn cell distally, encompassing the motor roots, nerve plexuses, peripheral
nerves, and neuromuscular junction. Following the standard order of neurological examination of the motor system, the signs include
• Appearance:
muscle wasting; fasciculations (or ‘fibrillations’) may be observed or
induced, particularly if the pathology is at the level of the anterior horn
cell.
• Tone:
reduced tone (flaccidity, hypotonus), although this may simply reflect
weakness.
• Power:
weakness, often marked; depending on the precise pathological process, weakness often affects both flexor and extensor muscles equally
(although this is not always the case).
• Coordination:
depending on the degree of weakness, it may not be possible to comment on the integrity or otherwise of coordination in LMN syndromes;
in a pure LMN syndrome coordination will be normal.
• Reflexes:
depressed (hyporeflexia) or absent (areflexia); plantar responses are
flexor.
It is often possible to draw a clinical distinction between motor symptoms
resulting from lower or upper motor neurone pathology and hence to formulate
a differential diagnosis and direct investigations accordingly. Sensory features
may also be present in LMN syndromes if the pathology affects sensory as well
as motor roots, or both motor and sensory fibres in peripheral nerves.
What is Luria Test?
In clinical practice, we often use the Luria’s fist edge-palm test (FEP) to detect frontal lobe dysfunction. However, we have sometimes encountered patients with failure in this test following posterior lesions.
What is automatism?
These typically last for several seconds to minutes or sometimes longer, a time during which the subject is unaware of his/her actions. This type of automatic behaviour often occurs in certain types of epilepsy, such as complex partial seizures in those with temporal lobe epilepsy, or as a side effect of certain medications, such as zolpidem.
What is Akinetic mutism?
A state in which a person is unable to speak (mute) or move (akinetic). Akinetic mutism is often due to damage to the frontal lobes of the brain.
What does akinetic mutism mean?
Akinetic mutism is a medical term describing patients tending neither to move (akinesia) nor speak (mutism). Akinetic mutism was first described in 1941 as a mental state where patients lack the ability to move or speak. However, their eyes may follow their observer or be diverted by sound.
Can patients with akinetic mutism move?
Patients with akinetic mutism are not paralyzed, but lack the will to move. Many patients describe that as soon as they ‘will’ or attempt a movement, a ‘counter-will’ or ‘resistance’ rises up to meet them.
Can depression cause akinetic mutism?
Akinetic mutism can be misdiagnosed as depression, delirium, or locked-in syndrome, all of which are common following a stroke. Patients with depression can experience apathy, slurring of speech, and body movements similar to akinetic mutism.
What is a locked in syndrome?
Locked-in syndrome. Locked-in syndrome (LIS), also known as pseudo coma, is a condition in which a patient is aware but cannot move or communicate verbally due to complete paralysis of nearly all voluntary muscles in the body except for vertical eye movements and blinking.
How is locked-in syndrome diagnosed?
A diagnosis of locked-in syndrome is usually made clinically. A variety of tests may be performed to rule out other conditions. Such tests include magnetic resonance imaging (MRI), which shows the damage to the pons, and magnetic resonance angiography, which can show the blood clot in the arteries of the brainstem.
Is locked in syndrome difficult to diagnose?
Locked-in syndrome may be difficult to diagnose in some patients initially because some patients may be comatose for a while and then develop locked-in syndrome; some patients with a new onset stroke may resemble individuals with locked-in syndrome.
What is the definition for apathy?
Definition of apathy is lack of feeling or emotion ie impassiveness drug abuse leading to apathy and depression.
What does bradyphrenia mean?
Bradyphrenia is the slowness of thought common to many disorders of the brain.
What is bradyphrenia characterized by?
Bradyphrenia is characterized by: Slow thought process. This cognitive slowing causes disruptions of speech, mobility, sentence comprehension, executive function and working memory in Bradyphrenia patients. Increased latency of response Absence of voluntary motion Mental void or blank Reduce emotional concern.
Bradyphrenia is the slowness of thought common to many disorders of the brain. Disorders characterized by bradyphrenia include Parkinson’s disease and forms of schizophrenia consequently causing a delayed response and fatigue. Patients with bradyphrenia may describe or may manifest slowed thought processes, evidenced by increased latency of response and also involve severe memory impairment and poor motor control.
What is the aetiology of encephalitis?
Encephalitis is inflammation of the brain. The severity can be variable with symptoms including headache, fever, confusion, a stiff neck, and vomiting. Complications may include seizures, hallucinations, trouble speaking, memory problems, and problems with hearing.
Encephalitis can develop as a result of a direct infection to the brain by a virus, bacterium, or fungus, or when the immune system responds to a previous infection; the immune system mistakenly attacks brain tissue.
Causes of encephalitis include viruses such as herpes simplex virus and rabies as well as bacteria, fungi, or parasites. Other causes include autoimmune diseases and certain medications. In many cases the cause remains unknown. Risk factors include a weak immune system. Diagnosis is typically based on symptoms and supported by blood tests, medical imaging,
What is TBE?
Tick-borne encephalitis (TBE) is a viral infectious disease involving the central nervous system. The disease most often manifests as meningitis, encephalitis, or meningoencephalitis. Long-lasting or permanent neuropsychiatric consequences are observed in 10 to 20% of infected patients.
What is Rasmussen’s encephalitis?
Rasmussen’s encephalitis, is a rare inflammatory neurological disease, characterized by frequent and severe seizures, loss of motor skills and speech, hemiparesis, encephalitis, and dementia. The illness affects a single cerebral hemisphere and generally occurs in children under the age of 15.
What is Herpes viral encephalitis?
Herpes viral encephalitis, or herpes simplex encephalitis, is encephalitis due to herpes simplex virus. It is estimated to affect at least 1 in 500,000 individuals per year, and some studies suggest an incidence rate of 5.9 cases per 100,000 live births. About 90% of cases of herpes encephalitis are caused by herpes simplex virus-1, the same virus that causes cold sores. 57% of American adults are infected with HSV-1, which is spread through droplets, casual contact and sometimes sexual contact.
What is Japanese encephalitis?
Japanese encephalitis is an infection of the brain caused by the Japanese encephalitis virus. While most infections result in little or no symptoms, occasional inflammation of the brain occurs. In these cases, symptoms may include headache, vomiting, fever, confusion and seizures. This occurs about 5 to 15 days after infection. JEV is generally spread by mosquitoes, specifically those of the Culex type. Pigs and wild birds serve as a reservoir for the virus.
What is Anti-NMDA receptor encephalitis?
Anti-NMDA receptor encephalitis is a type of brain inflammation due to antibodies. Early symptoms may include fever, headache, and feeling tired. This is then typically followed by psychosis which presents with false beliefs and seeing or hearing things that others do not see or hear. People are also often agitated or confused. Over time seizures, decreased breathing, and blood pressure and heart rate variability typically occur. About half of cases are associated with tumors.
What is Acute encephalitis syndrome (AES)?
Acute encephalitis syndrome (AES) is characterized by an acute onset of fever and clinical neurological manifestation that includes mental confusion, disorientation, delirium, or coma. Apart from viral encephalitis, severe form of leptospirosis and toxoplasmosis can cause AES.
What are the causes of catatonia?
Catatonia can occur in association with a psychiatric disorder, like schizophrenia, or in association with a medical condition such as encephalitis. In some patients, catatonia may be present without a known cause. Catatonia is usually episodic, meaning that episodes of catatonia come and go.
Is Catatonia a positive or negative symptom?
Catatonic motor behaviours are a type of disturbed behaviour (and a negative as opposed to a positive symptom) that sometimes occurs when schizophrenia goes untreated. In catatonia, peoples’ reaction to their surroundings becomes remarkably decreased.
What causes catatonic Behavior?
Catatonia is believed to be caused by irregularities in the dopamine, gamma-aminobutyric acid (GABA), and glutamate neurotransmitter systems. It’s often accompanied by an underlying neurological, psychiatric, or physical illness.
What is catatonic stupor?
catatonic stupor. a form of catatonia characterized by a marked decrease in response to the environment with a reduction in spontaneous movement. Patients with this disorder sometimes appear unaware of their environment.
What is lorazepam challenge test?
Lorazepam challenge test (administration of lorazepam 1-2 mg by mouth, intravenous or intramuscular) is done in catatonia, and there is a rapid resolution of all symptoms temporarily. In our patient, the test was positive.
What is the treatment for catatonic schizophrenia?
As with schizophrenia, the most effective treatment for catatonic schizophrenia is medication. Unlike schizophrenia, though, people with catatonic schizophrenia should not take antipsychotic medications. Fast-acting, injectable benzodiazepines may offer relief for some catatonic symptoms, including anxiety.
What is Frontal lobe syndrome (FLS)?
Frontal lobe syndrome (FLS) reflects damage to the prefrontal regions of the frontal lobe. It is characterised by deterioration in behaviour and personality in a previously normal individual.
What diseases are due to disorders in the frontal lobe?
Psychiatric diseases such as schizophrenia and major depression. In addition, any neurologic or psychiatric disease that can affect the frontal lobe (eg, multiple sclerosis, CNS lupus) may be associated with frontal lobe dysfunction.
What are the early signs of frontotemporal dementia?
Early signs of frontotemporal dementia may involve the following symptoms:
Apathy or an unwillingness to talk.
Change in personality and mood, such as depression.
Lack of inhibition or lack of social tact.
Obsessive or repetitive behaviour, such as compulsively shaving or collecting items.
Unusual verbal, physical or sexual behaviour.
What are symptoms of autism disorder?
Children with Autism Spectrum Disorder are often restricted, rigid, and even obsessive in their behaviours, activities, and interests. Symptoms may include: Repetitive body movements (hand flapping, rocking, spinning); moving constantly. Obsessive attachment to unusual objects (rubber bands, keys, light switches)
What is psychomotor disorder?
The term “psychomotor” refers to physical activity and how your mental processes either affect or govern it. It is used in the diagnosis of bipolar disorder to describe any changes indicative of a manic or depressive episode.
What are psychomotor disturbances-?
A psychomotor disturbance that may involve muscle rigidity, stupor or mutism, purposeless movements, negativism, echolalia, and inappropriate or unusual posturing and is associated with various medical conditions (such as schizophrenia and mood disorders)
What is psychomotor activity?
The term “psychomotor” refers to physical activity and how your mental processes either affect or govern it. It is used in the diagnosis of bipolar disorder to describe any changes indicative of a manic or depressive episode. … In bipolar disorder, as with other mood disorders, psychomotor activity can be affected in one of two ways: it can be either increased, which is known as psychomotor agitation, or it can be decreased, which we call psychomotor retardation.
What is psychomotor function?
Psychomotor function: processes affecting the coordination of sensory or cognitive processes and motor activity.
How does depression affect psychomotor skills?
Psychomotor skills are skills where movement and thinking are combined. This includes things like balance and coordination. Psychomotor skills are known to be negatively affected by depression. Greater psychomotor skill impairment is seen in older individuals and in people with longer and more severe depressions.
What is psychomotor retardation mean?
Psychomotor retardation (also known as “psychomotor impairment” or “motor mental retardation” or “psychomotor slowing”) involves a slowing-down of thought and a reduction of physical movements in an individual. Psychomotor retardation can cause a visible slowing of physical and emotional reactions, including speech and affect.
What is abulia?
Abulia (aboulia) is a ‘syndrome of hypofunction’, characterized by a lack of initiative, spontaneity and drive (aspontaneity), apathy, slowness of thought(bradyphrenia), and blunting of emotional responses and response to external stimuli. It may be confused with the psychomotor retardation of depression and is sometimes labelled as ‘pseudo depression’. More plausibly, abulia has been thought of as a minor or partial form of akinetic mutism. A distinction maybe drawn between abulia major (akinetic mutism) and abulia minor, a lesser degree of abulia associated particularly with bilateral caudate stroke and thalamic infarcts in the territory of the polar artery and infratentorial stroke. There may also be some clinical overlap with catatonia. Abulia may result from frontal lobe damage, most particularly that involving the frontal convexity.
What are the causes of abulia?
Pathologically, abulia may be observed in:
Infarcts in anterior cerebral artery territory and ruptured anterior communicating artery aneurysms, causing basal forebrain damage; Closed head injury;
Parkinson’s disease; sometimes as a forerunner of a frontal lobe dementia;
Other causes of frontal lobe disease: tumour, abscess;
Metabolic, electrolyte disorders: hypoxia, hypoglycaemia, hepatic encephalopathy. Treatment is of the underlying cause where possible.
What is Acalculia?
Acalculia, or dyscalculia, is difficulty or inability in performing simple mentalarithmetic. This depends on two processes, number processing and calculation; a deficit confined to the latter process is termed anarithmetia. Acalculia may be classified as:
Primary
A specific deficit in arithmetical tasks, more severe than any other coexisting cognitive dysfunction.
Secondary
In the context of other cognitive impairments, for example of language (aphasia, alexia, or agraphia for numbers), attention, memory, or space perception (e.g. neglect). Acalculia may occur in association with alexia, agraphia, finger agnosia, right–left disorientation, and difficulty spelling words as part of the Gerstmann syndrome with lesions of the dominant parietal lobe. Secondary acalculia is the more common variety. Isolated acalculia may be seen with lesions of:
dominant (left) parietal/temporal/occipital cortex, especially involving the angular gyrus (Brodmann areas 39 and 40) medial frontal lobe (impaired problem-solving ability?); subcortical structures (caudate nucleus, putamen, internal capsule). Impairments may be remarkably focal, for example one operation (e.g. subtraction) may be preserved whilst all others are impaired. In patients with mild-to-moderate Alzheimer’s disease with dyscalculia but no attentional or language impairments, cerebral glucose metabolism was found to be impaired in the left inferior parietal lobule and inferior temporal gyrus. Preservation of calculation skills in the face of total language dissolution (pro-duction and comprehension) has been reported with focal left temporal lobe atrophy probably due to Pick’s disease.
What are Abdominal Reflexes?
Both superficial and deep abdominal reflexes are described, of which the superficial (cutaneous) reflexes are the more commonly tested in clinical practice.
A wooden stick or pin is used to scratch the abdominal wall, from the flank to the midline, parallel to the line of the dermatomal strips, in upper (supraumbilical), middle (umbilical), and lower (infraumbilical) areas. The manoeuvre is best performed at the end of expiration when the abdominal muscles are relaxed, since the reflexes may be lost with muscle tensing; to avoid this, patients should lie supine with their arms by their sides.
Superficial abdominal reflexes are lost in a number of circumstances:
• Normal ageing;
• Obesity;
• Following abdominal surgery;
• Following multiple pregnancies;
• In acute abdominal disorders (Rosenbach’s sign).
However, absence of all superficial abdominal reflexes may be of localizing
value for corticospinal pathway damage (upper motor neurone lesions) above T6.
Lesions at or below T10 lead to selective loss of the lower reflexes with the upper
and middle reflexes intact, in which case Beevor’s sign may also be present. All
abdominal reflexes are preserved with lesions below T12.
Abdominal reflexes are said to be lost early in multiple sclerosis, but late in
motor neurone disease, an observation of possible clinical use, particularly when
differentiating the progressive lateral sclerosis variant of motor neurone disease
from multiple sclerosis. However, no prospective study of abdominal reflexes in
multiple sclerosis has been reported.
What is Rosenbach’s Sign?
Rosnebach’s sign indicates unusual tremor of the eyelids which is often associated with various diseases involving high levels of thyroxine. What are the diseases associated with Rosenbach’s sign? 1. Grave’s disease 2. Hyperthyroidism 3. Thyroid storm
What is Beevor’s sign?
Beevor’s sign is medical sign seen in the selective weakness of the lower abdominal muscles, involving the movement of the navel towards the head on flexing the neck.
What is Achilles Reflex?
Plantar flexion at the ankle following phasic stretch of the Achilles tendon constitutes the Achilles reflex or ankle jerk, mediated through sacral segments S1
and S2 and the sciatic and posterior tibial nerves. This reflex may be elicited in
several ways: by a blow with a tendon hammer directly upon the Achilles tendon (patient supine, prone with knee flexed, or kneeling) or with a plantar strike.
The latter, though convenient and quick, is probably the least sensitive method,
since absence of an observed muscle contraction does not mean that the reflex is
absent; the latter methods are more sensitive.
The Achilles reflex is typically lost in polyneuropathies and S1 radiculopathy.
What is Akinesia?
Akinesia is a lack of, or an inability to initiate, voluntary movements. More
usually in clinical practice there is a difficulty (reduction, delay), rather than complete inability, in the initiation of voluntary movement, perhaps better termed
bradykinesia, or reduced amplitude of movement or hypokinesia. These difficulties cannot be attributed to motor unit or pyramidal system dysfunction.
Reflexive motor activity may be preserved (kinesis paradoxica). There may be
concurrent slowness of movement, also termed bradykinesia.
Akinesia may coexist with any of the other clinical features of extrapyramidal
system disease, particularly rigidity, but the presence of akinesia is regarded as an
absolute requirement for the diagnosis of parkinsonism. Hemiakinesia may be a
feature of motor neglect of one side of the body (possibly a motor equivalent of
sensory extinction). Bilateral akinesia with mutism (akinetic mutism) may occur
if pathology is bilateral. Pure akinesia, without rigidity or tremor, may occur:
if levodopa-responsive, this is usually due to Parkinson’s disease; if levodopa unresponsive, it may be the harbinger of progressive supranuclear palsy. A few
patients with PSP have ‘pure akinesia’ without other features until late in the
disease course.
Neuroanatomically, akinesia is a feature of disorders affecting
• frontal–subcortical structures, e.g. the medial convexity subtype of frontal
lobe syndrome;
• basal ganglia;
• ventral thalamus;
• limbic system (anterior cingulate gyrus).
Neurophysiologically, akinesia is associated with loss of dopamine projections from the substantia nigra to the putamen.
What are the causes of akinesia?
Pathological processes underpinning akinesia include
• Neurodegeneration, e.g. Parkinson’s disease, progressive supranuclear palsy
(Steele–Richardson–Olszewski syndrome), and multiple system atrophy
(striatonigral degeneration); akinesia may occur in frontotemporal lobar
degeneration syndromes, Alzheimer’s disease, and some prion diseases;
• Hydrocephalus;
• Neoplasia, e.g. butterfly glioma of the frontal lobes;
• Cerebrovascular disease.
Akinesia resulting from nigrostriatal dopamine depletion (i.e. idiopathic
What is Akinetic Mutism?
Akinetic mutism is a ‘syndrome of negatives’, characterized by a lack of voluntary movement (akinesia), absence of speech (mutism), and lack of response
to question and command, but with normal alertness and sleep–wake cycles
(cf. coma). Blinking (spontaneous and to threat) is preserved. Frontal release
signs, such as grasping and sucking, may be present, as may double incontinence, but there is a relative paucity of upper motor neurone signs affecting either
side of the body, suggesting relatively preserved descending pathways. Akinetic
mutism represents an extreme form of abulia, hence sometimes referred to as
abulia major.
Occasionally, treatment of the cause may improve akinetic mutism (e.g.
relieving hydrocephalus). Agents such as dopamine agonists (e.g. bromocriptine),
ephedrine and methylphenidate have also been tried.
What is Alien Grasp Reflex?
The term alien grasp reflex has been used to describe a grasp reflex occurring
in full consciousness, which the patient could anticipate but perceived as alien
(i.e. not modified by will), occurring in the absence of other abnormal movements. These phenomena were associated with an intrinsic tumour of the right
(non-dominant) frontal lobe. It was suggested that the grasp reflex and alien
hand syndromes are not separate entities but part of the spectrum of frontal lobe
dysfunction, the term ‘alien grasp reflex’ attempting to emphasize the overlap.
What are the causes of Alien Hand, Alien Limb?
An alien limb, most usually the arm but occasionally the leg, is one which manifests slow, involuntary, wandering (levitating), quasi-purposive movements.
Recognized pathological associations of alien limb include
• Corticobasal (ganglionic) degeneration;
• Corpus callosum tumours, haemorrhage;
• Medial frontal cortex infarction (territory of the anterior cerebral artery);
• Trauma and haemorrhage affecting both corpus callosum and medial
frontal area;
• Alzheimer’s disease, familial Creutzfeldt–Jakob disease (very rare);
• Posterior cerebral artery occlusion (sensory variant);
• Following commissurotomy (corpus callosotomy alone insufficient).
Functional imaging studies in corticobasal degeneration, along with the evidence from focal vascular lesions, suggest that damage to and/or hypometabolism
of the medial frontal cortex (Brodmann area 32) and the supplementary motor
area (Brodmann area 6) is associated with alien limb phenomena. More generally, it seems that these areas are involved in the execution of learned motor
programs, and damage there
What is Amaurosis?
Amaurosis is visual loss, with the implication that this is not due to refractive
error or intrinsic ocular disease. The term is most often used in the context
of amaurosis fugax, a transient monocular blindness, which is most often due
to embolism from a stenotic ipsilateral internal carotid artery (ocular transient
ischaemic attack). Giant cell arteritis, systemic lupus erythematosus, and the
antiphospholipid antibody syndrome are also recognized causes. Gaze-evoked
amaurosis has been associated with a variety of mass lesions and is thought to
result from decreased blood flow to the retina from compression of the central
retinal artery with eye movement.
What is Amblyopia?
Amblyopia refers to poor visual acuity, most usually in the context of a ‘lazy
eye’, in which the poor acuity results from the failure of the eye to establish normal cortical representation of visual input during the critical period of visual
maturation (between the ages of 6 months and 3 years). This may result from:
• strabismus;
• uncorrected refractive error;
• stimulus deprivation.
Amblyopic eyes may demonstrate a relative afferent pupillary defect and
sometimes latent nystagmus.
Amblyopia may not become apparent until adulthood, when the patient suddenly becomes aware of unilateral poor vision. The finding of a latent strabismus
(heterophoria) may be a clue to the fact that such visual loss is long-standing.
The word amblyopia has also been used in other contexts: bilateral simultaneous development of central or centrocaecal scotomas in chronic alcoholics has
often been referred to as tobacco–alcohol amblyopia, although nutritional optic
neuropathy is perhaps a better term.
What is Abadie’s Sign?
Abadie’s sign is the absence or diminution of pain sensation when exerting deep
pressure on the Achilles tendon by squeezing. This is a frequent finding in the
tabes dorsalis variant of neurosyphilis, i.e. with dorsal column disease.
What are Abdominal Reflexes?
Both superficial and deep abdominal reflexes are described, of which the superficial (cutaneous) reflexes are the more commonly tested in clinical practice.
A wooden stick or pin is used to scratch the abdominal wall, from the flank
to the midline, parallel to the line of the dermatomal strips, in upper (supraumbilical), middle (umbilical), and lower (infraumbilical) areas. The manoeuvre is
best performed at the end of expiration when the abdominal muscles are relaxed,
since the reflexes may be lost with muscle tensing; to avoid this, patients should
lie supine with their arms by their sides.
Superficial abdominal reflexes are lost in a number of circumstances:
• Normal ageing;
• Obesity;
• Following abdominal surgery;
• Following multiple pregnancies;
• In acute abdominal
What is Amnesia?
Amnesia is an impairment of episodic memory or memory for personally experienced events (autobiographical memory).
Classification of amnesic syndromes into subtypes has been proposed, since
lesions in different areas produce different deficits reflecting functional subdivision within the system; thus, left temporal lesions produce problems in the
verbal domain, right-sided lesions affect non-verbal/visual memory. A distinction between medial temporal pathology (e.g. hippocampus), leading to difficulty
encoding new memories (anterograde amnesia and temporally limited retrograde amnesia), and diencephalic pathology (e.g. Korsakoff ’s syndrome), which
causes difficulty retrieving previously acquired memories (extensive retrograde
amnesia) with diminished insight and a tendency to confabulation, has been
suggested, but overlap may occur. A frontal amnesia has also been suggested,
although impaired attentional mechanisms may contribute. Functional imaging
studies suggest that medial temporal lobe activation is required for encoding
with additional prefrontal activation with ‘deep’ processing; medial temporal and
prefrontal activations are also seen with retrieval.
What are the causes of amnesia?
Many causes of amnesia are recognized, including
• Acute/transient:
Closed head injury;
Drugs;
Transient global amnesia;
Transient epileptic amnesia;
Transient semantic amnesia (very rare).
• Chronic/persistent:
Alzheimer’s disease (may show isolated amnesia in early disease);
Sequela of herpes simplex encephalitis;
Limbic encephalitis (paraneoplastic or non-paraneoplastic);
Hypoxic brain injury;
Temporal lobectomy (bilateral; or unilateral with previous contralateral injury, usually birth asphyxia);
Bilateral posterior cerebral artery occlusion;
Korsakoff’s syndrome;
Bilateral thalamic infarction;
Third ventricle tumour, cyst;
Focal retrograde amnesia (rare).
Few of the chronic persistent causes of amnesia are amenable to specific
treatment. Plasma exchange or intravenous immunoglobulin therapy may be
helpful in non-paraneoplastic limbic encephalitis associated with autoantibodies
directed against voltage-gated potassium channels.
Functional or psychogenic amnesia may involve failure to recall basic autobiographical details such as name and address. Reversal of the usual temporal gradient of memory loss may be observed
What is Anaesthesia?
Anaesthesia (anesthesia) is a complete loss of sensation; hypoaesthesia (hypaesthesia, hypesthesia) is a diminution of sensation. Hence in Jacksonian terms,
these are negative sensory phenomena. Anaesthesia may involve all sensory
modalities (global anaesthesia, as in general surgical anaesthesia) or be selective (e.g. thermoanaesthesia, analgesia). Regional patterns of anaesthesia are
described, e.g. ‘glove-and-stocking anaesthesia’ in peripheral neuropathies and
‘saddle anaesthesia’ involving S3-5 dermatomes resulting from a cauda equina
syndrome.
Anaesthesia is most often encountered after resection or lysis of a peripheral
nerve segment, whereas paraesthesia or dysaesthesia (positive sensory phenomena) reflects damage to a nerve which is still in contact with the cell body.
Anaesthesia dolorosa, or painful anaesthesia, is a persistent unpleasant pain (i.e. a positive sensory phenomenon) which may be experienced
in the distribution of a resected nerve, e.g. following neurolytic treatment
for trigeminal neuralgia, usually with delayed onset. This deafferentation
pain may respond to various medications, including tricyclic antidepressants, carbamazepine.
What is Analgesia?
Analgesia or hypoalgesia refers to a complete loss or diminution, respectively, of
pain sensation, or the absence of a pain response to a normally painful stimulus. These negative sensory phenomena may occur as one component of total
sensory loss (anaesthesia) or in isolation. Consequences of analgesia include
the development of neuropathic ulcers, burns, Charcot joints, even painless
mutilation, or amputation. Analgesia may occur in:
• peripheral nerve lesions, e.g. hereditary sensory and autonomic neuropathies
(HSAN), leprosy;
• central spinal cord lesions which pick off the decussating fibres of the
spinothalamic pathway in the ventral funiculus (with corresponding thermoanaesthesia), e.g. syringomyelia;
• cortical lesions, e.g. medial frontal lobe syndrome (akinetic type).
Congenital syndromes of insensitivity to pain were once regarded as a central
pain asymbolia (e.g. Osuntokun’s syndrome)
What is Anal Reflex?
Contraction of the external sphincter ani muscle in response to a scratch stimulus in the perianal region, testing the integrity of the S4/S5 roots, forms the
anal or wink reflex. This reflex may be absent in some normal elderly individuals, and absence does not necessarily correlate with urinary incontinence.
External anal responses to coughing and sniffing are part of a highly consistent
and easily elicited polysynaptic reflex, whose characteristics resemble those of the
conventional scratch-induced anal reflex.
What is Anarthria?
Anarthria is the complete inability to articulate words (cf. dysarthria). This is
most commonly seen as a feature of the bulbar palsy of motor neurone disease
What is Anhidrosis?
Anhidrosis, or hypohidrosis, is a loss or lack of sweating. This may be due to primary autonomic failure or due to pathology within the posterior hypothalamus
(‘sympathetic area’).
Anhidrosis may occur in various neurological disorders, including multiple
system atrophy, Parkinson’s disease, multiple sclerosis, caudal to a spinal cord
lesion, and in some hereditary sensory and autonomic neuropathies. Localized
or generalized anhidrosis may be seen in Holmes–Adie syndrome, and unilateral
anhidrosis may be seen in Horner’s syndrome if the symptomatic lesion is distal
to the superior cervical ganglion.
What is Anismus?
Anismus, also known as puborectalis syndrome, is paradoxical contraction of the
external anal sphincter during attempted defaecation, leading to faecal retention
and a complaint of constipation. This may occur as an idiopathic condition in
isolation or as a feature of the off periods of idiopathic Parkinson’s disease. It
is thought to represent a focal dystonia and may be helped temporarily by local
injections of botulinum toxin.
What is Anisocoria?
Anisocoria is an inequality of pupil size.
Affected pupil is constricted (miosis; oculosympathetic paresis),
as in:
Horner’s syndrome;
Argyll Robertson pupil;
Cluster headache.
Anisocoria greater in bright light/less in dim light suggests a defect
in parasympathetic innervation to the pupil. Affected pupil is dilated
(mydriasis; oculoparasympathetic paresis), as in:
Holmes–Adie pupil (vermiform movements of the pupil margin may
be visible with a slit lamp);
Oculomotor (III) nerve palsy (efferent path from Edinger–Westphal
nucleus);
Mydriatic agents (phenylephrine, tropicamide);
Anticholinergic agents (e.g. asthma inhaler accidentally puffed into
one eye).
What is Anomia?
Anomia or dysnomia is a deficit in naming or word-finding. Anomia may often be seen as
a residual deficit following recovery from other types of aphasia. Anomia may
occur with any dominant hemisphere space-occupying lesion, and as a feature of
semantic dementia, being more prominent in this condition than in Alzheimer’s
disease.
What is Anosmia?
Anosmia is the inability to perceive smells due to damage to the olfactory pathways (olfactory neuroepithelium, olfactory nerves, rhinencephalon). Olfaction
may be tested with kits containing specific odours (e.g. clove, turpentine); each
nostril should be separately tested. Unilateral anosmia may be due to pressure
on the olfactory bulb or tract, e.g. due to a subfrontal meningioma.
Anosmia may be congenital (e.g. Kallman’s syndrome, hypogonadotrophic
hypogonadism, a disorder of neuronal migration) or, much more commonly,
acquired. Rhinological disease (allergic rhinitis, coryza) is by far the most common cause; this may also account for the impaired sense of smell in smokers.
Head trauma is the most common neurological cause, due to shearing off of the
olfactory fibres as they pass through the cribriform plate. Recovery is possible
in this situation due to the capacity for neuronal and axonal regeneration within
the olfactory pathways. Olfactory dysfunction is also described in Alzheimer’s
disease and Parkinson’s disease, possibly as an early phenomenon, due to pathological involvement of olfactory pathways. Patients with depression may also
complain of impaired sense of smell. Loss of olfactory acuity may be a feature of normal ageing
What is Anosognosia?
Anosognosia refers to a patient’s unawareness or denial of their illness. The term
was first used by von Monakow (1885) and has been used to describe denial
of blindness (Anton’s syndrome), deafness, hemiplegia (Babinski), hemianopia,
aphasia, and amnesia. Some authorities would question whether this unawareness is a true agnosia or rather a defect of higher-level cognitive integration (i.e.
perception).
Anosognosia with hemiplegia most commonly follows right hemisphere
injury (parietal and temporal lobes) and may be associated with left hemineglect and left-sided hemianopia; it is also described with right thalamic and
basal ganglia lesions. Many patients with posterior aphasia (Wernicke type) are
unaware that their output is incomprehensible or jargon, possibly through a failure to monitor their own output. Cerebrovascular disease is the most common
pathology associated with anosognosia, although it may also occur with neurodegenerative disease, for example, the cognitive anosognosia in some patients with Alzheimer’s disease.
The neuropsychological mechanisms of anosognosia are unclear: the
hypothesis that it might be accounted for by personal neglect (asomatognosia),
which is also more frequently observed after right hemisphere lesions, would
seem to have been disproved experimentally by studies using selective hemisphere
anaesthesia in which the two may be dissociated, a dissociation which may also
be observed clinically. In Alzheimer’s disease, anosognosia may be related to
memory dysfunction and executive dysfunction
At a practical level, anosognosia may lead to profound difficulties with
neurorehabilitation. Temporary resolution of anosognosia has been reported
following vestibular stimulation (e.g. with caloric testing).
What is Antecollis?
Antecollis (anterocollis) is forward flexion of the neck. It may be a feature of multiple system atrophy ( retrocollis in progressive supranuclear palsy), a sustained
dystonic posture in advanced Parkinson’s disease, and, unusually, in spasmodic
torticollis.
Forward flexion of the head onto the chest is a feature in the ‘dropped head
syndrome’.
What is Anserina?
Autonomically mediated piloerection and thermoconstriction may produce
‘goosebumps’, cold and bumpy skin which may be likened to that of a plucked
goose. Loss of anserina may be a feature of some autonomic disorders.
What is Antecollis?
Antecollis (anterocollis) is forward flexion of the neck. It may be a feature of multiple system atrophy (cf. retrocollis in progressive supranuclear palsy), a sustained
dystonic posture in advanced Parkinson’s disease, and, unusually, in spasmodic
torticollis.
Forward flexion of the head onto the chest is a feature in the ‘dropped head
syndrome’.
What is Anteflexion?
Anteflexion is forward flexion of the trunk, as typical of the stooped posture seen
in Parkinson’s disease.
What is Anton’s Syndrome?
Anton’s syndrome is cortical blindness accompanied by denial of the visual
defect (visual anosognosia), with or without confabulation. The syndrome most
usually results from bilateral posterior cerebral artery territory lesions causing
occipital or occipitoparietal infarctions but has occasionally been described with
anterior visual pathway lesions associated with frontal lobe lesions. It may also
occur in the context of dementing disorders or delirium.
What is Anwesenheit?
A vivid sensation of the presence of somebody either somewhere in the room or
behind the patient has been labelled as anwesenheit (German: presence), presence hallucination, minor hallucination, or extracampine hallucination. This
phenomenon is relatively common in Parkinson’s disease, occurring in isolation
or associated with formed visual hallucinations.
What is Apathy?
Apathy is a neurobehavioral disorder which may be characterized by:
(1) A lack of motivation relative to the patient’s previous level of functioning or
the standards of age and culture.
(2) Presence of at least one of the following:
(a) Diminished goal-directed behaviour: lack of effort, dependency on others to
structure activity;
(b) Diminished goal-directed cognition: lack of interest, concern about personal
problems;
(c) Diminished concomitants of goal-directed behaviour: unchanging affect,
lack of emotional responsiveness.
An Apathy Inventory has been developed based on these criteria.
Hence, listlessness, paucity of spontaneous movement (akinesia) or speech
(mutism), and lack of initiative, spontaneity, and drive may be features of apathy These are also all features of the abulic state, and it has been suggested that
apathy and abulia represent different points on a continuum of motivational and
emotional deficit, abulia being at the more severe end. The diminished motivation
of apathy should not be attributable to impaired level of consciousness, emotional distress, or cognitive impairment although it may coexist with the latter, as
in Alzheimer’s disease. Apathy is a specific neuropsychiatric syndrome, distinct
from depression.
Apathy may be observed in diseases affecting frontal–subcortical structures, for example, in the frontal lobe syndrome affecting the frontal convexity,
or following multiple vascular insults to paramedian diencephalic structures
(thalamus, subthalamus, posterior lateral hypothalamus, mesencephalon) or the
posterior limb of the internal capsule; there may be associated cognitive impairment of the so-called subcortical type in these situations (e.g. in Huntington’s
disease). Apathy is also described following amphetamine or cocaine withdrawal, in neuroleptic-induced akinesia and in psychotic depression. Selective
serotonin-reuptake inhibitors may sometimes be helpful in the treatment of
apathy.
What is Aphasia?
Aphasia, or dysphasia, is an acquired loss or impairment of language function. Language may be defined as the complex system of symbols used for
communication (including reading and writing), encompassing various linguistic components (phonetic, phonemic, semantic/lexical, syntactic, pragmatic),
all of which are dependent on dominant hemisphere integrity. Non-linguistic
components of language (emotion, inflection, cadence), collectively known as
prosody, may require contributions from both hemispheres. Language is distinguished from speech (oral communication), disorders of which are termed
dysarthria or anarthria. Dysarthria and aphasia may coexist but are usually
separable.
Clinical assessment of aphasia requires analysis of the following features,
through listening to the patient’s spontaneous speech, asking questions or giving
commands, and asking the patient to repeat, name, read and write:
• Fluency: is output effortful, laboured, with agrammatism and dysprosody
(non-fluent); or flowing, with paraphasias and neologisms (fluent)?
• Comprehension: spared or impaired?
• Repetition: preserved or impaired?
• Naming: preserved or impaired?
• Reading: evidence of alexia?
• Writing: evidence of agraphia?
Aphasias most commonly follow a cerebrovascular event: the specific type
of aphasia may change with time following the event, and discrepancies may be
observed between classically defined clinicoanatomical syndromes and the findings of everyday practice. Aphasia may also occur with space-occupying lesions
and in neurodegenerative disorders, often with other cognitive impairments (e.g.
Alzheimer’s disease) but sometimes in isolation (primary non-fluent aphasia,
semantic dementia).
What is Aphemia?
Aphemia was the name originally given by Broca to the language disorder subsequently named ‘Broca’s aphasia’. The term is now used to describe a motor
disorder of speech production with preserved comprehension of spoken and written language. This syndrome has also been called phonetic disintegration (cf.
phonemic disintegration), pure anarthria, apraxic dysarthria, cortical dysarthria,
verbal apraxia, subcortical motor aphasia, alalia, pure motor aphasia, small or
mini-Broca’s aphasia, and kinetic speech production disorder, reflecting the differing views as to the nature of the underlying disorder (aphasia, dysarthria,
apraxia). Aphemia probably encompasses at least some cases of the ‘foreign
accent syndrome’, in which altered speech production and/or prosody makes
speech output sound foreign. Such conditions may stand between pure disorders
of speech (i.e. dysarthrias) and of language (i.e. aphasias).
What is Applause Sign?
To elicit the applause sign, also known as the clapping test or three clap test,
the patient is asked to clap the hands three times. The tendency to clap more
than three times, even when demonstrated by the examiner, is said to be specific
to striatal dysfunction and is seen in progressive supranuclear palsy to a greater
extent than in Parkinson’s disease, but not in frontotemporal dementia.
What is Aposiopesis?
Critchely used this term to denote a sentence which is started but not finished, as
in the aphasia associated with dementia.
What is Apraxia?
Apraxia or dyspraxia is a disorder of movement characterized by the inability
to perform a voluntary motor act despite an intact motor system (i.e. no ataxia,
weakness) and without impairment in level of consciousness. Automatic/reflex
actions are preserved, hence there is a voluntary–automatic dissociation; some
authors see this as critical to the definition of apraxia. Different types of
apraxia has been delineated, the standard classification being that of Liepmann
(1900):
• Ideational apraxia, conceptual apraxia:
A deficit in the conception of a movement; this frequently interferes
with daily motor activities and is not facilitated by the use of objects;
there is often an associated aphasia.
• Ideomotor apraxia (IMA):
A disturbance in the selection of elements that constitute a movement
(e.g. pantomiming the use of tools); in contrast to ideational apraxia,
this is a ‘clinical’ disorder inasmuch as it does not greatly interfere with
everyday activities; moreover, use of objects may facilitate movement;
it may often be manifest as the phenomenon of using body part as
object, e.g. in demonstrating how to use a toothbrush or how to hammer a nail, a body part is used to represent the object (finger used as
toothbrush, fist as hammer).
• Limb-kinetic, or melokinetic, apraxia:
Slowness, clumsiness, awkwardness in using a limb, with a temporal
decomposition of movement; difficult to disentangle from pure motor
deficits associated with corticospinal tract lesions.
Apraxia may also be defined anatomically:
• Parietal (posterior):
Ideational and ideomotor apraxia are seen with unilateral lesions of
the inferior parietal lobule (most usually of the left hemisphere) or
premotor area of the frontal lobe (Brodmann areas 6 and 8).
• Frontal (anterior):
Unilateral lesions of the supplementary motor area are associated with
impairment in tasks requiring bimanual coordination, leading to difficulties with alternating hand movements, drawing alternating patterns
(e.g. m n m n in joined up writing: alternating sequences test, Luria
figures). This may be associated with the presence of a grasp reflex and
alien limb phenomena (limb-kinetic type of apraxia).
Apraxia is more common and severe with left hemisphere lesions.
Difficulties with the clinical definition of apraxia persist, as for the agnosias.
For example, ‘dressing apraxia’ and ‘constructional apraxia’ are now considered
visuospatial problems rather than true apraxias. Likewise, some cases labelled
as eyelid apraxia or gait apraxia are not true ideational apraxias. The exact
nosological status of speech apraxia also remains tendentious.
What is Aprosexia?
Aprosexia is a syndrome of psychomotor inefficiency, characterized by complaints of easy forgetting, for example, of conversations as soon as they are
finished, material just read, or instructions just given. There is difficulty keeping the mind on a specific task, which is forgotten if the patient happens to be
distracted by another task. These difficulties, into which the patient has insight
and often bitterly complains of, are commonly encountered in the memory clinic.
They probably represent a disturbance of attention or concentration, rather than
being a harbinger of dementia. These patients generally achieve normal scores
on formal psychometric tests (and indeed may complain that these assessments
do not test the function they are having difficulty with). Concurrent sleep disturbance, irritability, and low mood are common and may reflect an underlying affective disorder (anxiety, depression) which may merit specific treatment.
What is Aprosodia, Aprosody?
Aprosodia or aprosody (dysprosodia, dysprosody) is a defect in or absence of the
ability to produce or comprehend speech melody, intonation, cadence, rhythm,
and accentuations, in other words the non-linguistic aspects of language which
convey or imply emotion and attitude. Aprosodia may be classified, in a manner
analogous to the aphasias, as:
• Sensory (posterior):
Impaired comprehension of the emotional overtones of spoken language or emotional gesturing, also known as affective agnosia; this
may be associated with visual extinction and anosognosia, reflecting
right posterior temporoparietal region pathology.
• Expressive/motor (anterior):
An inability to produce emotional overtones (‘emotional dysprosody’,
sometimes confusingly referred to as speech dyspraxia); this may occur
in isolation with right-sided anterior lesions or in association with
linguistic aspects of aphasia such as agrammatism with anterior left
hemisphere damage.
What is Arcuate Scotoma?
An arcuate scotoma suggests retinal or optic nerve disease, such as glaucoma,
acute ischaemic optic neuropathy, or the presence of drusen.
What is Areflexia?
Areflexia is an absence or a loss of tendon reflexes. This may be physiological, in
that some individuals never demonstrate tendon reflexes; or pathological, reflecting an anatomical interruption or physiological dysfunction at any point along
the monosynaptic reflex pathway which is the neuroanatomical substrate of phasic stretch reflexes. Sudden tendon stretch, as produced by a sharp blow from a tendon hammer, activates muscle spindle Ia afferents which pass to the ventral horn of the spinal cord, there activating α-motor neurones, the efferent limb of the reflex, so completing the monosynaptic arc. Hence, although reflexes are typically regarded as part of the examination of the motor system, reflex loss may
also occur in ‘sensory’ disorders, affecting the Ia afferents from the muscle spindle. It is often possible to ‘hear’ that reflexes are absent from the thud of tendon hammer on tendon.
Areflexia is most often encountered in disorders of lower motor neurones,
specifically, radiculopathies, plexopathies, and neuropathies (axonal and demyelinating). Areflexia may also occur in neuromuscular junction disorders, such as
the Lambert–Eaton myasthenic syndrome, in which condition the reflexes may
be ‘restored’ following forced muscular contraction (facilitation). Transient areflexia may be seen in central nervous system disorders, such as cataplexy, and
in acute spinal cord syndromes (‘spinal shock’, e.g. acute compression, acute
inflammatory myelopathy).
What is Argyll Robertson Pupil (ARP)?
The Argyll Robertson pupil is small (miosis) and irregular. It fails to react to
light (reflex iridoplegia), but does constrict to accommodation (when the eyes
converge). In other words, there is light-near pupillary dissociation (ARP =
accommodation reaction preserved). Since the light reflex is lost, testing for the
accommodation reaction may be performed with the pupil directly illuminated:
this can make it easier to see the response to accommodation, which is often difficult to observe when the pupil is small or in individuals with a dark iris. There
may be an incomplete response to mydriatic drugs. Although pupil involvement
is usually bilateral, it is often asymmetric, causing anisocoria.
The Argyll Robertson pupil was originally described in the context of neurosyphilis, especially tabes dorsalis. If this pathological diagnosis is suspected,
a helpful clinical concomitant is the associated loss of deep pain sensation, as
assessed, for example, by vigorously squeezing the Achilles tendon (Abadie’s
sign). There are, however, a number of recognized causes of ARP besides
neurosyphilis, including
• Multiple sclerosis;
• Encephalitis;
• Diabetes mellitus;
• Syringobulbia;
• Sarcoidosis;
• Lyme disease;
• Pinealoma;
• Herpes zoster;
• Hereditary motor and sensory neuropathies (Charcot–Marie Tooth disease;
Dejerine–Sottas hypertrophic neuropathy).
Miosis and pupil irregularity are inconstant findings in some of these situations, in which case the term ‘pseudo-Argyll Robertson pupil’ may be preferred.
The neuroanatomical substrate of the Argyll Robertson pupil is uncertain.
A lesion in the tectum of the (rostral) midbrain proximal to the oculomotor
nuclei have been suggested. In multiple sclerosis and sarcoidosis, magnetic resonance imaging has shown lesions in the periaqueductal grey matter at the level
of the Edinger–Westphal nucleus, but these cases lacked miosis and may therefore be classified as pseudo-Argyll Robertson pupil. Some authorities think that
a partial oculomotor (III) nerve palsy or a lesion of the ciliary ganglion is a more
likely cause.
What is Arm Drop?
‘Arm drop’, or the ‘face–hand test’, has been suggested as a useful diagnostic
test if hemiparesis or upper limb monoparesis is suspected to be psychogenic: the
examiner lifts the paretic hand directly over the patient’s face and drops it. It is
said that in organic weakness the hand will hit the face, whereas patients with
functional weakness avoid this consequence. However, the validity and reliability
of this ‘avoidance testing manoeuvre’ has never been examined; its clinical value
is therefore doubtful.
What is Asemasia?
Asemasia is an inability to indicate by signs or spoken language. The term was
invented in the nineteenth century (Hamilton) as an alternative to aphasia, since
in many cases of the latter there is more than a loss of speech, including impaired
pantomime (apraxia) and in symbolizing the relationships of things
What is Asomatognosia?
Asomatognosia is a lack of regard for a part, or parts, of the body, most typically
failure to acknowledge the existence of a hemiplegic left arm. Asomatognosia
may be verbal (denial of limb ownership) or non-verbal (failure to dress or
wash limb). All patients with asomatognosia have hemispatial neglect (usually
left), hence this would seem to be a precondition for the development of asomatognosia; indeed, for some authorities asomatognosia is synonymous with
personal neglect. Attribution of the neglected limb to another person is known as
somatoparaphrenia.
The neuroanatomical correlate of asomatognosia is damage to the right
supramarginal gyrus and posterior corona radiata, most commonly due to
a cerebrovascular event. Cases with right thalamic lesions have also been
reported. The predilection of asomatognosia for the left side of the body
may simply be a reflection of the aphasic problems associated with left sided lesions that might be expected to produce asomatognosia for the right side. Asomatognosia is related to anosognosia (unawareness or denial of illness) but the two are dissociable on clinical and experimental grounds. Some authorities consider asomatognosia as a form of confabulation.
What is Astasia–Abasia?
Astasia–abasia is the name which has sometimes been given to a disorder of gait
characterized by impaired balance (disequilibrium), wide base, shortened stride,
start/turn hesitation, and freezing. The term has no standardized definition and
hence may mean different things to different observers; it has also been used
to describe a disorder characterized by inability to stand or walk despite normal leg strength when lying or sitting, believed to be psychogenic (although gait
apraxia may have similar features). Modern clinical classifications of gait disorders subsume astasia–abasia under the categories of subcortical disequilibrium
and frontal disequilibrium, i.e. gait disorders with prominent disequilibrium or
impaired postural control. A transient inability to sit or stand despite normal
limb strength may be seen after an acute thalamic lesion (thalamic astasia).
What is Astereognosis?
Astereognosis is the failure to recognize a familiar object, such as a key or a coin,
palpated in the hand with the eyes closed, despite intact primary sensory modalities. Description of qualities such as the size, shape, and texture of the object
may be possible. Hence, this is a failure of higher-order (i.e. cortical) processing
and is associated with lesions of the posterior parietal lobe (postcentral gyrus)
association cortex. There may be associated impairments of two-point discrimination and graphaesthesia (cortical sensory syndrome). Astereognosis was said
to be invariably present in the original description of the thalamic syndrome by
Dejerine and Roussy.
Some authorities recommend the terms stereoanaesthesia or stereohypaesthesia as more appropriate descriptors of this phenomenon, to emphasize that
this may be a disorder of perception rather than a true agnosia (for a similar
debate in the visual domain, see Dysmorphopsia).
What is Asterixis?
Asterixis is a sudden, brief, arrhythmic lapse of sustained posture due to involuntary interruption in muscle contraction. It is most easily demonstrated by observing the dorsiflexed hands with arms outstretched (i.e. the motion to indicate
‘stop’), lapses being seen as flicking or flapping movements of the hands (‘flapping tremor’). Movement is associated with EMG silence in antigravity muscles
for 35–200 ms. These features distinguish asterixis from tremor and myoclonus;
the phenomenon has previously been described as negative myoclonus or negative tremor. Asterixis may be bilateral or unilateral. Recognized causes of
asterixis include
• Hepatic encephalopathy (‘liver flap’);
• Hypercapnia;
• Uraemia;
• Drug-induced, e.g. anticonvulsants, levodopa;
• Structural brain lesions: thalamic lesions (haemorrhage, thalamotomy).
Unilateral asterixis has been described in the context of stroke, contralateral
to lesions of the midbrain (involving corticospinal fibres, medial lemniscus), thalamus (ventroposterolateral nucleus), primary motor cortex, and parietal lobe;
and ipsilateral to lesions of the pons or medulla.
What is Asthenopia?
Asthenopia, literally ‘weak vision’, is frequently used to describe ‘eye strain’
due to uncorrected or incorrectly corrected refractive errors, such as hyperopia
(far-sightedness) or overcorrected myopia. Such refractive errors are sometimes
blamed for headache.
What is Asynergia?
Asynergia or dyssynergia is lack or impairment of synergy of sequential muscular
contraction in the performance of complex movements, such that they seem to
become broken up into their constituent parts, so-called decomposition of movement. This may be evident when performing rapid alternating hand movements.
Dyssynergy of speech may also occur, a phenomenon sometimes termed scanning speech or scanning dysarthria. This is typically seen in cerebellar syndromes,
most often those affecting the cerebellar hemispheres, and may coexist with other
signs of cerebellar disease such as ataxia, dysmetria, and dysdiadochokinesia.
What is Ataxia?
Ataxia or dystaxia refers to a lack of coordination of voluntary motor acts,
impairing their smooth performance. The rate, range, timing, direction, and
force of movement may be affected. Ataxia is used most frequently to refer to
a cerebellar problem, but sensory ataxia, optic ataxia, and frontal ataxia are also
described, so it is probably best to qualify ataxia rather than to use the word in
isolation.
• Cerebellar ataxia:
Defective timing of agonist and antagonist muscle contraction (asynergia) produces jerking, staggering, inaccurate movements (decomposition of movement), which may manifest as intention tremor, dysmetria (past pointing), dysdiadochokinesia, ataxic dysarthria (sometimes
known as scanning speech, although this also has other connotations), excessive rebound phenomenon, macrographia, head tremor
(titubation), gait ataxia, and abnormal eye movements (nystagmus,
square wave jerks, saccadic intrusions). There may be concurrent limb
hypotonia. Cerebellar hemisphere lesions cause ipsilateral limb ataxia
(hemiataxia; ataxia on finger-to-nose, finger chase, and/or heel–shin
testing) whereas midline cerebellar lesions involving the vermis produce
selective truncal and gait ataxia. An International Cooperative Ataxia
Rating Scale has been developed to assess the efficacy of treatments for
cerebellar ataxia.
• Sensory ataxia:
Results from impaired proprioception and may be seen in disease of the
dorsal (posterior) columns of the spinal cord (hence ‘spinal ataxia’),
sensory neuropathies, and neuronopathies affecting the dorsal root
ganglia. It is markedly exacerbated by removal of visual cues (e.g. as
in Romberg’s sign), unlike the situation with cerebellar ataxia, and may
also lead to pseudoathetosis.
• Optic ataxia:
Mis reaching for visually presented targets, with dysmetria, due to a
parieto-occipital lesion, as seen in Balint’s syndrome.
• ‘Frontal ataxia’:
Similar to, and sometimes indistinguishable from, cerebellar ataxia, but
results from lesions of the contralateral frontal cortex or frontopontine
fibres, often from tumours invading the frontal lobe or corpus callosum. These fibres run in the corticopontocerebellar tract, synapsing in
the pons before passing through the middle cerebellar peduncle to the
contralateral cerebellar hemisphere.
Triple ataxia, the rare concurrence of cerebellar, sensory, and optic types of
ataxia, may be associated with an alien limb phenomenon (sensory type).
There are many causes of cerebellar ataxia, including
• Inherited:
Autosomal recessive: Friedreich’s ataxia, ataxia with isolated vitamin E
deficiency, ataxia with oculomotor apraxia (types 1 and 2);
Autosomal dominant: clinically ADCA types I, II, and III, now reclassified genetically as spinocerebellar ataxias: types 1–31 now described;
Episodic ataxias: channelopathies involving potassium (type 1) and
calcium (type 2) ion channels;
Mitochondrial disorders;
Huntington’s disease;
Dentatorubropallidoluysian atrophy (DRPLA);
Inherited prion diseases, especially Gerstmann–Straussler–Scheinker
(GSS) syndrome.
• Acquired:
Cerebrovascular events (infarct, haemorrhage): usually cause hemiataxia; postanoxic cerebellar ataxia;
Inflammatory: demyelination: multiple sclerosis, Miller Fisher variant of Guillain–Barré syndrome, central pontine and extrapontine
myelinolysis;
Inflammatory: infection: cerebellitis with Epstein–Barr virus; encephalitis with Mycoplasma; HIV;
Neoplasia: tumours, paraneoplastic syndromes;
Neurodegeneration: one variant of multiple system atrophy (MSA-C);
prion diseases (Brownell–Oppenheimer variant of sporadic
Creutzfeldt–Jakob disease, kuru); idiopathic late-onset cerebellar
ataxia;
Drugs/toxins, e.g. alcohol, phenytoin.
Metabolic: vitamin E deficiency, thiamine deficiency (Wernicke’s
encephalopathy), gluten ataxia, hypothyroidism (debatable).
Ataxic Hemiparesis
Ataxic hemiparesis is a syndrome of ipsilateral hemiataxia and hemiparesis, the
latter affecting the leg more severely than the arm (crural paresis). There may be
additional dysarthria, nystagmus, paraesthesia, and pain.
This syndrome is caused by lacunar (small deep) infarcts in the contralateral
basis pons at the junction of the upper third and lower two-thirds. It may also be
seen with infarcts in the contralateral thalamocapsular region, posterior limb of
the internal capsule (anterior choroidal artery syndrome), red nucleus, and the
paracentral region (anterior cerebral artery territory). Sensory loss is an indicator of capsular involvement; pain in the absence of other sensory features is an
indicator of thalamic involvement.
What is Athetosis?
Athetosis is the name sometimes given to an involuntary movement disorder
characterized by slow, sinuous, purposeless, writhing movements, often more
evident in the distal part of the limbs. Athetosis often coexists with the more
flowing, dance-like movements of chorea, in which case the movement disorder may be described as choreoathetosis. Indeed, the term athetosis is now
little used except in the context of ‘athetoid cerebral palsy’. Athetoid-like movements of the outstretched hands may also be seen in the presence of sensory
ataxia (impaired proprioception) and are known as pseudoathetosis or pseudo choreoathetosis. Choreoathetoid movements result from disorders of the basal ganglia.
What is Athymhormia?
Athym(h)ormia, also known as the robot syndrome, is a name given to a form of
abulia or akinetic mutism in which there is loss of self-autoactivation. Clinically
there is a marked discrepancy between heteroactivation, behaviour under the
influence of exogenous stimulation, which is normal or almost normal, and
autoactivation. Left alone, patients are akinetic and mute, a state also known as
loss of psychic self-activation or pure psychic akinesia. It is associated with bilateral deep lesions of the frontal white matter or of the basal ganglia, especially
the globus pallidus. Athymhormia is thus environment-dependent, patients normalizing initiation and cognition when stimulated, an important differentiation from apathy and akinetic mutism.
What is atrophy?
Atrophy is a wasting or thinning of tissues. The term is often applied to wasted
muscles, usually in the context of lower motor neurone pathology (in which case
it may be synonymous with amyotrophy), but also with disuse. Atrophy develops
more quickly after lower, as opposed to upper, motor neurone lesions. It may also
be applied to other tissues, such as subcutaneous tissue (as in hemifacial atrophy).
Atrophy may sometimes be remote from the affected part of the neuraxis, hence a
false-localizing sign, for example, wasting of intrinsic hand muscles with foramen
magnum lesions.
What is ‘Attended Alone’ Sign?
Collateral history is crucial in assessing cognitive disorders, especially complaints
of memory impairment, for which reason individuals referred to memory clinics
are usually asked to bring with them a spouse, relative, or friend who knows them
well to provide such history. Failure to attend with an informant, the ‘attended
alone’ sign, is a robust (i.e. very sensitive, > 0.95) marker of the absence of
dementia.
What is Attention?
Attention is a distributed cognitive function, important for the operation of
many other cognitive domains; the terms concentration, vigilance, and persistence may be used synonymously with attention. Distinction may be made
between different types of attention, as follows:
• Sustained;
• Selective;
• Divided/executive function.
It is generally accepted that attention is effortful, selective, and closely linked
to intention.
Impairment of attentional mechanisms may lead to distractability (with a
resulting complaint of poor memory, perhaps better termed aprosexia), disorientation in time and place, perceptual problems, and behavioural problems (e.g.
disinhibition), as in the cardinal disorder of attention, delirium.
The neuroanatomical substrates of attention encompass the ascending reticular activating system of the brainstem, the thalamus, and the prefrontal (multimodal association) cerebral cortex (especially on the right). Damage to any of
these areas may cause impaired attention.
Attentional mechanisms may be tested in a variety of ways. Those adapted
to ‘bedside’ use all essentially look for a defect in selective attention, also known
as working memory or short-term memory (although this does not necessarily
equate with lay use of the term ‘short-term memory’):
• Orientation in time/place;
• Digit span forwards/backwards;
• Reciting months of the year backwards, counting back from 30 to 1;
• Serial sevens (serial subtraction of 7 from 100, = 93, 86, 79, 72, 65).
In the presence of severe attentional disorder (as in delirium) it is difficult to make any meaningful assessment of other cognitive domains (e.g. memory).
Besides delirium, attentional impairments may be seen following head injury,
and in ostensibly ‘alert’ patients, e.g. with Alzheimer’s disease (the dysexecutive
syndrome of impaired divided attention).
What is Auditory Agnosia?
Auditory agnosia refers to an inability to appreciate the meaning of sounds
despite normal perception of pure tones as assessed by audiological examination.
This agnosia may be for either verbal material (pure word deafness) or nonverbal material, either sounds (bells, whistles, animal noises) or music (amusia, of receptive or sensory type).
What is Auditory–Visual Synaesthesia?
This name has been given to the phenomenon of sudden sound-evoked light
flashes in patients with optic nerve disorders. This may be equivalent to noise induced visual phosphenes or sound-induced photisms. It is not certain that this phenomenon meets suggested criteria for synaesthesia.
What is Augmentation?
The term augmentation may be used to describe a phenomenon seen in Lambert–
Eaton myasthenic syndrome (LEMS), namely, an increase in strength of affected
muscles detected in the first few seconds of maximal voluntary contraction, one
feature, along with facilitation, of post tetanic potentiation. This may also be
known as Lambert’s sign.
Augmentation also refers to the paradoxical worsening of the symptoms
of restless legs syndrome with dopaminergic treatment, manifesting with earlier
onset of symptoms in the evening or afternoon, shorter periods of rest to provoke
symptoms, greater intensity of symptoms when they occur, spread of symptoms
to other body parts such as the arms, and decreased duration of benefit from
medication.
What is Aura?
An aura is a brief feeling or sensation, lasting seconds to minutes, occurring
immediately before the onset of a paroxysmal neurological event such as an
epileptic seizure or a migraine attack (migraine with aura, ‘classical migraine’),
‘warning’ of its imminent presentation, although auras may also occur in isolation. An aura indicates the focal onset of neurological dysfunction. Auras
are exclusively subjective, and may be entirely sensory, such as the fortification spectra (teichopsia) of migraine, or more complex, labelled psychosensory
or experiential, as in certain seizures. Epileptic auras may be classified into
subgroups:
• Somatosensory:
for example, paraesthesia;
• Visual:
hallucinations, illusions; occipital, or temporal origin; complex hallucinations and a ‘tunnel vision’ phenomenon are exclusive to seizures
of anteromedial temporal and occipitotemporal origin, whereas elementary hallucinations, illusions, and visual loss are common to both
occipital and temporal lobe seizures;
• Auditory:
may indicate an origin in the superior temporal gyrus;
• Olfactory:
parosmia may occur in seizures of medial temporal lobe origin (uncus;
uncinate fits);
• Gustatory;
• Autonomic;
• Abdominal:
rising epigastric sensation (visceral aura) of temporal lobe epilepsy;
• Psychic:
complex hallucinations or illusions that usually affect different senses,
e.g. distortions of familiarity such as deja vu or jamais vu auras of
focal-onset epilepsy, indicative of temporal lobe and limbic onset, respectively.
What is Automatic Obedience?
Automatic obedience may be seen in startle syndromes such as the jumping Frenchmen of Maine, latah, and myriachit, when a sudden shout of, for
example, ‘jump’ is followed by a jump. These are sometimes known as the
startle-automatic obedience syndromes. Although initially classified (by Gilles de la Tourette) with tic syndromes, there are clear clinical and pathophysiological differences.
Automatic Writing Behaviour
Automatic writing behaviour is a form of increased writing activity. It has been
suggested that it should refer specifically to a permanently present or elicitable,
compulsive, iterative and not necessarily complete, written reproduction of visually or orally perceived messages (cf. hypergraphia). This is characterized as
a particular, sometimes isolated, form of utilization behaviour in which the
inhibitory functions of the frontal lobes are suppressed.
What is Automatism?
Automatisms are complex motor movements occurring in complex motor
seizures, which resemble natural movements but occur in an inappropriate setting. These may occur during a state of impaired consciousness during or shortly
after an epileptic seizure. There is usually amnesia for the event.
Automatisms occur in about one-third of patients with complex partial
seizures, most commonly those of temporal or frontal lobe origin. Although
there are qualitative differences between the automatisms seen in seizures arising
from these sites, they are not of sufficient specificity to be of reliable diagnostic
value; bizarre automatisms are more likely to be frontal.
Automatisms may take various forms:
• Oro-facial movements:
for example, lip smacking, chewing and swallowing movements, salivation (especially temporal lobe origin).
• Gestural:
hand fumbling, foot shuffling, tidying, or more complex actions such
as undressing; upper limb movements are said to be more suggestive of temporal lobe origin, lower limb movements (kicking, cycling)
of frontal lobe origin; pelvic thrusting (may also be seen in pseudo seizures).
• Ambulatory:
walking or running around (cursive seizures); prolonged wandering
may be termed fugue or poriomania.
• Emotional:
laughing and, more rarely, crying (gelastic and dacrystic seizures,
respectively, although crying may also be a feature of non-epileptic
seizures), fear, anger.
• Verbal:
humming, whistling, grunting, speaking incoherently; vocalization is
common in frontal lobe automatisms.
Automatic behaviour and fugue-like states may also occur in the context of
narcolepsy and must be differentiated from the automatisms of complex partial
seizures on the basis of history, examination, and EEG.
What is Autophony?
The perception of the reverberation of one’s own voice, which occurs with
external or middle, but not inner, ear disease.
What is Autoscopy?
Autoscopy (literally ‘seeing oneself’) is a visual hallucination of one’s own face,
sometimes with upper body or entire body, likened to seeing oneself in a mirror
(hence mirror hallucination). The hallucinated image is a mirror image, i.e. shows
left–right reversal as in a mirror image. Unlike heautoscopy, there is a coincidence
of egocentric and body-centred perspectives. Autoscopy may be associated with
parieto-occipital space-occupying lesions, epilepsy, and migraine.
What is Autotopagnosia?
Autotopagnosia, or somatotopagnosia, is a rare disorder of body schema characterized by inability to identify parts of the body, either to verbal command or by
imitation; this is sometimes localized but at worst involves all parts of the body.
This may be a form of category-specific anomia with maximum difficulty for
naming body parts or one feature of anosognosia. Finger agnosia and right–left
disorientation are partial forms of autotopagnosia, all of which are most often
seen following cerebrovascular events involving the left parietal area.
What is Babinski’s Sign (1)?
Babinski’s sign is a polysynaptic cutaneous reflex consisting of an extensor
movement (dorsiflexion) of the big toe on eliciting the plantar response, due
to contraction of extensor hallucis longus. There may be in addition fanning
(abduction) of the other toes (fan sign; signe de l’éventail) but this is neither
necessary nor sufficient for Babinski’s sign to be judged present. There may be
simultaneous contraction of other limb flexor muscles, consistent with the notion
that Babinski’s sign forms part of a flexion synergy (withdrawal) of the leg. The
use of the term ‘negative Babinski sign’ to indicate the normal finding of a down going (flexor; plantar flexion) big toe is incorrect, ‘flexor plantar response’ being
the appropriate description. The plantar response is most commonly performed
by stroking the sole of the foot, although many other variants are described (e.g.
Chaddock’s sign, Gordon’s sign, Oppenheim’s sign).
Babinski’s sign is a normal finding in infants with immature (unmyelinated)
corticospinal tracts; persistence beyond 3 years of age, or re-emergence in adult
life, is pathological. In this context, Babinski’s sign is considered a reliable (‘hard’)
sign of corticospinal (pyramidal) tract dysfunction (upper motor neurone pathology) and may coexist with other signs of upper motor neurone dysfunction
(e.g. weakness in a so-called pyramidal distribution, spasticity, hyperreflexia).
However, if weakness of extensor hallucis longus is one of the features of upper
motor neurone dysfunction, or from any other cause, Babinski’s sign may be
unexpectedly absent although anticipated on clinical grounds. Other causes of
Babinski’s sign includes hepatic coma, post epileptic seizure, deep sleep following
prolonged induced wakefulness, and cataplectic attack, hence it is not necessarily
a consequence of a permanent and irreversible lesion of the pyramidal tracts.
In the presence of extrapyramidal signs, it is important to distinguish
Babinski’s sign, a ‘pyramidal sign’, from a striatal toe (spontaneous up going
plantar).
What is Babinski’s Sign (2)?
Babinski (1905) described the paradoxical elevation of the eyebrow in hemifacial spasm as orbicularis oris contracts and the eye closes, a synkinesis which is not reproducible by will. This observation indicated to Babinski the peripheral (facial nerve) origin of hemifacial spasm. It may assist in differentiating hemifacial spasm from other craniofacial movement disorders.
What is Babinski’s Trunk–Thigh Test?
Babinski’s trunk–thigh test, also known as the ‘rising sign’, is suggested to be
of use in distinguishing organic from functional paraplegia and hemiplegia (the
abductor sign may also be of use in the former case, Hoover’s sign in the latter).
The recumbent patient is asked to sit up with the arms folded on the front of the
chest. In organic hemiplegia there is involuntary flexion of the paretic leg, which
may automatically rise higher than the normal leg; in paraplegia both legs are
involuntarily raised. In functional paraplegic weakness neither leg is raised, and
in functional hemiplegia only the normal leg is raised.
What is Balaclava Helmet?
A pattern of facial sensory loss resembling in distribution a balaclava helmet,
involving the outer parts of the face but sparing the nose and mouth, may be seen
with central brainstem lesions such as syringobulbia which progress upwards
from the neck, such that the lowermost part of the spinal nucleus of the trigeminal nerve which serves the outer part of the face is involved whilst the upper part
of the nucleus which serves the central part of the face is spared. This pattern of
facial sensory impairment may also be known as onion peel or onion skin.
What is Oppenheim’s sign?
Oppenheim’s sign is dorsiflexion of the great toe elicited by irritation downward of the medial side of the tibia. It is one of a number of Babinski-like responses. The sign’s presence indicates a damage to the pyramidal tract. It is named for Hermann Oppenheim. ^ Swartz, Mark H.
What is Schaeffer’s sign?
Schaeffer’s sign is an extensor plantar reflex occurring while squeezing the Achillian tendon; Oppenheim’s sign can be obtained by scratching downward the medial side of the tibia; Gordon’s sign comes from squeezing the muscles in the calf; all of the three signs result in the dorsiflexion of the big toe in pyramidal tract dysfunctions (PTD).
What is Chaddock’s sign?
Chaddock’s sign is present when stroking of the lateral malleolus causes extension of the great toe, indicating damage to the corticospinal tract. It was identified by Charles Gilbert Chaddock in 1911.
What is Balint’s Syndrome?
Balint’s syndrome, first described by a Hungarian neurologist in 1909, consists of:
• Simultanagnosia (q.v.; dorsal type):
A constriction of visual attention, such that the patient is aware of
only one object at a time; visual acuity is preserved, and patients can
recognize single objects placed directly in front of them; they are unable
to read or distinguish overlapping figures.
• Spatial disorientation:
Loss of spatial reference and memory, leaving the patient ‘lost in space’.
• Disorders of oculomotor function:
Specifically, visually guided eye movements (fixation, pursuit, saccades); Balint’s ‘psychic paralysis of gaze’, or ‘sticky fixation’, refers
to an inability to direct voluntary eye movements to visual targets,
despite a full range of eye movements; this has also been characterized as a form of oculomotor apraxia. Accurate eye movements may
be programmed by sound or touch. Loss of spontaneous blinking has
also been reported.
• Optic ataxia:
A failure to grasp or touch an object under visual guidance.
Not all elements may be present; there may also be coexisting visual field
defects, hemispatial neglect, visual agnosia, or prosopagnosia.
Balint’s syndrome results from bilateral lesions of the parieto-occipital junction causing a functional disconnection between higher-order visual cortical
regions and the frontal eye fields, with sparing of the primary visual cortex.
Brain imaging, either structural (CT, MRI) or functional (SPECT, PET), may
demonstrate this bilateral damage, which is usually of vascular origin, for example, due to watershed or border zone ischaemia or top-of-the-basilar syndrome.
Balint syndrome has also been reported as a migrainous phenomenon, following
traumatic brain injury and in association with Alzheimer’s disease, brain tumour
(butterfly glioma), radiation necrosis, progressive multifocal leucoencephalopathy, Marchiafava–Bignami disease with pathology affecting the corpus callosum, and X-linked adrenoleucodystrophy.
What is Ballism, Ballismus?
Ballism or ballismus is a hyperkinetic involuntary movement disorder characterized by wild, flinging, throwing movements of a limb. These movements
most usually involve one-half of the body (hemiballismus), although they may
sometimes involve a single extremity (monoballismus) or both halves of the
body (paraballismus). The movements are often continuous during wakefulness
but cease during sleep. Hemiballismus may be associated with limb hypotonia.
Clinical and pathophysiological studies suggest that ballism is a severe form
of chorea. It is most commonly associated with lesions of the contralateral
subthalamic nucleus.
What is Battle’s Sign?
Battle’s sign is a haematoma overlying the mastoid process, which indicates
an underlying basilar skull fracture extending into the mastoid portion of the
temporal bone. It appears 48–72 h after the trauma which causes the fracture.
What is Beevor’s Sign?
Beevor’s sign is an upward movement of the umbilicus in a supine patient
attempting either to flex the head onto the chest against resistance (e.g. the examiner’s hand) or performing a sit-up. It indicates a lesion causing rectus abdominis
muscle weakness below the umbilicus. This may occur with a spinal lesion (e.g.
tumour, syringomyelia) between T10 and T12 causing isolated weakness of the
lower part of the muscle, or myopathies affecting abdominal muscles, particularly
facioscapulohumeral muscular dystrophy. Lower cutaneous abdominal reflexes
are also absent, having the same localizing value.
Downward movement of the umbilicus (‘inverted Beevor’s sign’) due to
weakness of the upper part of rectus abdominis is less often seen.
What is Belle Indifférence?
La belle indifférence refers to a patient’s seeming lack of concern in the presence
of serious symptoms. This was first defined in the context of ‘hysteria’, along
with exaggerated emotional reactions, what might now be termed functional or
somatoform illness. However, the sign is a poor discriminator against ‘organic’
illness. Some patients’ coping style is to make light of serious symptoms; they
might be labelled stoical.
Patients with neuropathological lesions may also demonstrate a lack of
concern for their disabilities, either due to a disorder of body schema (anosodiaphoria) or due to incongruence of mood (typically in frontal lobe syndromes, sometimes seen in multiple sclerosis).
What is Macrographia?
Macrographia is abnormally large handwriting. It may be seen in cerebellar
disease, possibly as a reflection of the kinetic tremor and/or the impaired
checking response seen therein (cf. micrographia).
What is Macropsia?
Macropsia, or ‘Brobdingnagian sight’, is an illusory phenomenon in which the
size of a normally recognized object is overestimated.
What is SWJ?
Both the more common square wave jerks (SWJ) and the rare macro square wave jerks are horizontal saccadic intrusions with a normal intersaccadic interval; these two saccadic intrusions differ from each other concerning their size: SWJ are less than 5 degrees, while macro square wave jerks are greater than 5 degrees.
What is Metamorphopsia?
It is a visual defect that causes linear objects, such as lines on a grid, to look curvy or rounded. It’s caused by problems with the eye’s retina, and, in particular, the macula.
What is macrosomatognosia?
There is a hallucination called “macrosomatognosia” which is the perception that one’s own body parts feel bigger than they actually are. Likewise, “microsomatognosia”is feeling that one’s own body parts feel smaller than they actually are.
What is Macula Sparing, Macula Splitting?
Macula sparing is a feature of a homonymous hemianopia in which central vision
is intact, due to damage confined to the occipital cortex without involving the
occipital pole. This may occur because anastomoses between the middle and posterior cerebral arteries maintain that part of area 17 necessary for central vision
after occlusion of the posterior cerebral artery.
Cortical blindness due to bilateral (sequential or simultaneous) posterior
cerebral artery occlusion may leave a small central field around the fixation point
intact, also known as macula sparing.
Macula splitting, a homonymous hemianopia which cuts through the vertical meridian of the macula, occurs with lesions of the optic radiation.
Hence, macula sparing and macula splitting have localizing value when
assessing homonymous hemianopia.
What is Maculopathy?
Maculopathy is any process affecting the macula, with changes observable on
ophthalmoscopy. These processes may produce a central or ring scotoma and
visual failure. Common causes include
• Diabetes mellitus: oedema and hard exudates at the macula are a common
cause of visual impairment, especially in non-insulin-dependent diabetes
mellitus.
• Hypertension: abnormal vascular permeability around the fovea may produce a macular star.
• Drug-induced: e.g. ‘bull’s-eye’ maculopathy of chloroquine.
• ‘Cherry red spot at the macula’: this appearance may occur in sialidosis
(‘cherry red spot–myoclonus syndrome’) and gangliosidoses (e.g. Tay–Sachs
disease).
What is a cherry red spot in the eye?
The retina is a lining of tissue located at the back of the eye, which helps to transmit visual information to the brain. A patient suffering from retinal artery occlusion may have a cherry-red spot in the macula. Adults with a cherry-red spot have typically either suffered an injury to the eye or suffer from impaired circulation in the area.
What is Magnetic Movements?
Movements may be described as magnetic in varying contexts:
• the following or tracking movements of an alien hand in corticobasal degeneration, reaching out to touch or grasp the examiner’s hand or clothing, as
in forced groping; also known as compulsive tactile exploration;
• in a hesitant gait (ignition failure), with seeming inability to lift the feet
(‘stuck to the floor’) in gait apraxia.
What is Main d’accoucheur?
Main d’accoucheur, or carpopedal spasm, is a posture of the hand with wrist
flexion in which the muscles are rigid and painful. Main d’accoucheur is so called
because of its resemblance to the posture of the hand adopted for the manual
delivery of a baby (‘obstetrical hand’).
This tetanic posture may develop in acute hypocalcaemia (induced by
hyperventilation, for instance) or hypomagnesaemia and reflects muscle hyperexcitability. Development of main d’accoucheur within 4 min of inflation of a sphygmomanometer cuff above arterial pressure (Trousseau’s sign) indicates latent
tetany. Mechanosensitivity of nerves may also be present elsewhere (Chvostek’s
sign).
What is Main Succulente?
Main succulente refers to a swollen hand with thickened subcutaneous tissues,
hyperkeratosis and cyanosis, and trophic changes which may be observed in an
analgesic hand, e.g. in syringomyelia.
What is Man-in-a-Barrel?
‘Man-in-a-barrel’ is a clinical syndrome of brachial diplegia with preservation of brainstem function and of muscle strength in the legs. This most usually occurs as a result of bilateral border zone infarcts in the territories between the anterior and middle cerebral arteries (‘watershed infarction’).
This may be as a consequence of cerebral hypoperfusion (e.g. during cardiac
arrest, cardiac surgery), in which case the prognosis is poor. The clinical picture has also been reported with cerebral metastases. Acute central cervical cord
lesions may also produce a ‘man-in-a-barrel’ syndrome, for example, after severe
hyperextension injury or after unilateral vertebral artery dissection causing anterior cervical spinal cord infarction. This may follow a transient quadriplegia, and considerable recovery is possible.
A neurogenic man-in-a-barrel syndrome has been reported (‘flail arm syndrome’), which is a variant of motor neurone disease. Likewise, bilateral neuralgic amyotrophy can produce an acute peripheral man-in-a-barrel phenotype.
What is Marche à Petit Pas?
Marche à petit pas is a disorder of gait characterized by impairments of balance,
gait ignition, and locomotion. Particularly there is shortened stride (literally
marche à petit pas) and a variably wide base. This gait disorder is often associated
with dementia, frontal release signs, and urinary incontinence, and sometimes
with apraxia, parkinsonism, and pyramidal signs. This constellation of clinical
signs reflects underlying pathology in the frontal lobe and subjacent white matter,
most usually of vascular origin, and is often associated with a subcortical vascular dementia. Modern clinical classifications of gait disorders have subsumed marche à petit pas into the category of frontal gait disorder.
What are Charcot joints?
Any pathology that leads to loss of sensation in a joint may lead to a Charcot joint: 1. Classically, Charcot joints in the lower limb were most often the result of tabes dorsalis but that is much rarer these days. 2. The most common cause is diabetic neuropathy and diabetes is increasing in prevalence. 3. In the upper limb the classical cause is syringomyelia. Diabetic neuropathy is common in developed countries where diabetes is common but in developing countries, tabes dorsalis and leprosy.
What is Marcus Gunn Pupil, Marcus Gunn Sign?
The Marcus Gunn pupil or sign, first described in 1902 by the ophthalmologist
Robert Marcus Gunn, is the adaptation of the pupillary light reflex to persistent
light stimulation, that is, a dilatation of the pupil is observed with continuing
stimulation with incident light (‘dynamic anisocoria’). This is indicative of an
afferent pathway defect, such as retrobulbar neuritis. The swinging flashlight sign
or test may be used to demonstrate this by comparing direct and consensual
pupillary light reflexes in one eye. Normally the responses are equal but in the
presence of an afferent conduction defect an inequality is manifest as pupillary
dilatation.
What is Mask-Like Facies?
The poverty of spontaneous facial expression, hypomimia, seen in extrapyramidal disorders such as idiopathic Parkinson’s disease is sometimes described as mask-like.
What is Masseter Hypertrophy?
Masseter hypertrophy, either unilateral or bilateral, may occur in individuals
prone to bruxism. A familial syndrome of hypertrophy of the masseter muscles
has been described.
What is Masticatory Claudication?
Pain in the muscles of mastication with chewing may be a sign, along with
headache, of giant cell (temporal) arteritis.
What is McArdle’s Sign?
McArdle’s sign is the combination of reduced lower limb strength, increased
lower limb stiffness, and impaired mobility following neck flexion. The difference may best be appreciated by comparing leg strength (e.g. hip flexion) with
the neck fully extended and fully flexed.
The sign was initially described in multiple sclerosis but may occur in other
myelopathies affecting the cord at any point between the foramen magnum and
the lower thoracic region. The mechanism is presumed to be stretch-induced
conduction block, due to demyelinated plaques or other pathologies, in the corticospinal tracts. McArdle’s sign may be envisaged as the motor equivalent of Lhermitte’s sign.
What is Medial Medullary Syndrome?
The medial medullary syndrome, or Dejerine’s anterior bulbar syndrome, results
from damage to the medial medulla, most usually infarction as a consequence of
anterior spinal artery or vertebral artery occlusion. The clinical picture is of:
• Ipsilateral tongue paresis and atrophy, fasciculations (hypoglossal nerve
involvement);
• Contralateral hemiplegia with sparing of the face (pyramid);
• Contralateral loss of position and vibration sense (medial lemniscus) with
pain and temperature sensation spared;
• +/− upbeat nystagmus
What is a menace response?
The menace response is one of three forms of blink reflex. It is the reflex blinking that occurs in response to the rapid approach of an object. The reflex comprises blinking of the eyelids, in order to protect the eyes from potential damage, but may also including turning of the head, neck, or even the trunk away from the optical stimulus that triggers the reflex. A menace response is not well elicited from the lateral retina, as a menace gesture originating on the medial side of the eye is typically blocked by the patient’s nose. A menace response is elicited by a threatening hand gesture heading towards the eye.
What is Meningism?
Meningism (meningismus, nuchal rigidity) is a stiffness or discomfort on passive
movement (especially flexion) of the neck in the presence of meningeal irritation (e.g. infective meningitis, subarachnoid haemorrhage). A number of other,
eponymous, signs of meningeal irritation have been described, of which the best
known are those of Kernig and Brudzinski.
Meningism is not synonymous with meningitis, since it may occur in
acute systemic pyrexial illnesses (pneumonia, bronchitis), especially in children.
Moreover, meningism may be absent despite the presence of meningitis in the
elderly and those receiving immunosuppression.
What is Metamorphopsia?
Metamorphopsia is an illusory visual phenomenon characterized by objects
appearing distorted or misshapen in form. As with neglect, these phenomena
may be classified as object- or person-centred:
• Object-centred: affecting size and spatial relationships.
Macropsia: objects appear larger than normal.
Micropsia: objects appear smaller than normal.
Pelopsia: objects appear closer to the observer than actual.
Porropsia: objects appear farther away from the observer than actual.
• Person-centred:
Microsomatognosia and macrosomatognosia: body image appears
smaller or larger than normal (‘Alice in Wonderland’ syndrome).
Metamorphopsias are often transient and episodic, occurring, for example, during migraine attacks, epileptic seizures, with psychotropic drug abuse,
and following petechial intraparenchymal haemorrhages. Rarely, they are long-lasting or permanent, for example, following brain infarction (most commonly
involving the occipito-parietal or temporoparietal cortex: lesions on the right are
more likely than those on the left to give metamorphopsia) or tumours. Retinal
disease causing displacement of photoreceptors may produce metamorphopsia:
micropsia due to receptor separation in retinal oedema, macropsia due to receptor approximation in retinal scarring. Occasional cases of metamorphopsia have
been reported with lesions of the optic chiasm, optic radiation, and retro splenial region. Indeed, it seems that metamorphopsia may occur with pathology at
any point along the visual pathway from retina to cortex. Differing patterns of
metamorphopsia may assist with clinico-anatomical correlation:
• retinal lesions: ipsilateral monocular;
• chiasmal lesions: bitemporal;
• occipitoparietal lesions: contralateral homonymous.
Metamorphopsia may be associated with visual hallucinations.
What is Telopsia?
Sometimes the term * porropsia is used as a synonym, although phenomenologically the two symptoms are not identical (porropsia being defined as a condition in which stationary objects are perceived as receding into the distance). Nor should teleopsia be confused with * micropsia, a visual distortion in which objects and stimuli are perceived as smaller, but not necessarily as further away.
What is Micrographia?
Micrographia is small handwriting. It is most often recognized in association
with the extrapyramidal features of idiopathic Parkinson’s disease (indeed it may
be the presenting sign), but may occasionally occur with other parkinsonian
syndromes (e.g. progressive supranuclear palsy [PSP]) or in isolation with focal
lesions of the midbrain or basal ganglia.
In Parkinson’s disease, handwriting may initially be of normal size but then
becomes progressively smaller, slower, and more illegible as writing proceeds, an
example of parkinsonian fatigue, a gradual decline in the amplitude and speed
of initiation of voluntary movements. Such ‘slow’ micrographia may be distinguished from ‘fast’ micrographia in which letters are small throughout although
written at normal speed without fatigue, which may be seen in PSP or other
pallidal pathologies.
There is a poor correlation between micrographia and the side, severity,
or duration of classical parkinsonian features, and its response to levodopa
preparations is very variable. These observations, along with reports of isolated
micrographia with cortical lesions demonstrated by neuroimaging, suggest that
the anatomical basis of micrographia may be at the level of the cortex (dominant
parietal lobe) rather than the basal ganglia.
Micrographia has also been described following large right anterior cerebral artery infarcts and lacunar infarcts involving the putamen and genu of
the internal capsule. Isolated micrographia has been reported with lenticular
haematoma.
What is Micropsia?
Micropsia, or ‘Lilliput sight’, is an illusory phenomenon in which the size of
a normally recognized object is underestimated. It is the most common form
of metamorphopsia and is most often associated with lesions of the right temporoparietal cortex, although macular oedema and optic chiasm lesions may also
cause micropsia. In migraine transient micropsia may occur. Hemimicropsia,
What is Macula Sparing, Macula Splitting?
Macula sparing is a feature of a homonymous hemianopia in which central vision
is intact, due to damage confined to the occipital cortex without involving the
occipital pole. This may occur because anastomoses between the middle and posterior cerebral arteries maintain that part of area 17 necessary for central vision
after occlusion of the posterior cerebral artery.
Cortical blindness due to bilateral (sequential or simultaneous) posterior
cerebral artery occlusion may leave a small central field around the fixation point
intact, also known as macula sparing.
Macula splitting, a homonymous hemianopia which cuts through the vertical meridian of the macula, occurs with lesions of the optic radiation.
Hence, macula sparing and macula splitting have localizing value when
assessing homonymous hemianopia.
What is Maculopathy?
Maculopathy is any process affecting the macula, with changes observable on
ophthalmoscopy. These processes may produce a central or ring scotoma and
visual failure. Common causes include
• Diabetes mellitus: oedema and hard exudates at the macula are a common
cause of visual impairment, especially in non-insulin-dependent diabetes
mellitus.
• Hypertension: abnormal vascular permeability around the fovea may produce a macular star.
• Drug-induced: e.g. ‘bull’s-eye’ maculopathy of chloroquine.
• ‘Cherry red spot at the macula’: this appearance may occur in sialidosis
(‘cherry red spot–myoclonus syndrome’) and gangliosidoses (e.g. Tay–Sachs
disease).
What is Magnetic Movements?
Movements may be described as magnetic in varying contexts:
• the following or tracking movements of an alien hand in corticobasal degeneration, reaching out to touch or grasp the examiner’s hand or clothing, as in forced groping; also known as compulsive tactile exploration;
• in a hesitant gait (ignition failure), with seeming inability to lift the feet
(‘stuck to the floor’) in gait apraxia.
What is Main d’accoucheur?
Main d’accoucheur, or carpopedal spasm, is a posture of the hand with wrist
flexion in which the muscles are rigid and painful. Main d’accoucheur is so called
because of its resemblance to the posture of the hand adopted for the manual
delivery of a baby (‘obstetrical hand’).
This tetanic posture may develop in acute hypocalcaemia (induced by
hyperventilation, for instance) or hypomagnesaemia and reflects muscle hyperexcitability. Development of main d’accoucheur within 4 min of inflation of a sphygmomanometer cuff above arterial pressure (Trousseau’s sign) indicates latent
tetany. Mechanosensitivity of nerves may also be present elsewhere (Chvostek’s
sign).
What is Main Succulente?
Main succulente refers to a swollen hand with thickened subcutaneous tissues,
hyperkeratosis and cyanosis, and trophic changes which may be observed in an
analgesic hand, e.g. in syringomyelia.
What is Man-in-a-Barrel?
‘Man-in-a-barrel’ is a clinical syndrome of brachial diplegia with preservation of
brainstem function and of muscle strength in the legs.
This most usually occurs as a result of bilateral border zone infarcts in the territories between the anterior and middle cerebral arteries (‘watershed infarction’).
This may be as a consequence of cerebral hypoperfusion (e.g. during cardiac
arrest, cardiac surgery), in which case the prognosis is poor. The clinical picture has also been reported with cerebral metastases. Acute central cervical cord
lesions may also produce a ‘man-in-a-barrel’ syndrome, for example, after severe
hyperextension injury or after unilateral vertebral artery dissection causing anterior cervical spinal cord infarction. This may follow a transient quadriplegia, and considerable recovery is possible.
A neurogenic man-in-a-barrel syndrome has been reported (‘flail arm syndrome’), which is a variant of motor neurone disease. Likewise, bilateral neuralgic amyotrophy can produce an acute peripheral man-in-a-barrel phenotype.
What is Marche à Petit Pas?
Marche à petit pas is a disorder of gait characterized by impairments of balance,
gait ignition, and locomotion. Particularly there is shortened stride (literally
marche à petit pas) and a variably wide base. This gait disorder is often associated
with dementia, frontal release signs, and urinary incontinence, and sometimes
with apraxia, parkinsonism, and pyramidal signs. This constellation of clinical
signs reflects underlying pathology in the frontal lobe and subjacent white matter,
most usually of vascular origin, and is often associated with a subcortical vascular dementia. Modern clinical classifications of gait disorders have subsumed
marche à petit pas into the category of frontal gait disorder.
What is Marcus Gunn Pupil, Marcus Gunn Sign?
The Marcus Gunn pupil or sign, first described in 1902 by the ophthalmologist
Robert Marcus Gunn, is the adaptation of the pupillary light reflex to persistent
light stimulation, that is, a dilatation of the pupil is observed with continuing
stimulation with incident light (‘dynamic anisocoria’). This is indicative of an
afferent pathway defect, such as retrobulbar neuritis. The swinging flashlight sign
or test may be used to demonstrate this by comparing direct and consensual
pupillary light reflexes in one eye. Normally the responses are equal but in the
presence of an afferent conduction defect an inequality is manifest as pupillary
dilatation.
What is Mask-Like Facies?
The poverty of spontaneous facial expression, hypomimia, seen in extrapyramidal disorders such as idiopathic Parkinson’s disease is sometimes described as mask-like.
What is Masseter Hypertrophy?
Masseter hypertrophy, either unilateral or bilateral, may occur in individuals
prone to bruxism. A familial syndrome of hypertrophy of the masseter muscles
has been described.
What is Masticatory Claudication?
Pain in the muscles of mastication with chewing may be a sign, along with
headache, of giant cell (temporal) arteritis.
What is McArdle’s Sign?
McArdle’s sign is the combination of reduced lower limb strength, increased
lower limb stiffness, and impaired mobility following neck flexion. The difference may best be appreciated by comparing leg strength (e.g. hip flexion) with
the neck fully extended and fully flexed.
The sign was initially described in multiple sclerosis but may occur in other
myelopathies affecting the cord at any point between the foramen magnum and
the lower thoracic region. The mechanism is presumed to be stretch-induced
conduction block, due to demyelinated plaques or other pathologies, in the corticospinal tracts. McArdle’s sign may be envisaged as the motor equivalent of Lhermitte’s sign.
What is Medial Medullary Syndrome?
The medial medullary syndrome, or Dejerine’s anterior bulbar syndrome, results
from damage to the medial medulla, most usually infarction as a consequence of
anterior spinal artery or vertebral artery occlusion. The clinical picture is of:
• Ipsilateral tongue paresis and atrophy, fasciculations (hypoglossal nerve
involvement);
• Contralateral hemiplegia with sparing of the face (pyramid);
• Contralateral loss of position and vibration sense (medial lemniscus) with
pain and temperature sensation spared;
• +/− upbeat nystagmus
What is Meningism?
Meningism (meningismus, nuchal rigidity) is a stiffness or discomfort on passive
movement (especially flexion) of the neck in the presence of meningeal irritation (e.g. infective meningitis, subarachnoid haemorrhage). A number of other,
eponymous, signs of meningeal irritation have been described, of which the best
known are those of Kernig and Brudzinski.
Meningism is not synonymous with meningitis, since it may occur in
acute systemic pyrexial illnesses (pneumonia, bronchitis), especially in children.
Moreover, meningism may be absent despite the presence of meningitis in the
elderly and those receiving immunosuppression.
What is Metamorphopsia?
Metamorphopsia is an illusory visual phenomenon characterized by objects
appearing distorted or misshapen in form. As with neglect, these phenomena
may be classified as object- or person-centred:
• Object-centred: affecting size and spatial relationships.
Macropsia: objects appear larger than normal.
Micropsia: objects appear smaller than normal.
Pelopsia: objects appear closer to the observer than actual.
Porropsia: objects appear farther away from the observer than actual.
• Person-centred:
Microsomatognosia and macrosomatognosia: body image appears
smaller or larger than normal (‘Alice in Wonderland’ syndrome).
Metamorphopsias are often transient and episodic, occurring, for example, during migraine attacks, epileptic seizures, with psychotropic drug abuse,
and following petechial intraparenchymal haemorrhages. Rarely, they are long-lasting or permanent, for example, following brain infarction (most commonly
involving the occipito-parietal or temporoparietal cortex: lesions on the right are
more likely than those on the left to give metamorphopsia) or tumours. Retinal
disease causing displacement of photoreceptors may produce metamorphopsia:
micropsia due to receptor separation in retinal oedema, macropsia due to receptor approximation in retinal scarring. Occasional cases of metamorphopsia have
been reported with lesions of the optic chiasm, optic radiation, and retro splenial region. Indeed, it seems that metamorphopsia may occur with pathology at
any point along the visual pathway from retina to cortex. Differing patterns of
metamorphopsia may assist with clinico-anatomical correlation:
• retinal lesions: ipsilateral monocular;
• chiasmal lesions: bitemporal;
• occipitoparietal lesions: contralateral homonymous.
Metamorphopsia may be associated with visual hallucinations.
What is Micrographia?
Micrographia is small handwriting. It is most often recognized in association
with the extrapyramidal features of idiopathic Parkinson’s disease (indeed it may
be the presenting sign), but may occasionally occur with other parkinsonian
syndromes (e.g. progressive supranuclear palsy [PSP]) or in isolation with focal
lesions of the midbrain or basal ganglia.
In Parkinson’s disease, handwriting may initially be of normal size but then
becomes progressively smaller, slower, and more illegible as writing proceeds, an
example of parkinsonian fatigue, a gradual decline in the amplitude and speed
of initiation of voluntary movements. Such ‘slow’ micrographia may be distinguished from ‘fast’ micrographia in which letters are small throughout although
written at normal speed without fatigue, which may be seen in PSP or other
pallidal pathologies.
There is a poor correlation between micrographia and the side, severity,
or duration of classical parkinsonian features, and its response to levodopa
preparations is very variable. These observations, along with reports of isolated
micrographia with cortical lesions demonstrated by neuroimaging, suggest that
the anatomical basis of micrographia may be at the level of the cortex (dominant
parietal lobe) rather than the basal ganglia.
Micrographia has also been described following large right anterior cerebral artery infarcts and lacunar infarcts involving the putamen and genu of
the internal capsule. Isolated micrographia has been reported with lenticular
haematoma.
What is Micropsia?
Micropsia, or ‘Lilliput sight’, is an illusory phenomenon in which the size of
a normally recognized object is underestimated. It is the most common form
of metamorphopsia and is most often associated with lesions of the right temporoparietal cortex, although macular oedema and optic chiasm lesions may also
cause micropsia. In migraine transient micropsia may occur. Hemimicropsia,
micropsia confined to one visual hemifield, has been recorded. The entirely
subjective nature of the disorder may account for the relative rarity of reports.
What is Milkmaid’s Grip?
Milkmaid’s grip is the descriptive term applied to the inability to maintain a
firm grip (e.g. of the examiner’s fingers), detected as an alternating squeezing
and releasing (as required for successful milking by hand). Seen in Huntington’s
disease, this may reflect a combination of chorea and motor impersistence.
What is motor impersistence?
The inability to maintain postures or positions (such as keeping eyes closed, protruding the tongue, maintaining conjugate gaze steadily in a fixed direction, or making a prolonged ‘ah’ sound) without repeated prompts.
What is Miosis?
Miosis is abnormal reduction in pupillary size, which may be unilateral or
bilateral.
Causes include
• Oculosympathetic paresis of whatever cause, e.g. Horner’s syndrome (unilateral), pontine haemorrhage (bilateral), early stages of central cephalic
herniation (bilateral);
• Drug-induced: e.g. opiates (bilateral);
• Pupils tend to be small and reactive in metabolic-toxic encephalopathies
(bilateral);
• ‘Senile miosis’ (bilateral): age-related.
If only one pupil appears small (anisocoria), it is important to distinguish
miosis from contralateral mydriasis, when a different differential will apply.
Age-related signs; Anisocoria; Argyll Robertson pupil; Horner’s syndrome;
What is Mirror Agnosia?
Mirror agnosia, or the ‘looking glass syndrome’, is a phenomenon observed in
patients with left hemispatial neglect as a result of right parietal lobe lesions.
There is inability to point to objects seen in a mirror, with repeated reaching
‘into’ the mirror even when the actual location of the target is shown. In a milder
form, known as ‘mirror ataxia’, patients reach in the direction of the object but
with increased errors of reach and grasp, suggesting that visual information is
not adequately transformed into a body-centred frame of reference.
What is Mirror Apraxia?
Patients with mirror apraxia presented with an object that can be seen only in a
mirror, when asked to reach for the real object will reach for the virtual object
in the mirror. Mirror apraxia results from right or left posterior parietal lobe
lesions.
What is Mirror Movements?
Mirror movements are involuntary movements of one side of the body that
accompany and ‘mirror’ (reflect) intentional movements on the opposite side
of the body (also known as imitation synkinesis). They are usually symmetrical
and most often seen when using distal muscles of the upper limb. Mirror movements are frequently present in young children but prevalence decreases with age.
Persistence of mirror movements into adult life (‘congenital mirror movements’)
is pathological, as is acquisition in adult life. These movements are uncommon after acquired brain lesions with no relationship to specific anatomical areas.
Congenital mirror movements are associated with skeletal developmental
abnormalities, especially of the atlanto-occipital region, such as Klippel–Feil syndrome. They are also seen in 85% of patients with X-linked Kallmann syndrome
(hypogonadotrophic hypogonadism and anosmia).
Acquired mirror movements have been described following thalamic
lesions, and in association with spastic paraparesis, extrapyramidal disorders
(Parkinson’s disease, multiple system atrophy), Friedriech’s ataxia, phenylketonuria, and affecting hemiparetic limbs following stroke in young children.
There is some neurophysiological evidence from patients with X-linked
Kallmann syndrome for the existence of an ipsilateral corticospinal pathway,
consistent with other evidence that the congenital condition is primarily a
disorder of axonal guidance during development. Concurrent activity within
ipsilateral and contralateral corticospinal pathways may explain mirroring of
movements. Alternatively, a failure of transcallosal inhibition, acquired at the
time of myelination of these pathways, may contribute to the genesis of mirror
movements. Loss of joint position sense following thalamic lesions may be of relevance. A deficit of sustained attention has also been postulated as the cause of
mirror movements.
What is Mirror Sign?
The term ‘mirror sign’ has been applied to the phenomenon of misrecognition of self as another when seen in a mirror. It may be classified with the delusional misidentification syndromes. This may occur in Alzheimer’s disease and frontotemporal dementia and is associated with impaired cognition, confabulation, and prefrontal dysfunction. It may lead to a patient complaint of an intruder or a stranger living in the house (‘phantom boarder’ syndrome). Failure to recognize oneself in a mirror may also be a dissociative symptom, a symptom of depersonalization. Some authors believe ‘the phenomenon of the mirror’ to be an extreme example of prosopagnosia, but other studies have not found an association.
What is Delusional misidentification syndrome?
Delusional misidentification syndrome is an umbrella term, introduced by Christodoulou (in his book The Delusional Misidentification Syndromes, Karger, Basel, 1986) for a group of delusional disorders that occur in the context of mental and neurological illness. They all involve a belief that the identity of a person, object, or place has somehow changed or has been altered. As these delusions typically only concern one particular topic, they also fall under the category called monothematic delusions.
This psychopathological syndrome is usually considered to include four main variants
The Capgras delusion is the belief that (usually) a close relative or spouse has been replaced by an identical-looking impostor.
The Fregoli delusion is the belief that various people the believer meets are actually the same person in disguise.
Intermetamorphosis is the belief that an individual has the ability to take the form of another person in both external appearance and internal personality.
Subjective doubles, described by Christodoulou in 1978 (American Journal of Psychiatry 135, 249, 1978), is the belief that there is a doppelgänger or double of him- or herself carrying out independent actions
However, similar delusional beliefs, often singularly or more rarely reported, are sometimes also considered to be part of the delusional misidentification syndrome. For example:
Mirrored-self misidentification is the belief that one’s reflection in a mirror is some other person.
Reduplicative paramnesia is the belief that a familiar person, place, object, or body part has been duplicated. For example, a person may believe that they are in fact not in the hospital to which they were admitted, but an identical-looking hospital in a different part of the country, despite this being obviously false.
The Cotard delusion is a rare disorder in which people hold a delusional belief that they are dead (either figuratively or literally), do not exist, are putrefying, or have lost their blood or internal organs. In rare instances, it can include delusions of immortality.
Syndrome of delusional companions is the belief that objects (such as soft toys) are sentient beings.
Clonal pluralization of the self, where a person believes there are multiple copies of him- or herself, identical both physically and psychologically but physically separate and distinct.
There is considerable evidence that disorders such as the Capgras or Fregoli syndromes are associated with disorders of face perception and recognition. However, it has been suggested that all misidentification problems exist on a continuum of anomalies of familiarity, from déjà vu at one end to the formation of delusional beliefs at the other.
What is Mirror Writing?
As the name implies, mirror writing is a mirror image of normal writing, hence running from right to left, with characters back to front. This may occur spontaneously, apparently more often in left-handers, or in right-handers attempting to write with the left hand following left-sided brain injury (e.g. stroke).
Leonardo da Vinci (1452–1519) is the most celebrated mirror writer: it is possible his left-handedness, and hence mirror writing, followed an injury to his right hand. The author Lewis Carroll occasionally wrote mirror letters but these differ from his normal script, unlike the situation with Leonardo whose two scripts are faithful mirror images. Carroll’s letters may thus reflect not an inherent capacity but a contrivance, designed to amuse children who corresponded with him.
The device was also used by the author Arthur Ransome in his 1939 novel Secret
Water. Jane Austen wrote one letter (1817) to a young niece in which script runs
from right to left but with word order reversed within words (i.e. not mirror writing).
What is the specific brain area associated with prosopagnosia?
The specific brain area usually associated with prosopagnosia is the fusiform gyrus, which activates specifically in response to faces. The functionality of the fusiform gyrus allows most people to recognize faces in more detail than they do similarly complex inanimate objects.
What is Misidentification Syndromes?
These are defined as delusional conditions in which patients incorrectly identify
and reduplicate people, places, objects, or events. Examples include
• Capgras syndrome; may be related to reduplicative paramnesia
• Fregoli syndrome
• Intermetamorphosis
• Phantom boarder sign
• Mirror sign
What is Misoplegia?
Misoplegia is a disorder of body schema in which there is active hatred of a paralyzed limb, with or without personification of the limb, and attempts to injure
the paralyzed limb. It occurs with right parietal region injury (hence left-sided
limbs most often involved) and may occur in conjunction with anosognosia, left
hemispatial neglect, and (so called) constructional apraxia.
What is Mitgehen?
An abnormality of induced movement, in which limb movement occurs in
response to application of the slightest pressure despite the patient having been
told to resist (German: to go too); a manifestation of negativism.
What is Mitmachen?
A motor disorder in which the patient acquiesces to every passive movement of
the body made by the examiner, but as soon as the examiner releases the body
part, the patient returns it to the resting position.
What is Monoballismus?
Monoballismus is ballism affecting a single limb.
What is Negativism?
It is a well-established psychopathologic reaction signifying the negativistic behavior of patients with schizophrenia to stimuli from the environment (outer negativism), as well as to impulses from within (inner negativism). It was first described by Kahlbaum as the motor negativism which is seen in patients with catatonia.
What is Monochromatopsia?
The author has seen a patient with a diagnosis of frontotemporal dementia who
persistently and consistently complained that everything he saw was red, even
though he was aware that they were not red, for example, his wife’s grey hair.
His speech was fluent without paraphasia although impoverished in content,
with recurrent themes repeated almost verbatim. He had mild oro-facial dyspraxia. There was no alexia. Confronted with objects of different colours, he was
unable to point to them by colour since all appeared red to him. The features
seem to be distinct from erythropsia (persistent) or phantom chromatopsia (normal visual acuity). The author proposes that this phenomenon might be termed ‘monochromatopsia’.
What is Monoparesis, Monoplegia?
Monoparesis is weakness, monoplegia complete weakness (‘paralysis’), of a single limb. Monoparesis of the arm or leg of upper motor neurone type is usually
cortical in origin, although may unusually arise from a cord lesion (leg more
frequently than arm). Hoover’s sign and Babinski’s trunk–thigh test may be helpful in deciding whether monoparetic/monoplegic leg weakness is of non-organic
origin, and the ‘arm drop’ or ‘face–hand test’ in arm weakness.
Peripheral disorders can sometimes present exclusively with single limb
weakness, such as monomelic motor neurone disease (Hirayama disease), multifocal motor neuropathy with conduction block, and Guillain–Barré syndrome.
What is mononeuropathy multiplex?
Mononeuropathy multiplex is the most specific manifestation of vasculitic neuropathy, and is often referred to as mononeuritis multiplex. The typical presentation is acute or subacute onset of multifocal mononeuropathies with weakness, sensory loss, and pain.
What is Monophasia?
It is recurring utterances, verbal stereotypy Neurology A form of motor aphasia, characterized by stereotyped utterances repeatedly repeated, as if by compulsion; an involuntary compulsion to perform a motor act Associations Psychomotor epilepsy, catatonic schizophrenia, psychogenic fugue, complex partial seizure, post-traumatic automatism, etc.
What is Monotonia?
Monotonia is a restricted range of speech inflection, occurring with hypophonia
as part of the hypokinetic dysarthria observed in parkinsonism.
What is Moria?
Moria is literally folly (as in Desiderius Erasmus’ Moriae Encomium of 1509,
literally ‘praise of folly’). In clinical usage, the meaning overlaps not only with
that of emotional lability but has also been used in the context of pathological
What is Motor Neglect?
Motor neglect is failure to move the contralesional limbs in the neglect syndrome,
a more severe impairment than directional hypokinesia.
What is directional hypokinesia?
Spatial hemineglect may be explained in terms of defective organisation of movements towards the left half-space (directional hypokinesia). The frontal lesion of the patient may be the neural correlate of this selective disorder. Hypokinesia refers to decreased bodily movement. One of the two categories of movement disorders, hypokinesia is characterized by a partial or complete loss of muscle movement due to a disruption in the basal ganglia. Patients with hypokinetic disorders like Parkinson’s disease experience muscle rigidity and an inability to produce movement. It is also associated with mental health disorders and prolonged inactivity due to illness, amongst other diseases.
What is Eastchester clapping sign?
A 63-year-old right-handed man with known right carotid artery occlusion developed acute left arm weakness. When asked to clap his hands, he brought the right hand to midline and stopped
What is Moving Ear?
A focal dyskinesia characterized by ear movement has been described.
What is Muscle Hypertrophy?
Muscle hypertrophy is muscle enlargement due to an increase in the size of
its myofibrils. Muscle hypertrophy may be generalized or focal and occurs in
response to repetitive voluntary contraction (physiological) or repetitive abnormal electrical activity (pathological, e.g. myotonia in Thomsen’s disease; primary
orthostatic tremor). Muscle enlargement may also result from replacement of
myofibrils by other tissues such as fat or amyloid, a situation better described as
pseudohypertrophy.
What is Mutism?
Mutism is absence of speech output. This may be psychogenic, as in schizophrenia or affective disorders, with or without catatonia; or a consequence of neurological disease, for example:
• Akinetic mutism;
• Dementia syndromes, especially frontal lobe dementia, late stages of primary non-fluent aphasia;
• Encephalopathy (toxic/drug-induced/metabolic);
• Damage to Broca’s area, supplementary motor area; severe pseudobulbar
palsy, bilateral thalamic damage;
• Cerebellar mutism: rare, following midline cerebellar surgery in children.
Thought to be due to dentato thalamocortical tract damage, bilateral
oedema in cerebellar peduncles (rather than surgical trauma or infarction);
• Bilateral vocal cord paralysis (although this may be better termed aphonia);
• Autism.
In neurological disorders there may be difficulty initiating movements,
completing motor sequences, or inhibition of appropriate responses.
What is Myasthenic Snarl?
Patients with weakness of facial musculature as a consequence of myasthenia
gravis may have a ‘transverse smile’, with lack of elevation of the corners of
the mouth, or appear to snarl when asked to smile or laugh. This may give the
impression that they seem peculiarly unamused by an examiner’s attempted witticisms. These phenomena may be seen with other causes of facial weakness, such as facioscapulohumeral (FSH) dystrophy.
What is Mydriasis?
Mydriasis is an abnormal dilatation of the pupil, either unilateral or bilateral.
Causes include
• Oculoparasympathetic paresis, from lesions at the Edinger–Westphal
nucleus or anywhere along the course of the oculomotor (III) nerve (usually
unilateral);
• Tonic enlargement of the pupil (Holmes–Adie pupil, usually unilateral);
• Sympathomimetic drugs, e.g. adrenaline (usually bilateral);
• Later stages of central cephalic herniation;
• A syndrome of benign episodic unilateral mydriasis has been described,
sometimes related to migraine.
If only one pupil appears large (anisocoria), it is important to distinguish
mydriasis from contralateral miosis, when a different differential will apply (e.g.
Horner’s syndrome).
What is Myelopathy?
A myelopathy is a disorder of the spinal cord. Such disorders may be further
characterized according to whether the responsible lesion lies within or outside
the spinal cord: intrinsic or intramedullary lesions are always intradural; extrinsic
or extramedullary lesions may be intradural or extradural. It may be possible
to differentiate intramedullary from extramedullary lesions on clinical grounds,
although this distinction is never absolute because of clinical overlap.
Clinical features of extrinsic/extramedullary myelopathy:
• Motor: sequential spastic paraparesis below the level of the lesion; upper
motor neurone (UMN) signs occur early; lower motor neurone (LMN) signs
are unusual and have a segmental (radicular) distribution if present.
• Sensory: symptoms of pain may be radicular (e.g. secondary to a neurofibroma) or vertebral (e.g. secondary to neoplastic or inflammatory processes); sensory signs are not usually marked until the later stages, and all
modalities are often involved. A Brown–Séquard syndrome may be more
common in extrinsic than intrinsic myelopathies.
• Sphincters: may have bladder urgency, impotence.
Pathologies commonly causing extrinsic myelopathy include
• prolapsed disc, osteophyte bar;
• tumour (primary, secondary);
• arteriovenous malformation/haematoma;
• abscess.
Clinical features of intrinsic/intramedullary myelopathy:
• Motor: LMN signs may be prominent and diffuse; UMN signs tend to occur
late (spastic paraparesis below level of lesion). A combination of UMN and
LMN signs is much more likely to reflect intrinsic than extrinsic pathology.
• Sensory: symptoms of central (funicular) pain may occur; dissociated sensory loss (spinothalamic > dorsal column involvement, or vice versa), suspended sensory loss, and sacral sparing are characteristic of intramedullary
lesions; a Brown–Séquard syndrome may occur. Vibratory sensibility is more
often affected than proprioception.
• Sphincters: bladder involvement common, often early and slow to recover.
These features are dependent on the extent to which the cord is involved:
some pathologies have a predilection for posterior columns, central cord, etc.
Pathologies commonly causing intrinsic myelopathy include
• multiple sclerosis or other inflammatory process causing transverse myelitis
(complete or partial), e.g. viral infection, HTLV-1 infection, tabes dorsalis;
• tumour (primary, secondary);
• syringomyelia;
• infarction, e.g. anterior spinal artery syndrome;
• metabolic causes: vitamin B12 deficiency producing subacute combined
degeneration of the cord.
Imaging of the cord, ideally with MRI, may be helpful in defining the cause
of myelopathy.
What is glabellar tap sign?
Myerson’s sign or glabellar tap sign is a medical condition where a patient is unable to resist blinking when tapped on the glabella, the area above the nose and between the eyebrows. It is often referred to as the glabellar reflex. It is often an early symptom of Parkinson’s disease, but can also be seen in early dementia as well as other progressive neurologic illness.
What is Myoclonus?
Myoclonus is involuntary, ‘shock-like’, muscle jerking, arrhythmic more often
than regular, of central nervous system (CNS) origin. This may be focal, multifocal, or generalized. Multiple irregular asynchronous myoclonic jerks may be termed polymyoclonus. Myoclonus may be characterized in several ways:
• Clinical classification (by observation, examination):
Spontaneous
Action or intention: following voluntary action; may be elicited by
asking patient to reach out to touch the examiner’s hand
Reflex, stimulus-sensitive: jerks produced by somaesthetic stimulation
of a limb, in response to loud noises
• Anatomical/pathophysiological classification (by electrophysiological recordings):
Cortical
Subcortical/reticular
Propriospinal/segmental
• Aetiological classification:
Physiological, e.g. ‘sleep starts’ (hypnic jerks)
Essential: in the absence of any other abnormality of the CNS
Epileptic: as a manifestation of idiopathic epilepsy
Symptomatic: of other neurological diseases, of which there are many,
including
Anoxic brain injury (Lance–Adams syndrome)
Cerebrovascular lesions
Neoplasia
Encephalopathies: especially of metabolic origin (hepatic, renal), but
also toxic, viral, paraneoplastic, mitochondrial
Degenerations: basal ganglia, spinocerebellar
Malabsorption syndromes: coeliac disease, Whipple’s disease
Storage disorders, e.g. Lafora body disease, Tay–Sachs disease, sialidosis
Dementias: Alzheimer’s disease (usually late), prion disease (usually
early in sporadic Creutzfeldt–Jakob disease); not seen in frontotemporal lobar degenerations
Inherited disorders: myoclonus–dystonia syndrome (DYT11)
The clinical differential diagnosis of myoclonus includes chorea, tic, tremor
(especially with rhythmic myoclonus), and certain peripheral nerve disorders
(fasciculation, myokymia). Periodic limb movement disorder or periodic leg
movements of sleep, frequently found in association with restless legs syndrome,
is sometimes called ‘nocturnal myoclonus’. Brief lapses of muscle contraction
with loss of posture are in some ways the converse of myoclonus and have in
the past been labelled ‘negative myoclonus’, although the term asterixis is now
preferred.
Drugs useful in the treatment of myoclonus include clonazepam, sodium valproate, primidone, and piracetam. These may need to be given in combination to suppress severe action myoclonus.
What is Jactitation?
Jactitation refers to sexual arousal or excitement derived from discussing their own sexual exploits.
What is Myoedema?
Myoedema, or muscle mounding, provoked by mechanical stimuli or stretching
of muscle, is a feature of rippling muscle disease, in which the muscle contractions
are associated with electrical silence. It has also been reported as a neuromuscular
feature of hypothyroidism.
What is Myokymia?
Myokymia is an involuntary, spontaneous, wave-like, undulating, flickering
movement within a muscle (cf. fasciculation); it may be likened to a ‘bag of
worms’. Neurophysiologically this corresponds to regular groups of motor unit
discharges of peripheral nerve origin. Myokymia is thus related to neuromyotonia and stiffness, since there may be concurrent impairment of muscle relaxation
and a complaint of muscle cramps.
A syndrome of superior oblique myokymia is described, often following
superior oblique palsy, which produces a microtremor of the eye and causes oscillopsia or transient diplopia. Facial myokymia is a rare facial dyskinesia, possibly
related to disinhibition of the facial (VII) nerve nucleus by focal pontine lesions
(tumour, demyelination).
Neurophysiological evidence of myokymia may be helpful in the assessment of a brachial plexopathy, since this is found in radiation-induced, but not neoplastic, lesions.
What is Myopathy?
The term myopathy means a primary disorder of muscle causing wasting and/or
weakness in the absence of sensory abnormalities. Clinically, myopathic processes need to be differentiated from neuropathies, particularly anterior horn
cell diseases and motor neuropathies, and neuromuscular junction disorders.
Generally, in primary muscle disease there are no fasciculations, reflexes are lost
late, and phenomena such as (peripheral) fatigue and facilitation do not occur.
Myopathies may be subdivided according to the clinical pattern of weakness,
and/or their aetiology:
• Proximal:
Affecting shoulder abductors, hip flexors predominantly:
Inflammatory: polymyositis, dermatomyositis
Progressive muscular dystrophies: Duchenne, Becker, limb-girdle,
facioscapulohumeral (FSH)
Metabolic: acid maltase deficiency; thyroid dysfunction, Cushing’s
syndrome
Non-metastatic feature of malignant disease
• Distal:
An unusual pattern for myopathy, which needs to be differentiated from
distal polyneuropathy:
Myotonic dystrophy
Miyoshi dystrophy
Desmin myopathy
• Bulbar palsy
• Facial paresis
• Diaphragm weakness:
Acid maltase deficiency
Acute polymyositis
Neuralgic amyotrophy
• Axial myopathy:
Camptocormia (‘bent spine syndrome’)
Dropped head syndrome
What is Myorhythmia?
Myorhythmia is an involuntary movement disorder characterized by rhythmic
contraction (1–3 Hz) of muscles producing a coarse tremor, which may affect
limbs, face, palate, head, jaw, neck, tongue, eyes, or trunk. The movements
are continuous and persist during sleep. They are associated with brainstem or
thalamic vascular disease, trauma, alcohol-related nutritional deficiency, phenytoin intoxication, Hashimoto’s encephalopathy, paraneoplasia, and Whipple’s disease.
Although very rare, Oculomasticatory myorhythmia is of diagnostic importance since it is pathognomonic for Whipple’s disease of the nervous system. Characteristically there is also convergent–divergent pendular nystagmus
with synchronous rhythmic movement of the mouth, tongue, jaw, and sometimes proximal and distal skeletal muscles. The neurological manifestations of Whipple’s disease are protean, and include dementia, ataxia, supranuclear ophthalmoplegia (with sparing of the pupils), epileptic seizures, myoclonus, nystagmus, and psychosis. The condition is caused by the bacterium Tropheryma whipplei. Treatment is with antibiotics, usually a 2-week intravenous course of trimethoprim–sulphamethoxazole or ceftriaxone followed by oral treatment for 1 year. Sodium valproate may be helpful for the involuntary movements which do not respond to antibiotics.
What is Myotonia?
Myotonia is a stiffness of muscles with inability to relax after voluntary contraction (action myotonia), or induced by electrical or mechanical (e.g. percussion
myotonia) excitation. The phenomenon is often described by patients as ‘cramp’
or stiffness. This is a reflection of primary muscle disease (i.e. myogenic; cf.
neuromyotonia, neurogenic muscle stiffness, peripheral nerve hyperexcitability),
which persists after peripheral nerve or neuromuscular junction blockade.
Neurophysiology reveals myotonic discharges, with prolonged twitch relaxation phase, which may be provoked by movement, percussion, and electrical
stimulation of muscle; discharges typically wax and wane.
Myotonia may be aggravated by hyperkalaemia, depolarizing neuromuscular blocking drugs (e.g. suxamethonium), and anticholinesterase drugs
(neostigmine). Other factors that can induce myotonia include hypothermia,
mechanical or electrical stimulation (including surgical incision and electrocautery), shivering, and use of inhalational anaesthetics.
A similar clinical phenomenon of slow muscle relaxation may be observed
in other circumstances, for example hypothyroidism, but without the characteristic EMG findings of myotonia, hence this is labelled as pseudomyotonia.
Paramyotonia is myotonia exacerbated by cold and exertion (paradoxical myotonia).
Recognized causes of myotonia include
• myotonic dystrophy types 1 and 2;
• hyperkalaemic periodic paralysis;
• myotonia congenita (autosomal dominant Thomsen’s disease, autosomal
recessive Becker’s myotonia);
• K+-aggravated myotonia;
• Schwartz–Jampel syndrome (chondrodystrophic myotonia).
Mutations in genes encoding voltage-gated ion channels have been identified in some of the inherited myotonias, hence these are channelopathies: skeletal
muscle voltage-gated Na+ channel mutations have been found in K+-aggravated
myotonia, and also paramyotonia congenita and hyperkalaemic periodic paralysis. Chloride (Cl–) channel mutations have been identified in myotonia congenita.
These latter conditions respond best to mexiletine.
Woltman’s sign (also called Woltman’s sign of hypothyroidism or, in older references, myxedema reflex) is a delayed relaxation phase of an elicited deep tendon reflex, usually tested in the Achilles tendon of the patient. Woltman’s sign is named for Henry Woltman, an American neurologist.
What is Warm-up phenomenon?
The prolonged muscle contractions, which occur most commonly in the leg muscles in recessive mutations, and more commonly in the hands, face, and eyelids in dominant mutations, are often enhanced by inactivity, and in some forms are relieved by repetitive movement known as “the warm-up effect”. This effect often diminishes quickly with rest. Some individuals with myotonia congenita are prone to falling as a result of hasty movements or an inability to stabilize themselves after a loss of balance. During a fall, a person with myotonia congenita may experience partial or complete rigid paralysis that will quickly resolve once the event is over. However, a fall into cold water may render the person unable to move for the duration of submergence. As with myotonic goats, children are more prone to falling than adults, due to their impulsivity.
What are the characteristics of narcolepsy?
Signs and symptoms. There are two main characteristics of narcolepsy: excessive daytime sleepiness and abnormal REM sleep. The first, excessive daytime sleepiness (EDS), occurs even after adequate night time sleep.
What is glabellar reflex?
Glabellar reflex. The glabellar reflex is a primitive reflex. It is elicited by tapping the forehead between the eyebrows and nose and observing that the eyes blink. Successive tapping of the glabella eventually leads to habituation with blinking being suppressed.
What is nasopalpebral reflex?
It consists of bilateral contraction of the orbicularis oculi muscles when the bridge of the nose is percussed.
What are the different types of myoclonus?
The most common types of myoclonus include action, cortical reflex, essential, palatal, those seen in the progressive myoclonus epilepsies, reticular reflex, sleep and stimulus-sensitive.
What is cortical negative myoclonus?
Negative myoclonus: cortical negative myoclonus. There is a sudden interruption of the muscle activity when the patient is holding the left leg up against gravity. Duration of EMG silent period is 50–100 ms. Negative myoclonus (NM) is a motor phenomenon characterized by involuntary jerky movements due to a brief, sudden interruption of muscular activity. This motor disturbance can be observed in a variety of clinical conditions, that can range from physiological NM, occurring when falling asleep.
What is the difference between asterixis and tremor?
Asterixis is a tremor of the hand when the wrist is extended, sometimes said to resemble a bird flapping its wings. This motor disorder is characterized by an inability to maintain a position, which is demonstrated by jerking movements of the outstretched hands when bent upward at the wrist. The tremor is caused by abnormal function of the diencephalic motor centers in the brain, which regulate the muscles involved in maintaining position. Asterixis is associated with various encephalopathies du
What is Negativism?
Negativism is a motor sign of mental disorder, usually schizophrenia, consisting
of the patient doing the opposite of what is asked and actively resisting efforts
to persuade compliance. Movement of a limb in response to application of pressure despite the patient having been told to resist (mitgehen) is one element of
negativism. It may also be a feature of catatonia. The similarity of some of these
features to gegenhalten suggests the possibility of frontal lobe dysfunction as the
underlying cause.
What is gegenhalten?
Involuntary resistance to passive movement, that ↑ with velocity of movement and continues through the full arc of motion; gegenhalten may be due to diffuse forebrain dysfunction,
What is Neglect?
Neglect is a failure to orient towards, respond to, or report novel or meaningful stimuli. If failure to respond can be attributed to concurrent sensory or
motor deficits (e.g. hemiparesis, hemianopia, visuospatial deficits) neglect is not
present.
Neglect can involve stimuli in the extra personal environment (e.g. visual
neglect) or personal space (e.g. personal neglect or asomatognosia). This
dichotomy may also be characterized as egocentric (neglecting hemispace defined
by the midplane of the body) and allocentric (neglecting one side of individual
stimuli). Neglect of contralateral hemispace may also be called unilateral spatial neglect, hemi-inattention, or hemineglect. Lesser degrees of neglect may be
manifest as extinction (double simultaneous stimulation). Motor neglect may be
evident as hemiakinesia, hypokinesia, or motor impersistence. Alexia may sometimes be a consequence of neglect (neglect alexia). Alloaesthesia and Allokinesia may also be features of neglect.
Neglect may be obvious (e.g. patient not dressing one side of the body), but
is sometimes more subtle, in which case it may be tested for using various simple
tests:
Neglect is more common after right rather than left brain damage, usually of
vascular origin. The angular gyrus and parahippocampal gyrus may be central
to the development of visual neglect. Marked degrees of neglect may seriously
hamper attempts at neurorehabilitation.
What is Eastchester clapping sign?
It is a useful bedside test to demonstrate hemispatial neglect. The sign is named after curious students at Eastchester High School who inquired, “What happens if you ask patients with neglect to clap their hands?”
What is Extinction?
It is a neurological disorder that impairs the ability to perceive multiple stimuli of the same type simultaneously. Extinction is usually caused by damage resulting in lesions on one side of the brain. Those who are affected by extinction have a lack of awareness in the contralesional side of space (towards the left side space following a right lesion) and a loss of exploratory search and other actions normally directed toward that side.
What is Impersistence?
It is used with motor skill where motor impersistence is characterized by the inability to sustain a movement Patients with right-sided lesions had significantly more impersistence than did those with left-sided lesions. The most discriminating tests were eye-closure, mouth-opening, tongue-protrusion, and gaze to the left. Right central and frontal lesions seemed to be more responsible for motor impersistence than were posterior or left-sided lesions. Although motor impersistence is sometimes seen with diffuse cerebral disease, it is also a sign of right-hemisphere lesions;
What is Negro’s Sign?
Negro has two eponymous signs:
• Cogwheel (jerky) type of rigidity in basal ganglia disorders;
• In both peripheral and central facial paralyses, the eyeball deviates outwards
and elevates more than normal when the patient attempts to look up due to
overaction of the inferior oblique and superior rectus muscles, respectively.
What is Neologism?
A neologism is a non-word approximating to a real word, produced in spontaneous speech; it is thought to result from an inability to organize phonemes
appropriately in the process of speech production. Hence, this is a type of literal
or phonemic paraphasia encountered in aphasic syndromes, most usually those
resulting from left superior temporal lobe damage (Wernicke type). (The word
‘scientist’ is said to be a neologism coined in the nineteenth century by William
Whewell.)
What is Neri’s Test?
The test focuses in on five personality aspects: Mind, Energy, Nature, Tactics, and Identity. Together they comprise the sixteen personalities of the NERIS Type Explorer Test, which was inspired by the philosophies of Carl Gustav Jung and the mother-daughter duo of Katharine Cook Briggs and Isabel Briggs Meyers.
What is Nerve Thickening?
The characterization of a peripheral neuropathy should always include examination to see if any nerves are thickened. Good places to feel for nerve thickening
include the elbow (ulnar nerve), anatomical snuffbox (superficial radial nerves),
and head of the fibula (common peroneal nerve).
What are the causes of Nerve Thickening?
Nerve thickening may be noted
in a variety of conditions, in some by examination, in others using imaging
techniques:
• Leprosy
• Hereditary motor and sensory neuropathies (HMSN), especially types I, III,
and IV (Refsum’s disease)
• Hereditary neuropathy with liability to pressure palsies (HNLPP)/
tomaculous neuropathy
• Neurofibromatosis 1
• Sarcoidosis
• Chronic inflammatory demyelinating neuropathy/ophthalmoplegic migraine
• Nerve tumours (localized)
• Amyloidosis (familial amyloid polyneuropathy, primary systemic amyloidosis): rare
What is Neuromyotonia?
Neuromyotonia is neurogenic muscle stiffness (cf. myotonia, myogenic muscle stiffness) which reflects peripheral nerve hyperexcitability. Clinically this is
manifest as muscle cramps and stiffness, particularly during and after muscle
contraction, and as muscular activity at rest (myokymia, fasciculations). Tendon
areflexia and abnormal postures of hands and feet may also be observed. Sensory
features such as paraesthesias and central nervous system features (Morvan’s
syndrome) can occur. A syndrome of ocular neuromyotonia has been described
in which spasms of the extraocular muscles cause a transient heterophoria and
diplopia.
Physiologically neuromyotonia is characterized by continuous motor unit
and muscle fibre activity which is due to peripheral nerve hyperexcitability; it
is abolished by curare (cf. myotonia). Spontaneous firing of single motor units as
doublet, triplet, or multiplet discharges with high-intraburst frequency (40–300/s)
at irregular intervals is the hallmark finding.
Neuromyotonia may be associated with autoantibodies directed against
presynaptic voltage-gated K+ channels. Around 20% of patients have an
underlying small cell lung cancer or thymoma, suggesting a paraneoplastic aetiology in these patients. Neuromyotonia has also been associated with mutations
within the voltage-gated K+ ion channel gene.
Neuromyotonia usually improves with symptomatic treatments such as carbamazepine, phenytoin, lamotrigine, and sodium valproate, in combination if
necessary. Paraneoplastic neuromyotonia often improves and may remit after
treatment of the underlying tumour.
What is Neuronopathy?
Neuronopathies are disorders affecting neuronal cell bodies in the ventral (anterior) horns of the spinal cord or dorsal root ganglia, hence motor and sensory
neuronopathies, respectively. Sensory neuronopathies (ganglionopathy, polyganglionopathy) have a more limited differential diagnosis than neuropathies,
including
• Paraneoplasia: anti-Hu antibody syndrome (although a similar syndrome,
presumed paraneoplastic, may occur in the absence of these antibodies)
• Sjögren’s syndrome
• Associated with anti-GD1b ganglioside antibodies
• CIDP
• HIV
Anterior horn cell (motor neurone) disorders may be classified as motor
neuronopathies, including motor neurone disease (amyotrophic lateral sclerosis),
spinal muscular atrophies, and poliomyelitis.
What is Neuropathy?
Neuropathies are disorders of peripheral nerves. Various clinical patterns of
peripheral nerve involvement may be seen:
• Mononeuropathy: sensory and/or motor involvement in the distribution of a
single nerve.
• Mononeuropathy multiplex: simultaneous involvement of two or more
nerves, usually in different parts of the body; if due to inflammatory disease,
as is often the case, this may be described as mononeuritis multiplex.
• Polyneuropathy: a widespread process, predominantly affecting the distal
parts of nerves; may be predominantly sensory (‘glove and stocking’ sensory
loss) or motor, with or without concomitant autonomic involvement.
These clinical patterns may need to be differentiated in practice from disorders affecting the neuronal cell bodies in the ventral (anterior) horns of the spinal
cord or dorsal root ganglia (motor and sensory neuronopathies, respectively);
and disorders of the nerve roots (radiculopathy) and plexuses (plexopathy).
Clinical signs resulting from neuropathies are of lower motor neurone type
(wasting, weakness, reflex diminution, or loss).
The causes of neuropathy are many. Mononeuropathies often result
from local compression (entrapment neuropathy), trauma, or diabetes.
Mononeuropathy multiplex often reflects intrinsic inflammation (e.g. polyarteritis nodosa, Churg–Strauss syndrome, systemic lupus erythematosus, rheumatoid arthritis, Sjögren’s syndrome, cryoglobulinaemia, isolated PNS vasculitis).
Polyneuropathies may have genetic, infective, inflammatory, toxic, nutritional,
and endocrine aetiologies. Many neuropathies, particularly polyneuropathies in
the elderly, remain idiopathic or cryptogenic, despite intensive investigation.
What is Amyotrophy?
It is progressive wasting of muscle tissues. Muscle pain is also a symptom. It can occur in middle-aged males with type 2 diabetes. It also occurs with motor neuron disease.
What is Neuronopathy?
It is a form of polyneuropathy and occurs as a result of neuron degeneration. It is a subgroup of disorders of the peripheral nervous system and involves the destruction of specific neurons in this area.
What is Anomic aphasia?
It, (also known as dysnomia, nominal aphasia, and amnesic aphasia) is a mild, fluent type of aphasia where individuals have word retrieval failures and cannot express the words they want to say (particularly nouns and verbs). Anomia is a deficit of expressive language.
What is Nuchal Rigidity?
Nuchal rigidity is neck stiffness and is usually synonymous with meningism,
in which case other signs of meningeal irritation are usually present (Kernig’s
sign, Brudzinski’s neck sign). If these other signs are absent, then isolated
nuchal rigidity may suggest a foraminal pressure cone. It may also occur in
syndromes causing predominantly axial (as opposed to limb) rigidity (e.g. progressive supranuclear palsy). In intubated patients, there may be resistance to
passive neck movements.
What is Nuchocephalic Reflex?
In a standing subject, rapid turning of the shoulders to either left or right (eyes
closed to avoid fixation) is associated with bilateral contraction of the cervical
musculature so that the head is held in the original position. This nuchocephalic
reflex is present in infants and children up to the age of about 4 years. Beyond this
age the reflex is inhibited, such that the head is actively turned in the direction
of shoulder movement after a time lag of about half a second. If the reflex is
present in adults (i.e. disinhibited), it is claimed to be a ‘regressive’ (primitive)
sign, indicative of diffuse cerebral dysfunction.
What is Nyctalopia?
Nyctalopia, or night blindness, is an impairment of visual acuity specific to
scotopic vision, implying a loss or impairment of rod photoreceptor function.
Patients may spontaneously complain of a disparity between daytime and nocturnal vision, in which case acuity should be measured in different ambient
illumination. Nyctalopia may be a feature of:
• Retinitis pigmentosa
• Vitamin A deficiency
• Cancer-associated retinopathy: most commonly associated with small cell
lung cancer (antirecoverin antibodies may be detected), though gynaecological malignancy and melanoma have also been associated (with antibipolar retinal cell antibodies in the latter).
What is Hallpike (Nylen-Bárány) maneuver?
In the Nylen-Bárány test for positional nystagmus (also called the Hallpike maneuver), the patient’s head is first rotated 45 degrees to the right or left; the patient is then rapidly moved from the seated to the supine position, and the head is allowed to hang over the edge of the examining table by 45 degrees. The eyes are kept open and in midposition.
What is Hemeralopia?
It, is the inability to see clearly in bright light and is the exact opposite of nyctalopia (night blindness), the inability to see clearly in low light. Hemera was the Greek goddess of day, and Nyx was the goddess of night.
What is Nystagmus?
Nystagmus, or talantropia, is an involuntary to-and-fro oscillatory movement
of the eyeballs, of which there are many varieties. It is usually bilateral, but
occasionally may be unilateral, as in internuclear ophthalmoplegia (INO). The
pathophysiological underpinnings are diverse, but all involve brainstem nuclei
and tracts which control eye movements and gaze holding, especially the III, IV,
and VI cranial nerve nuclei, paramedian pontine reticular formation, vestibular
nuclei, medial longitudinal fasciculus, central tegmental tract, cerebellar connections to these structures, interstitial nucleus of Cajal, and nucleus prepositus
hypoglossi. The nature of the nystagmus may permit inferences about the precise location of pathology. Observations should be made in the nine cardinal
positions of gaze for direction, amplitude, and beat frequency of nystagmus.
Nystagmus may be abortive or sustained in duration.
Nystagmus may be classified in various ways:
• Physiological:
Optokinetic nystagmus (OKN; e.g. looking out of a moving railway
carriage)
Induced by vestibular stimuli (e.g. merry-go-round; caloric testing)
Nystagmoid jerks: in extremes of lateral or vertical gaze (end-point
nystagmus, a form of gaze-evoked nystagmus)
• Pathological:
Nystagmus may be classified according to direction, waveform,
anatomy/aetiology, or clinical frequency (common, rare)
It is important to distinguish nystagmus from other involuntary eye movements
such as square wave jerks, ocular flutter, and opsoclonus.
• Directional classification of nystagmus:
Horizontal (common)
Vertical (rare):
Downbeat: seen not only with structural lesions of the cervicomedullary junction, midline cerebellum, and floor of the fourth
ventricle, but also with more diffuse cerebellar disease
Upbeat: of less localizing value than downbeat; upbeat nystagmus
may occur with pontomesencephalic, pontomedullary, and even
caudal medullary lesions (infarct, inflammation); bow-tie nystagmus
is probably a variant of upbeat nystagmus
Torsional: usually accompanies horizontal nystagmus of peripheral
vestibular (labyrinthine) origin
• Waveform classification of nystagmus:
Jerk nystagmus:
At least one of the directions of eye movement is slow (slow phase;
<40◦/s) followed by a rapid, corrective, saccadic movement in the opposite direction (fast phase) for which direction the nystagmus is named. However, since it is the slow phase which is pathological, it is more eloquent concerning anatomical substrate. The intensity of jerk nystagmus may be classified by a scale of three degrees: 1st degree: present when looking in the direction of the fast phase; 2nd degree: present in the neutral position; 3rd degree: present when looking in the direction of the slow phase (i.e. present in all directions of gaze). Pendular or undulatory nystagmus: In which the movements of the eyes are more or less equal in amplitude and velocity (sinusoidal oscillations) about a central (null) point. This is often congenital, may be conjugate or disconjugate (sometimes monocular), but is not related to concurrent internuclear ophthalmoplegia or asymmetry of visual acuity. Acquired causes include multiple sclerosis and brainstem infarctions. • Anatomical/aetiological classification of nystagmus: Peripheral vestibular: unidirectional (directed to side opposite lesion), and more pronounced when looking in direction of the fast phase (i.e. 1st degree), usually with a rotatory component and associated with vertigo. Tends to fatigue, and usually transient (e.g. in Hallpike manoeuvre). Nystagmus of peripheral vestibular origin is typically reduced by fixation (hence these patients hold their heads still) and enhanced by removal of visual fixation (in the dark, with Frenzel’s lenses). Central vestibular: unidirectional or multidirectional, 1st, 2nd or 3rd degree; typically sustained and persistent. There may be other signs of central pathology (e.g. cerebellar signs, upper motor neurone signs). Not affected by removal of visual fixation. Cerebellar/brainstem: commonly gaze-evoked due to a failure of gaze-holding mechanisms. It may be unidirectional with a unilateral cerebellar lesion (e.g. vascular disease) in which case it typically occurs when the eyes are looking in the direction of the lesion (cf. peripheral vestibular nystagmus); multidirectional nystagmus of cerebellar origin may occur in multiple sclerosis, drug/toxin exposure, cerebellar degenerations. Congenital: usually horizontal, pendular-type nystagmus; worse with fixation, attention, and anxiety. It may appear with blindness of childhood onset or be acquired with neurological disease (multiple sclerosis, mitochondrial disease, Whipple’s disease, Pelizaeus–Merzbacher disease). Other forms of nystagmus include • Ataxic/dissociated: in abducting >> adducting eye, as in internuclear ophthalmoplegia and
pseudointernuclear ophthalmoplegia.
• Periodic alternating:
primary position nystagmus, almost always in the horizontal plane,
which stops and then reverses direction every minute or so; 4–5 min
observation may be required to see the whole cycle; localizing value
similar to downbeat nystagmus.
• Convergence–retraction (Körber–Salus–Elschnig syndrome):
adducting saccades (medial rectus contraction), occurring spontaneously or on attempted upgaze, often accompanied by retraction of
the eyes into the orbits, associated with mesencephalic lesions of the
pretectal region (e.g. pinealoma).
• See-saw:
a disconjugate cyclic movement of the eyes, comprising elevation
and intorsion of one eye while the other eye falls and extorts, followed by reversal of these movements; may be congenital (e.g. with
albinism, retinitis pigmentosa) or acquired (mesodiencephalic or lateral medullary lesions, e.g. brainstem stroke, head trauma, syringobulbia).
Many pathologies may cause nystagmus, the most common being demyelination, vascular disease, tumour, neurodegenerative disorders of cerebellum and/or
brainstem, metabolic causes (e.g. Wernicke–Korsakoff’s syndrome), paraneoplasia, drugs (alcohol, phenytoin, barbiturates, sedative-hypnotic drugs), toxins, and epilepsy.
Treatment of nystagmus is usually that of the underlying cause, where possible. Pendular nystagmus may respond to anticholinesterases, consistent with
it being a result of cholinergic dysfunction. Periodic alternating nystagmus
responds to baclofen, hence the importance of making this diagnosis. See-saw
nystagmus may respond to baclofen, clonazepam, or alcohol.
What does optokinetic nystagmus mean?
Optokinetic nystagmus (OKN) is nystagmus that occurs in response to a rotation movement.
What is Myorhythmia?
It is an irregular tremor of slow frequency, usually present during both rest and action; due to a lesion in midbrain, commonly in the area of the red nucleus.
What is internuclear ophthalmoplegia?
Internuclear ophthalmoplegia (INO) describes a clinical syndrome of impaired adduction in one eye with dissociated horizontal nystagmus of the other abducting eye, due to a lesion in the medial longitudinal fasciculus (MLF) ipsilateral to the eye unable to adduct. It is a common finding in multiple sclerosis, but has a number of other aetiologies.
What is pseudo abducens palsy”?
Internuclear ophthalmoplegia (INO) of abduction (also known as “Lutz posterior INO”, “reverse INO”, or “pseudo abducens palsy”) is a rare horizontal gaze palsy that can be either unilateral or bilateral. It is an exam finding where the patient exhibits ABduction restriction and contralateral ADduction nystagmus.
What is Spasmus nutans syndrome?
Spasmus nutans syndrome is a rare disorder, causing (in combination): a high frequency, low amplitude nystagmus of a disconjugate nature; irregular head nodding; an abnormal head posture. Spasmus nutans is an acquired form of nystagmus that occurs in children typically within the first 2 years of life. It presents as a clinical triad of 1) nystagmus 2) head bobbing 3) torticollis.
What are causes of Vertigo?
It can be a symptom of many conditions and vertigo-related diagnoses can be divided into those related to the peripheral nervous system and the central nervous system.
Benign Paroxysmal Positional Vertigo
Benign paroxysmal positional vertigo (BPPV) is believed to be caused by calcium debris within the inner ear. Typically, a person with BPPV will describe a brief spinning sensation when moving their head in certain ways (e.g., tilting the head back to look up at the sky). Nausea may also be present, but rarely vomiting
Vestibular Labyrinthitis
Vestibular labyrinthitis, also called vestibular neuronitis, is a viral or post viral inflammatory condition that affects the eighth cranial nerve—a.k.a. your vestibulocochlear nerve, which transmits sound and balance information from your ear to your brain. This condition causes sudden, severe vertigo along with nausea, vomiting, and unstable walking.
Ménière’s Disease
Ménière’s disease results from abnormal fluid build-up in the inner ear. It’s associated with episodes of severe vertigo that last for minutes to hours, in addition to one-sided tinnitus, hearing loss, and ear fullness. Nausea, vomiting, and imbalance also commonly occur during the vertigo episodes.4
Otitis Media
Otitis media (infection of the middle ear) may cause nonspecific dizziness in addition to ear pain and decreased hearing.
Rare Conditions
There are a few rare peripheral nervous system conditions that may cause vertigo as well, such as:5
Otosclerosis: A condition that results from abnormal bone growth within the middle ear, causing hearing loss and, sometimes, vertigo and tinnitus
Labyrinthine concussion: A condition that causes hearing loss and, in some cases, vertigo as a result of head trauma to the inner ear
Peri lymphatic fistula: A condition in which a fistula (an abnormal connection) develops in one or more membranes that separate the air-filled middle ear from the fluid-filled inner ear. Vertigo occurs as a result of middle-ear pressure changes that are transferred to the inner ear, often when a person strains or sneezes.
Ramsay Hunt syndrome: This syndrome results from an infection of the facial nerve with the herpes zoster virus. In addition to a painful red, blistering rash along the ear or within the ear canal, a person experiences one-sided facial weakness, ear pain, hearing loss, and vertigo.
ear problems linked to vertigo
Examples of diseases that affect your central nervous system and may cause vertigo include the following.
Vestibular Migraine
Vestibular migraine refers to vertigo that occurs as a result of a migraine, which is classically a one-sided, throbbing headache. In addition to vertigo and headache, other symptoms may occur with vestibular migraine, such as nausea and sensitivity to light and/or sound.
Stroke
A stroke, especially in the brainstem or cerebellum, may cause vertigo. Other symptoms are usually present as well. For example, a brainstem stroke may also cause double vision and slurred speech.
Vestibular Schwannoma
Vestibular schwannoma, also called acoustic neuroma, is a benign (non-cancerous) tumor that develops on the eighth cranial nerve. In addition to vertigo, tinnitus and hearing loss may occur.
Of note, because this type of tumor is slow growing, a person’s vertigo may be subtle, often described as a vague feeling of swaying, tilting, or imbalance.
Multiple Sclerosis
Multiple sclerosis is an autoimmune, neurological disease in which a person’s immune system misguidedly attacks the protective coating of nerve fibers (called myelin) within the brain and/or spinal cord. If myelin damage occurs within certain areas of the brainstem or cerebellum, vertigo may result.
Epileptic Vertigo
Epileptic vertigo refers to vertigo that occurs as a result of a seizure disorder.
Other Important Causes
It’s important to keep in mind that heart problems, such as abnormal heart rhythms or vasovagal presyncope, can cause vertigo.8
While vertigo related to heart problems is often reported as more of a lightheaded than spinning or dizzy sensation, the distinction can be subtle, which is why a doctor will often investigate a heart problem with any complaint of vertigo or dizziness.
Besides heart problems, other possible causes of vertigo include:
Medication side effects (e.g., aminoglycoside toxicity)
Psychiatric concern (e.g., depression or anxiety)
Orthostatic hypotension from a variety of causes (e.g., dehydration, anaemia, or pregnancy)
What is the definition of opsoclonus?
Opsoclonus refers to uncontrolled eye movement. Opsoclonus consists of rapid, involuntary, multivectorial (horizontal and vertical), unpredictable, conjugate fast eye movements without intersaccadic intervals.
What is ocular opsoclonus?
●Opsoclonus is a disorder of ocular motility characterized by spontaneous, arrhythmic, conjugate saccades occurring in all directions of gaze without a saccadic interval. ●Myoclonus is a clinical sign that is characterized by brief, shock-like, involuntary movements caused by muscular contractions or inhibitions.
What is oscillopsia and Paroxysmal oscillopsia?
Understanding Oscillopsia. Permanent oscillopsia occurs due to a misalignment in your eyes, while paroxysmal oscillopsia often results from an abnormality in your vestibular system, which controls your sense of balance. The main symptoms of oscillopsia are that objects in your visual field appear to jump, blur or shake when you move.
What are causes of oscillopsia?
Some of the most common conditions that experts have associated with oscillopsia include:
neurological conditions, such as seizures, multiple sclerosis, and superior oblique myokymia
brain or head injuries, especially bilateral vestibular cerebellar injuries
conditions, such as stroke, that affect the eye muscles or muscles around the eyes
conditions that affect or damage the inner ear, including Meniere’s disease
conditions that cause brain inflammation, such as tumors or meningitis
Some people are born with conditions that cause oscillopsia, but most people develop it later in life.
What causes Palatal myoclonus?
Palatal myoclonus is a rapid spasm of the palatal (roof of the mouth) muscles, which results in clicking or popping in the ear. The movements of the palate vary in rate between 40 and 200 beats per minute. Chronic clonus is often due to lesions of the central tegmental tract (which connects the red nucleus to the ipsilateral inferior olivary nucleus). Uniquely, the clicking noise does not subside when the patient sleeps.
When associated with eye movements, it is known as oculopalatal myoclonus. Palatal myoclonus is most often due to damage (lesions) on brain nerve pathways. Stroke is the most common cause. The problem most often develops about a year after the stroke occurs. Other conditions such as multiple sclerosis, trauma, or tumour may also lead to this problem.
Does Palatal myoclonus occur in acute stroke?
Palatal myoclonus does not appear in the acute stage of stroke, but develops several months later. Occasionally, rhythmic, jerky movements are also observed in the face, eyeballs, tongue, jaw, vocal cord or extremities (mostly hands); they may not be synchronous with palatal movements.
What is the path of pendular nystagmus?
Pendular nystagmus is a sinusoidal oscillation. The waveform of pendular nystagmus may occur in any direction; it can be torsional, horizontal, vertical, or a combination of these, resulting in circular, oblique, or elliptical trajectories.
What is bilateral nystagmus?
Nystagmus is an involuntary to-and-fro oscillation of the eyes. Nystagmus may be congenital or acquired, and the movements may affect both eyes (bilateral) or just one eye (unilateral). Bilateral nystagmus may be conjugate, which means that both eyes have identical movements, or dissociated, which implies separate movements.
What is Obscurations?
Visual obscurations are transient losses (‘greying out’) of vision lasting a few seconds, occurring in the context of raised intracranial pressure (ICP), and especially associated with activities known to elevate ICP, such as coughing, sneezing, bending down, straining at stool, and relieved by their cessation. These symptoms are thought to reflect critical compromise of optic nerve head perfusion and are invariably associated with the finding of papilloedema. Obscurations mandate urgent investigation and treatment to prevent permanent visual loss.
Transient visual obscurations may occasionally be due to optic disc drusen.
ain swelling can be caused by a number of injuries and conditions, including:
Papilledema or papilloedema is optic disc swelling that is caused by increased intracranial pressure due to any cause. The swelling is usually bilateral and can occur over a period of hours to weeks. Unilateral presentation is extremely rare. It’s causes are –
traumatic injury to your head
not having enough red blood cells or haemoglobin (anaemia)
CSF build-up in your brain (hydrocephalus)
brain bleeding (hemorrhage)
(encephalitis)
(meningitis)
(hypertension)
(abscess)
brain tumor
idiopathic intracranial hypertension
What is Obtundation?
Obtundation is a state of altered consciousness characterized by reduced alertness and a lessened interest in the environment, sometimes described as psychomotor retardation or torpor. An increased proportion of time is spent asleep
and the patient is drowsy when awake. Obtundation is a less severe impairment
of consciousness than stupor.
What is Ocular Apraxia?
Ocular apraxia (ocular motor apraxia) is a disorder of voluntary saccade initiation; reflexive saccades and spontaneous eye movements are preserved. Ocular
apraxia may be overcome by using dynamic head thrusting, with or without
blinking (to suppress vestibulo-ocular reflexes): the desired fixation point is
achieved through reflex contraversive tonic eye movements to the midposition
following the overshoot of the eyes caused by the head thrust.
The anatomical substrate of ocular apraxia is not certain. Ocular apraxia
may occur as a congenital syndrome (in the horizontal plane only: Cogan’s
syndrome), or may be acquired in ataxia telangiectasia (Louis–Bar syndrome),
Niemann–Pick disease (mainly vertical plane affected), and Gaucher’s disease
(horizontal plane only).
What is Ocular Bobbing?
Ocular bobbing refers to intermittent abnormal vertical eye movements, usually conjugate, consisting of a fast-downward movement followed by a slow
return to the initial horizontal eye position. The sign has no precise localizing
value, but is most commonly associated with intrinsic pontine lesions, e.g. infarct,
haemorrhage, tumour, central pontine myelinolysis. It has also been described in
encephalitis, Creutzfeldt–Jakob disease, and toxic encephalopathies. Its pathophysiology is uncertain but may involve mesencephalic and medullary burst
neurone centres. Variations on the theme include
• Inverse ocular bobbing: slow downward movement, fast return (also known
as fast upward ocular bobbing or ocular dipping);
• Reverse ocular bobbing: fast upward movement, slow return to midposition;
• Converse ocular bobbing: slow upward movement, fast down (also known as
slow upward ocular bobbing or reverse ocular dipping).
What is Ocular Dipping?
Ocular dipping, or inverse ocular bobbing, consists of a slow spontaneous downward eye movement with a fast return to the midposition. This may be observed
in anoxic coma or following prolonged status epilepticus and is thought to be a
marker of diffuse, rather than focal, brain damage. Reverse ocular dipping (slow
upward ocular bobbing) consists of a slow upward movement followed by a fast
return to the midposition.
What is Ocular Flutter?
Ocular flutter is an eye movement disorder characterized by involuntary bursts
of back-to-back horizontal saccades without an intersaccadic interval (cf. square
wave jerks). Ocular flutter may be accurately diagnosed with oculography. The
postulated mechanism of ocular flutter is loss of ‘pause’ neuronal inhibition of
‘burst’ neurone function in the paramedian pontine reticular formation (PPRF).
A case of ocular flutter with a circumscribed inflammatory pontine lesion involving the PPRF, in which clinical and neuroradiological improvement occurred
together, has been reported, supporting the argument that, at least in some cases,
PPRF lesions may be associated with ocular flutter.
What does ocular bobbing mean?
It is sudden conjugate downward deviation of the eyes with a slow return to the normal position; seen in some comatose patients who have bilateral hemisphere lesions. Ocular bobbing is a rare sign of rapid downward movement of both eyes, followed by a slow return of the eyes to the midline position. The offending lesion is usually in the pons, secondary to infarction or hemorrhage. Ocular bobbing portends an extremely poor prognosis for neurologic recovery.
What is Ocular Tilt Reaction?
The ocular tilt reaction is a postural synkinesis consisting of the triad of:
• ocular torsion;
• lateral head tilt to the same side;
• skew deviation with hypotropia ipsilateral to the direction of head/eye
torsion.
The ocular tilt reaction (OTR) is due to disordered function of one utricle
or its brainstem connections (vestibular nerve, vestibular nuclei, medial longitudinal fasciculus, interstitial nucleus of Cajal), hence a brainstem otolith-ocular
reflex. It has occasionally been reported with cerebellar lesions and may be under
inhibitory cerebellar control. OTR may be tonic, as in the lateral medullary
syndrome, or paroxysmal, as in multiple sclerosis.
What is Tullio phenomenon?
Tullio phenomenon, sound-induced vertigo, dizziness, nausea or eye movement (nystagmus) was first described in 1929 by the Italian biologist Prof. Pietro Tullio. (1881–1941) During his experiments on pigeons, Tullio discovered that by drilling tiny holes in the semicircular canals of his subjects, he could subsequently cause them balance problems when exposed to sound. The cause is usually a fistula in the middle or inner ear, allowing abnormal sound-synchronized pressure changes in the balance organs. Such an opening may be caused by a barotrauma (e.g. incurred when diving or flying), or may be a side effect of fenestration surgery, syphilis or Lyme disease. Patients with this disorder may also experience vertigo, imbalance and eye movement set off.
What is Oculocephalic Response?
Oculocephalic responses are most commonly elicited in unconscious patients; the
head is passively rotated in the horizontal or vertical plane (doll’s head manoeuvre) and the eye movements are observed. Conjugate eye movement in a direction
opposite to that in which the head is turned is indicative of an intact brainstem (intact vestibulo-ocular reflexes). With pontine lesions, the oculocephalic responses may be lost, after roving eye movements but before caloric responses disappear.
What is doll’s eye maneuver?
A test of the oculocephalic reflex to assess the integrity of the brainstem in neonates and comatose patients. During the evaluation the patient’s eyes are held open, and the head is quickly rotated from one side to the other. Both eyes should deviate to the side opposite the direction of head rotation.
What is Oculogyric Crisis?
Oculogyric crisis is an acute dystonia of the ocular muscles, usually causing
upward and lateral displacement of the eye. It is often accompanied by a disorder of attention (obsessive, persistent thoughts), with or without dystonic or
dyskinetic movements. It occurs particularly with symptomatic (secondary), as
opposed to idiopathic (primary), dystonias, for example, postencephalitic and
neuroleptic-induced dystonia, the latter now being the most common cause. This
is usually an acute effect but may on occasion be seen as a consequence of chronic
therapy (tardive oculogyric crisis). It has also been described with Wilson’s disease, neuroleptic malignant syndrome, and organophosphate poisoning. Lesions
within the lentiform nuclei have been recorded in cases with oculogyric crisis.
Treatment of acute neuroleptic-induced dystonia is either parenteral benzodiazepine or an anticholinergic agent such as procyclidine, benztropine, or trihexyphenidyl.
What is Oculomasticatory myorhythmia (OMM)?
It is a pathognomonic manifestation of Whipple’s disease (WD) of the central nervous system. It is characterized by smooth, continuous, slow (1-3 Hz), pendular, convergent-divergent nystagmus, concurrent contractions of the masticatory muscles, supranuclear vertical gaze palsy, and occasionally, rhythmic movements of the limbs. It differs from other forms of pendular nystagmus in that it is smooth and continuous.
What is Oculomotor (III) Nerve Palsy?
Oculomotor (III) nerve palsy produces
• Ptosis: weakness of levator palpebrae superioris (LPS), +/− Müller’s muscle;
• Mydriasis: impaired parasympathetic outflow to the pupil (‘internal ophthalmoplegia’); most obvious in a well-lit room (cf. Horner’s syndrome);
• Diplopia: weakness of medial rectus (MR), inferior rectus (IR), superior rectus (SR), and inferior oblique (IO) muscles causing the eye to point ‘down
and out’ (external ophthalmoplegia); the presence of intorsion confirms
integrity of superior oblique muscle/trochlear (IV) nerve function.
These changes may be complete or partial.
Pathological correlates of third nerve palsy may occur anywhere from the
brainstem to the orbit:
• Intramedullary (brainstem):
Nuclear: very rare; SR subnucleus lesion causes bilateral denervation;
other clinical signs may be expected, such as pupillary (Edinger–
Westphal nucleus) and medial longitudinal fasciculus involvement.
Fascicular (within substance of midbrain): all muscles or specific muscles involved, + other clinical signs expected, such as contralateral
ataxia (Claude’s syndrome), hemiparesis (Weber’s syndrome).
• Extramedullary:
Subarachnoid space: peripherally located pupillomotor fibres often
spared by ischaemic lesions, but not by space-occupying lesions (e.g.
aneurysm), however, the distinction is not absolute.
Cavernous sinus: III runs over trochlear nerve; other oculomotor nerves
+/− trigeminal nerve often affected.
Superior orbital fissure: superior division/ramus to SR, LPS; inferior
to MR, IR, IO; selective involvement (divisional palsy) may occur;
proptosis with space-occupying lesions.
Orbit: paresis of isolated muscle almost always from orbital lesion or
muscle disease.
What is Pupil sparing?
The term pupil-sparing should be reserved for situations in which there is normal pupillary function but complete loss of eyelid and ocular motor (somatic) functions of the third nerve. This is the typical finding of an ischemic cranial neuropathy, often associated with pain, which improves.
What is Divisional patterns of oculomotor nerve palsy?
It usually indicates a lesion involving the oculomotor nerve distal to anterior cavernous sinus where the nerve divides into the superior and inferior branches. Clinically, third cranial nerve palsy is one of the most common diabetes related cranial neuropathies; nevertheless, isolated divisional palsy is still a rarity.
What is Ophthalmo-paresis?
It refers to weakness (-paresis) or paralysis (-plegia) of one or more extraocular muscles which are responsible for eye movements. It is a physical finding in certain neurologic, ophthalmologic, and endocrine disease. Internal ophthalmoplegia means involvement limited to the pupillary sphincter and ciliary muscle.
To perform the test, a patient is asked to hold an object, usually a flat object such as a piece of paper, between the thumb and index finger (pinch grip). The examiner then attempts to pull the object out of the subject’s hands.
What is pinch sign’?
Froment’s sign is a special test of the wrist for palsy of the ulnar nerve, specifically, the action of adductor pollicis. Froment’s maneuver can also refer to the cogwheel effect from contralateral arm movements seen in Parkinson’s disease.
A normal individual will be able to maintain a hold on the object without difficulty. However, with ulnar nerve palsy, the patient will experience difficulty maintaining a hold and will compensate by flexing the flexor pollicis longus of the thumb to maintain grip pressure causing a pinching effect.
Clinically, this compensation manifests as flexion of the interphalangeal joint of the thumb (rather than adduction, as would occur with correct use of the adductor pollicis). The compensation of the affected hand results in a weak pinch grip with the tips of the thumb and index finger, therefore, with the thumb in obvious flexion.
If asked to make the “OK” sign, patients will make a triangle sign instead. This ‘pinch-test’ exposes the weakness of the flexor pollicis longus muscle and the flexor digitorum profundus I leading to weakness of the flexion of the distal phalanges of the thumb and index finger.
What is One-and-a-Half Syndrome?
The one-and-a-half syndrome consists of an ipsilateral horizontal gaze palsy
and an ipsilateral internuclear ophthalmoplegia, such that the only preserved
horizontal eye movement is abduction in one eye; vertical movements and convergence are spared. This results from a brainstem lesion which involves both the
abducens (VI) nerve nucleus or paramedian pontine reticular formation, causing
ipsilateral horizontal gaze palsy, and the adjacent medial longitudinal fasciculus,
causing internuclear ophthalmoplegia. In young patients this is most often due
to demyelination, in the elderly to brainstem ischaemia; brainstem arteriovenous
malformation or tumour may also be responsible. Myasthenia gravis may cause
a pseudo-one-and-a-half syndrome.
A vertical one-and-a-half syndrome has also been described, characterized
by vertical upgaze palsy and monocular paresis of downgaze, either ipsilateral or
contralateral to the lesion.
What is an internuclear ophthalmoplegia?
An internuclear ophthalmoplegia (INO) typically presents as a complete adduction deficit of the ipsilateral eye when trying to look contralaterally, with associated abduction nystagmus of the contralateral eye.
What are the Cause of internuclear ophthalmoplegia (Ino)?
Causes of internuclear ophthalmoplegia (INO) include: Multiple sclerosis — Vascular brainstem lesion — Pontine glioma — Inflammatory encephalitis affecting the brainstem (e.g. autoimmune, infective) Myasthenia gravis (unusual).
Conjugate gaze palsies are neurological disorders affecting the ability to move both eyes in the same direction. These palsies can affect gaze in a horizontal, upward, or downward direction. These entities overlap with ophthalmoparesis and ophthalmoplegia.
What is Onion Peel, Onion Skin?
These terms have been used to describe the pattern of facial sensory loss
with perioral sparing (Dejerine pattern), seen with intramedullary or cervicomedullary lesions and with tabes dorsalis. It reflects the somatotopic sensory
representation in the spinal nucleus of the trigeminal nerve: midline face (nose,
mouth) represented rostrally, lateral facial sensation represented caudally. The
pattern of sensory impairment has also been termed ‘balaclava helmet’.
What is Ophthalmoparesis, Ophthalmoplegia?
Ophthalmoparesis is a weakness or limitation, ophthalmoplegia a paralysis, of
eye movements. Causes may be central (CNS pathways), or peripheral (cranial
nerve nuclei, cranial nerves, neuromuscular junction, extraocular muscles). A
distinction is sometimes drawn between:
• External ophthalmoplegia:
weakness of the extraocular muscles of central, neuromuscular, or
myopathic origin:
Supranuclear: e.g. progressive supranuclear palsy, abetalipoproteinaemia;
Nuclear, internuclear: e.g. internuclear ophthalmoplegia (INO),
Möbius syndrome;
Cranial nerve palsy: III, IV, VI, or combinations thereof;
Neuromuscular junction: myasthenia gravis;
Extraocular muscles: e.g. oculopharyngeal muscular dystrophy
(OPMD), chronic progressive external ophthalmoplegia (CPEO),
thyroid ophthalmopathy.
The term ‘ophthalmoplegia plus’ has been used to denote the combination
of progressive external ophthalmoplegia with additional symptoms and signs,
indicative of brainstem, pyramidal, endocrine, cardiac, muscular, hypothalamic,
or auditory system involvement, as in mitochondrial disease.
• Internal ophthalmoplegia:
fixity of the pupil with loss of all pupillary reflexes (iridoplegia) and
ciliary apparatus.
Hence in an oculomotor (III) nerve palsy there may be both internal and
external ophthalmoplegia.
If structural disease and myasthenia gravis are excluded, then mitochondrial
disorder (CPEO) may be responsible for ophthalmoplegia, even if this is not
evident on quadriceps muscle biopsy.
What is Opisthotonos?
Opisthotonos is an abnormal posture consisting of arching of the back and
extension of the limbs such that the body may be supported just on the head
and ankles (arc de cercle). Opisthotonos may be seen in:
• Coma; decerebrate rigidity
• Basilar meningitis
• Hydrocephalus
• Structural lesions of the posterior fossa
• Cerebellar fits due to intermittent tonsillar herniation
• Acute drug-(neuroleptic-) induced dystonic reaction; or chronic feature of
tardive dystonia
• Tetanus
• Syncope (especially in children)
• Metabolic disorders: kernicterus, Gaucher’s disease (type II)
• Drug-induced: propofol
• Pseudo seizures
As in decerebrate rigidity, opisthotonos may reflect unopposed extensor tone
from the intact vestibular nuclei released from supratentorial control.
What is Emposthotonos?
A tetanic contraction of the flexor muscles, curving the back with concavity forward.
What is Oppenheim’s Sign?
Oppenheim’s sign is a variant method for eliciting the plantar response, by application of heavy pressure to the anterior surface of the tibia, for example, with the
thumb, and moving it down from the patella to the ankle. Extension of the hallux (upgoing plantar response, Babinski’s sign) is pathological. Like Chaddock’s
sign, Oppenheim’s sign always postdates the development of Babinski’s sign as a
reliable indicator of corticospinal pathway (upper motor neurone) pathology.
What is Useless Hand’?
Hermann Oppenheim described the ‘Useless Hand’ in 1911 as a classical but uncommon presentation of multiple sclerosis, in which a hand loses useful function due to proprioceptive loss, with relatively preserved motor function. Light touch perception may be subjectively altered or can be relatively intact. The lesion is (usually) a demyelinating plaque in the posterior columns of the cervical spinal.
What is Chaddock reflex?
The Chaddock reflex is a diagnostic reflex similar to the Babinski reflex. Chaddock’s sign is present when stroking of the lateral malleolus causes extension of the great toe, indicating damage to the corticospinal tract. It was identified by Charles Gilbert Chaddock in 1911
What is Opsoclonus?
Opsoclonus, or saccadomania, is an eye movement disorder characterized by involuntary bursts of polydirectional saccades (sometimes with a horizontal preference) without an intersaccadic interval (cf. square wave jerks). Like ocular flutter, opsoclonus may be accurately characterized with oculography.
Although some normal individuals can voluntarily induce opsoclonus, generally it reflects mesencephalic or cerebellar disease affecting the omnipause
cells which exert tonic inhibition of the burst neurones which generate saccades.
Recognized causes of opsoclonus include
• Paraneoplasia: in children with neuroblastoma (Kinsbourne’s syndrome); in
adults the opsoclonus–myoclonus syndrome (‘dancing eyes, dancing feet’) is
most commonly associated with small cell lung cancer but it may also occur
in association with breast cancer in which case onconeural antibodies (antiRi, or type 2 antineuronal nuclear antibodies [ANNA-2]) may be detected
in serum and CSF.
• Postinfectious: a monophasic disorder following respiratory or gastrointestinal infection.
• Intraparenchymal (especially mesencephalic) lesions, e.g. tumour, demyelination, neurosarcoidosis, metabolic/toxic encephalopathy.
Postinfectious opsoclonus generally remits spontaneously. Of the paraneoplastic disorders, opsoclonus associated with lung and breast tumours persists
and the patients decline from their underlying illness; neuroblastoma associated
opsoclonus may be steroid responsive. IVIg, clonazepam, and valproate have also
been used as symptomatic treatments.
What is Optic Aphasia?
Optic aphasia is a visual modality-specific naming disorder. It has sometimes
been grouped with associative visual agnosia, but these patients are not agnosic
since they can demonstrate recognition of visually presented stimuli by means
other than naming, e.g. gesture. Moreover, these patients are not handicapped
by their deficit in everyday life, whereas agnosic patients are often functionally
blind. Objects that are semantically related can be appropriately sorted, indicating intact semantics. This is not simply anomia, since the deficit is specific to
visual stimuli; objects presented in tactile modality, or by sound, or by spoken
definition, can be named. Naming errors are often semantic, and perseverations
(‘conduit d’approche’) are common. Perception is intact, evidenced by the ability
to draw accurately objects which cannot be named. Reading is poorly performed.
Optic aphasia is associated with unilateral lesions of the left occipital cortex
and subjacent white matter.
The neuropsychological explanation of optic aphasia is unclear. It may be a
mild type of associative visual agnosia, despite the differences.
What is Conduit d’approche?
Conduction aphasia, also called associative aphasia, is an uncommon form of difficulty in speaking (aphasia). It is caused by damage to the parietal lobe of the brain. An acquired language disorder, it is characterised by intact auditory comprehension, coherent (yet paraphasic) speech production, but poor speech repetition. Affected people are fully capable of understanding what they are hearing, but fail to encode phonological information for production.
What is Optic Ataxia?
Optic ataxia is impaired voluntary reaching for a visually presented target, with
misdirection and dysmetria. It may resemble cerebellar ataxia. Visual fixation is
possible but reaching under visual guidance is impaired. Tactile search with the
palm and fingers may be undertaken in searching for an object, using somatosensory cues to compensate for impaired access to visual information. Hence this
may be characterized as a modality-specific apraxia, wherein visual information cannot be used to guide goal-directed movements. The disorder is both retinotopic and somatotopic.
Optic ataxia occurs with lesions of the intraparietal sulcus and regions
medial and superior to it; the primary visual cortex is intact. It is one feature, along with psychic paralysis of gaze (‘sticky fixation’) and simultanagnosia
(visual disorientation), of Balint’s syndrome in which there is some evidence for
parieto-occipital (and possibly frontal) lobe dysfunction (disconnection).
What is baelint syndrome?
Bálint’s syndrome is an uncommon and incompletely understood triad of severe neuropsychological impairments: inability to perceive the visual field as a whole (simultanagnosia), difficulty in fixating the eyes (oculomotor apraxia), and inability to move the hand to a specific object by using vision (optic ataxia).
What is Optic Atrophy?
Optic atrophy is pallor of the optic nerve head as visualized by ophthalmoscopy.
The temporal disc may appear pale in a normal fundus, so that optic atrophy can
only be confidently diagnosed when there is also nasal pallor, although temporal
pallor may follow damage to the macular fibre bundle with central visual defects.
Optic atrophy may be the consequence of any optic neuropathy which causes
optic nerve damage leading to gliotic change of the optic nerve head. Although
most often seen with optic nerve pathology, it may be a consequence of pathology
in the retina, optic chiasm, or optic tract. ‘Hemianopic’ optic atrophy indicates
involvement of the optic tract or lateral geniculate body.
The appearance of optic atrophy is non-specific with respect to aetiology.
Recognized causes include
• Previous optic neuritis
• Chronic papilloedema
• Chronic optic nerve compression (see Foster Kennedy syndrome)
• Hereditary: autosomal dominant optic atrophy, autosomal recessive optic
atrophy, Leber’s hereditary optic neuropathy (LHON), other mitochondrial
disorders, Behr’s syndrome
• Macular dystrophies
• Deficiency: tobacco-alcohol amblyopia; vitamin B12 deficiency
• Drug-induced: e.g. ethambutol, isoniazid, chloroquine
• Glaucoma
What is Optokinetic Nystagmus (OKN), Optokinetic Response?
Optokinetic nystagmus (OKN) is familiar to anyone who has watched a railway
passenger observing passing telegraph poles from the window of a moving train:
OKN is an involuntary rhythmic eye movement induced by observing moving
stimuli. In clinical practice a striped drum serves to test both visual pursuit and
saccades. Rotation of the stripe to the left produces leftward pursuit, followed
by a compensatory saccade to the right, followed by pursuit to the left of the
next stripe, with another compensatory saccade, and so on. Hence, OKN is a
physiological nystagmus.
Parietal hemisphere lesions (vascular or neoplastic) typically impair OKN.
Testing for OKN may be useful in patients with suspected hysterical visual loss,
since OKN cannot occur unless visual function is present; the response is lost
in blindness. An internuclear ophthalmoplegia may be made more evident by
testing OKN.
What is orators hand?
The hand is held in an “orator’s hand” posture. This is typical of a high median nerve palsy, in which there is paralysis of the flexor pollicis longus and the flexor digitorum profundus of the second digit. This leads to an inability to pinch together the thumb and index finger.
What is Benedictine hand?
The hand of benediction, also known as benediction sign or preacher’s hand, occurs as a result of prolonged compression or injury of the median nerve at the forearm or elbow. The term “hand of benediction” refers to damage of the median nerve.
What is Oro-facial Dyspraxia?
Orofacial dyspraxia, or Buccofacial dyspraxia, is an inability to make voluntary, learned, movements with the oro-facial musculature, such as blowing out
a match, kissing, and licking the lips. Recognized causes of oro-facial dyspraxia
include
• a transient accompaniment of Broca’s aphasia, conduction aphasia, and
transcortical motor aphasia of cerebrovascular origin;
• trauma to pre-Rolandic area just above the Sylvian fissure;
• in some patients with primary non-fluent aphasia; a related but distinct condition of ‘progressive loss of speech output with orofacial dyspraxia’ has also
been described.
Clinical and imaging studies show a strong correlation between oro-facial
dyspraxia and lesions in the frontal operculum; it may also occur with subcortical
lesions involving periventricular and/or peristriatal white matter as well as the
basal ganglia.
What is Oromandibular Dystonia?
Oromandibular dystonia, including platysma, may occur spontaneously or
emerge with levodopa treatment in some patients with multiple system atrophy
(MSA-P type usually), resembling risus sardonicus.
What is Orthostatic Hypotension?
Orthostatic hypotension or postural hypotension is the finding of a persistent
drop in blood pressure (BP) on standing, defined as a fall in systolic BP below
20 mmHg and diastolic BP below 10 mmHg of baseline within 3 min of adopting the upright position. Normally there is a drop in blood pressure of lesser
magnitude on standing but this is usually quickly compensated for by the baroreceptor reflex. Measuring blood pressure automatically by passive head-up tilt
testing (tilt table) is also helpful in diagnosing orthostatic hypotension if the
active standing test is negative, and the history is suggestive, or in patients with
motor impairment.
Symptoms which may be associated with orthostatic hypotension include
exercise-induced or postprandial light-headedness, transient visual loss (usually
bilateral), blackouts (syncope), and pain in a ‘coathanger’ distribution across
the shoulders. There may be supine hypertension and reversal of the normal
circadian blood pressure rhythm (normally lower at night), with an increased
frequency of micturition at night. Other features of autonomic dysfunction may
be present, including dry eyes and dry mouth (xerophthalmia, xerostomia), a
tendency to constipation, and lack of penile erections.
Orthostatic hypotension may be found in:
• Pure autonomic failure (PAF)
• Neurodegenerative disorders such as multiple system atrophy, Parkinson’s
disease, dementia with Lewy bodies
• Phaeochromocytoma
• Other causes of autonomic neuropathy (e.g. Guillain–Barré syndrome,
amyloidosis)
However, the most common cause of orthostatic hypotension in hospital
practice is probably dehydration or overzealous treatment with antihypertensive
or diuretic agents.
What is treatment for Orthostatic Hypotension?
Management of orthostatic hypotension consists of education on factors that influence blood pressure. Non-pharmacological approaches include
increased salt and water intake, head-up bed tilt, and wearing elastic stockings
or a G-suit. Pharmacological therapies include fludrocortisone (first line), and
midodrine, ephedrine, or dihydroxyphenylserine (second line). Supine hypertension may also require treatment.
What is Xerophthalmia?
It is a progressive eye disease caused by vitamin A deficiency. Lack of vitamin A can dry out your tear ducts and eyes. Xerophthalmia can develop into night blindness or more serious damage to your cornea, the outer layer of your eye.
What is Oscillopsia?
Oscillopsia is an illusory movement of the environment due to excessive slip of
images on the retina (‘retinal slip’) during active or passive head movement,
producing a complaint of blurring, jumping, or oscillation of the visual representation of the environment. Oscillopsia is most often due to acquired bilateral loss of vestibular function (loss of the vestibulo-ocular reflexes). This may be tested for clinically by: recording visual acuity whilst the head is passively shaken horizontally, a drop of three to seven lines of acuity versus performance with the head still suggesting loss of VOR (the dynamic illegible E test); and by observing the optic disc with an ophthalmoscope as the head is gently shaken, the disc moving with the head if VOR are lost. Vestibular testing will also demonstrate bilateral loss of vestibular function.
Recognized causes of oscillopsia include
• acquired nystagmus, e.g. pendular nystagmus;
• superior oblique myokymia;
• other ocular oscillations.
Oscillopsia does not occur in congenital nystagmus, nor in opsoclonus,
presumably due to the operation of the visual suppression mechanism which
normally operates during saccadic eye movements.
Oscillopsia may be treated with clonazepam.
What is Oscillucusis?
Oscillucusis is an abnormal perception of an oscillation in the intensity of
ambient sounds, which may occur during a migraine attack.
What is Osmophobia?
Osmophobia, an aversion to smells, may form part of a migraine attack, along
with photophobia and phonophobia.
What is Palatal Tremor?
Palatal tremor, also known as palatal myoclonus, is characterized by rhythmic,
unilateral or bilateral, palatal contractions which continue during sleep; this may
be classified as a focal myoclonic syndrome. A distinction may be made between
essential and symptomatic palatal tremor, also known as primary and secondary
isolated palatal tremor.
Palatal tremor may be asymptomatic or there may be a clicking sound in
the inner ear, especially in essential palatal tremor. There may be associated
contractions of external ocular muscles (oculopalatal myoclonus), larynx, neck,
diaphragm (respiratory myoclonus, diaphragmatic flutter, or Leeuwenhoek’s disease), trunk, and limbs, which may bring the palatal tremor to attention. Palatal
tremor may be accompanied by pendular nystagmus and oscillopsia.
Palatal myoclonus is associated with lesions interrupting pathways between
the red nucleus, inferior olivary nucleus, and dentate nucleus (Guillain–Mollaret
triangle). Hypertrophy of the inferior olivary nucleus may be evident neuroradiologically (structural or functional imaging) and pathologically. This is a
consequence of a lesion in the dentato-olivary pathway which leads to transsynaptic degeneration and hypermetabolism of the olivary nucleus. Although many
cases are essential/idiopathic, recognized symptomatic causes of palatal tremor
include vascular lesions, trauma, neoplasia, demyelination, epilepsy, and, rarely,
adult-onset Alexander’s disease.
Drug treatment of palatal tremor is often unsuccessful, although reports
of benefit with 5-hydroxytryptophan, carbamazepine, sodium valproate, clonazepam, baclofen, and even sumatriptan have appeared. Botulinum toxin injections may also help.
What is “Eight-and-a-half” syndrome?
It is “one-and-a-half” syndrome (conjugated horizontal gaze palsy and internuclear ophthalmoplegia) plus ipsilateral fascicular cranial nerve seventh palsy.
A 52-year-old man with hypertension and diabetes mellitus presented with sudden onset of binocular diplopia on looking to the left side, right facial weakness, and epiphora in the right eye. Ocular motor examination revealed combination of right gaze paresis and right internuclear ophthalmoplegia suggestive of horizontal one‐and‐a‐half syndrome. Vertical ocular movements from the primary position were normal. In addition, he also had right lower motor neurone facial weakness.
What is Tinnitus?
It is the perception of noise or ringing in the ears. A common problem, tinnitus affects about 15 to 20 percent of people. Tinnitus isn’t a condition itself — it’s a symptom of an underlying condition, such as age-related hearing loss, ear injury or a circulatory system disorder. Although bothersome, tinnitus usually isn’t a sign of something serious. Although it can worsen with age, for many people, tinnitus can improve with treatment.
What is Palilalia?
Palilalia is a disorder of articulation characterized by the involuntary repetition
of syllables within a word, whole words, or phrases, hence a reiterative speech
disorder. The term stutter may be used for repetition of single syllables, and
the term palilogia has sometimes been used for the repetition of phrases, to
distinguish from palilalia. These phenomena may be encountered in:
• Parkinson’s disease (along with bradylalia, slowness of speech)
• Progressive supranuclear palsy
• Tourette syndrome (along with vocal and motor tics)
• Pick’s disease, as part of the so-called PES syndrome (palilalia, echolalia,
stereotypy) or the PEMA syndrome (palilalia, echolalia, mutism, amimia)
• Late stages of Alzheimer’s disease
• Postencephalitic parkinsonism (von Economo’s disease)
• Fahr’s disease (bilateral basal ganglia calcification)
• Thalamic/midbrain infarcts
• Normal finding in children below the age of about 6 years
In pathological states, palilalia may reflect difficulty in set shifting, as seen in
frontal lobe (frontal convexity) syndromes.
What is Palinacusis?
Palinacusis, or palinacousis, is the persistence of prior auditory perception.
Although sometimes classified as an illusory experience, musical hallucinations
may occur concurrently. The symptom may be related to seizures of temporal
lobe origin.
What is Palinopsia?
Palinopsia is an illusory visual phenomenon characterized by the persistence or
recurrence of visual images immediately after the stimulus has been removed,
hence visual perseveration. This is distinct from the physiological after-image. It
may be associated with polyopia. The description of the symptom may lead to it
being mistaken for diplopia (‘pseudodiplopia’).
Palinopsia occurs most frequently in the context of a left homonymous hemianopia, secondary to right occipitotemporal or occipitoparietal lesions: these may be vascular, neoplastic, metabolic, ictal, or drug- or toxin-induced (e.g. carbon monoxide poisoning). It has also been described with retinal and optic nerve disease and occasionally in normal individuals.
What is Hemianopsia?
It, or hemianopia, is a loss of vision or blindness (anopsia) in half the visual field, usually on one side of the vertical midline. The most common causes of this damage are stroke, brain tumor, and trauma.
What is Pallaesthesia?
Pallaesthesia is the appreciation of vibration sensation; its loss may be described
as pallanaethesia.
What is Palmaris Brevis Sign?
Palmaris brevis sign may be useful in localizing the site of an ulnar nerve lesion.
Innervated by the superficial ‘sensory’ division of the ulnar nerve in the wrist
(distal canal of Guyon), contraction of the palmaris brevis muscle may be evident with compressive lesions of the deep motor branch of the ulnar nerve which
cause intrinsic hand muscle weakness but no sensory loss (‘Ramsay Hunt syndrome’): ask the patient to ‘contract’ the hypothenar eminence with the fifth digit
forcibly abducted and look for skin corrugation. In sensory superficial division
ulnar nerve lesions, this sign is lost.
What is Palmomental Reflex?
The palmomental reflex consists of contraction of the mentalis muscle induced
by stroking the ipsilateral palm with a blunt object. It may indicate damage to
the contralateral paracentral cortex or its connections, but since it is observed in
about one quarter of normal adults and is very common in the normal elderly,
and may occur in other conditions, both its sensitivity and specificity are low. It
may be considered a frontal release sign or primitive reflex, but is less specific
than the grasp reflex. Induction of the reflex by stimulation of areas other than
the palm is more likely to be associated with cerebral damage.
What is Pandysautonomia?
Pandysautonomia is characterized by pre and postganglionic lesions of both the
sympathetic and parasympathetic pathways. This may be
• Congenital
• Acquired:
acute (e.g. after a viral infection such as infectious mononucleosis)
subacute (e.g. the ‘autonomic-only’ form of Guillain–Barré syndrome)
chronic (e.g. pure autonomic failure, multiple system atrophy, certain
hereditary neuropathies)
Clinical features include
• Visual blurring; pupillary areflexia
• Orthostatic hypotension
• Cardiac arrhythmia
• Abdominal pain, diarrhoea, vomiting, constipation, ileus, pseudo obstruction
Response to intravenous immunoglobulin has been reported in idiopathic Pandysautonomia.
What is Papilloedema?
Papilloedema is swelling (oedema) of the optic nerve head due to raised intracranial pressure (cf. other causes of disc swelling, which may cause Pseudopapilloedema). A number of stages of papilloedema are described: in the acute stage,
the only findings may be oedema at the superior and inferior poles of the disc,
absence of spontaneous venous pulsation, and enlargement of the blind spot. As
papilloedema progresses the whole disc is involved and splinter haemorrhages
may be evident at the disc margin. These early stages may be asymptomatic
or may be associated with transient losses of vision (obscurations), often provoked by activities or movements which further raise intracranial pressure, thus
compromising retinal perfusion pressure. Enlargement of the blind spot and constriction of the visual field may be evident, but visual acuity is often unimpaired
(cf. disc swelling due to papillitis). Chronic papilloedema produces gliosis of the
optic nerve head and eventually optic atrophy (‘sequential optic atrophy’) with
nerve fibre damage and permanent visual field defects.
What is Retinal venous pulsation?
It is a curious phenomenon first noted by Coccius in 1853 (Coccius, 1853), shortly after the invention of the direct ophthalmoscope. This observation was surprising because elsewhere in the body, pulsation is more easily detected in the arteries.
What is Pseudopapilloedema?
It is defined as anomalous elevation of one or both optic discs without oedema of the retinal nerve fiber layer. Papilledema, on the other hand, is a swelling of the optic disc due to increased intracranial pressure. It is important to distinguish Pseudopapilloedema from true papilledema, which can be the first sign of disease process with the potential for vision loss, neurological impairment, or death.
What is Ballism?
It is a condition characterized by twisting, shaking, and jerking motions.
What is ballismus?
Hemiballism is characterized by involuntary flailing movements of the extremities on one side. If the abnormal movements are restricted to both lower limbs, it is called paraballismus; if they are generalized it is termed biballism. HCHB spans a spectrum of involuntary, continuous, nonpatterned movement involving one side of the body. Ballismus is an involuntary hyperkinesia often confined to one half of the body (hemiballismus), but it may involve a single extremity (monoballismus) or, exceptionally, both halves of the body (paraballismus or biballismus). Hemiballismus is characterized by the occurrence of sudden, paroxysmal, large-amplitude, flinging, throwing movements of the arm and leg contralateral to a lesion. Chorea, paraballismus, and restless legs syndrome are known to occur during pregnancy, attributable to high estrogen levels.
What is Paradoxical Breathing?
The normal movement of the diaphragm (i.e. down in inspiration, causing outward abdominal wall movement) may be reversed (paradoxical) in conditions
which cause diaphragm weakness (i.e. inward abdominal wall movement on
inspiration), e.g. Guillain–Barré syndrome, acid maltase deficiency, phrenic nerve
injury, hence paradoxical abdominal movement, abdominal paradox, paradoxical breathing, or paradoxical diaphragm movement. This may be detectable
clinically or by X-ray screening of the diaphragm. Vital capacity is lower when
lying compared to standing. Paradoxical diaphragm movement is a potentially
alarming sign since it may indicate incipient respiratory failure.
The term paradoxical breathing may also be used to describe thorax and
abdomen moving in different directions when breathing, as with increased upper
airway resistance.
What is Paradoxical Flexor Reflex?
In the setting of spread of muscle stretch reflexes to neighbouring muscle groups if opposing muscles are differentially affected such that the reflex of one is lost while the other is increased, striking the tendon of the muscle with the lost reflex could be enough stimulation to the opposing muscle group to trigger its reflex loop, giving rise to paradoxical movement of the tested joint.
What is Gordon s sign?
Gordon’s sign. Gordon’s sign is a clinical sign in which squeezing the calf muscle elicits an extensor plantar reflex. It is found in patients with pyramidal tract lesions, and is one of a number of Babinski-like responses. The sign is named after Alfred Gordon.
What are inverted reflex?
They are any reflexes in which the usual response is reversed or does not conform to the pattern characteristic of the particular reflex.
What is Paradoxic triceps reflex?
This consists of flexion instead of extension of the forearm following stimulation of the triceps tendon. This response appears when the arc of the triceps reflex is damaged
What is Paraesthesia?
Paraesthesia is an abnormal sensation, often described as a tingling sensation, or
likened to ‘pins and needles’ or electricity, pricking, or even crawling (formication), i.e. positive sensory symptoms. The sensation is not pleasant but nor is it
painful (cf. dysaesthesia). Some patients may describe this sensation as ‘numbness’ or ‘deadness’, in which case care needs to be taken to differentiate it from
anaesthesia (i.e. a negative phenomenon). Some authorities reserve the term for
spontaneous rather than evoked positive sensory phenomena, as a distinction
from dysaesthesia.
Paraesthesia is a feature of neuropathy and may occur in the distribution
of a compressed or entrapped nerve, perhaps reflecting the mechanosensitivity
of nerves in this situation (e.g. Phalen’s sign, Tinel’s sign). Paraesthesia is a more
reliable indicator of the diagnosis of neuropathy than pain. Paraesthesia may also
be provoked by hyperventilation (especially perioral, hands, and feet [acroparaesthesia]). Central lesions may also produce paraesthesia (e.g. Lhermitte’s sign).
What is Paragrammatism?
Paragrammatism is the substitution of morphological elements and function
words in the context of fluent speech (e.g. Wernicke’s aphasia), as differentiated
from agrammatism, the omission of function words and bound morphemes in
non-fluent speech (e.g. Broca’s aphasia).
What is the definition of dysaesthesia?
It is a common effect of spinal cord injury characterized by sensations of numbness, tingling, burning, or pain felt below the level of the lesion. It may also follow a dermatome distribution of a spinal nerve, as in the pain of shingles.
What is MS and dyesthesia?
A person may also experience changes in their sense of taste or their response to temperature, and they may have difficulty speaking and eating. Link with MS Dysesthesia is a symptom of nerve-damaging conditions, in particular, those that target the central nervous system or the spinal cord and brain, such as MS. Dyesthesia is a very common symptom of MS. MS is an autoimmune condition in which the body damages or destroys myelin, the layer of protective fatty tissue that allows electrical impulses to pass through.
What is Parakinesia, Parakinesis?
These terms have been used in different ways by different authors, to describe
• a volitional purposeful act designed to camouflage, mask, or draw attention
away from an involuntary movement, such as chorea;
• strange movements of presumed psychogenic origin. It should be remembered that many movements previously thought to conform to this definition
have subsequently been recognized to have an organic basis (e.g. klazomania).
The terms are now seldom used.
What is Klazomania?
It refers to compulsive shouting; it has features resembling the complex tics such as echolalia, palilalia and coprolalia seen in tic disorders, but has been seen in people with encephalitis lethargica, alcohol abuse and carbon monoxide poisoning. It was first reported by L. Benedek in 1925 in a patient with postencephalitic parkinsonism. Little is known about the condition, and few cases have been reported.
What is Paralogia?
It is a reasoning disorder characterized by expression of illogical or delusional thoughts.
What is paralexia?
It is inability to read, spell, and write words, despite the ability to see and recognize letters; a familial disorder with autosomal dominant inheritance that occurs more frequently in males.
What is the Ganser syndrome?
Ganser Syndrome is a form of mental disorder in which the affected individual acts in a conscious manner in such as a way that he or she is terrible sick or unwell to gain attention when in fact the individual is perfectly normal. Ganser syndrome is a rare dissociative disorder characterized by nonsensical or wrong answers to questions and other dissociative symptoms such as fugue, amnesia or conversion disorder, often with visual pseudo hallucinations and a decreased state of consciousness.
What is Paralysis?
Paralysis is a total loss of power to move a body part; equivalent to the suffix
-plegia. The use of the word has not been entirely consistent, for example, paralysis agitans originally used by James Parkinson to describe the disease which now
bears his name. The periodic paralyses are a group of conditions characterized
by episodic muscular weakness and stiffness (myotonia) associated with mutations in the skeletal muscle voltage-gated sodium and calcium ion channel genes (channelopathies).
What is Channelopathy?
Sodium channel, implicated in channelopathies including Brugada syndrome, Long QT syndrome, Dravet syndrome, Paramyotonia congenita
Specialty Medical genetics, Neuromuscular medicine, Cardiology
Symptoms Dependent on type. Include: Syncope, muscle weakness, seizures, breathlessness
Complications Dependent on type. Include: Sudden death
Causes Genetic variants
Channelopathies are diseases caused by disturbed function of ion channel subunits or the proteins that regulate them.[1][2] These diseases may be either congenital (often resulting from a mutation or mutations in the encoding genes) or acquired (often resulting from autoimmune attack on an ion channel).
There are many distinct dysfunctions known to be caused by ion channel mutations. The genes for the construction of ion channels are highly conserved amongst mammals and one condition, hyperkalemic periodic paralysis, was first identified in the descendants of Impressive, a registered Quarter Horse.
The channelopathies of human skeletal muscle include hyper- and hypokalemic (high and low potassium blood concentrations) periodic paralysis, myotonia congenita and paramyotonia congenita.
Channelopathies affecting synaptic function are a type of synaptopathy.
What are the Types of channelopathies?
The types in the following table are commonly accepted.
Alternating hemiplegia of childhood Na⁺/K⁺-ATPase
Bartter syndrome various by type
Brugada syndrome various, by type
Catecholaminergic polymorphic ventricular tachycardia (CPVT) Ryanodine receptor
Congenital hyperinsulinism Inward-rectifier potassium ion channel
Cystic fibrosis Chloride channel
Dravet Syndrome Voltage-gated sodium channel
Episodic Ataxia Voltage-gated potassium channel
Erythromelalgia Voltage-gated sodium channel
Generalized epilepsy with febrile seizures plus Voltage-gated sodium channel
Familial hemiplegic migraine various
Associated with one particular disabling form of Fibromyalgia Voltage-gated sodium channel
Hyperkalemic periodic paralysis Voltage-gated sodium channel
Hypokalemic periodic paralysis Voltage-gated sodium channel
Or voltage-dependent calcium channel (calciumopathy)
Lambert-Eaton myasthenic syndrome Voltage-gated calcium channel
Long QT syndrome
main type Romano-Ward syndrome
Malignant hyperthermia Ligand-gated calcium channel
Mucolipidosis type IV Non-selective cation channel
Myotonia congenita Voltage-dependent chloride channel
Neuromyelitis optica Aquaporin-4 water channel
Neuromyotonia Voltage-gated potassium channel
Nonsyndromic deafness various
Paramyotonia congenita
(a periodic paralysis)
Voltage-gated sodium channel
Polymicrogyria (Brain Malformation) Voltage-gated sodium channel, SCN3A
Retinitis pigmentosa (some forms)
Ligand-gated non-specific ion channels
Short QT syndrome various potassium channels suspected
Timothy syndrome Voltage-dependent calcium channel
Tinnitus Voltage-gated potassium channel of the KCNQ family
Seizure Voltage-dependent potassium channel
What is Paramnesia?
Paramnesia is recalling as memories things which have not in fact taken place,
hence a distortion of episodic or autobiographical memory. This may be neurological or psychiatric in origin. Relation of paramnesias as the truth occurs in confabulation.
What is Reduplicative paramnesia?
It is the delusional belief that a place or location has been duplicated, existing in two or more places simultaneously, or that it has been ‘relocated’ to another site. It is one of the delusional misidentification syndromes; although rare, it is most commonly associated with acquired brain injury, particularly simultaneous damage to the right cerebral hemisphere and to both frontal lobes.
What is Paramyotonia?
Paramyotonia is similar to myotonia in that muscle does not relax normally following contraction (voluntary, percussion), which may prompt a complaint of
muscle aching or stiffness, but differs in that repetitive muscle use (e.g. exercise) accentuates the problem, leading to an increased delay in muscle relaxation
(worsening stiffness). For example, repeated forced voluntary eyelid closure in a
patient with paramyotonia may, after several attempts, lead to a failure of voluntary eyelid opening, the eyes remaining closed for a minute or so. Paramyotonia
particularly affects the face and forearms. This type of muscle stiffness may
also be sensitive to temperature, being made worse by cooling which may also
provoke muscle weakness. Weakness may outlast exposure to cold by several
hours. Neurophysiological studies may assist in the diagnosis of paramyotonia.
During the delayed muscle relaxation, electrical activity is not prominent, and
after muscle cooling the resting muscle membrane potential may be reduced from
around the normal −80 to −40 mV, at which point muscle fibres are inexcitable
(contracture).
Paramyotonia congenita (Eulenburg’s disease) is a channelopathy with mutations affecting the α-subunit of the sodium channel (SCN4A). Mutations in
the same gene have been documented in hyperkalaemic periodic paralysis and
K+-aggravated myotonia.
Symptomatic treatment with membrane-stabilizing agents like mexiletine
and tocainide or with the carbonic anhydrase inhibitor acetazolamide might be
tried. Precautions are necessary during general anaesthesia because of the risk of
diaphragm myotonia.
What is Paraparesis?
Paraparesis is a weakness of the lower limbs, short of complete weakness (paraplegia). This may result from lesions anywhere from cerebral cortex (frontal,
parasagittal lesions) to peripheral nerves, producing either an upper motor neurone (spastic) or lower motor neurone (flaccid) picture. A spinal cord lesion
(myelopathy) is probably the most common cause. Paraparesis may be symmetrical or asymmetrical. Recognized causes of paraparesis include
• Upper motor neurone lesions:
Traumatic section of the cord;
Cord compression from intrinsic or extrinsic mass lesion, e.g. tumour,
metastasis, abscess, empyema, haematoma (epidural, subdural);
Inflammatory lesions: acute transverse myelitis of viral origin, multiple sclerosis, neuromyelitis optica (Devic’s syndrome), systemic lupus
erythematosus, Behçet’s disease, giant cell arteritis (rare);
Structural lesions: tethered cord syndrome, arteriovenous malformation;
Metabolic: hereditary spastic paraplegia (HSP), adrenoleucodystrophy
(X-ALD), subacute combined degeneration of the cord (usually mild).
• Lower motor neurone lesions:
Acute or chronic neuropathies (Guillain–Barré syndrome, chronic
inflammatory demyelinating polyradiculoneuropathy).
What is Paraphasia?
Paraphasias are a feature of aphasias (disorders of language), particularly (but
not exclusively) fluent aphasias resulting from posterior dominant temporal lobe
lesions (cf. anterior lesions which tend to produce non-fluent aphasias with
agrammatism). Paraphasias refer to a range of speech output errors, both phonological and lexical, including substitution, addition, duplication, omission, and
transposition of linguistic units, affecting letters within words, letters within
syllables, or words within sentences. Paraphasic errors may be categorized as:
• Phonemic or literal:
Errors involve individual phonemes; impaired phonology (i.e. sound
based) causing approximations to real words; non-words resulting from
phonemic paraphasia may be referred to as neologisms. Phonemic
paraphasias may be encountered in Broca’s aphasia and conduction
aphasia, when the patient may recognize them to be errors, and
Wernicke’s aphasia.
• Formal:
Target word is replaced by another word that is phonemically similar.
• Morphemic:
Errors involving word stems, suffixes, prefixes, inflections, and other
parts of words.
• Verbal:
Errors involving whole words. These may be further classified as:
Semantic or categoric: substitution of a different exemplar from the
same category (e.g. ‘orange’ for ‘apple’; paradigmatic) or of a thematically related word (e.g. ‘sit’ for ‘chair’; syntagmatic). Verbal
paraphasias showing both semantic and phonemic resemblance to
the target word are called mixed errors. These types may be observed
in patients with Wernicke’s aphasia, who often seem unaware of their
paraphasias due to a failure of self-monitoring of output.
What is Paraplegia?
Paraplegia is a total weakness (paralysis) of the lower limbs (cf. paraparesis).
This may result from lower motor neurone lesions involving multiple nerve roots
and/or peripheral nerves (e.g. paraparetic Guillain–Barré syndrome) producing
a flaccid, areflexic paraplegia; but more commonly it is due to upper motor
neurone lesions interrupting corticospinal pathways (corticospinal tract, vestibulospinal tract, reticulospinal tracts, and other extrapyramidal pathways), most
usually in the spinal cord. The latter may acutely produce a flaccid areflexic
picture (‘spinal shock’), but later this develops into an upper motor neurone
syndrome (hypertonia, clonus, hyperreflexia, loss of superficial reflexes [e.g.
abdominal, cremasteric reflexes] and Babinski’s sign) with possible lower motor
neurone signs at the level of the lesion; bladder involvement is common (urinary
retention). Because of the difficulty in distinguishing whether an acute paraplegia
is of LMN or UMN origin, imaging to exclude potentially reversible cord compression is mandatory. Recognized causes of paraplegia of upper motor neurone
origin includes
• traumatic section of the cord;
• cord compression;
• inflammatory lesions: acute transverse myelitis of viral origin, multiple
sclerosis, neuromyelitis optica (Devic’s syndrome);
• ischaemic lesions; anterior spinal artery syndrome, venous infarction of the
cord.
In paraplegia of upper motor neurone origin, enhanced flexion defence
reflexes (‘flexor spasms’) may occur, producing hip and knee flexion, ankle and
toe dorsiflexion. Eventually such flexor responses may become a fixed flexion
deformity with secondary contractures (‘paraplegia in flexion’). Prevention of
this situation may be possible by avoiding spasms, which are often provoked
by skin irritation or ulceration, bowel constipation, bladder infection, and poor
nutrition. Physiotherapy and pharmacotherapy with agents such as baclofen,
dantrolene, and tizanidine may be used; botulinum toxin injections may be helpful for focal spasticity. ‘Paraplegia in extension’, with extension at the hip and
knee, may be seen with incomplete or high spinal cord lesions.
What are Bladder retention causes?
The most common cause of urinary retention is benign prostatic hyperplasia. Other common causes include prostatitis, cystitis, urethritis, and vulvovaginitis; receiving medications in the anticholinergic and alpha-adrenergic agonist classes; and cortical, spinal, or peripheral nerve lesions.
What is Hypertonia?
It is caused by upper motor neuron lesions which may result from injury, disease, or conditions that involve damage to the central nervous system. The lack of or decrease in upper motor neuron function leads to loss of inhibition with resultant hyperactivity of lower motor neurons. Different patterns of muscle weakness or hyperactivity can occur based on the location of the lesion, causing a multitude of neurological symptoms, including spasticity, rigidity, or dystonia.
What is a cremasteric reflex?
cremasteric reflex contraction of the ipsilateral cremaster muscle, drawing the testis upward, when the upper inner aspect of the thigh is stroked longitudinally. deep reflex one elicited by a sharp tap on the appropriate tendon or muscle to induce brief stretch of the muscle.
What is an abdominal reflex?
It is a superficial neurological reflex stimulated by stroking of the abdomen around the umbilicus. It can be helpful in determining the level of a CNS lesion. Being a superficial reflex, it is polysynaptic.
What is Parapraxia, Parapraxis?
Although this term may be used in common parlance as synonymous with a
‘Freudian slip’, in neurological practice it has a different meaning, referring to
one of the cardinal symptoms of ideomotor apraxia: a combination of deficient action selection with errors of sequencing of actions and spatial orientation
errors. Parapraxic errors include
• Perseveration: repetition of movements;
• Substitution: of one movement for another;
• Surplus movements;
• Verbal overflow: explaining a movement rather than performing it;
• Omission: incomplete movements;
• Conduit d’approche: several attempts to perform the correct movement;
• Body part as object.
What is paratonia and gegenhalten?
Paratonia and gegenhalten – the involuntary resistance to passive movement – are terms used in the field of neurology to describe a form of hypertonia often associated with dementia. It is however also found to be present in children suffering from developmental delay where it may be accompanied by signs of dyspraxia and learning disabilities.
What is primitive reflex?
Paratonia as a retained primitive reflex or a frontal release sign. Primitive reflexes – including paratonia, palmomental, glabellar, snout, suck, grasp and the Babinski response – are adaptive, reflex activities that occur naturally in neonates and which should disappear as the brain develops and matures reaching its adult state.
What is Body part as an object (BPO)?
It is to mime gestures occurs when a mime artist or other individual substitutes a part of their body – usually arms, fingers, or hands – to be part of an object they are miming. Miming uses representational gestures, meaning they are used to convey a message to others without the use of speech.
What is Paresis?
Paresis denotes a weakness which is less than total paralysis (-plegia), which may
be of upper or lower motor neurone origin. Various prefixes denote the location
of such weakness, e.g. hemiparesis, monoparesis, ophthalmoparesis, paraparesis,
quadriparesis.
Since localized pain may inhibit voluntary muscular exertion, apparent
weakness in such circumstances may be labelled ‘algesic pseudoparesis’.
What is von Economo disease?
It is the basis for postencephalitic parkinsonism, suspected to be of viral origin. Synonym (s): Economo disease; encephalitis lethargica; polio encephalitis infectiva; sleeping sickness
What is Parinaud’s Syndrome?
Parinaud’s syndrome, also sometimes known as the dorsal midbrain syndrome, the periaqueductal grey matter syndrome, or the pretectal syndrome, consists of:
• Eye movements:
Paralysis of vertical gaze, especially upgaze: Bell’s phenomenon may be
spared
Loss of convergence; convergence spasm may cause slow abduction
(‘midbrain pseudo-sixth’)
Skew deviation
Convergence–retraction nystagmus (Körber–Salus–Elschnig syndrome); sometimes downbeat nystagmus
• Eyelids:
Lid retraction (Collier’s ‘tucked lid’ sign) or ptosis (ventral extension
of lesion)
• Pupils:
Mydriasis
This constellation of signs results from dorsal midbrain lesions, such as
pineal tumours, which affect the pretectum and posterior commissure and so
interfere with conjugate eye movements in the vertical plane. The key anatomical
substrates, damage to which causes the syndrome, are probably the interstitial nucleus of Cajal and the nucleus of the posterior commissure and their projections.
What is Parkinsonism?
Parkinsonism is a clinical syndrome characterized by the presence of some or all
of the following features; there is overlap with so-called akinetic-rigid syndromes
in which these features predominate:
• Akinesia, hypokinesia (sine qua non)
• Rigidity: consistent (leadpipe) or jerky (cogwheeling; Negro’s sign)
• Bradykinesia
• Tremor, usually at rest, of frequency 3.5–7.0 Hz, ‘pill rolling’ type; there may
sometimes be an additional action component to the tremor, and very occasionally there is exclusively an action tremor. ‘Re-emergent tremor’ is also
described
• Stooped posture: forward flexion of trunk, flexion of knees, elbows; ‘simian
posture’
• Impaired postural reflexes, with or without a history of falls; propulsion,
retropulsion
• Mask-like facies, poverty of spontaneous facial expression (hypomimia)
• Reduced blink rate (this may be a particular feature of progressive supranuclear palsy)
• Hypophonic, monotonic voice (hypokinetic dysarthria)
• Widened palpebral fissure (Stellwag’s sign)
• Hypometria
• Seborrhea
• Sialorrhoea
• Festinant (shuffling) gait
• Micrographia
• Dystonic postures, e.g. striatal toe
• Apraxia
• Akathisia
• Cognitive impairment (usually of frontal–subcortical type)
• Hallucinations: minor (anwesenheit; passage type), or formed, visual > auditory. Insight into the non-reality of these experiences may be retained, hence ‘pseudohallucinations’
• Autonomic dysfunction, especially orthostatic hypotension
Conventionally parkinsonism is viewed as a disorder of the extrapyramidal system producing ‘extrapyramidal signs’, although this term has limitations:
despite the fact that some of the cardinal features of parkinsonism (bradykinesia,
rigidity, postural instability, tremor) result from pathology in the basal ganglia,
particularly affecting dopaminergic pathways, other features may reflect cortical
involvement, at least in part (e.g. apraxia, micrographia).
The incidence of parkinsonism increases dramatically with age; it is also
associated with an increased risk of death, particularly in the presence of a gait
disturbance.
What is differential diagnosis of parkinsonism?
The differential diagnosis of parkinsonism is broad, and includes
• Idiopathic Parkinson’s disease
• Multiple system atrophy
• Progressive supranuclear palsy (Steele–Richardson–Olszewski syndrome)
• Corticobasal degeneration, cortical basal ganglionic degeneration
• Drug-induced parkinsonism (e.g. neuroleptics, MPTP)
• Toxin-induced parkinsonism (e.g. carbon monoxide, manganese)
• Wilson’s disease (hepatolenticular degeneration); non-Wilsonian hepatocerebral degeneration
• Dementia with Lewy bodies
• Neuroleptic malignant syndrome
• Normal pressure hydrocephalus
• ‘Arteriosclerotic parkinsonism’, resulting from multiple subcortical infarcts
• Huntington’s disease, especially juvenile onset (Westphal variant)
• Postencephalitic parkinsonism (encephalitis lethargica, von Economo’s disease)
• Dementia pugilistica, posttraumatic parkinsonism
• Systemic lupus erythematosus
• Sjögren’s syndrome
• Hypoparathyroidism
• Parkinsonism–dementia complex of Guam
Obsessive slowness also enters the differential diagnosis but typical parkinsonian features (akinesia, rigidity) are not present in this condition.
It is crucial not to miss the diagnosis of Wilson’s disease, although rare, since
in the early stages this disorder is reversible with copper chelation therapy; hence
copper and caeruloplasmin should be checked in all patients with young-onset
(under age 50) parkinsonism (and dystonia).
Response to levodopa therapy is only reliably seen in idiopathic Parkinson’s disease, although some patients with multiple system atrophy or progressive supranuclear palsy may benefit. The features particularly responsive in Parkinson’s disease are bradykinesia and rigidity; tremor is less reliably helped.
What are the symptoms of hypophonia?
Symptoms such as shuffling gait, loss of dexterity, festination, freezing of gait, hypophonia and loss of articulation, and falls because of loss of postural reflexes. Hypophonia is a symptom of PD, and at times it became difficult to hear participants and therefore direct the assessments across the Internet link.
What is a supranuclear gaze palsy?
It is an inability to look in a vertical direction as a result of cerebral impairment. There is a loss of the voluntary aspect of eye movements, but, as the brainstem is still intact, all the reflex conjugate eye movements are normal.
What does supranuclear palsy, progressive mean?
Progressive supranuclear palsy, also called Steele-Richardson-Olszewski syndrome, is an uncommon brain disorder that causes serious problems with walking, balance and eye movements. The disorder results from deterioration of cells in areas of your brain that control body movement and thinking.
What causes death in supranuclear palsy?
Problems swallowing, which can lead to choking or inhaling food or liquid into your airway (aspiration). Aspiration can develop into pneumonia, the most common cause of death in people with progressive supranuclear palsy.
What is Parosmia?
Parosmia is a false smell, i.e. the subjective sensation of a smell which does
not exist (i.e. an hallucination). Such smells are usually unpleasant (cacosmia),
may be associated with a disagreeable taste (cacogeusia), and may be difficult
for the patient to define. Causes include purulent nasal infections or sinusitis
and partial recovery following transection of olfactory nerve fibres after head
injury. Transient parosmia may presage epileptic seizures of temporal lobe cortical origin (olfactory aura), particularly involving the medial (uncal) region. The
symptom may also be common amongst the normal population.
What is Parry–Romberg Syndrome?
Hemifacial atrophy is thinning of subcutaneous tissues on one side of the face; it
may also involve muscle and bone (causing enophthalmos), and sometimes brain,
in which case neurological features (hemiparesis, hemianopia, focal epileptic
seizures, cognitive impairment) may also be present.
The clinical heterogeneity of hemifacial atrophy probably reflects pathogenetic heterogeneity. The syndrome may result from maldevelopment of autonomic innervation or vascular supply, or as an acquired feature following trauma, or a consequence of linear scleroderma (morphoea), in which case a coup de sabre may be seen.
What is En coup de sabre (ECDS)?
It is a rare subtype of linear scleroderma that is limited to the hemiface in a unilateral distribution. The lesonal skin first exhibits contraction and stiffness that lead to characteristic fibrotic plaques with associated linear alopecia. The pan sclerotic plaques are ivory in colour with hyperpigmented to violaceous borders extending as a paramedian band on the frontoparietal scalp.
What is enophthalmos, enophthalmus?
Enophthalmos is the posterior displacement of the eyeball within the orbit due to changes in the volume of the orbit (bone) relative to its contents (the eyeball and orbital fat), or loss of function of the orbitalis muscle. It should not be confused with its opposite, exophthalmos, which is the anterior displacement of the eye.
Is enophthalmos progressive?
Enophthalmos may be sudden and static, non-changing (as may occur with trauma) or progressive. Sudden appreciation of enophthalmos does not necessarily imply sudden development. Depending on the cause, enophthalmos may progress over any time frame, ranging from minutes to years.
What is dysmetria in the brain?
Hemispheric cerebellar syndromes cause dysmetria in the typical motor sense that many think of when hearing the term dysmetria. A common motor syndrome that causes dysmetria is cerebellar motor syndrome, which also marked by impairments in gait (also known as ataxia), disordered eye movements, tremor, difficulty swallowing and poor articulation. Dysmetria (English: wrong length) is a lack of coordination of movement typified by the undershoot or overshoot of intended position with the hand, arm, leg, or eye. It is a type of ataxia. It can also include an inability to judge distance or scale.
What is past-pointing?
A physical sign in disease of the CEREBELLUM in which, if the eyes are closed, a pointing finger overshoots its intended mark towards the side of the cerebellar damage.
What is Pathological Crying, Pathological Laughter?
Pathological laughter and pathological crying (PLC), or forced laughter and crying, also referred to as involuntary emotional expression disorder, have been
defined as reflecting an incongruence of mood (subjective feeling) and expression
or affect (‘objective’, observed), such that patients laugh involuntarily though
not happy, or cry though not sad. There may be a sense that the patient is struggling against these displays of emotion, in contrast to the situation in other forms
of emotional lability where there is said to be congruence of mood and affect,
although sudden fluctuations and exaggerated emotional expression are common
to both, suggesting a degree of overlap.
PLC are ascribed to a loss (release) of the normal inhibition of the motor
component of facial expression (i.e. cortical–subcortical disinhibition). PLC may
occur in the context of a pseudobulbar palsy (‘pseudobulbar affect’) but not
invariably so.
What are the causes of Pathological Crying, Pathological Laughter?
PLC have been reported in:
• Multiple sclerosis: crying > laughing; related to intellectual impairment
(more extensive brain involvement, but not brainstem);
• Alzheimer’s disease;
• Stroke: PLC may be the harbinger of brainstem stroke or a feature of
anterior choroidal artery territory infarctions; rarely a feature of TIAs;
• Motor neurone disease;
• Head injury;
• Gelastic epilepsy.
A Pathological Laughter and Crying Scale has been developed. Suggested
treatments for PLC include amitriptyline, levodopa, amantadine, and serotonin reuptake inhibitors such as fluoxetine and citalopram.
What is Peduncular Hallucinosis?
Peduncular hallucinosis is a rare syndrome characterized by hallucinations and
brainstem symptoms. Hallucinations are vivid and naturalistic. Brainstem findings include oculomotor disturbances, dysarthria, ataxia, and impaired arousal.
Episodic memory impairments also occur. Pathology may be in midbrain,
thalamus, and pons.
What is Peek Sign?
One of the eye signs of myasthenia gravis: on attempted forced eye closure, orbicularis oculi may fatigue such that the patient ‘peeks’ through the partially open
palpebral fissure.
What is Peliopsia, Pelopsia?
Peliopsia or pelopsia is a form of metamorphopsia characterized by the misperception of objects as closer to the observer than they really are (cf. porropsia, teliopsia).
What is Pelvic Thrusting?
Pelvic thrusting may be a feature of epileptic seizures of frontal lobe origin; occasionally it may occur in temporal lobe seizures. Pelvic thrusting also occurs in pseudo-seizures, particularly those of the ‘thrashing’ variety.
Choreiform disorders may involve the pelvic region causing thrusting or rocking movements.
What is Pendular Nystagmus?
Pendular or undulatory nystagmus is characterized by eye movements which are
more or less equal in amplitude and velocity (sinusoidal oscillations) about a
central (null) point. In acquired causes such as multiple sclerosis, this may produce oscillopsia and blurred vision. Treatment options include gabapentin and memantine.
What is Percussion Myotonia?
Percussion myotonia is the myotonic response of a muscle to a mechanical stimulus, e.g. when struck with a tendon hammer. For example, a blow to the thenar
eminence may produce involuntary and sustained flexion of the thumb. This
response, which may be seen in myotonic dystrophy, reflects the impaired muscle
relaxation which characterizes myotonia.
What is Periodic Alternating Nystagmus?
Periodic alternating nystagmus is a horizontal jerk nystagmus, which damps or
stops for a few seconds and then reverses direction. Eye movements may need to
be observed for up to 5 min to see the whole cycle. Periodic alternating nystagmus
may be congenital or acquired, if the latter then its localizing value is similar to
that of downbeat nystagmus (with which it may coexist), especially for lesions
at the cervico-medullary junction (e.g. Chiari malformation). Treatment of the
associated lesion may be undertaken, otherwise periodic alternating nystagmus
usually responds to baclofen, hence the importance of correctly identifying this
particular form of nystagmus.
What is Myotonia?
It is a symptom of a small handful of certain neuromuscular disorders characterized by delayed relaxation (prolonged contraction) of the skeletal muscles after voluntary contraction or electrical stimulation. Myotonia is the defining symptom of many chanelopathies such as myotonia congenita, paramyotonia congenita and myotonic dystrophy.
What is Periodic Respiration?
Periodic respiration is a cyclical waxing and waning of the depth and rate
of breathing (Cheyne–Stokes breathing or respiration), over about 2 min, the
crescendo–decrescendo sequence being separated by central apnoeas. A so-called
variant Cheyne–Stokes pattern has hypopnoeas rather than apnoeas.
Periodic respiration may be observed in unconscious patients with lesions
of the deep cerebral hemispheres, diencephalon, or upper pons, or with central
or tonsillar brain herniation; it has also been reported in multiple system atrophy. Prolonged circulatory time (congestive heart failure) and hypoxaemia (e.g.
at altitude) may also cause periodic respiration, but with a shorter cycle.
What is Perseveration?
Perseveration refers to any continuation or recurrence of activity without appropriate stimulus (cf. intrusions). Perseverations may be repeated motor behaviours (e.g. drawing, writing) or speech. These are viewed as a failure to inhibit a previous response pattern. Sensory perseveration is also described, e.g. palinopsia in the visual system. A number of varieties of perseveration have been described, associated with lesions in different areas of the brain:
• ‘Stuck-in-set’:
Inappropriate maintenance of a current category or framework;
thought to reflect a deficit in executive function; associated with frontal
lobe (especially frontal convexity) damage, which is associated with
an inert, apathetic pattern of behaviour, rather than the disinhibited
pattern associated with orbitofrontal damage.
• ‘Recurrent’:
Unintentional repetition of a previous response to a subsequent stimulus; thought to represent an abnormal post-facilitation of a memory
trace; associated with posterior left (dominant) hemisphere damage;
commonly seen in aphasics, Alzheimer’s disease; this overlaps with
‘intrusions’.
• ‘Continuous’:
Inappropriate prolongation or repetition of a current behaviour without interruption; thought to represent a deficit of motor output; associated with basal ganglia damage.
What is Recruitment?
Recruitment, or loudness recruitment, is the phenomenon of abnormally rapid
growth of loudness with increase in sound intensity, which is encountered
in patients with sensorineural (especially cochlear sensory) hearing loss. Thus
patients have difficulty with sounds of low-to-moderate intensity (‘Speak up,
doctor’) but intense sounds are uncomfortably loud (‘There’s no need to shout,
doctor!’). Speech discrimination is relatively unimpaired in conductive hearing
loss.
‘Recruitment’ may also be used to refer to pathological ‘spread’ of tendon
reflexes, implying broadening of their receptive field.
What is Recurrent Utterances?
The recurrent utterances of global aphasia, sometimes known as verbal stereotypies, stereotyped aphasia, or monophasia, are reiterated words or syllables
produced by patients with profound non-fluent aphasia (e.g. Broca’s original
case, Leborgne, who could only repeat ‘tan, tan, tan’, by which name he was
known). The poet Charles Baudelaire (1821–1867) may have been reduced to a
similar state following a stroke.
What is Red Ear Syndrome?
Irritation of the C3 nerve root may cause pain, burning, and redness of the pinna.
This may also occur with temporomandibular joint dysfunction and thalamic
lesions.
What is Reduplicative Paramnesia?
Reduplicative paramnesia is a delusion in which patients believe familiar places,
objects, individuals, or events to be duplicated. The syndrome is probably heterogeneous and bears some resemblance to the Capgras delusion as described by psychiatrists.
Reduplicative paramnesia is more commonly seen with right (nondominant) hemisphere damage; frontal, temporal, and limbic system damage
has been implicated. This may occur transiently as a consequence of cerebrovascular disease, following head trauma, or even after migraine attacks, or more persistently in the context of neurodegenerative disorders such as Alzheimer’s disease.
What is Paramnesia?
It is memory-based delusion or confabulation, or an inability to distinguish between real and fantasy memories.
What is Reflexes?
Reflex action – a sensory stimulus provoking an involuntary motor response –
is a useful way of assessing the integrity of neurological function, since disease
in the afferent (sensory) limb, synapse, or efferent (motor) limb of the reflex arc
may lead to dysfunction, as may changes in inputs from higher centres.
Different types of reflex may be distinguished. Muscle tendon reflexes
(myotactic reflexes) may be either tonic (in response to a static applied force:
‘stretch reflex’) or phasic (in response to a brief applied force, for example, a
blow from a tendon hammer to the muscle tendon). The latter are of particular
use in clinical work because of their localizing value (see Table). However, there
are no reflexes between T2 and T12, and thus for localization one is dependent
on sensory findings, or occasionally cutaneous (skin or superficial) reflexes, such
as the abdominal reflexes.
Reflex Root value
Jaw jerk Trigeminal (V) nerve
Supinator (brachioradialis, radial) C5, C6
Biceps C5, C6
Triceps C7
Finger flexion (digital) C8, T1
Abdominal T7–T12
Cremasteric L1, L2
Knee (Patellar) L3, L4
Hamstring L5, S1
Ankle (Achilles) (L5) S1 (S2)
Bulbocavernosus S2, S3, S4
Anal S4, S5
Tendon reflex responses are usually graded on a five-point scale:
–: absent (areflexia; as in lower motor neurone syndromes, such as
peripheral nerve or anterior horn cell disorders; or acute upper motor
neurone syndromes, e.g. ‘spinal shock’);
+/−: present only with reinforcement (Jendrassik’s manoeuvre); hyporeflexia;
+: normal;
++: brisk normal;
+++: pathologically brisk (hyperreflexia, as in upper motor neurone syndromes).
Relative Afferent Pupillary Defect (RAPD) R
Reflex ‘spread’, or ‘recruitment’, for example, a finger jerk when eliciting the supinator or biceps jerk, is suggestive of corticospinal pathway (upper
motor neurone) pathology, producing an enlarged receptive field for the reflex
response; concurrent disruption of the local reflex arc may result in inverted
reflexes.
Reflex responses may vary according to the degree of patient relaxation or
anxiety (precontraction). Moreover, there is interobserver variation in the assessment of tendon reflexes (as with all clinical signs): a biasing effect of prior
knowledge upon reflex assessment has been recorded.
There is also a class or ‘primitive’, ‘developmental’, or ‘psychomotor’ signs,
present in neonates but disappearing with maturity but which may re-emerge
with ageing or cerebral (especially frontal lobe) disease, hence sometimes known
as ‘frontal release signs’.
What is Lateral medullary syndrome?
Lateral medullary syndrome is a neurological disorder causing a range of symptoms due to ischemia in the lateral part of the medulla oblongata in the brainstem. The ischemia is a result of a blockage most commonly in the vertebral artery or the posterior inferior cerebellar artery. Lateral medullary syndrome is also called Wallenberg’s syndrome, posterior inferior cerebellar artery (PICA) syndrome and vertebral artery syndrome. This syndrome is characterized by sensory deficits that affect the trunk and extremities contralaterally (opposite to the lesion), and sensory deficits of the face and cranial nerves ipsilaterally (same side as the lesion). Specifically, a loss of pain and temperature sensation if the lateral spinothalamic tract is involved.
What is Medial medullary syndrome?
Medial medullary syndrome, also known as inferior alternating syndrome, hypoglossal alternating hemiplegia, lower alternating hemiplegia,[1] or Dejerine syndrome,[2] is a type of alternating hemiplegia characterized by a set of clinical features resulting from occlusion of the anterior spinal artery. This results in the infarction of medial part of the medulla oblongata. deviation of the tongue to the side of the infarct on attempted protrusion, caused by ipsilateral muscle weakness, limb weakness (or hemiplegia, depending on severity), on the contralateral side of the infarct medullary pyramid and hence to the corticospinal fibers of the pyramidal tract, a loss of discriminative touch, conscious proprioception, and vibration sense on the contralateral side of the infarct (body below head)
What is Wallenberg’s syndrome?
Wallenberg’s syndrome is a neurological condition caused by a stroke in the vertebral or posterior inferior cerebellar artery of the brain stem. Symptoms include difficulties with swallowing, hoarseness, dizziness, nausea and vomiting, rapid involuntary movements of the eyes (nystagmus), and problems with balance and gait coordination.
What causes a pica stroke?
PICA is the most common site of occlusion from propagating thrombus or embolism caused by injury to the third section of the vertebral artery, and Wallenberg’s syndrome is the most common stroke caused by chiropractic manipulation (Caplan, 1986).
What is an internuclear ophthalmoplegia?
An internuclear ophthalmoplegia (INO) typically presents as a complete adduction deficit of the ipsilateral eye when trying to look contralaterally, with associated abduction nystagmus of the contralateral eye.
What are causes of Cause of internuclear ophthalmoplegia (Ino)?
Causes of internuclear ophthalmoplegia (INO) include: Multiple sclerosis — Vascular brainstem lesion — Pontine glioma — Inflammatory encephalitis affecting the brainstem (e.g. autoimmune, infective) Myasthenia gravis (unusual).
What is nystagmus in internuclear ophthalmoplegia?
Internuclear ophthalmoplegia (INO) is a disorder of conjugate lateral gaze in which the affected eye shows impairment of adduction. When an attempt is made to gaze contralaterally (relative to the affected eye), the affected eye adducts minimally, if at all. The contralateral eye abducts, however with nystagmus.
What is the medical term meaning eye ophthalmoplegia?
Internuclear ophthalmoplegia (INO) The INO is named for the side of limited adduction. This patient presented with an acute onset of binocular horizontal diplopia that was most noticeable in right gaze and difficulty tracking objects as they move to the right. He has vascular risk factors.
What is Wall-Eyed?

1. having exotropia. 2. having large, staring eyes, as some fishes. 3. marked by excited or agitated staring of the eyes, as in fear or astonishment. 4. having a milky whitish eye, as from an opacity of the cornea.
   What is Warm-Up Phenomenon?
   Easing of muscle stiffness with repeated contraction, the warm-up phenomenon,
   is reported by many patients with myotonia congenita (Thomsen’s disease,
   Becker’s disease), in contrast to the situation in paramyotonia.
   What is Wartenberg’s Sign?
   In ulnar neuropathy, Wartenberg’s sign refers to the slightly greater abduction
   of the fifth digit on the affected side, due to paralysis of the adducting palmar interosseous muscle and unopposed action of the radial-innervated extensor muscles (digiti minimi, digitorum communis).
   What is a Froment sign?
   A maneuver used to determine ulnar nerve damage, whereby the person examined grasps a piece of paper between thumb and forefinger. The clinician attempts to pull the paper away. The test result is positive if the distal phalanx of the thumb flexes to hold the paper.
   What is Wartenberg’s Sign?
   It refers to the slightly greater abduction of the fifth digit, due to paralysis of the abducting palmar interosseous muscle and unopposed action of the radial innervated extensor muscles (digiti minimi, digitorum communis).
   What is Wartenberg’s Syndrome?
   This should not be confused with Wartenberg’s Syndrome which is described as the entrapment of the superficial branch of the radial nerve with only sensory manifestations and no motor deficits.
   What is corneomandibular reflex?
   A prominent unilateral left corneomandibular reflex was observed and the patient was conscious and responsive to the examiner. This reflex consists of contralateral jaw deviation produced by corneal stimulation and has mostly been described in patients in coma.
   What is Wartenberg’s Swing Test?
   Wartenberg’s swing test is used to assess limb and trunk rigidity (cf. pendulum
   test of Wartenberg, used to measure spasticity, q.v.). With the patient standing,
   the examiner holds the shoulders and gently shakes backwards and forwards, the
   two sides out of phase. Normally, the passive arm swing induced by this movement will be out of phase with the trunk movements, but in rigidity the limbs and
   trunk tend to move en bloc. Passive swinging of the wrist or elbow joint may also
   be performed to assess rigidity.
   What is rolex sign?
   This lack of mobility, when affecting the upper limbs, may impair the functioning of self-winding wristwatches, which depend upon a periodic movement of the arm to keep working properly.
   What is Wasting?
   Wasting refers to a thinning of the musculature, also known as atrophy or, if of
   neurogenic origin, amyotrophy. Wasting may be a consequence of disorders of:
   • muscle (myopathies, dystrophies);
   • peripheral nerve (more so in axonal than demyelinating peripheral neuropathies);
   • anterior horn cells (e.g. motor neurone disease).
   Wasting may occur in chronic upper motor neurone syndromes (e.g. chronic
   hemiplegia) but is not as evident as in lower motor neurone syndromes where
   wasting may appear sub acutely (over a few weeks).
   Wasting may also be seen in general medical disorders associated with a
   profound catabolic state, e.g. cancer cachexia, uncontrolled heart failure, liver
   cirrhosis, and renal failure.
   What is Weakness?
   Weakness is an objective loss of muscle strength. This is conveniently quantified
   or rated using the MRC grading system:
   • 5 = normal power;
   • 4 = active movement against gravity and resistance;
   • 3 = active movement against gravity;
   • 2 = active movement with gravity eliminated;
   • 1 = flicker or trace of contraction;
   • 0 = no contraction (paralysis).
   However, this is not a linear scale; grade 4 often becomes subdivided into
   4−, 4, and 4+ (or even 5−) according to the increasing degree of resistance
   which the examiner must apply to overcome activity. It is also important to
   assess what effort the patient is making to comply with the testing; ‘apparent
   weakness’ or ‘pseudoparesis’ may be shorthand for lack of patient effort. Sudden
   ‘giving way’ of muscle contraction may be an indicator of this. Non-uniform
   resistance may also be due to pain (algesic pseudoparesis). Testing records only
   the best-forced maximal contraction and should not develop into an unseemly
   trial of strength between patient and examiner. Accepting all these difficulties, it should be acknowledged that the grading of weakness, like all clinical
   observations, is subject to some degree of observer bias.
   The pattern of muscle weakness may suggest its anatomical origin. So-called
   pyramidal weakness (i.e. affecting upper limb extensors more than flexors and
   lower limb flexors more than extensors) suggests an upper motor neurone lesion
   (corticospinal pathways). However, there is no evidence that pure lesions of the
   pyramidal tracts produce this picture: pyramidotomy in the monkey results in
   a deficit in fine finger movements, but without weakness. Moreover, a similar
   pattern of weakness may be observed in lower motor neurone disorders such as
   Guillain–Barré syndrome. Coexistent wasting suggests that muscle weakness is of
   lower motor neurone origin, especially if acute, although wasting may occur in
   long-standing upper motor neurone lesions. Weakness with minimal or no muscle wasting may be non-organic, but may be seen in conditions such as multifocal
   motor neuropathy with conduction block.
   What is Weber’s Test?
   Weber’s test is one of the tuning fork tests, which may be used to confirm a conductive component in unilateral or asymmetric hearing loss. The vibrating tuning
   fork (512 Hz preferred) is put on the middle of the forehead and the patient asked
   in which ear it is heard; this depends entirely upon bone conduction (BC). Hence
   the sound localizes to the side of a conductive hearing loss (where bone conduction is greater than air conduction, BC > AC) and away from the side of a
   sensorineural hearing loss.
   What is a normal Weber test?
   The patient is asked to report in which ear the sound is heard louder. A normal weber test has a patient reporting the sound heard equally in both sides. In an affected patient, if the defective ear hears the Weber tuning fork louder, the finding indicates a conductive hearing loss in the defective ear.
   What is a positive Rinne test?
   Rinne test. A normal or positive Rinne test is when sound is still heard when the tuning fork is moved to air near the ear (air conduction or AC), indicating that AC is equal or greater than (bone conduction or BC). Therefore, AC > BC; which is how it is reported clinically for a normal or positive Rinne result.
   What is Wernicke’s Aphasia?
   Wernicke’s aphasia is the classical ‘receptive aphasia’, in distinction to the
   ‘expressive aphasia’ of Broca, although this classification is problematic since
   there are concurrent ‘expressive’ problems in Wernicke’s aphasia. Other terms
   sometimes used for Wernicke-type aphasia are sensory aphasia or posterior
   aphasia.
   Considering each of the features suggested for the clinical classification of
   aphasias (see Aphasia), Wernicke’s aphasia is characterized by:
   • Fluency: fluent speech with phonemic and semantic paraphasias and paragrammatism (inappropriate use of syntax); ‘empty speech’ with few verbs
   and nouns; prosody usually preserved; at worst, flowing speech (logorrhoea)
   devoid of semantic meaning (jargon aphasia, semantic aphasia); automatic
   speech is often better preserved than spontaneous, e.g. counting, days of
   week, overlearned phrases (‘I’m fine’);
   • Comprehension: impaired auditory comprehension (sine qua non; ‘word
   deafness’); impaired reading comprehension probably also required (not
   specifically discussed by Wernicke);
   • Repetition: impaired;
   • Naming: severely impaired (anomia) and not aided by cueing (cf. Broca’s
   aphasia);
   • Reading: usually impaired, with numerous paralexic errors and impaired
   reading comprehension (cf. pure word deafness);
   • Writing: similarly affected.
   There may be associated anxiety, with or without agitation and paranoia,
   and concurrent auditory agnosia. Because of a loss of self-monitoring of output, patients are often not aware of the impairment, and behavioural disturbance
   sometimes misdiagnosed as ‘acute confusional state’ and even referral or admission to psychiatric hospital may occur, particularly if there is no or minimal
   accompanying hemiparesis. The differential diagnosis of Wernicke’s aphasia
   includes delirium and schizophasia.
   The neuroanatomical substrate of Wernicke’s aphasia has been a subject of
   debate. Wernicke placed it in the posterior two-thirds of the superior temporal
   gyrus and planum temporale (Brodmann area 22), but more recent neuroradiological studies (structural and functional imaging) suggest that this area may be
   more associated with the generation of paraphasia, whereas more ventral areas of
   temporal lobe and angular gyrus (Brodmann areas 37, 39, and 40) may be associated with disturbance of comprehension. A correlation exists between the size
   of the lesion and the extent of the aphasia. A similar clinical picture may occur
   with infarcts of the head of the left caudate nucleus and left thalamic nuclei.
   What is Rocket sign’?
   The ‘Rocket sign’ is the manifestation of motor impulsivity in Progressive Supranuclear Palsy (PSP). Patients with PSP may suddenly jump to their feet from a sitting posture without assistance, a manifestation of disinhibition and failure of planning, only to topple backwards into the chair because of postural instability, axial rigidity and bradykinesia. This sudden forward movement followed by the backward fall is known as the ‘Rocket sign’.1 Though ‘Rocket sign’ describes mainly backward falls, patients can fall to other directions also.2 The combination of frontal lobe and extrapyramidal dysfunction makes this sign specific to a very limited set of diseases like PSP.
   What is Wheelchair Sign?
   The so-called wheelchair sign describes patients with parkinsonism who start to
   use a wheelchair for mobility early in the course of their disease, usually because
   of repeated falls. Early falls are a typical feature of progressive supranuclear
   palsy (Steele–Richardson–Olszewski syndrome), but not idiopathic Parkinson’s
   disease or other parkinsonian syndromes.
   What is Wing-Beating Tremor?
   Wing-beating tremor is absent at rest but develops when the arms are extended,
   hence this is a postural tremor. It is said to be typical of Wilson’s disease
   (hepatolenticular degeneration).
   What is Winging of the Scapula?
   Winging of the scapula, or scapula alata, is a failure to hold the medial border
   of the scapula against the rib cage when pushing forward with the hands. It is
   most easily observed by asking the patient to push or press against a wall or the
   examiner’s hand whilst observing the scapula which lifts away from the posterior
   chest wall.
   Winging of the scapula may be a consequence of weakness of the serratus
   anterior muscle, usually due to a neuropathy of the long thoracic nerve of Bell,
   but sometimes as a consequence of brachial plexus injury or cervical root (C7)
   injury. It may also be of myopathic origin, as in facioscapulohumeral dystrophy.
   Weakness of trapezius, particularly the middle trapezius muscle, may also
   cause winging of the upper part of the scapula, more prominent on abduction of
   the arm, when the superior angle of the scapula moves farther from the midline.
   Hence spinal accessory (XI) nerve palsy enters the differential diagnosis.
   What is Witzelsucht?
   Witzelsucht, or the joking malady, refers to excessive and inappropriate facetiousness or jocularity, a term coined in the 1890s for one of the personality changes observed following frontal (especially orbitofrontal) lobe injury. This phenomenon may overlap with those described as moria or emotional lability.
   What is Emotional lability?
   Emotional lability is a neurological condition that causes uncontrollable laughing or crying, often at inappropriate times. It tends to affect people with pre-existing neurological conditions or injuries.
   What are causes of Emotional lability?
   Emotional lability after a stroke
   (Emotional lability often occurs after a stroke. According to the National Stroke Association, more than half of stroke survivors have symptoms of emotional lability.)
   Alzheimer’s disease
   dementia
   multiple sclerosis (MS)
   ALS (Lou Gehrig’s disease)
   Types of TBIs that can cause emotional lability include:
   blunt force head trauma
   skull fracture
   coup-countercoup injury
   contusion
   hematoma
   laceration
   penetrating injury
   infection
   brain swelling
   oxygen deprivation
   What are the early signs of frontotemporal dementia?
   Early signs of frontotemporal dementia may involve the following symptoms:
   Apathy or an unwillingness to talk.
   Change in personality and mood, such as depression.
   Lack of inhibition or lack of social tact.
   Obsessive or repetitive behaviour, such as compulsively shaving or collecting items.
   Unusual verbal, physical or sexual behavior.
   What are the causes of frontal lobe syndrome?
   A frontal lobe syndrome can be caused by a range of conditions including head trauma, tumours, degenerative diseases, neurosurgery and cerebrovascular disease. Frontal lobe impairment can be detected by recognition of typical clinical signs, use of simple screening tests, and specialist neurological testing.
   What is Woltman’s Sign?
   Woltman’s sign denotes slow-relaxing, or ‘hung-up’, tendon reflexes. These are
   most commonly seen in the context of untreated hypothyroidism, but have also
   been recorded in other situations, including treatment with β-blockers, diabetes
   mellitus, and complete heart block. The phenomenon is sometimes labelled
   ‘pseudomyotonia’ because of its superficial resemblance to the slow muscle relaxation of myotonia, but electrophysiological testing does not show myotonic discharges.
   Chorea may result in apparently ‘hung-up’ reflexes, perhaps due to a
   choreiform jerk after muscle relaxation.
   The mechanisms underlying Woltman’s sign are uncertain: changes in basal
   metabolic rate and in muscle fibre types (selective loss of fast twitch fibres) have
   been suggested.
   What is myotonia?
   Myotonia is a symptom of a small handful of certain neuromuscular disorders characterized by delayed relaxation (prolonged contraction) of the skeletal muscles after voluntary contraction or electrical stimulation. Myotonia is the defining symptom of many chanelopathies such as myotonia congenita, paramyotonia congenita and myotonic dystrophy.
   What is Pseudomyotonia?
   It is difficulty relaxing muscles after contracting the muscle.
   What is Wrestler’s Sign?
   This name has been given to the excessive effort in irrelevant muscle groups
   accompanied by prominent non-verbal signs of effort such as grunting in patients
   with apparent (‘functional’) weakness. It may coexist with intermittent voluntary
   effort, collapsing weakness, cocontraction of agonist and antagonist muscles, and
   inconsistency in clinical examination (e.g. inability to lift leg from couch when
   recumbent, despite preserved ability to stand up and walk).
   What is Wrist Drop?
   Wrist drop describes a hand hanging in flexion due to weakness of wrist
   extension. This results from radial nerve palsy, either in the axilla or spiral
   groove of the humerus (‘Saturday night palsy’, although other nerves may also
   be compressed by hanging the arm over a chair, e.g. ulnar, median). Distal
   lesions affecting branches of the posterior interosseous branch of the radial
   nerve may produce more circumscribed deformity, such as weak extension of
   metacarpophalangeal joints (‘finger drop’, ‘thumb drop’).
   What is Writer’s Cramp?
   Writer’s cramp, also known as graphospasm, la crampe des écrivains, or
   scrivener’s palsy, is a focal dystonia involving the hand and/or arm muscles, causing abnormal posturing of the hand when writing; it is the most common of the
   task-specific dystonias (once known as ‘craft palsies’). When attempting to write,
   patients may find they are involuntarily gripping the pen harder, and there may
   also be involuntary movement at the wrist or in the arm. A tremor may also
   develop, not to be confused with primary writing tremor in which there is no
   dystonia. Handwriting becomes illegible. Attempts to use the contralateral hand
   may be made, but this too may become affected with time (‘mirror dystonia’).
   The problem may be exclusive to writing (simple writer’s cramp) but some people develop difficulties with other activities as well (e.g. shaving; dystonic writer’s
   cramp), reflecting a dystonia of the hand or arm. Muscle fatigue may make writing more legible. Familial forms may be associated with mutations in the epsilon
   sarcoglycan gene (DYT11). There may be an association between writer’s cramp
   and carpal tunnel syndrome.
   There is some neurophysiological evidence that the condition is due to abnormalities within the spinal cord segmental motor programmes and muscle spindle
   afferent input to them.
   Writer’s cramp may be amenable to local botulinum toxin injections into the
   hand or arm muscles responsible for the involuntary movement. Other strategies
   which may be used include writing with a different grip (e.g. whole hand grip),
   using a fat-bodied pen or using a word processor.
   What is Wrong-Way Eyes?
   Thalamic hemorrhage (and rarely large lobar hemorrhage) can present with gaze deviation away from the side of the lesion, so-called “wrong-way eyes.” 1 Proposed mechanism explaining this observation include compression of the mesencephalon affecting crossed frontopontine fibers, irritative effects on the intralaminar thalamic nuclei, or an interhemispheric smooth pursuit imbalance.
   The Prévost sign, also known as the Vulpian sign, refers to conjugate ocular deviation in patients with acute cortical hemiparetic stroke. The direction is variable, depending on the location of the stroke 3. In a hemispheric stroke, the eyes usually deviate towards the lesion (away from the hemiparesis).
   What is Xanthopsia?
   Xanthopsia is a visual disturbance characterized by excessive perception of
   yellow colours (literally ‘yellow vision’). It may be associated with the use of various drugs including digoxin (especially if levels are toxic), thiazides (especially
   chlorothiazide), sulphonamides, and barbiturates. The mechanism is uncertain,
   but one possibility is that this is a partial form of achromatopsia, affecting one
   colour more than others. It has been suggested that the artist Vincent van Gogh
   (1853–1890) may have suffered from xanthopsia as a consequence of digitalis
   toxicity, accounting for the bright yellows in many of his later canvases.
   What is the definition of achromatopsia?
   Achromatopsia is a condition characterized by a partial or total absence of colour vision. People with complete achromatopsia cannot perceive any colours; they see only black, white, and shades of gray.
   What is Xerophthalmia, Xerostomia?
   Xerophthalmia, dryness of the eyes, and xerostomia, dryness of the mouth,
   due to impaired secretion from the lacrimal glands and the salivary glands,
   respectively, often occur together (sicca syndrome). This may reflect autonomic
   dysfunction, as for example, in Lambert Eaton myasthenic syndrome, or be due
   to autoimmune disorders such as Sjögren’s syndrome. Other causes of xerostomia include medications with anticholinergic properties, dehydration, diabetes,
   and radiotherapy for head and neck cancer.
   What is Yawning?
   Yawning is an arousal reflex thought to be generated in the brainstem reticular
   formation to counteract brain hypoxia; it may precede vasovagal syncope.
   Excessive or pathological yawning (chasm) is compulsive, repetitive yawning
   not triggered by physiological stimuli such as fatigue or boredom. Known
   associations of excessive yawning or salvos of yawning include
   • Presyncope
   • Hypoglycaemia
   • Drugs: SSRIs, imipramine, valproate, dopamine agonists
   • Migraine prodrome
   • Temporal lobe epileptic seizures
   • Encephalitis
   • Multiple sclerosis
   • Tumours of the fourth ventricle, frontal lobes
   • Electroconvulsive therapy
   • Postthalamotomy
   • Neuroleptic withdrawal
   • Parkinson’s disease, progressive supranuclear palsy, restless legs syndrome
   • Pseudobulbar palsy of motor neurone disease
   Although the mechanisms are uncertain, yawning may represent a disturbance of dopaminergic neurotransmission. Levodopa may help.
   What is Yips?
   Yips is the name given to a task-specific focal dystonia seen in golfers, especially
   associated with putting.
   What is Yo-Yo-Ing?
   Yo-yo-ing is a form of dyskinesia experienced by patients with idiopathic
   Parkinson’s disease who have been treated for several years with levodopa
   preparations, in which there are sudden and unpredictable swings between
   hypokinesia/akinesia (‘off’ state; freezing) and severe hyperkinesia (‘on’ state),
   sometimes known as the ‘on–off phenomenon’. Yo-yo-ing is difficult to treat:
   approaches include dose fractionation, improved drug absorption, or use of
   dopaminergic agonists with concurrent reduction in levodopa dosage.
   What is Zeitraffer Phenomenon?
   The zeitraffer phenomenon has sometimes been described as part of the aura
   of migraine, in which the speed of moving objects appears to increase, even the
   vehicle in which the patient is driving.
   What is Zooagnosia?
   The term zooagnosia has been used to describe a difficulty in recognizing animal faces. This may be observed as a component of prosopagnosia. In one case,
   this deficit seemed to persist despite improvement in human face recognition,
   suggesting the possibility of separate systems for animal and human face recognition; however, the evidence is not compelling. In a patient with developmental
   prosopagnosia seen by the author, there was no subjective awareness that animals
   such as dogs might have faces.
   What is Zoom Effect?
   The zoom effect is a metamorphopsia occurring as a migraine aura in which
   images increase and decrease in size sequentially.
   What is Jendrassik’s manoeuvre?
   The Jendrassik maneuver is a medical maneuver wherein the patient clenches the teeth, flexes both sets of fingers into a hook-like form, and interlocks those sets of fingers together. The tendon below the patient’s knee is then hit with a reflex hammer to elicit the patellar reflex.
   What is inverted reflex?
   It is any reflex in which the usual response is reversed or does not conform to the pattern characteristic of the particular reflex.
   What is inverted supinator sign?
   The Inverted Supinator sign is another pathological reflex that can be observed in the case of an upper motor neuron lesion. Rapid taps near the styloid process result in finger flexion or slight elbow extension
   What is Woltman’s sign?
   It, (also called Woltman’s sign of hypothyroidism or, in older references, myxedema reflex) is a delayed relaxation phase of an elicited deep tendon reflex, usually tested in the Achilles tendon of the patient. Woltman’s sign is named for Henry Woltman, an American neurologist. The delayed ankle jerks are associated with: hypothyroidism.
   What is Relative Afferent Pupillary Defect (RAPD)?
   An afferent pupillary defect (APD), or relative afferent pupillary defect (RAPD),
   is an abnormal pupillary response in which the normally equal direct and consensual pupillary reflexes are asymmetric, the direct response being less than the
   consensual. This may be particularly evident using the ‘swinging flashlight’ test,
   in which the two pupils are alternately illuminated every 2–3 s in a darkened
   room. Quickly moving the light to the diseased side may produce pupillary dilatation (Marcus Gunn pupil). Subjectively, patients may note that the light stimulus
   seems less bright in the affected eye.
   RAPD suggests an asymmetric optic nerve pathology, such as optic neuritis or tumour, causing a conduction defect; indeed, this is the most sensitive sign of optic nerve pathology. Although visual acuity may also be
   impaired in the affected eye, and the disc appears abnormal on fundoscopy,
   this is not necessarily the case. Since RAPD depends on asymmetry of
   optic nerve conduction, no defect may be observed if both optic nerves are
   affected.
   RAPD has also been described with lesions of the retina, optic chiasm, optic
   tract (contralateral), brachium of the superior colliculus, and pretectal nucleus
   (in the latter two situations without visual impairment).
   What is Retinal Venous Pulsation?
   Venous pulsation is evident in the normal retina when observed with an ophthalmoscope, particularly at the margin of the disc. It is sometimes difficult to see
   and may be more obvious in the recumbent position because of higher pressure
   within the retinal veins in that position.
   Venous pulsation is expected to be lost when intracranial pressure rises above
   venous pressure. This may be a sensitive marker of raised intracranial pressure
   and an early sign of impending papilloedema. However, venous pulsation may
   also be absent in Pseudopapilloedema and sometimes in normal individuals.
   Hence, the reliability of this sign has been questioned.
   What is Retinitis Pigmentosa?
   Retinitis pigmentosa, or tapetoretinal degeneration, is a generic name for inherited retinal degenerations characterized clinically by typical appearances on
   ophthalmoscopy, with peripheral pigmentation of ‘bone-spicule’ type, arteriolar
   attenuation, and eventually unmasking of choroidal vessels and optic atrophy.
   Despite the name, there is no inflammation; the pathogenetic mechanism may
   be apoptotic death of photoreceptors. This process may be asymptomatic in its
   early stages, but may later be a cause of nyctalopia (night blindness), and produce
   a midperipheral ring scotoma on visual field testing.
   A variety of genetic causes of isolated retinitis pigmentosa have been
   partially characterized:
   • autosomal recessive: linked to chromosome 1q;
   • X-linked: Xp11, Xp21;
   • autosomal dominant: 3q, 6p, 8.
   At least some of these are related to mutations in the gene for the rod cell
   protein rhodopsin.
   In most cases, patients with retinitis pigmentosa have no associated systemic
   or extraocular abnormalities, but there are a number of multisystem disorders in
   which it occurs,
   • Abetalipoproteinaemia (Bassen–Kornzweig syndrome; HARP syndrome);
   • Alström’s syndrome;
   • Cockayne syndrome;
   • Friedreich’s ataxia;
   • Lawrence–Moon–Bardet–Biedl syndrome;
   • Mitochondrial disorders (e.g. Kearns–Sayre syndrome and NARP);
   • Neuronal ceroid lipofuscinosis;
   • Peroxisomal disorders, Refsum’s disease;
   • Usher’s disease.
   What is Nyctalopia?
   It, also called night-blindness, is a condition making it difficult or impossible to see in relatively low light. It is a symptom of several eye diseases. Night blindness may exist from birth, or be caused by injury or malnutrition (for example, vitamin A deficiency)
   What is Retinopathy?
   Retinopathy is a pathological process affecting the retina, with changes observable on ophthalmoscopy; dilatation of the pupil aids observation of the peripheral retina. Common causes include
   • Diabetes mellitus: various abnormalities may occur, in both insulin dependent (IDDM) and non-insulin-dependent (NIDDM) patients.
   ‘Background’ diabetic retinopathy is manifest as microaneurysm, dot and
   blot haemorrhages, hard exudates, and diffuse retinal oedema, all of which
   may be asymptomatic. Oedema and hard exudates at the macula are common causes of visual impairment. Proliferative retinopathy is characterized
   by neovascularization of the disc due to retinal hypoxia, typically in IDDM,
   with the risk of vitreous haemorrhage, traction retinal detachment, and
   irreversible visual loss. Laser treatment of new vessels is the treatment of
   choice
   • Hypertension: hypertensive retinopathy may cause arteriolar constriction,
   with the development of cotton–wool spots; and abnormal vascular permeability causing flame-shaped haemorrhages, retinal oedema, and hard
   exudates; around the fovea, the latter may produce a macular star. Optic disc
   swelling may be seen in malignant hypertension. Arteriosclerosis, thickening
   of vessel walls with prolonged hypertension, may cause changes at arteriovenous crossings (‘AV nipping’). Systemic hypertension is associated with an
   increased risk of branch retinal vein and central retinal artery occlusion
   • Drug-induced, e.g. antimalarials (chloroquine); chlorpromazine
   • Retinitis pigmentosa
   • Serous retinopathy or chorioretinopathy: leakage of fluid into the subretinal
   space, causing unilateral sudden non-progressive visual loss
   • Cancer-associated retinopathy: arteriolar narrowing, optic atrophy
   • ‘Salt and pepper’ retinopathy of Kearns–Sayre syndrome (mitochondrial
   disorder)
   An electroretinogram (ERG) may be helpful in confirming the presence of a
   retinopathic disorder.
   What is Retrocollis?
   Retrocollis is an extended posture of the neck. Progressive supranuclear palsy
   (PSP; Steele–Richardson–Olszewski syndrome) is commonly associated with
   retrocollis (cf. antecollis in multiple system atrophy). Retrocollis may also be a
   feature of cervical dystonia (torticollis) and of kernicterus.
   What is Reverse Sensory Geste?
   Whereas the sensory geste antagoniste transiently reverses the severity of dystonia, reverse sensory geste worsens it, for example, in cervical dystonia
   (torticollis).
   What is Revilliod’s Sign?
   Revilliod’s sign is an acquired inability to wink. This is a sign, possibly early, of
   corticobulbar disease.
   What is Riddoch’s Phenomenon?
   Riddoch’s phenomenon is the dissociation of the perception of static and kinetic
   visual stimuli (statokinetic dissociation). This phenomenon does not have particular localizing value, since it may occur with both occipital and anterior visual
   pathway lesions.
   What is germanstmann syndrome?
   Gerstmann syndrome, a classic disorder, consists of four neuropsychologic disturbances: acalculia (impaired arithmetic skills), finger agnosia (inability to identify fingers), left/right confusion, and agraphia. Gerstmann–Sträussler–Scheinker syndrome (GSS) is an extremely rare, usually familial, fatal neurodegenerative disease that affects patients from 20 to 60 years in age. It is exclusively heritable, and is found in only a few families all over the world (according to NINDS).
   What is Right–Left Disorientation?
   Right–left disorientation is an inability to say whether a part of the body is on
   the right or left side or to use a named body part to command. This may occur
   in association with acalculia, agraphia, and finger agnosia, collectively known
   as the Gerstmann syndrome. Although all these features are dissociable, their
   concurrence indicates a posterior parietal dominant hemisphere lesion involving
   the angular and supramarginal gyri.
   What is Rigidity?
   Rigidity is an increased resistance to the passive movement of a joint which is
   constant throughout the range of joint displacement and not related to the speed
   of joint movement; resistance is present in both agonist and antagonist muscles. In these particulars, rigidity differs from spasticity. Rigidity also needs to
   be differentiated from stiffness. Rigidity may be described as:
   • consistent: ‘leadpipe rigidity’; or
   • jerky: ‘cogwheel rigidity’ or Negro’s sign, when a rhythmic fluctuation (i.e.
   tremor), like a ratchet or cogwheel, is superimposed on the background of
   sustained rigidity (NB cogwheeling, reflecting underlying tremor, may occur
   in the absence of rigidity, e.g. in essential tremor).
   The presence of rigidity may be made more obvious by reinforcing manoeuvres (e.g. clenching and relaxing the contralateral fist, performing mental arithmetic), a finding variously known as activated rigidity, or Froment’s sign, or
   synkinesis (but note that both Froment’s sign and synkinesis have other meanings
   too). However, this may occur in some normal subjects; it is most helpful in the
   diagnosis of Parkinson’s disease if unilateral. Rigidity may also be demonstrated
   using Wartenberg’s swing test.
   Rigidity is a feature of parkinsonism and may coexist with any of the
   other clinical features of extrapyramidal system disease, but particularly akinesia
   (akinetic-rigid syndrome); both are associated with loss of dopamine projections
   from the substantia nigra to the putamen. Rigidity is a feature of pathology
   within the basal ganglia.
   The pathophysiology of rigidity is thought to relate to overactivity of tonic
   stretch reflexes in the spinal cord due to excessive supraspinal drive to spinal cord
   α-motor neurones following loss of descending inhibition as a result of basal ganglia dysfunction. In other words, there is a change in the sensitivity of the spinal
   interneurones which control α-motor neurones due to defective supraspinal control. Hence rigidity is a positive or release symptom, reflecting the operation of
   intact suprasegmental centres. The physiological correlate of this is the increased
   EMG activity found in rigid muscles with increased 1A afferent fibre activity,
   suggesting maintained α–β linkage. In support of this, pyramidotomy has in the
   past been shown to produce some relief of rigidity.
   Rigidity in Parkinson’s disease may be lessened by treatment with levodopa
   preparations. The techniques of modern stereotactic neurosurgery may also
   be helpful, particularly stimulation of the subthalamic nucleus, although both
   thalamotomy and pallidotomy may also have an effect.
   The term rigidity may also be used to describe
   • posturing associated with coma: decorticate or decerebrate, flexor and
   extensor posturing, respectively;
   • a lack of mental flexibility, particularly evident in patients with frontal lobe
   dysfunction.
   What is swing test?
   For an adequate test, vision must not be entirely lost. In dim room light, the examiner notes the size of the pupils. The patient is asked to gaze into the distance, and the examiner swings the beam of a penlight back and forth from one pupil to the other, and observes the size of pupils and reaction in the eye that is lit.
   What is Wartenberg s migratory sensory neuropathy?
   Wartenberg’s migratory sensory neuropathy (also known as Wartenberg’s migrant sensory neuritis) (WMSN) is a rare form of neuropathy identified by Robert Wartenberg in 1958 which is easy to confuse with the early stages of multiple sclerosis or Guillain-Barré syndrome.
   What is Wartenberg’s Syndrome?
   It is described as the entrapment of the superficial branch of the radial nerve with only sensory manifestations and no motor deficits. In this condition, the patient reports pain over the distal radial forearm associated with Paresthesias over the dorsal radial hand.
   What is Hysterical blindness?
   It is a condition in which patients lose their ability to see. The term “hysterical blindness” has fallen out of favour in recent years, and this condition is now officially referred to as a conversion disorder.
   What causes cortical blindness?
   Acquired cortical blindness is most often caused by loss of blood flow to the occipital cortex from either unilateral or bilateral posterior cerebral artery blockage (ischemic stroke) and by cardiac surgery. In most cases, the complete loss of vision is not permanent and the patient may recover some of their vision (cortical visual impairment).
   What are the symptoms of acquired and transient cortical blindness?
   The most common symptoms of acquired and transient cortical blindness include: 1 A complete loss of visual sensation and of vision 2 Preservation/sparing of the abilities to perceive light and/or moving, but not static objects ( Riddoch syndrome) 3 A lack of visual fixation and tracking 4 Denial of visual loss ( Anton–Babinski syndrome) 5 Visual hallucinations 6 Macular sparing, in which vision in the fovea is spared from the blindness.
   What is Rinne’s Test?
   Rinne’s test is one of the tuning fork tests (512 Hz fork preferred), which is used
   to define whether there is a conductive element to hearing loss. The patient is
   asked to compare the loudness of a vibrating tuning fork held at the external
   auditory meatus (air conduction; AC) with the loudness of the fork held against
   the mastoid process (bone conduction; BC); masking of the other ear, for example, by rubbing the tragus, is advised. Normally air conduction is louder (AC >
   BC). If bone conduction sounds louder (BC > AC), then this is indicative of a
   conductive hearing loss. In sensorineural hearing loss, AC and BC are diminished
   to a similar extent, and air conduction remains louder (AC > BC).
   What is Weber hearing test?
   The Weber test is a quick screening test for hearing. It can detect unilateral (one-sided) conductive hearing loss (middle ear hearing loss) and unilateral sensorineural hearing loss (inner ear hearing loss). The test is named after Ernst Heinrich Weber (1795–1878). Conductive hearing ability is mediated by the middle ear composed of the ossicles: incus, malleus, stapes.
   What is the Schwabach’s test in hearing assessments?
   In Schwabach’s Test for hearing, the patient’s bone conduction is compared with that of the examiner (presuming that the examiner’s hearing is normal). In the Schwabach test the presence of a sensorineural impairment is indicated when the individual being tested cannot hear the bone-conducted sound as long as the examiner with normal hearing can. The individual with a conductive hearing loss, however, can hear the fork for a longer period…
   It is Beevor’s sign?
   It is medical sign seen in the selective weakness of the lower abdominal muscles, involving the movement of the navel towards the head on flexing the neck. Beevor’s sign is characteristic of spinal cord injury between T9 and T10 levels
   What is Risus Sardonicus?
   Risus sardonicus (‘sardonic smile’) due to spasm of the facial musculature is a classic feature of the neuromuscular syndrome of tetanus, now exceptionally rarely seen in the developed nations. Risus sardonicus may also occur in the context of dystonia, more usually symptomatic (secondary) than idiopathic (primary) dystonia.
   What are the symptoms of oromandibular dystonia?
   Individuals with oromandibular may first notice symptoms as a twitching or tightness in the jaw or face. Symptoms evolve over time and then typically stabilize. Symptoms are typically worsened by stress and may improve after sleep (though symptoms of acquired oromandibular dystonia may persist in sleep).
   What is the medical definition of oromandibular dystonia?
   Oromandibular dystonia may be primary (meaning that it is the only apparent neurological disorder, with or without a family history) or be brought about by secondary causes such as drug exposure or disorders such as Wilson’s disease. Cases of inherited cranial dystonia have been reported, often in conjunction with DYT1 generalized dystonia.
   Can BTX treat oromandibular dystonia?
   Oromandibular dystonia is among the most challenging forms of focal dystonia to treat with BTX (Blitzer et al., 1989); it rarely improves with medications, there are no surgical treatments, and BTX therapy can be complicated by swallowing problems.
   How to treat oromandibular dystonia?
   Oromandibular dystonia may respond surprisingly well to the use of sensory tricks to temporarily reduce symptoms. For example, gently touching the lips or chin, chewing gum, talking, biting on a toothpick, or placing a finger near an eye or underneath the chin may cause symptoms to subside temporarily.
   What is the Robot Syndrome?
   The Robot Syndrome is how you feel when you repeat the same activities over and over again.
   What is Athymhormia?
   It is a disorder of motivation, one of that class of neuro – psychiatric conditions marked by abnormalities or deficiencies in motivation. Symptoms include the loss or reduction of desire and interest toward previous motivations, loss of drive and the desire for satisfaction, curiosity, the loss of tastes and preferences, and flat affect.
   What is Rocket Sign?
   The so-called rocket sign is a toppling backwards, after jumping to the feet from
   the sitting position, due to postural instability, seen in progressive supranuclear
   palsy (PSP) and ascribed to frontal lobe dysfunction. A history of falls due to
   postural instability in the first year after disease onset is one of the mandatory
   inclusion criteria for the diagnosis of PSP.
   What is Roger’s Sign?
   Roger’s sign, or the numb chin syndrome, is an isolated neuropathy affecting the
   mental branch of the mandibular division of the trigeminal (V) nerve, causing
   pain, swelling, and numbness of the lower lip, chin, and mucous membrane inside
   the lip. This is usually a sign of metastatic spread of cancer to the jaw.
   Hypoaesthesia involving the cheek, upper lip, upper incisors, and gingiva,
   due to involvement of the infraorbital portion of the maxillary division of the
   trigeminal nerve (‘numb cheek syndrome’), is also often an ominous sign, resulting from recurrence of squamous cell carcinoma of the face infiltrating the nerve.
   What is ‘Rolex’ Sign?
   Apparent malfunction of self-winding (Rolex) watches, which depend on movement of the arm, may occur when they are worn on a hypokinetic, rigid arm; this may be the first sign of a parkinsonian syndrome.
   What is Wartenberg’s Sign?
   It refers to the slightly greater abduction of the fifth digit, due to paralysis of the abducting palmar interosseous muscle and unopposed action of the radial innervated extensor muscles (digiti minimi, digitorum communis ).This should not be confused with Wartenberg’s Syndrome which is described as the entrapment of the superficial branch of the radial nerve with only sensory manifestations and no motor deficits.
   What is Rombergism, Romberg’s Sign?
   Romberg’s sign is adjudged present (or positive) when there is a dramatic increase
   in unsteadiness, sometimes with falls, after eye closure in a patient standing comfortably (static Romberg’s test). Before asking the patient to close his or her eyes,
   it is advisable to position ones arms in such a way as to be able to catch the
   patient should they begin to fall. Patients may fall forward immediately on eye
   closure (‘sink sign’). These phenomena result from sensory ataxia (i.e. loss of proprioception from the feet), which occurs most commonly with posterior column
   spinal cord disease: Romberg’s sign may be seen in tabes dorsalis.
   A modest increase in sway on closing the eyes may be seen in normal subjects
   and patients with cerebellar ataxia, frontal lobe ataxia, and vestibular disorders
   (towards the side of the involved ear); on occasion these too may produce an
   increase in sway sufficient to cause falls. Hence, Romberg’s test is not specific.
   Post urography is an attempt to quantify the Romberg test.
   Large amplitude sway without falling, due to the patient clutching hold of
   the physician, has been labelled ‘psychogenic Romberg’s sign’, an indicator of
   functional stance impairment.
   Heel–toe (tandem) walking along a straight line is sometimes known as the dynamic Romberg’s test.
   What is tandem walking?
   Tandem gait is a gait (method of walking or running) where the toes of the back-foot touch the heel of the front foot at each step. Neurologists sometimes ask patients to walk in a straight line using tandem gait as a test to help diagnose ataxia, especially truncal ataxia, because sufferers of these disorders will have an unsteady gait.
   What is Roos Test?
   Roos test, or the elevated arm stress test, may be helpful in the diagnosis of vascular thoracic outlet syndrome, along with Adson’s test. The arm is held above the
   head with the elbow extended and the hand exercised. Development of numbness,
   pain, and paraesthesia, along with pallor of the hand, supports the diagnosis of
   thoracic outlet syndrome.
   What is Rooting Reflex?
   The rooting reflex is a turning of the head towards a tactile stimulus on the face
   or an object approaching the mouth, a normal response in infants which is lost
   during childhood. Its presence in adults is indicative of diffuse premotor frontal
   disease, this being a primitive reflex or frontal release sign.
   What is Adson syndrome?
   Limitations, and pathophysiology of thoracic outlet syndrome. Adson’s sign is no longer used as a positive diagnosis of TOS since many people without TOS will show a positive Adson’s. There is minimal evidence of inter examiner reliability. Thoracic outlet obstruction may be caused by a number of abnormalities.
   What is Adson s sign?
   Adson’s sign is the loss of the radial pulse in the arm by rotating head to the ipsilateral side with extended neck following deep inspiration. It is sometimes used as a sign of thoracic outlet syndrome (TOS).
   What is Adson maneuver?
   Adson’s Test, also known as Adson’s Maneuver, is a test used in orthopaedic examination of the shoulder when testing for thoracic outlet syndrome. Involved Structures. Starting Position. The test can be performed with the patient in either sitting or standing with their elbow in full extension. As usual, it is best to test both sides for comparison.
   What is Rosnebach’s sign?
   It indicates unusual tremor of the eyelids which is often associated with various diseases involving high levels of thyroxine. What are the diseases associated with Rosenbach’s sign? 1. Grave’s disease 2. Hyperthyroidism 3. Thyroid storm
   What is Ross syndrome?
   Ross’ syndrome consists of Adie’s syndrome (myotonic pupils and absent deep tendon reflexes) plus segmental anhidrosis (typically associated with compensatory hyperhidrosis).
   What is Saccades?
   Saccades are rapid, ballistic, yoked movements of the eyes which bring the gaze
   to a new location in visual space. These movements may be performed voluntarily (tested clinically by asking the patient to ‘Look to your left, keeping your
   head still’, etc.) or reflexively, i.e. in response to an object of potential interest within the visual field (tested clinically by asking the patient to shift gaze
   from one of examiner’s hands to another). Internuclear ophthalmoplegia may be
   revealed when testing saccadic eye movements.
   What is Saccadic Intrusion, Saccadic Pursuit?
   Saccadic intrusions are inappropriate saccades which interfere with visual fixation (static, or during motor pursuit: saccadic pursuit). Several types of saccadic
   intrusion are described, including ocular flutter, opsoclonus, and square wave
   jerks. Saccadic (cogwheel) pursuit is normal in infants and may be a non-specific
   finding in adults; however, it may be seen in Huntington’s disease.
   What is Saccadomania?
   Opsoclonus refers to uncontrolled, irregular, and nonrhythmic eye movement. Opsoclonus consists of rapid, involuntary, multivectorial (horizontal and vertical), unpredictable, conjugate fast eye movements without inter-saccadic intervals. It is also referred to as saccadomania or reflexive saccade.
   What is saddle anesthesia?
   Saddle anesthesia is a loss of sensation (anesthesia) restricted to the area of the buttocks, perineum and inner surfaces of the thighs. It is frequently associated with the spine-related injury cauda equina syndrome. It is also seen in conus medullaris; the difference is that it is symmetrical in conus medullaris and asymmetric in cauda equina.
   What is Sacral Sparing?
   Sacral sparing is the preservation of pain and temperature sensation in sacral
   dermatomes when there is loss in the legs and trunk. This is a late, unusual, but
   diagnostic feature of a spinal cord lesion, usually an intrinsic (intramedullary)
   lesion but sometimes an extramedullary compression. Spastic paraparesis below
   the level of the lesion due to corticospinal tract involvement is invariably present
   by this stage of sacral sparing.
   Sacral sparing is explained by the lamination of fibres within the spinothalamic tract: ventrolateral fibres (of sacral origin), the most external fibres, are involved later than the dorsomedial fibres (of cervical and thoracic origin) by an expanding central intramedullary lesion (e.g. glioma, ependymoma, syringomyelia). Although sacral sparing is rare, sacral sensation should always be checked in any patient with a spastic paraparesis.
   What is Saturday night syndrome?
   Saturday night palsy is a term used to describe a person waking up with muscle paralysis in their arm. Usually the person drank an excessive amount of alcohol and passed out with an arm outstretched across a hard support or back of a chair.
   What are the types of wrist drop?
   Types of wrist drop are distinguished by the nerves affected: 1 Weakness of brachioradialis, wrist extension and finger flexion = radial nerve lesion 2 Weakness of finger extension and radial deviation of the wrist on extension = posterior interosseous nerve lesion 3 Weakness of triceps, finger extensors and flexors = c7,8 lesion 4 General weakness of upper limb marked in deltoid, triceps, wrist extension and finger extension = corticospinal lesion.
   What causes wrist drop and wrist fracture?
   Fractures of the elbow joint or the upper arm (humerus bone) can also cause radial nerve injury and Wrist Drop. Wearing tight bracelets can also cause injury to the radial nerve resulting in a Wrist Drop.
   What causes scapula winging?
   Scapula winging is caused by severe injury to the muscles that control the scapula or to the nerves that supply these muscles. One common cause is injury to the serratus anterior muscle. Without this muscle, the arm cannot be raised above shoulder level.
   Is a scapula alata always painful?
   Most of these patients describe a sever or excruciating pain, often keeping them awake. Most of the painful scapula alata are caused by a neurological trauma. But a winged scapula is not always painful, this is often with a muscular scapula alata.
   What is Savant Syndrome?
   Savant syndrome, previously idiot savant syndrome, refers to individuals with
   developmental disability yet displaying skills at a level inconsistent with their
   general intellectual functioning. The outstanding ability may be feats of memory
   (recalling names), calculation (especially calendar calculation), music, or artistic skills, often in the context of autism or pervasive developmental disorder.
   Obsolete classification of such abilities as superlative technical skill, hypermnesia, calculating idiots, and calendar artists has been superseded by interest in
   how the disparities between these and general intellectual abilities come about
   and whether this is some form of ‘release’ phenomenon. Occasionally, skills
   such as artistic ability may emerge in the context of neurodegenerative disease
   (Alzheimer’s disease, frontotemporal lobar degeneration).
   What is Scanning Speech?
   Scanning speech is a motor speech disorder (i.e. a dysarthria) comprising slow,
   deliberate, dysprosodic, monotonic verbal output. It may be confused with nonfluent aphasia (Broca’s aphasia).
   Scanning speech was originally considered a feature of cerebellar disease in
   multiple sclerosis (after Charcot), and the term is often used with this implication. However, cerebellar disease typically produces an ataxic dysarthria (variable
   intonation, interruption between syllables, ‘explosive’ speech) which is somewhat different from scanning speech. Scanning speech correlates with midbrain
   lesions, often after recovery from prolonged coma.
   What is Schizophasia?
   This term has been used to describe the language disorder in schizophrenia,
   which may be characterized by paraphasias and neologisms, loose connections
   between thoughts, tangential thinking, and delusional intrusions. The resulting
   output may be unintelligible and may resemble Wernicke’s aphasia.
   What is Schwabach Test?
   In the Schwabach test, a vibrating tuning fork is held against the patient’s mastoid process, as in Rinne’s test, until it is no longer audible. The examiner then
   places the tuning fork over his/her own mastoid, hence comparing bone conduction with that of the patient. If still audible to the examiner (presumed to have normal hearing), a sensorineural hearing loss is suspected, whereas in conductive hearing loss the test is normal.
   What is Rinne test?
   It is a hearing test, primarily for evaluating loss of hearing in one ear (unilateral hearing loss). It compares perception of sounds transmitted by air conduction to those transmitted by bone conduction through the mastoid. Thus, one can quickly screen for the presence of conductive hearing loss.
   What is degenerative scoliosis?
   Degenerative scoliosis is a condition that refers to an abnormal curvature of the spine that occurs in a patient over the age of 18. It typically develops as joints in the spine degenerate and causes the spine to bend. Another term often used to describe the condition is adult scoliosis.
   What is Scotoma?
   A scotoma is a localized area of impaired vision within an otherwise normal
   visual field. Mapping of the defect may be performed manually, by confrontation
   testing, or using an automated system. In addition to the peripheral field, the central field should also be tested, with the target object moved around the fixation
   point. A central scotoma may be picked up in this way or a more complex defect
   such as a centrocaecal scotoma in which both the macula and the blind spot
   are involved. Infarction of the occipital pole will produce a central visual loss,
   as will optic nerve inflammation. Scotomata may be absolute (no perception of
   form or light) or relative (preservation of form, loss of colour). Blindsight may
   fall into the latter category. A scotoma may be physiological, as in the blind spot
   or angioscotoma, or pathological, reflecting disease anywhere along the visual
   pathway from retina and choroid to visual cortex. Various types of scotoma may
   be detected:
   • Central scotoma;
   • Caecocentral or centrocaecal scotoma;
   • Arcuate scotoma;
   • Annular or ring scotoma;
   • Junctional scotoma;
   • Junctional scotoma of Traquair;
   • Peripapillary scotoma (enlarged blind spot).
   What is a visual field defect?
   Visual field defects that respect the horizontal meridian are associated with defects of the retina or optic nerve. There are rare case reports of non-arteritic ischemic optic neuropathy (NAION) and glaucoma causing heteronymous altitudinal visual field defects and resulting retinal hemified slide phenomenon.
   What is inferior frontal defect?
   Either superior or inferior defects; traumatic injury (most commonly from bullet wounds) usually causes only bilateral inferior altitudinal field defects. This is because damage to the lower portion of the occipital lobes; which would produce bilateral superior altitudinal defects; often results in laceration of the dural sinuses; with almost fatal.
   What causes longitudinal defect?
   Altitudinal field defect may be unilateral or bilat- eral. The main causes are as follows: RETINAL CAUSES 1. Branch Retinal Artety Occlusion 2. Branch Retinal Vein Occlusion 3. Retinal Coloboma OPTIC NERVE LESION 1. Ischaemic optic neuropathy (both arteritic and non-arteritic types)
   What is Retinitis pigmentosa (RP)?
   It is a genetic disorder of the eyes that causes loss of vision. Symptoms include trouble seeing at night and decreased peripheral vision (side vision). As peripheral vision worsens, people may experience “tunnel vision”.
   What is Scratch Test?
   The ‘scratch test’, or ‘direction of scratch’ test, examines perception of the direction (up or down) of a scratch applied to the anterior shin (for example, with
   the sharp margin of a paper clip). It has been claimed as a reliable test of posterior column function of the spinal cord. Errors in this test correlate with central
   conduction times and vibration perception threshold.
   What is Seborrhoea?
   Seborrhoea is a greasiness of the skin which may occur in extrapyramidal
   disorders, particularly Parkinson’s disease.
   What is Seizures?
   Seizures are sudden, paroxysmal episodes of neurological dysfunction with or
   without impairment of consciousness, which may be epileptic (i.e. due to abnormal synchronous electrical activity within the brain, either focally or generally)
   or non-epileptic in origin (‘pseudo seizures’, non-epileptic attack disorder). The
   two varieties may coexist. Seizure morphology may be helpful in establishing
   aetiology and/or focus of onset.
   • Epileptic:
   Idiopathic generalized: tonic–clonic (‘grand mal’); absence attack (‘petit
   mal’); myoclonic epilepsy.
   Partial: simple (no impairment of consciousness), for example, jerking of one arm, which may spread sequentially to other body parts
   (Jacksonian march); or complex, in which there is impairment or loss
   of consciousness: may be associated with specific aura (olfactory, déjà
   vu, jamais vu) and/or automatisms (motor, e.g. cursive; or emotional,
   e.g. gelastic, dacrystic); limb posturing (salutatory, fencing posture)
   and pelvic thrusting may be seen in frontal lobe epilepsy. Secondary
   generalization of seizures of partial onset may occur.
   Investigation of partial seizures to exclude a symptomatic cause is recommended (MR imaging, EEG). Some are amenable to surgical intervention.
   Otherwise, as for idiopathic generalized epilepsies, various antiepileptic medications are available. Partial seizures may prove more resistant to treatment than
   generalized seizures.
   • Non-epileptic:
   Often long lasting, thrashing, pelvic thrusting, carpet burns, eyes closed
   and resist opening, tongue biting rare, may have incontinence; past
   history of physical or sexual abuse. Best treated with psychological approaches or drug treatment of underlying affective disorders;
   antiepileptic medications are best avoided.
   The differentiation of epileptic from non-epileptic seizures may be difficult;
   it is sometimes helpful to see a video recording of the attacks or to undertake
   in-patient video-telemetry.
   What is Self-Mutilation?
   Self-injury to the point of mutilation, especially around the mouth, may be seen
   in certain neurological conditions, such as Lesch–Nyhan syndrome, Tourette
   syndrome, and Neuroacanthocytosis.
   What is Referred Pain?
   “Referred pain” occurs when visceral pain, for example from angina (pain arising from heart muscle that does not have an adequate blood supply), is felt as cutaneous pain, for example, in the left arm and hand.
   Referred pain occurs because there are few, if any, neurons in the dorsal horn that solely send signals of visceral pain to the brain. Thus, neurons sending signals from the viscera, are also involved in sending signals of cutaneous pain, resulting in potential confusion of the source of the pain.
   What is pelvic Kegel exercise?
   Share on Pinterest Pelvic exercises can help improve the function of pelvic muscles. Kegel exercises focus on tightening and holding the muscles that control urine flow. This exercise is suitable for men and women. A Kegel exercise consists of the following steps:
   What is geste antagoniste?
   It is a physical gesture or position (such as touching one’s chin) that temporarily interrupts dystonia, it is also known as a sensory trick. Patients may be aware of the presence of a geste antagoniste that provides some relief. Therapy for dystonia can involve prosthetics that passively simulate the stimulation.
   What is Sequential Paresis?
   Sequential, or ‘round the clock’, paresis or weakness refers to the sequential
   development of weakness in one arm, the ipsilateral leg, the contralateral leg, and
   contralateral arm (i.e. hemiparesis, triparesis, tetraparesis or quadriparesis). This
   pattern is highly suggestive of a foramen magnum lesion, usually a tumour but
   sometimes demyelination or other intrinsic inflammatory disorder, sequentially
   affecting the lamination of corticospinal fibres in the medullary pyramids.
   What is Setting Sun Sign?
   The setting sun sign, or sunset sign, consists of tonic downward deviation of the eyes with retraction of the upper eyelids exposing the sclera. There may be down beating nystagmus. Setting sun sign is a sign of dorsal midbrain compression in children with untreated hydrocephalus.
   A similar appearance may also be observed in progressive supranuclear palsy
   (Steele–Richardson–Olszewski syndrome; Stellwag’s sign) and in Parinaud’s
   syndrome, but without the tonic downward deviation.
   What is Stellwag’s sign?
   It is a sign of infrequent or incomplete blinking associated with exophthalmos or Graves orbitopathy. It is accompanied by Dalrymple’s sign, which is a retraction of the upper eyelids resulting in an apparent widening of the palpebral opening. Stellwag’s sign is named after Austrian ophthalmologist Karl Stellwag von Carion.
   What is a heel shin test?
   heel-shin test. Etymology: AS, hela + scinu, shin; L, testum, crucible. a cerebellar test for assessing coordination of movements of the extremities. In the test, the patient, lying supine, is asked to pass the heel of one leg slowly down the shin of the other leg from the knee to the ankle.
   What is Shadowing?
   A neurobehavioral disorder, occasionally seen in patients with dementia, in which the patient follows the spouse or carer around like a shadow.
   What is Shin-Tapping?
   A modification of the heel–knee–shin test or heel–shin test in which the heel is
   tapped repetitively on the shin before sliding it down to the foot, claimed to be a
   better test of motor coordination.
   What is Sialorrhoea?
   Sialorrhoea (drooling) is excessive salivation, possibly due to excess flow of
   saliva but more likely secondary to a reduced frequency of swallowing (e.g. in
   parkinsonian syndromes) or difficulty in swallowing (e.g. motor neurone disease,
   developmental perisylvian syndrome). Metallic poisonings (mercury, bismuth,
   lead) may also produce marked salivation (ptyalism).
   If troublesome, treatment of Sialorrhoea with anticholinergic agents may be
   tried (atropine, hyoscine), although they may cause confusion in Parkinson’s disease. In extreme cases, irradiation of the salivary glands has been used. Recently,
   the use of intraparotid injections of botulinum toxin has been found useful.
   What is Sighing?
   Occasional deep involuntary sighs may occur in multiple system atrophy. Sighing
   is also a feature, along with yawning, of the early (diencephalic) stage of central herniation of the brainstem with an otherwise normal respiratory pattern.
   Sudden inspiratory or expiratory sighs are said to be a feature of the hyperkinetic choreiform dysarthria characteristically seen in choreiform disorders such as Huntington’s disease.
   What is fan sign?
   Signe de l’éventail is the fanning of the toes on eliciting Babinski’s plantar sign. In most instances, great toe extension is the most prominent component of the abnormal plantar response. Fanning of the smaller toes is typically less conspicuous if noticeable at all. In this case, the fanning was more prominent that the great toe extension
   What is Signe de Rideau?
   Signe de rideau, or curtain sign, refers to the motion of the posterior pharyngeal
   wall towards the intact side, resembling the drawing of a curtain, in unilateral
   paresis of the superior pharyngeal constrictor muscle, as seen in unilateral vagus (X) nerve palsy.
   What is Froment’s sign?
   It is a physical examination of the hand to test for palsy of the ulnar nerve which results in reduced functionality and muscle weakness of the pinch grip. It tests the strength of the adductor pollicus of the thumb, which is innervated by the ulnar nerve and is weakened in ulnar nerve palsy.
   What is the word family for simian?
   The simians or anthropoids are an infraorder (Simiiformes) of primates containing the parvorders Patyrrhini and Catarrhini, which consists of the super families Cercopithecoidea and Hominoidea (including the genus Homo). The simians are sister to the tarsiers, together forming the haplorhines.
   What is Simian Posture?
   The arms hang down and are rotated internally so that the thumbs point toward the patient (ie, simian posture) rather than forward, as in a healthy individual. This observation strongly suggests weakness in shoulder girdle muscles. Fasciculations, or spontaneous discharges of single motor units, are seen easily in affected musculature.
   What is Simian Hand?
   Simian hand or ape hand has been used to describe the atrophy of the thenar
   eminence with recession of the metacarpal bones of the thumb to the plane of
   the other metacarpal bones seen in median nerve lesions in the axilla or upper arm.
   What is Simultanagnosia?
   Simultanagnosia is impaired perception of multi-element or multipart visual displays, such that pictures are described in a piecemeal manner. Recognition of single objects is preserved; this is likened to having a fragment or island of clear vision which may shift from region to region. Two types of simultanagnosia are described:
   • Dorsal:
   An attentional limitation preventing more than one object being
   seen at a time; although superficially similar to apperceptive visual
   agnosia, with which it has sometimes been classified, patients with dorsal simultanagnosia can recognize objects quickly and accurately, but
   unattended objects are not seen. There may be inability to localize stimuli even when they are seen, manifest as visual disorientation. Reading
   is severely impaired. Patients may grope, as though blind. Dorsal
   simultanagnosia is associated with bilateral posterior parieto-occipital
   lesions and is one feature of Balint’s syndrome.
   • Ventral:
   A limitation in the number of objects which can be recognized in unit
   time, i.e. there is no primary recognition problem in that individual
   shapes can be recognized. Ventral simultanagnosia is most evident during reading which is severely impaired and empirically this may be the
   same impairment as seen in pure alexia; otherwise deficits may not be
   evident, unlike dorsal simultanagnosia. Ventral simultanagnosia may
   be a form of associative visual agnosia. It is associated with left inferior
   temporooccipital cortical lesions.
   What is Singultus?
   Singultus or hiccough is the state of having reflex spasms of the diaphragm accompanied by a rapid closure of the glottis producing an audible sound; sometimes a symptom of indigestion
   What is the difference between hypertropia and hypotropia?
   Hypertropia is a condition of misalignment of the eyes (strabismus), whereby the visual axis of one eye is higher than the fellow fixating eye. Hypotropia is the similar condition, focus being on the eye with the visual axis lower than the fellow fixating eye.
   What is barber chair phenomenon?
   Lhermitte phenomenon, also called the barber chair phenomenon, is an uncomfortable “electrical” sensation that runs through the back and into the limbs. The sensation can feel like it goes up or down the spine.
   In many people, it is elicited by bending the head forward. It can also be evoked when a practitioner pounds on the cervical spine while the neck is flexed; this is caused by involvement of the posterior columns.
   Lhermitte phenomenon is named for French neurologist Jean Lhermitte.
   The sign suggests a lesion or compression of the upper cervical spinal cord or lower brainstem—usually dorsal columns of the cervical cord or caudal medulla.
   Although often considered a classic finding in multiple sclerosis, it can be caused by a number of conditions, including transverse myelitis, Behçet disease, osteogenesis imperfecta, trauma, radiation myelopathy,[ vitamin B12 deficiency (subacute combined degeneration), compression of the spinal cord in the neck from any cause such as cervical spondylosis, disc herniation, tumor, and Arnold–Chiari malformation. Lhermitte’s sign may also appear during or following high-dose chemotherapy. Irradiation of the cervical spine may also evoke it as an early delayed radiation injury, which occurs within 4 months of radiation therapy.
   Delayed onset Lhermittes sign has been reported following head and/or neck trauma. This occurs ~2 1/2 months following injury, without associated neurological symptoms or pain, and typically resolves within 1 year.
   This sign is also sometimes seen as part of a “discontinuation syndrome” associated with certain psychotropic medications, such as selective serotonin reuptake inhibitors and serotonin norepinephrine reuptake inhibitors, particularly paroxetine and venlafaxine. Typically, it only occurs after having taken the medication for some duration, and then stopped or withdrawn rapidly or after administering reduced dose. Fluoxetine, given its very long half-life, can be given as a single small dose, and often avoid Lhermitte’s sign and other withdrawal symptoms.
   What is Skew Deviation?
   Skew deviation, or the Hertwig–Magendie sign, is a supranuclear vertical misalignment of the visual axes; the final common efferent pathway for eye movements is spared (cf. hypertropia, hypotropia, due to ocular motor nerve palsies or extraocular muscle disease). This is thought to reflect damage to otolith-ocular pathways or vestibulo-ocular pathways. There may be concurrent ocular tilt reaction. Bielschowsky’s head tilt test is usually negative (cf. ocular motor nerve palsies).
   Skew deviation has been associated with posterior fossa lesions, from midbrain to medulla. Ipsiversive skew deviation (ipsilateral eye lowermost) has been associated with caudal pontomedullary lesions, whereas contraversive skew (contralateral eye lowermost) occurs with rostral pontomesencephalic lesions, indicating that skew type has localizing value.
   What is the Parks–Bielschowsky three-step test?
   It, also known as Park’s three-step test or Bielschowsky head tilt test, is a method used to isolate the paretic extraocular muscle, particularly superior oblique muscle and trochlear nerve (IVth cranial nerve), in acquired vertical double vision. It was originally described by
   What is the Tullio phenomenon?
   Tullio phenomenon, sound-induced vertigo, dizziness, nausea or eye movement ( nystagmus) was first described in 1929 by the Italian biologist Prof. Pietro Tullio. (1881–1941) During his experiments on pigeons, Tullio discovered that by drilling tiny holes in the semicircular canals of his subjects, …
   What is Smile–Wink Phenomenon?
   This name has been given to narrowing of the palpebral fissure aggravated by
   smiling following a contralateral lenticulocapsular infarction. Dysarthria, facial
   paresis, hemiparesis with or without hemihypoaesthesia, and excessive laughing
   with or without crying were common accompanying features in one series.
   What is Sneezing?
   Sneezing, or ptarmus, or sternutation, is a complex respiratory reflex. Sensory
   nasal trigeminal afferents run to a putative sneeze centre, localized to the brainstem based on lesions causing loss of sneezing following lateral medullary
   syndrome and medullary neoplasm. Integration of inputs in this centre reaches a
   threshold at which point an expiratory phase occurs with exhalation, forced eye
   closure, and contraction of respiratory musculature.
   Sneezing may also be triggered by the presence of light: photoptarmosis or the photic sneeze reflex.
   What is Snoring?
   Reduced muscle tone in the upper airway during sleep leads to increased resistance to the flow of air, and partial obstruction often results in loud snoring.
   This symptom may be associated with the obstructive sleep apnoea–hypopnoea
   syndrome (OSAHS), risk factors for which include obesity, alcohol overconsumption, and male sex. OSAHS may be associated with a variety of neurological
   symptoms including excessive daytime somnolence, episodic loss of consciousness, headache (especially morning), cognitive decline, and increased risk of
   stroke (snoring may be an independent risk factor for stroke).
   What is Hypersomnolence?
   Hypersomnolence is marked by excessive and chronic daytime sleepiness. People who suffer this disorder do not enjoy restorative night-time sleep, though some individuals sleep up to seven hours a night. These sufferers nap throughout the day—at work, sitting down at dinner, and even at social events.
   What causes hypersomnia in adults?
   There are several potential causes of hypersomnia, including: The sleep disorders narcolepsy (daytime sleepiness) and sleep apnea (interruptions of breathing during sleep) Not getting enough sleep at night (sleep deprivation)
   What is palmomental reflex?
   Palmomental Reflex. When the palmomental reflex is present, the mentalis muscle of the chin below the lower lip contracts when the palm is stroked (see Video 2-7). The stroke in the palm may be performed by gently flicking the thumbnail from lower ulnar surface of the palm, up and across the palm to the base of the index finger.
   What is Snouting, Snout Reflex?
   Sometimes used interchangeably with pout reflex, this term should probably be
   reserved for the puckering or pouting of the lips induced by constant pressure
   over the philtrum, rather than the phasic response to a tap over the muscle with
   finger or tendon hammer. The Snout reflex or a ” Pout ” is a pouting or pursing of the lips that is elicited by light tapping of the closed lips near the midline. The contraction of the muscles causes the mouth to resemble a snout. This reflex is tested in a neurological exam and if present, is a sign of brain damage or dysfunction.
   What are the conditions that cause confabulation?
   Examples of conditions that can cause confabulation include: 1 anosognosia for hemiplegia, or denial of paralysis. 2 Anton’s syndrome, or denial of blindness. 3 Capgras syndrome, or the belief that an imposter has replaced a loved one. 4 Korsakoff syndrome. 5 memory disorders, such as dementia and Alzheimer’s disease. 6 schizophrenia. 7 split-brain syndromes. 8 traumatic brain injury.
   What is Somatoparaphrenia?
   Ascription of hemiplegic limb(s) to another person (e.g. the examiner, a family
   member). This may be a form of asomatognosia, or possibly a confabulation.
   What is Autotopagnosia?
   It is a form of agnosia, characterized by an inability to localize and orient different parts of the body. The psychoneurological disorder has also been referred to as “body-image agnosia” or “somatotopagnosia.
   What is Spasm?
   The word spasm implies a sudden, involuntary, muscle contraction, which may be
   painful (cramp). For example, flexor spasms in patients paraplegic due to upper
   motor neurone lesions are sudden contractions of the flexor musculature, particularly of the legs, either spontaneous or triggered by light touch. Hemifacial spasm
   is an involuntary contraction of facial musculature. Tonic spasms (paroxysmal
   dystonia) occur in multiple sclerosis.
   Spasm may also refer to a tetanic muscle contraction (tetany), as seen in
   hypocalcaemic states (e.g. main d’accoucheur), tetanus (e.g. risus sardonicus), or
   tonic spasms of various muscles (e.g. jaw musculature, trismus) which may be
   dystonic or spastic in origin. Involuntary movements such as tics may be known
   as spasms or habit spasms.
   Patients may use the word spasm differently, e.g. to denote paroxysmal sensory phenomena, or even epileptic seizures. Infantile seizures consisting of brief
   flexion of the trunk and limbs (emposthotonos, salaam or jack-knife seizures)
   may be known as spasms.
   What does trismus mean?
   It is motor disturbance of the trigeminal nerve, especially spasm of the masticatory muscles, with difficulty in opening the mouth (lockjaw); a characteristic early symptom of tetanus. Trismus is the medical term for “lock-jaw,” a condition that causes the muscles in the jaw, known as the muscles of mastication, to spasm or contract uncontrollably. Trismus lockjaw is commonly associated as an effect of tetanus infection but can be the result of a few causes.
   What causes trismus lockjaw?
   Trismus has a variety of causes, and can occur from nerve, muscle, or joint problems. Trismus or lockjaw is an early symptom of tetanus, but is most frequently caused by radiation to the face, jaw, mouth or nose for cancer therapy.
   What is Spasmus Nutans?
   Spasmus nutans is the clinical triad of head nodding, anomalous head postures,
   and nystagmoid eye movements seen in children aged between 1 and 8 years.
   This is usually a benign idiopathic condition, but the diagnosis should prompt
   consideration of an optic pathway tumour.
   What is “spastic catch,”?
   “Spastic catch,” exhibit the “clasped knife” phenomenon, or both. Observing the person with spasticity perform activities such as walking, drinking from an open cup, and moving from one position to another often yields valuable information.
   What is spastic diplegia?
   Spastic diplegia is the lower extremities affected, with little to no upper-body spasticity. The most common form of the spastic forms (70–80% of known cases), most people with spastic diplegia are fully ambulatory, but are “tight” and have a scissors gait.
   What is Spasticity?
   Spasticity is an increased resistance to the passive movement of a joint due to
   abnormally high muscle tone (hypertonus) which varies with the amplitude and
   speed of displacement of a joint (cf. rigidity). The excessive resistance evident at
   the extremes of joint displacement may suddenly give way, a phenomenon known
   as clasp-knife (or, confusingly, clasp-knife rigidity). Spasticity may vary in degree
   from mild (e.g. a spastic catch on supination/pronation of the forearm) to extreme
   (e.g. immobile limbs in fixed flexion with secondary contractures and painful
   spasms: paraplegia in flexion). Spasticity may need to be differentiated clinically
   from rigidity and stiffness.
   Treatment of severe spasticity, for example, in multiple sclerosis, often
   requires a multidisciplinary approach. Urinary infection, constipation, skin
   ulceration, and pain can all exacerbate spasticity, as may inappropriate posture; appropriate management of these features may ameliorate spasticity. Drugs
   which may be useful include baclofen, dantrolene (a blocker of muscle excitation–
   contraction coupling), and tizanidine (α2-adrenoreceptor agonist). Intrathecal
   baclofen given via a pump may also be of benefit in selected cases, and for focal
   spasticity injections of botulinum toxin may be appropriate. For painful immobile spastic legs with reflex spasms and double incontinence, irreversible nerve
   injury with intrathecal phenol or alcohol may be advocated to relieve symptoms.
   The place of cannabinoids has yet to be fully determined.
   What is hypertonus?
   Neurologic examination revealed normal cranial and spinal reflexes, but muscle tone of the hind limb was spastic, resulting in hypertonus.
   What is clonus and how does it occur?
   Clonus is a type of neurological condition that creates involuntary muscle contractions. This results in uncontrollable, rhythmic, shaking movements. People who experience clonus report repeated contractions that occur rapidly. It’s not the same as an occasional muscle contraction.
   What is a clonus in the foot?
   ankle clonus (foot clonus) a series of abnormal reflex movements of the foot, induced by sudden dorsiflexion, causing alternate contraction and relaxation of the triceps surae muscle.
   Is it normal for a newborn to have a clonus?
   Clonus can be physiologic, for instance, term infants can be hyperreflexic, and a few beats of clonus can be a normal finding in this population; however, most infants will not exhibit this finding, and most infants who will go on to demonstrate cerebral palsy will not exhibit clonus. Sustained clonus is never normal. Ankle clonus is easiest to obtain if the examiner grasps the foot from below and quickly pushes upward while maintaining slight pressure on the sole at the end of the movement. Patellar clonus consists of a series of rhythmic up-and-down movements of the patella elicited by a quick, downward thrust.
   What is Clasp-knife reflex?
   It is a response refers to a Golgi tendon reflex with a rapid decrease in resistance when attempting to flex a joint, usually during a neurological examination. It is one of the characteristic responses of an upper motor neuron lesion. It gets its name from the resemblance between the motion of the limb and the sudden closing of a clasp knife after sufficient pressure is applied.
   What is Speech Apraxia?
   Speech apraxia is one of the labels applied to a disorder of communication characterized by slow speech tempo (‘groping for words’), impaired articulation, and
   dysprosody, with relatively intact language function and no dysgraphia. More
   errors occur with increasing articulatory complexity (consonant clusters vs. single consonants). Automatic or reactive speech (e.g. expletives, cliches) is without
   error. This, or a very similar, constellation of features has also been known as
   cortical dysarthria, aphemia, or phonetic disintegration. There may be associated
   oro-facial apraxia.
   Speech apraxia has been associated with inferior frontal dominant (left)
   hemisphere damage in the region of the lower motor cortex or frontal operculum; it has been claimed that involvement of the anterior insula is specific for speech apraxia.
   The exact nosological status of this entity remains in some doubt. The syndrome is thought to reflect disturbances of planning articulatory and phonatory
   functions, but is most often encountered as part of a non-fluent aphasia.
   What is Spinal Mass Reflex?
   The spinal mass reflex is involuntary flexion of the trunk in a comatose patient,
   such that they appear to be attempting to sit up (‘rising from the dead’).
   What is Spoonerisms?
   This term is used for a speech production disorder characterized by the transposition of consonants, so named for the mannerism affecting the speech of Reverend WA Spooner, Warden of New College, Oxford (1844–1930). If not deliberate, it presumably reflects a left hemisphere dysfunction in the appropriate sequencing of phonemes.
   What is Spurling’s Sign?
   This is the name given to increase in arm pain (brachalgia) associated with compressive cervical radiculopathy following neck rotation and flexion to the side
   of the pain. A variant of this foraminal compression test involves rotation, side
   bend, and slight extension of the neck with the application of axial pressure to
   the head.
   What is Square Wave Jerks?
   Square wave jerks are small saccades which interrupt fixation, moving the eye
   away from the primary position and then returning. This instability of ocular
   fixation is a disorder of saccadic eye movements in which there is a saccadic
   interval (of about 200 ms; cf. ocular flutter, opsoclonus). Very frequent square
   wave jerks may be termed square wave oscillations. Very obvious square wave
   jerks (amplitude > 7◦) are termed macrosquare wave jerks.
   Square wave jerks are often best appreciated on ophthalmoscopy. Their name
   derives from the appearance they produce on electrooculographic recordings.
   Although square wave jerks may be normal in elderly individuals, they may
   be indicative of disease of the cerebellum or brainstem, e.g. Huntington’s disease, Parkinson’s disease, progressive supranuclear palsy, cerebellar degeneration
   including multiple system atrophy. They have been reported to have close to 100%
   sensitivity for the diagnosis of PSP.
   What is Stellwag’s Sign?
   Stellwag’s sign is a widening of the palpebral fissure due to upper eyelid retraction. Along with a reduced blink rate, this creates a very typical staring,
   ‘astonished’, facies. The clinical phenomena of Stellwag’s sign overlap with those
   labelled as the sunset sign. Stellwag’s sign is seen in progressive supranuclear
   palsy and in dysthyroid eye disease.
   What is Steppage, Stepping Gait?
   Steppage or stepping gait occurs with a lower motor neurone type of foot drop
   (‘floppy’ foot drop), e.g. due to a common peroneal nerve palsy, or peripheral
   neuropathies. Because of the weakness of foot dorsiflexion (weak tibialis anterior) there is compensatory overaction of hip and knee flexors during the swing
   phase of walking to ensure the foot clears the ground (hence ‘high-stepping gait’).
   In the strike phase, there is a characteristic slapping down of the foot, again a
   consequence of weak ankle dorsiflexion. Proprioceptive loss, as in dorsal column
   spinal disease, may also lead to a gait characterized by high lifting of the feet and
   also stomping (stamping with a heavily accented rhythm) or slapping of the foot
   onto the floor in the strike phase.
   The pattern of gait with upper motor neurone foot drop (‘stiff’ foot drop),
   e.g. due to a corticospinal tract lesion, is quite different, with the foot being
   dragged, sometimes with circumduction of the leg. This may lead to falls as
   a consequence of tripping over the foot, especially on up-hill gradients, and a
   characteristic pattern of wear on the point of the shoe.
   What are recurring utterances?
   Monophasia, recurring utterances, verbal stereotypy Neurology A form of motor aphasia, characterized by stereotyped utterances repeatedly repeated, as if by compulsion; an involuntary compulsion to perform a motor act Associations Psychomotor epilepsy, catatonic schizophrenia, psychogenic fugue, complex partial seizure, post-traumatic automatism, etc
   What is Stereotypy?
   Stereotypies, or adventitious movements, may be defined as regular repeated
   movements, which are voluntary but not apparently goal-directed, and which
   may be carried out in a uniform pattern for long periods of time (cf. tic). Whole
   areas of the body may be involved by stereotypies and hence this movement is
   more complex than a tic. Examples include patting, tapping, rubbing, clasping,
   wringing, digit sucking, body or head rocking or banging, grimacing, smelling,
   licking, spitting, and mouthing of objects.
   Stereotypies are common in patients with learning disability, autism, and
   schizophrenia. Very characteristic manual stereotypies (washing, rubbing movements: ‘hand washing’) may be seen in Rett’s disease. The term has also been
   used to describe movements associated with chronic neuroleptic use; indeed
   adult-onset stereotypy is highly suggestive of prior exposure to dopaminereceptor-blocking drugs.
   The recurrent utterances of global aphasia are sometimes known as verbal
   stereotypies or stereotyped aphasia. Reiterated words or syllables are produced by patients with profound non-fluent aphasia (e.g. Broca’s original case,
   Leborgne, who could only repeat ‘tan, tan, tan’, by which name he was known).
   What is Sternocleidomastoid Test?
   It has been reported that apparent weakness of the sternocleidomastoid muscle
   is common (80%) in functional hemiparesis, usually ipsilateral to the hemiparesis, whereas it is rare in vascular hemiparesis (11%), presumably because of the
   bilateral innervation of the muscle.
   What is Hyperacusis?
   It is a rare debilitating hearing disorder characterized by an increased sensitivity to certain frequencies and volume ranges of sound (a collapsed tolerance to usual environmental sound). A person with severe hyperacusis has difficulty tolerating everyday sounds, which become painful or loud.
   Is hyperacusis the same as recruitment?
   Patients suffering from hyperacusis may appear overly sensitive to a range of sounds, finding many noises unbearable and painfully loud. Hyperacusis is not the same as “recruitment,” a disorder that can be a normal consequence of hearing loss and is associated with abnormal perception of sound as the volume increases.
   What is rebound phenomenon in neurology?
   Stewart-Holmes sign – in cerebellar disease, the inability to check a movement when passive resistance is suddenly released
   What is the rebound phenomenon in drugs?
   . The rebound effect, or rebound phenomenon, is the emergence or re-emergence of symptoms that were either absent or controlled while taking a medication, but appear when that same medication is discontinued, or reduced in dosage.
   What is Stiffness?
   Stiffness of muscles occurs as a feature of all pyramidal and extrapyramidal
   disorders (as spasticity and rigidity, respectively), but the term stiffness is usually reserved for disorders in which stiffness is the principal symptom due to
   continuous motor unit activity within muscles. There may be associated muscle pain (cramp). Stiffness may be primarily of muscular origin (myotonia) or
   of neural origin (myokymia, neuromyotonia). Accompanying signs may prove
   helpful in diagnosis, such as slow muscle relaxation (myotonia), percussion irritability of muscle (myoedema), and spontaneous and exertional muscle spasms.
   Hyperlordotic posture is typical of stiff man/stiff person syndrome. Stiffness must
   be differentiated from both rigidity and spasticity. Recognized causes of stiffness
   include the following:
   • Stiff man/stiff person syndrome;
   • Stiff limb syndrome;
   • Progressive encephalomyelitis with rigidity +/− myoclonus;
   • Neuromyotonia (Isaac’s syndrome; armadillo syndrome; peripheral nerve
   hyperexcitability);
   • Schwartz–Jampel syndrome (chondrodystrophic myotonia);
   • Tetanus;
   • Strychnine poisoning.
   The stiff man/stiff person syndrome is probably of autoimmune pathogenesis
   since it is strongly associated with insulin-dependent diabetes mellitus and the
   presence of antibodies to glutamic acid decarboxylase (anti-GAD antibodies),
   the enzyme in the synthetic pathway of GABA. Intravenous immunoglobulin
   therapy may be of symptomatic benefit.
   What is Stork Legs?
   A name given to describe the disproportionate wasting of the lower legs, a
   pattern characteristic of hereditary motor and sensory neuropathies (Charcot–
   Marie–Tooth diseases), which may be evident even before the development of
   gait disorder with foot drop and steppage gait.
   What are the causes of foot drop?
   A foot drop typically occurs due to weakness in specific muscles of the leg. These muscles include
   Tibialis anterior
   Extensor hallucis longus
   Extensor digitorum longus
   The tendons of these muscles insert into the bones of the foot and/or toes, resulting in foot weakness and difficulty in lifting the foot and/or toes upward and in other directions.
   Nerves in the lower back and/or leg may be pinched or may get damaged and degenerated, causing foot drop.
   Irritation or compression of spinal nerve roots in the lumbar and/or sacral spine may cause foot drop due to radiculopathy. The symptoms of radiculopathy typically include weakness, pain, tingling, and/or numbness in the skin and/or muscles supplied by the affected nerve.
   Foot drop is commonly caused by radiculopathy of the L5 nerve root. Sometimes, radiculopathy from L4 and/or S1 may also cause foot drop.2 Radiculopathy occurs due to:
   Herniated disc. Bulging or leaking of the inner gelatinous contents of an intervertebral disc causing mechanical compression or chemical irritation of the adjacent nerve root.
   Foraminal spinal stenosis. Narrowing of the small bony openings for spinal nerves on the side of the spine due to abnormal bone growth (bone spurs) or degenerative changes, causing pressure on the nerve roots.
   Spondylolisthesis. Slipping of one vertebra over the adjacent lower vertebra due to degeneration or stress may compress a nerve root in between the vertebrae.
   The symptoms of radiculopathy typically affect one foot, sometimes, both feet may be affected when nerve roots on either side of the spine are compressed, such as in spondylolisthesis or severe herniation.
   When a nerve is compressed, damaged, or degenerated along its path, it is called neuropathy. Foot drop commonly occurs due to neuropathy of the following nerves:
   Common peroneal nerve. Neuropathy of this nerve may occur due to trauma to the knee, fracture of the fibula bone, pressure from tight boots or plaster, excessive weight loss, ankle sprain, or as a complication of knee surgery.3,4
   Deep peroneal nerve. Neuropathy of this nerve may occur due to increased pressure within the muscle bundles of the leg or compartment syndrome, fracture of the leg’s tibial bone, or internal bleeding within the leg.3
   Sciatic nerve. Neuropathy of the sciatic nerve may occur due to repeated injections in the hip, a complication of hip surgery, or trauma to the hip and/or pelvis.3
   Neuropathy of the common peroneal nerve occurs more frequently compared to other nerves in the leg.3 This nerve runs superficially near the knee, covered by skin and a thin layer of underlying tissue—making it vulnerable to direct injury
   What is Stork Manoeuvre?
   The patient is asked to stand on one leg, with arms folded across chest, and the
   eyes open. Absence of wobble or falling is said to exclude a significant disorder
   of balance or pyramidal lower limb weakness.
   What is Straight Thumb Sign?
   Median nerve lesions in the forearm cause weakness of flexor pollicis longus,
   which normally flexes the distal phalanx of the thumb. Hence the thumb remains
   straight when the patient attempts to grasp something or make a fist. The ‘pinch
   sign’ may also be present.
   What is Heterophoria?
   It is an eye condition in which the directions that the eyes are pointing at rest position, when not performing binocular fusion, are not the same as each other, or, “not straight”. This condition can be esophoria, where the eyes tend to cross inward in the absence of fusion; exophoria, in which they diverge; or hyperphoria, in which one eye points up or down relative to the other. Phorias are known as ‘latent squint’ because the tendency of the eyes to deviate is kept latent by fusion.
   What is Pseudo Babinski sign?
   One may encounter this type of response in sensitive individuals, plantar hyperaesthesia, and choreo-athetosis due to hyperkinesis.
   What is the Babinski sign?
   The Babinski sign may be a normal occurrence in the first year of life. In the infant, before myelination of the nervous system is complete and an upright stance has been achieved, the normal plantar response is extensor, due to a brisker ‘flexion synergy ‘as part of the withdrawal response to pain.
   What is Striatal Toe?
   Striatal toe refers to the spontaneous tonic extension of the hallux which is
   seen in dystonic syndromes, and as a feature of extrapyramidal disorders, such
   as dopa-responsive dystonia. Striatal toe may be confused with Babinski’s sign
   (extensor plantar response) and pseudo-Babinski’s sign (= ‘phasic striatal toe’),
   the principal difference being that both the latter are elicited by stimulation
   whereas the former is a tonic response.
   What is String Sign?
   The string sign has been advocated as a way of testing visual field integrity in
   patients whose cooperation cannot be easily gained, by asking them to point
   quickly to the centre of a piece of string held horizontally in the examiner’s hands.
   If visual fields are full, the patient will point to the approximate centre; if there
   is a left field defect, pointing will be to the right of centre, and vice versa for a
   right field defect. Altitudinal field defects may be similarly identified by holding
   the string vertically.
   What is Stupor?
   Stupor is a state of altered consciousness characterized by deep sleep or unresponsiveness, in which patients are susceptible to arousal only by vigorous and/or
   repeated stimuli, with lapse back into unresponsiveness when the stimulus stops.
   Stupor is a less severe impairment of conscious level than coma, but worse
   than obtundation (torpor). It is suggestive of diffuse cerebral dysfunction, e.g.
   drug-induced.
   What is Stutter?
   Stutter, one of the reiterative speech disorders, is usually a developmental problem, but may be acquired in aphasia with unilateral or bilateral hemisphere
   lesions (e.g. vascular damage, trauma, Alzheimer’s disease, Parkinson’s disease, progressive supranuclear palsy). Unlike developmental stutter, acquired
   stutter may be evident throughout sentences, rather than just at the beginning. Furthermore, developmental stutter tends to occur more with plosives
   (phonemes where the flow of air is temporarily blocked and suddenly released,
   as in ‘p’, ‘b’), whereas acquired stutter is said to affect all speech sounds fairly
   equally. Cessation of developmental stutter following bilateral thalamic infarction in adult life has been reported, as has onset of stutter after anterior corpus
   callosum infarct.
   What is Sucking Reflex?
   Contact of an object with the lips will evoke sucking movements in an infant.
   The reflex may re-emerge in dementia.
   What is Collier’s sign?
   It, (also known as Collier’s tucked lid sign or posterior fossa stare) is bilateral or unilateral eyelid retraction.. It is an accepted medical sign of a midbrain lesion, first described in 1927 by J Collier.
   What is Sundowning?
   ‘Sundowning’, or sundown syndrome, is increased confusion, agitation, or disorientation in the late afternoon, evening, and night-time, which may be seen
   in patients with delirium, and sometimes in dementia. In dementia, there may
   be complete reversal of sleep schedule with daytime somnolence and nocturnal
   wakefulness.
   Although this syndrome may relate to worsening of visual cues with increasing darkness, it may also occur in well-lit environments. A disorder of circadian
   rhythms is a possible physiological correlate of ‘sundowning’: EEG recordings in
   delirious patients may suggest this.
   Suggested management for dementia patients with sundowning includes use
   of structured activities at the relevant times (enforcement of external Zeitgebers)
   and increased staffing or availability of family members. Sedative medications are
   probably best avoided.
   What is Supranuclear Gaze Palsy?
   A supranuclear gaze palsy results from pathology located above the cranial
   nerve nuclei supplying the extraocular muscles. Voluntary gaze is impaired while
   the integrity of the oculomotor nuclei and infranuclear connections may be
   demonstrated by the preservation of:
   • Vestibulo-ocular reflexes (VOR): overcoming the ophthalmoplegia, at least
   in the early stages (e.g. the supranuclear gaze palsy in the vertical plane in
   progressive supranuclear palsy);
   • Oculocephalic reflex (doll’s head, doll’s eye manoeuvre);
   • Bell’s phenomenon.
   Supranuclear gaze palsies may be classified as follows:
   • Horizontal:
   Hemisphere (frontal) lesion: eyes deviated to the side of the lesion, or
   in the case of an irritative (e.g. epileptic) focus away from the side of
   the lesion.
   Paramedian pontine reticular formation: eyes deviated to contralateral
   side.
   • Vertical:
   Brainstem compression/distortion;
   Dorsal upper midbrain (e.g. rostral interstitial nucleus of the median
   longitudinal fasciculus; pineal lesion causing Parinaud’s syndrome);
   Skew deviation.
   Recognized causes of supranuclear gaze palsy include
   • Progressive supranuclear palsy (PSP; Steele–Richardson–Olszewski syndrome);
   • Creutzfeldt–Jakob disease;
   • Corticobasal degeneration;
   • Progressive subcortical gliosis of Neumann;
   • Adult-onset Niemann–Pick disease;
   • Gaucher’s disease.
   What are Conjugate gaze palsies?
   They are neurological disorders affecting the ability to move both eyes in the same direction. These palsies can affect gaze in a horizontal, upward, or downward direction.
   What is (VOR)?
   The vestibulo-ocular reflex (VOR) is a reflex, where activation of the vestibular system causes eye motion. This reflex functions to stabilize images on the retinas (in yoked vision) during head motion by producing eye motions in the instructions opposite to head movement, hence maintaining the image on the center of the visual field (s).
   What is Parinaud’s syndrome?
   Parinaud’s syndrome refers to the group of abnormalities of eye movement and pupil dysfunction. There is an inability to move the eyes up or down due to compression of the vertical gaze center at the rostral insterstitial nucleus of medial longitudinal fasciculus. Loss of blood supply resulting in damage to the mesencephalic tectum.
   What is Prévost sign?
   The Prévost sign, also known as the Vulpian sign, refers to conjugate ocular deviation in patients with acute cortical hemiparetic stroke. The direction is variable, depending on the location of the stroke 3. In a hemispheric stroke, the eyes usually deviate towards the lesion (away from the hemipares
   What is Surface Dyslexia?
   Surface dyslexia is a type of dyslexia, or reading disorder. According to Marshall & Newcombe’s (1973) and McCarthy & Warrington’s study (1990), patients with this kind of disorder cannot recognize a word as a whole due to the damage of the left parietal or temporal lobe. Individuals with surface dyslexia are unable to recognize a word as a whole word and retrieve its pronunciation from memory. Rather, individuals with surface dyslexia rely on pronunciation rules. Thus, patients with this particular type of reading disorder read non-words fluently, like “yatchet”, but struggle with words that defy pronunciation rules (i.e. exception words). For example, a patient with surface dyslexia can correctly read regular words like “mint”, but will err when presented a word that disobeys typical pronunciation rules, like “pint”. Often, semantic knowledge is preserved in individuals with surface dyslexia.
   What is Suspended Sensory Loss?
   Sensory loss or impairment involving the trunk and proximal limbs may be
   described as suspended, or in a ‘cape-like’, ‘bathing suit’, ‘vest-like’, or cuirasse
   distribution. This may reflect intrinsic or intramedullary spinal cord pathology,
   in which case other signs of myelopathy may be present, including dissociated
   sensory loss, but it can also occur in peripheral neuropathic disease such as acute
   porphyria.
   What is Swan Neck?
   This term has been applied to thinning of the neck musculature, as in myotonic
   dystrophy type 1,
   What is Swearing?
   Swearing is not, in sensu strictu, a part of language, serving merely to add force
   of emotion to the expression of ideas; hence it is within the same category as
   loudness of tone or violence of gesticulation.
   What is Sweat Level?
   A definable sweat level, below which sweating is absent, is an autonomic change
   which may be observed below a spinal compression.
   What is Swinging Flashlight Sign?
   The swinging flashlight sign or test, originally described by Levitan in 1959, compares the direct and consensual pupillary light reflexes in one eye; the speed of
   swing is found by trial and error. Normally the responses are equal but in the
   presence of an afferent conduction defect an inequality is manifest as pupillary
   dilatation. The test is known to be unreliable in the presence of bilateral afferent defects of light conduction. Subjective appreciation of light intensity, or light
   brightness comparison, is a subjective version of this test.
   What is Syllogomania?
   Syllogomania is excessive hoarding behaviour, often contributing to domestic
   squalor, as seen in Diogenes syndrome.
   What is Synaesthesia?
   Synaesthesia is a perceptual experience in one sensory modality following stimulation of another sensory modality. The most commonly encountered example
   is colour-word synaesthesia (‘coloured hearing’ or chromaesthesia), experiencing a visual colour sensation on hearing a particular word. Synaesthesia occurs
   in a small percentage of the normal population. Known synaesthetes include
   the composers Messiaen and Scriabin, the artist Kandinsky, and the author
   Nabokov. There may be concurrent excellent memory (hypermnesia), sometimes
   of a photographic nature (eidetic memory). Symptomatic synaesthesia is rare but
   has been described with epileptic seizures of temporal lobe origin and with drug
   use (LSD). Characteristics ascribed to synaesthetic experience include its involuntary or automatic nature, consistency, generic or categorical and affect-laden quality.
   Neuropsychologically, this phenomenon has been conceptualized as a break
   down of modularity. Functional imaging studies of colour-word synaesthetes
   show activation of visual associative areas of cortex (but not primary visual cortex), as well as perisylvian language areas, when listening to words which evoke
   the experience of colour.
   What is Synkinesia, Synkinesis?
   The term synkinesis may be used in different ways. It may refer to involuntary movements which accompany or are associated with certain voluntary
   movements (mitbewegungen, motor overflow). These may be physiological, for
   example, the swinging of the arms when walking. Alternatively, such associated
   phenomena may be pathological, e.g. the involuntary contraction of orbicularis
   oculi when opening the mouth (the Marin–Amat syndrome: inverse Marcus
   Gunn phenomenon), acquired after lower motor neurone facial (VII) nerve
   palsies and presumed to reflect aberrant reinnervation. Aberrant nerve regeneration is common to a number of synkinetic phenomena, such as elevation of a
   ptotic eyelid on swallowing (Ewart phenomenon) and upper eyelid elevation or
   retraction on attempted downgaze (pseudo-Von Graefe’s sign). Crocodile tears,
   or lacrimation when salivating, due to reinnervation following a lower motor
   neurone facial nerve palsy, may also fall under this rubric, although there is no
   movement per se (autonomic synkinesis), likewise gustatory sweating.
   Abnormal synkinesis may be useful in assessing whether weakness is organic
   or functional (cf. Hoover’s sign).
   Synkinesis may also refer to the aggravation of limb rigidity detected when
   performing movements in the opposite limb (e.g. clenching and relaxing the fist),
   also known as activated rigidity or Froment’s sign.
   What is Gustatory sweating?
   It is sweating on the forehead, face, scalp, and neck occurring soon after ingesting food. Some gustatory sweating is normal after eating hot, spicy foods. Otherwise, gustatory sweating is most commonly a result of damage to a nerve that goes to the parotid gland, the large salivary gland in the cheek.
   What is Jaw winking syndrome?
   Jaw winking is considered a trigemino-oculomotor synkinesis due to misdirection of proprioceptive impulses from the pterygoid muscles to the oculomotor nucleus, and occurs in 2-13% of patients with congenital ptosis.1 In inverse jaw winking, the lid closes on opening the mouth.
   What is Prayer sign”?
   The “Prayer sign” indicates the presence of diabetic cheiroarthropathy. It is characterized by patient inability to completely close gaps between opposed palms and fingers when pressing their hands together in prayer’s position.
   What is ‘Table Top’ Sign?
   The ‘table top’ sign describes the inability to place the hand flat on a level
   surface, recognized causes of which include ulnar neuropathy (main en griffe),
   Dupuytren’s contracture, diabetic cheiroarthropathy, and camptodactyly.
   What is Tachylalia?
   Tachylalia is increased speech velocity. This has been reported in patients with
   cerebrotendinous xanthomatosis, particularly in the 20–40-year age group.
   What is Tachyphemia?
   Tachyphemia is repetition of a word or phrase with increasing rapidity and
   decreasing volume; it may be encountered as a feature of the speech disorders
   in parkinsonian syndromes.
   What is Tactile Agnosia?
   Tactile agnosia is a selective impairment of object recognition by touch despite
   (relatively) preserved somaesthetic perception. This is a unilateral disorder resulting from lesions of the contralateral inferior parietal cortex. Braille alexia may
   be a form of tactile agnosia, either associative or apperceptive.
   What is Tadpole Pupils?
   Pupillary dilatation restricted to one segment may cause peaked elongation of the
   pupil, a shape likened to a tadpole’s pupil. This has been recorded in Horner’s
   syndrome, migraine, and Holmes–Adie pupil.
   What is sensory ataxia?
   Sensory ataxia is both a symptom and a sign in neurology. It is a form of ataxia (loss of coordination) caused not by cerebellar dysfunction but by loss of sensory input into the control of movement.
   What are symptoms of cerebellar ataxia?
   Cerebellar ataxia can lead to a number of symptoms, such as:
   a wide and unsteady gait when walking.
   poor hand-eye coordination.
   tremors.
   slow and imprecise speech.
   a lack of sensory capability.
   What are Cerebellar disorders?
   The main clinical features of cerebellar disorders include incoordination, imbalance, and troubles with stabilizing eye movements. There are two distinguishable cerebellar syndromes — midline and hemispheric. Midline cerebellar syndromes are characterized by imbalance.
   What is Tandem Walking?
   Tandem walking, or heel–toe walking, also known as the dynamic Romberg’s
   test, is the ability to walk along a straight line placing one foot directly in front
   of the other, heel to toe, which may be likened to walking a tightrope.
   In ataxic disorders, cerebellar (midline cerebellum, in which axial coordination is most affected) or sensory (loss of proprioception), the ability to tandem
   walk is impaired, as reflected by the tendency of such patients to compensate for
   their incoordination by developing a broad-based gait.
   What is Romberg testing?
   The Romberg Test is a neurological test which detects poor balance because of deficits in proprioception. The test involves standing with your feet together and closing your eyes.
   What is positive Romberg?
   During a Romberg’s test, a patient is asked to stand up with his or her feet parallel to each other. People suffering from multiple sclerosis may experience a positive Romberg’s test. A Romberg’s test can be used to help diagnose vertigo. A positive Romberg’s test may indicate disease in the posterior aspect of the spinal cord.
   Is the Romberg test better than the original Romberg test?
   Many believe that the sharpened Romberg test is a better indicator of vestibular impairment than the original Romberg test. The sharpened Romberg test results give an objective measure of postural stability.
   What is negative Romberg sign?
   When Romberg test is positive, it indicates ataxia due to dorsal column disease and impaired proprioception. Negative Romberg’s Test result: It is characterised by minimal swaying. A negative Romberg’s test indicates that the person does not have ataxia and the proprioception is normal.
   What is the usual reason for conducting the Romberg test?
   Romberg’s test is a physical exam maneuver done as part of a thorough neurologic exam. In the test, patients are asked to maintain a standing position while keeping their eyes closed. A positive test result, indicated by loss of stability or falling, can indicate disease in the posterior aspect of the spinal cord.
   Is Romberg a walking Romberg?
   The combination of either Hoffman’s reflex and/or walking Romberg was positive in 96% of patients. The walking Romberg sign is more useful than the traditional Romberg test as it shows evidence of a proprioceptive gait deficit in significantly more patients with cervical myelopathy than is found on conventional neurological examination.
   What is Rombergism?
   It is the tendency of a patient to sway while standing still with feet close together and eyes closed; associated with loss of position sense.
   What does Romberg sign mean?
   Romberg sign – a sign of sensory ataxia if a patient standing with heels touching cannot maintain balance on closing eyes. Synonym(s): rombergism; Romberg symptom (1); Romberg test; station test.
   What is the cause of Romberg s sign?
   This section shows a full list of all the diseases and conditions listed as a possible cause of Romberg’s sign in our database from various sources. Multiple sclerosis. Neurosyphilis — tabes dorsalis – positive Romberg’s sign. Peripheral nerve disease. Pernicious anaemia.
   What does a positive Romberg test mean?
   Romberg’s test is positive if the patient falls while the eyes are closed. Swaying is not a positive sign as it shows proprioceptive correction. Patients with a positive result are said to demonstrate Romberg’s sign or Rombergism.
   What is Tasikinesia?
   Tasikinesia is forced walking as a consequence of an inner feeling of restlessness
   or jitteriness as encountered in akathisia.
   What is Restless legs syndrome (RLS)?
   It is a condition that causes an uncontrollable urge to move your legs, usually because of an uncomfortable sensation. It typically happens in the evening or night-time hours when you’re sitting or lying down. Moving eases, the unpleasant feeling temporarily. Rest-less legs syndrome, now known as restless legs syndrome/Willis-Ekbom disease (RLS/WED), can begin at any age and generally worsens as you age. It can disrupt sleep, which interferes with daily activities. Simple…
   What is Tay-Sachs disease?
   In the most common form, an infant usually begins showing symptoms by about 6 months of age. Signs and symptoms of Tay-Sachs disease can include the following:
   Loss of motor skills, including turning over, crawling and sitting up
   Exaggerated reactions when the baby hears loud noises
   Seizures
   Vision and hearing loss
   “Cherry-red” spots in the eyes
   Muscle weakness
   Movement problems
   What is Tasikinesia? Teichopsia?
   Meaning literally ‘town-wall vision’, this term was coined by Airy in 1870 to
   describe the ‘bastioned form of transient hemiopsia’ which he experienced as
   part of his own migraine attacks, and illustrated in his paper.
   What does telegraphic speech mean?
   Telegraphic speech, according to linguistics and psychology, is speech during the two-word stage of language acquisition in children, which is laconic and efficient. The name derives from the fact that someone sending a telegram was generally charged by the word.
   What does agrammatism mean?
   It is a type of aphasia, usually caused by cerebral disease, characterized by an inability to construct a grammatical or intelligible sentence while retaining the ability to speak single words. Nearby words. Origin of agrammatism.
   What is Tasikinesia? Telopsia?
   Telopsia is a visual illusion in which the image is altered in position; the term may
   also be used to refer to the image appearing abnormally distant (cf. porropsia).
   What is Tasikinesia? Temporal Desaturation?
   Temporal desaturation refers to an impairment in perception of red targets confined to the temporal visual hemifield. This may be the earliest indication of
   a developing temporal field defect, as in a bitemporal hemianopia due to a
   chiasmal lesion, or a monocular temporal field defect (junctional scotoma of
   Traquair) due to a distal ipsilateral optic nerve lesion.
   What is Temporal Pallor?
   Pallor of the temporal portion of the optic nerve head may follow atrophy of the
   macular fibre bundle in the retina, since the macular fibres for central vision enter
   the temporal nerve heads. This may be associated with impairment of central
   vision.
   What is Optic Atrophy (Optic Neuropathy)?
   Optic atrophy is an ophthalmic condition that affects the optic nerve, which is responsible for carrying impulses from the eyes to the brain. The term “atrophy” indicates the process of deterioration or wasting away. Death and/or damage of the optic nerve cells or optic neurons that are located anywhere between lateral geniculate body and retinal ganglion cells leads to the development of symptoms associated with this condition.
   Optic atrophy cannot be classified as a disease; rather it is a symptom of a possibly more serious condition. It can be caused by various forms of pathologies and might ultimately lead to severe vision problems and blindness. Optic atrophy is also referred to as Optic neuropathy.
   What are the causes of optic atrophy?
   A number of factors can lead to optic atrophy. These include:
   OPTIC NEURITIS
   It is characterized by inflammations of optic nerve and is associated with the swelling and damage of the myelin sheath that covers the optic nerve. The symptoms of this condition include:
   Sensations of pain felt during eye movement
   A sudden or abrupt loss of vision
   Reduced colour vision capabilities (especially reds and shades of red)
   If the signs of Optic neuritis are observed on an MRI, alongside the presence of multiple demyelinating brain (white matter) lesions, multiple sclerosis might be present. A medical exam of optic nerve using an ophthalmoscope might show a swollen nerve; alternatively, it might also appear normal. The presence of reduced colour vision, visual field loss and afferent pupillary defect suggest optic neuritis. Although a patient might recover within 10 weeks, he or she may also suffer from permanent axonal loss and/or thinning of fiber layer of the retinal nerve.
   ISCHEMIC OPTIC NEUROPATHY
   These are caused by insufficient flow of blood or ischemia to the optic nerve. Blood is supplied to the anterior optic nerve by short posterior ciliary artery as well as choroidal circulation. A pial plexus originating from anterior communicating arteries, the ophthalmic artery, the anterior cerebral artery as well as the internal carotid artery supply blood intraorbitally to retrobulbar optic nerve. Ischemic optic neuropathies can be classified on the basis of the location of damage as well as the factor responsible for reduced blood flow.
   ANTERIOR ISCHEMIC OPTIC NEUROPATHY
   Anterior ischemic optic neuropathy or AION involves diseases that negatively affect optic nerve head as well as cause swelling of optic disc. These conditions frequently cause rapid and sudden visual loss in one eye. Inflammatory disorders of blood vessels, such as polyarteritis nodosa, giant cell arteritis, Wegener’s granulomatosis, Churg-Strauss syndrome, as well as rheumatoid arthritis can lead to arteritic AIONs or AAION. Most AION cases are non-arteritic AIONs or NAIONs. NAION is often experienced as pain-free loss of vision that mostly occurs after awakening and may last for several hours or even days. Most patients complain of losing the lower half of the visual field or inferior altitudinal loss, although superior altitudinal loss can also be seen. The pathophysiology of non-arteritic anterior ischemic optic neuropathy is not known, but is related to impoverished circulation in optic nerve head. NAIONs are frequently associated with elevated intraocular pressure caused by factors such as acute glaucoma and eye surgery, hypercoagulable states, diabetes mellitus, high cholesterol, a drop in one’s blood pressure due to eye surgery or acute glaucoma (glaucomatous optic neuropathy) and sleep apnea. Erectile dysfunction drugs, interferon-alpha and amiodarone have also been associated with NAIONs in some rare instances.
   POSTERIOR ISCHEMIC OPTIC NEUROPATHY
   It occurs when a patient experiences sudden visual loss without any signs of initial disc swelling that occurs with subsequent progression of optic atrophy. Posterior ischemic optic neuropathy can occur in individuals predisposed to NAION and AAION as well as in people spinal or cardiac surgery or serious hypotension episodes.
   Radiation optic neuropathy or RON is believed to be caused by ischemic factors and occurs anywhere between three months to eight or more years after the brain and its orbit have been exposed to radiation therapy. It can cause radiation retinopathy or damage of the retina, which leads to severe vision loss, and is believed to occur as a result of damage to the dividing glial and the vascular endothelial cells. Interferon treatment for Hepatitis C virus can also cause optic neuropathy.
   TRAUMATIC OPTIC NEUROPATHY
   Direct or indirect injuries can cause damage of the optic nerve. A head trauma can disrupt the anatomy and functions of optic nerve, especially if the intracanalicular area of the nerve is affected. Motorcycle accidents or falls can lead to loss of consciousness that is linked with multi-system trauma as well as serious brain injury. In some rare instances, an orbital hemorrhage following an injection behind eye can cause trauma to optic nerve. However, it can be managed quickly if it does not involve a direct optic nerve wound and is detected early. In patients having an orbital fracture, nose blowing or vomiting can inject air into orbit which can lead to damage of optic nerve.
   INFILTRATIVE OPTIC NEUROPATHY
   Various problems, such as inflammations, infections and tumors might infiltrate the optic nerve. The tumors can be both primary (cavernous hemangiomas, capillary hemangiomas and optic gliomas) and secondary (lymphoma, leukaemia, nasopharyngeal carcinoma and metastatic carcinoma). Sarcoidosis is the most common type of inflammatory disorder that affects the optic nerve. Opportunistic microbes, like viruses, bacteria or fungi can also infiltrate optic nerve.
   COMPRESSIVE OPTIC NEUROPATHY
   Infections, tumors or inflammatory processes might cause lesions to develop within the orbit and the optic canal. The lesions might cause the optic nerve to compress, which can lead to swelling of the optic disc along with progressive visual loss. The various orbital disorders include:

Meningiomas
Optic gliomas
Lymphangiomas
Hemangiomas
Dermoid cysts
Lymphomas
Carcinomas
Inflammatory orbital pseudotumor
Multiple myeloma
Thyroid ophthalmopathy
Patients may exhibit proptosis (bulging of the eye) and with mild colour deficiencies and near-normal vision with swelling of the disc.
MITOCHONDRIAL OPTIC NEUROPATHIES
Mitochondria plays an essential role in managing the operations of the retinal ganglion cells due to their high energy requirements. Various factors, such as vitamin depletion, genetic mutations, tobacco and/or alcohol abuse or drug abuse, can hamper efficient transportation of mitochondria that might lead to primary or secondary form of optic atrophy.
TOXIC OPTIC NEUROPATHIES
Toxic optic neuropathies might occur from intoxication from substances such as methanol, ethylene glycol, ethambutol, amiodarone or tobacco.
NUTRITIONAL OPTIC NEUROPATHIES
An undernourished individual suffering from low protein and vitamin levels may develop optic atrophy. Vitamin B12 deficiency might occur due to a gastric bypass surgery. Patients may experience disturbed colour vision and vision loss, although blindness is rare.
HEREDITARY OPTIC NEUROPATHIES
Hereditary optic neuropathies normally manifest as bilateral, symmetric central vision loss. Damage of the optic nerve is progressive and permanent in most cases of hereditary optic neuropathies. Some of these neuropathies include Leber’s hereditary optic neuropathy or LHON, Dominant optic atrophy and Behr’s syndrome.
What is Terson Syndrome?
Terson’s syndrome refers to vitreous haemorrhage in association with any form
of intracranial or subarachnoid haemorrhage.
Is there any difference between tetanus and tetany?
Tetany refers to muscular spasms which are usually intermittent in nature. On the other hand, Tetanus is an infectious disease affecting the central nervous system. Accordingly, tetany is a disease manifestation whereas tetanus is a disease condition that can cause tetany. Thus, this is the principal difference between tetany and tetanus.
What is Risus sardonicus?
Risus sardonicus or rictus grin is a highly characteristic, abnormal, sustained spasm of the facial muscles that appears to produce grinning. Risus sardonicus may be caused by tetanus, strychnine poisoning, or Wilson’s disease, and has been reported after judicial hanging. The condition’s name, associated with the Mediterranean island of Sardinia, derives from the appearance of raised eyebrows and an open “grin” – which can appear sardonic or malevolent to the lay observer – displayed by those experiencing these muscle spasms.
What does tetra paresis mean?
Tetra paresis, or quadriparesis, is a condition in which all four limbs are weak. Several causes exist, many of which are treatable. In some patients with tetra paresis, the limbs may lack voluntary motor control, while in other patients, some limbs or parts of limbs may be paralyzed but others function normally. Paraparesis generally results from spinal cord lesions caudad to the second thoracic spinal cord segment, whereas tetraparesis occurs because of lesions cranial to this segment
What is the difference between quadriparesis and quadriplegia?
Quadriparesis vs. quadriplegia. Quadriparesis and quadriplegia are both conditions characterized by loss of function in all four limbs. The main difference is in how much function is lost. A person with quadriparesis experiences weakness and a partial loss of function of the limbs.
How is quadriplegia treated?
Treatment of Quadriplegia or Tetraplegia 1 If the cause is bruising or swelling of the spinal cord, the nerves may start functioning again. Steroids are given to prevent and reduce any swelling of the spinal cord. 2 If the cause is an injury, then emergent treatment is required so that further damage to the spine is prevented. 3 There is no treatment which can reverse this condition. Surgery can only help so much and when done immediately after the injury, it can help in supporting and stabilizing the patient.
What is Tic?
A tic is an abrupt, jerky repetitive movement involving discrete muscle groups,
hence a less complex movement than a stereotypy. Vocal (phonic) tics are also
described. Tics vary in intensity, lack rhythmicity, and are relatively easy to imitate. They may temporarily be voluntarily suppressed by will power (perhaps
accounting for their previous designation as ‘habit spasms’) but this is usually
accompanied by a growing inner tension or restlessness, only relieved by the
performance of the movement.
The pathophysiology of tics is uncertain. The belief that Tourette syndrome
was a disorder of the basal ganglia has now been superseded by evidence of
dysfunction within the cingulate and orbitofrontal cortex, perhaps related to
excessive endorphin release. The aetiological differential diagnosis of tic includes
• Idiopathic;
• Tourette syndrome;
• Tics related to structural brain damage;
• Drug-induced tics;
• Tics triggered by streptococcal infection.
Treatment of tics is most usually with dopamine antagonists (haloperidol, Sulpiride) and opioid antagonists (naltrexone); clonidine (central α2 adrenergic receptor antagonist) and tetrabenazine (dopamine-depleting agent) have also been reported to be beneficial on occasion. Botulinum toxin injections and deep brain stimulation have also been tried.
The word tic has also been used to describe the paroxysmal, lancinating pains of trigeminal neuralgia (tic douloureux).
What is the definition of stereotypy?
A stereotypy is a repetitive or ritualistic movement, posture, or utterance. Stereotypies may be simple movements such as body rocking, or complex, such as self-caressing, crossing and uncrossing of legs, and marching in place.
What is Klazomania?
Klazomania (to scream) refers to compulsive shouting; it has features resembling the complex tics such as echolalia, palilalia and coprolalia seen in tic disorders, but has been seen in people with encephalitis lethargica, alcohol abuse and carbon monoxide poisoning. It was first reported by L. Benedek in 1925 in a patient with postencephalitic parkinsonism. Little is known about the condition, and few cases have been reported.
What is Tic Convulsif?
Tic convulsif is a name that has been given to the combination of trigeminal
neuralgia (tic douloureux) with hemifacial spasm. Both may be characterized
as neurovascular compression syndromes.
What is Visual disorientation syndrome?
It is a loss of the ability to comprehend the meaning or recognize the importance of various forms of stimulation that cannot be attributed to impairment of a primary sensory modality.
What is the absence bow tie sign?
Absent bow tie sign (knee) The absent bow tie sign represents the loss of the normal appearance of the menisci on parasagittal MRI images and is suggestive of meniscal injury. Normally the medial and lateral menisci appear as low signal bow-tie-shaped structures between the femoral condyles and tibial plateaux.
What is Tilted Disc?
Tilted optic disc is a benign anomaly, causing the discs (it is usually bilateral) to
look oval or lopsided, with a bitemporal superior visual field defect which does
not respect the vertical midline.
What is Tinel’s Sign (Hoffmann–Tinel Sign)?
Tinel’s sign (Hoffmann–Tinel sign) is present when tingling (paraesthesia) is
experienced when tapping lightly with a finger or a tendon hammer over a
compressed or regenerating peripheral nerve. The tingling (Tinel’s ‘sign of formication’) is present in the cutaneous distribution of the damaged nerve (‘peripheral
reference’). Although originally described in the context of peripheral nerve
regeneration after injury, Tinel’s sign may also be helpful in diagnosing focal
entrapment neuropathy such as carpal tunnel syndrome. However, it is a ‘soft’
sign; like other provocative tests for carpal tunnel syndrome (e.g. Phalen’s sign) it
is not as reliable for diagnostic purposes as electromyography (EMG). Its specificity has been reported to range between 23 and 60% and sensitivity between 64 and 87%.
A ‘motor Tinel sign’ has been described, consisting of motor EMG activity and jerking of muscles evoked by manipulation of an entrapped nerve trunk.
The neurophysiological basis of Tinel’s sign is presumed to be the lower
threshold of regenerating or injured (demyelinated) nerves to mechanical stimuli, which permits ectopic generation of orthodromic action potentials, as in Lhermitte’s sign.
What is Cubital tunnel syndrome (CBTS)?
It is a peripheral nerve compression syndrome. It is an irritation or injury of the ulnar nerve in the cubital tunnel at the elbow. This is also termed ulnar nerve entrapment and is the second most common compression neuropathy in the upper extremity after carpal tunnel syndrome. It represents a source of considerable discomfort and disability for the patient and may, in extreme, cases lead to a loss of function of the hand. Cubital tunnel syndrome is also often misdiagnosed.
Peripheral nerve compression syndromes are characterised by chronic irritation and pressure lesions on the sites where nerves have to pass through narrow anatomic spaces and fibro-osseous structures. The main clinical manifestation of this type of compression are paresthesia, sensory impairment and paresis.
Cubital tunnel syndrome can also be caused by traction, pressure or ischemia of the ulnar nerve which passes through the cubital tunnel at the medial side of the elbow.[5] Pain or paraesthesia in the fourth and fifth finger and pain in the medial aspect of the elbow, which may extend proximally or distally, is caused by compression of the ulnar nerve. There is only limited evidence that proves the effectiveness of nonsurgical and surgical interventions to treat cubital tunnel syndrome.
What is Wartenberg sign?
It is (abduction of the fifth digit due to weakness of the third palmar interosseous muscle) may be present.
What is the posterior pelvic pain provocation test?
It is a pain provocation test used to determine the presence of sacroiliac dysfunction. It is used (often in pregnant women) to distinguish between pelvic girdle pain and low back pain. The test is also known as: PPPP test, P4 test, Thigh thrust test, Posterior shear test, POSH test
Technique
With the patient supine, the hip is flexed to 90° (with bended knee) to stretch the posterior structures. By applying axial pressure along the length of the femur, the femur is used as a lever to push the ilium posteriorly. One hand is placed beneath the sacrum to fixate its position while the other hand is used to apply a downward force to the femur. Broadhurst and Bond suggest to add hip adduction towards the midline while Laslett & Williams advise to avoid excessive adduction due to discomfort for the patient.
The test is positive for pelvic girdle pain if the axial pressure provokes pain over the sacroiliac joint that is familiar to the patient.
What is Tinnitus?
Tinnitus is the perception of elementary non-environmental sound or noise in the
ear. This is most usually a subjective phenomenon (i.e. heard only by the sufferer),
occurring in the absence of acoustic stimulation. It may occur in conjunction
with either conductive or sensorineural hearing loss. However, in about one-fifth
of sufferers, tinnitus is objective (i.e. heard also by an observer). This may result
from:
• vascular causes: e.g. arteriovenous malformation, fistula; carotid or vertebrobasilar bruit;
• mechanical causes: e.g. palatal myoclonus (ear click).
The common causes of subjective tinnitus are as follows:
• middle/inner ear disease: cochlear hydrops (Ménière’s disease), presbycusis,
acoustic tumour;
• pulsatile: normal heartbeat, glomus jugulare tumour, raised intracranial
pressure, cervical/intracranial aneurysm, arteriovenous malformation.
What is ‘Tip-of-the-Tongue’ Phenomenon?
The “tip of the tongue” (TOT) phenomenon is a state in which one cannot quite recall a familiar word but can recall words of similar form and meaning.
What does circumlocution mean?
Circumlocution definition, a roundabout or indirect way of speaking; the use of more words than necessary to express an idea.
What is Todd’s Paralysis, Todd’s Paresis?
Todd’s paralysis (Todd’s paresis) is a transient localized weakness (usually hemiparesis), lasting seconds to minutes (exceptionally 24–48 h), observed following
a focal motor epileptic seizure or Jacksonian seizure originating in the central
motor strip, or febrile convulsion, a phenomenon first described by RB Todd
in 1854. The pattern and duration of postictal signs are quite heterogeneous.
Aphasia is also described. A postictal ‘paralytic’ conjugate ocular deviation may
be observed after adversive seizures. Todd’s paresis is of localizing value, being
contralateral to the epileptogenic hemisphere.
The differential diagnosis of transient postictal hemiparesis includes stroke,
hemiplegic migraine, and, in children, alternating hemiplegia.
Toe Walking
Toe walking, or cock walking, is walking on the balls of the toes, with the heel
off the floor. A tendency to walk on the toes may be a feature of hereditary
spastic paraplegia and the presenting feature of idiopathic torsion dystonia in
childhood.
What is Tongue Biting?
Tongue biting is one feature of a seizure: in a generalized tonic–clonic epileptic
seizure the side or sides of the tongue are typically bitten: a specific but not very
sensitive sign. In a non-epileptic seizure, the tip of the tongue may be more likely
to be bitten.
What is Tonic Spasms?
Painful tonic spasms occur in multiple sclerosis, especially with lesions of the posterior limb of the internal capsule or cerebral peduncle, perhaps due to ephaptic
activation, or following putaminal infarction.
What is Obtundation?
Obtundation refers to less than full alertness (altered level of consciousness), typically as a result of a medical condition or trauma.
What is Torticollis?
Torticollis (wryneck, cervical dystonia, nuchal dystonia, spasmodic torticollis) is
a movement disorder characterized by involuntary contraction of neck musculature, involving especially sternocleidomastoid, trapezius, and splenius capitis. In
the majority of cases (>50%) this produces head rotation, but laterocollis, retrocollis, tremulous (‘no–no’) and complex (i.e. variable) forms are seen; antecollis is
unusual. Contractions are usually unilateral, may be associated with local pain,
and, as with other types of dystonia, may be relieved by a ‘sensory trick’ (geste
antagoniste). Causes of torticollis include
• Idiopathic (the majority);
• Secondary to acquired cervical spine abnormalities, trauma;
• Cervical spinal tumour;
• Tardive effect of neuroleptics.
The treatment of choice is botulinum toxin injections into the affected muscles. Injections benefit up to 70–80% of patients, but need to be repeated every 3 months or so.
What is tortopia?
The term tortopia comes from the Latin tor-tum (that which has been turned) and the Greek verb opsis (seeing). It translates loosely as ‘seeing things in a tilted position’. The term was proposed in 1983 by the American neurologist Allan H. Ropper to denote a symptom complex characterized by a tilting of the visual environment.
What is geste antagoniste?
The geste antagoniste (moving an arm to the face or head) is a well-known clinical feature in cervical dystonia (CD) to alleviate the abnormal posture. The clinical phenomenology of these manoeuvres has not so far been assessed systematically.
What is Tourette syndrome?
It (TS or simply Tourette’s) is a common neurodevelopmental disorder with onset in childhood, characterized by multiple motor tics and at least one vocal (phonic) tic. These tics characteristically wax and wane, can be suppressed temporarily, and are typically preceded by an unwanted urge or sensation in the affected muscles.
What is Transcortical Aphasias?
Transcortical aphasias may be categorized as either motor or sensory.
• Transcortical motor aphasia (TCMA):
TCMA is associated with pathology (usually infarction) in the supplementary motor area, superior to Broca’s area (left lateral frontal cortex) or in subcortical structures including white matter projections and dorsal caudate nucleus; it has clinical similarities with Broca’s aphasia.
• Transcortical sensory aphasia (TCSA):
There is a dissociation between preserved repetition (cf. conduction
aphasia) and impairments of spoken and written language comprehension without phonemic paraphasia. TCSA is associated with pathology (usually infarction) in the ventral and ventrolateral temporal lobe involving the fusiform gyrus and the inferior temporal gyrus, and posterior convexity lesions involving the posterior middle temporal gyrus and the temporooccipital junction. It has similarities with Wernicke’s aphasia.
Dynamic aphasia may be a lesser version of TCMA, in which there are no
paraphasias and minimal anomia, preserved repetition, and automatic speech,
but reduced spontaneous speech. This may be associated with lesions of dorsolateral prefrontal cortex (‘frontal aphasia’) in the context of frontal lobe degeneration. There may be incorporational echolalia, when the patient uses the examiner’s question to help form an answer.
What is Broca’s aphasia?
It is a type of aphasia characterized by a lack of fluency of speech, usually with preserved language comprehension. Aphasia, the loss of language ability, results from a language problem acquired after normal language was already established.
What is Conduction aphasia/ Associative aphasia?
It is also called associative aphasia, is an uncommon form of difficulty in speaking (aphasia). It is caused by damage to the parietal lobe of the brain. An acquired language disorder, it is characterised by intact auditory comprehension, coherent (yet paraphasic) speech production, but poor speech repetition.
What is Dynamic aphasia?
A language-based syndrome characterized by marked reduction in spontaneous propositional speech despite preserved naming, comprehension, and the ability to produce speech was first characterized by Lichtheim in 1885 and termed dynamic aphasia; Luria subsequently classified dynamic aphasia as a subtype of transcortical motor aphasia.
What does echolalia mean?
The person with echolalia may repeat noises, phrases, or words. Echolalia is a symptom of brain damage or psychiatric disorders, and the person with echolalia may or may not be able to communicate normally or understand others. Children with autism and developmental disorders, as well as very young children, may exhibit echolalia.
What is the meaning of paraphasia?
The habitual substitution of inappropriate or meaningless words or jargonisms. Paraphasias. • Literal paraphasia—Substitution of an inappropriate phoneme (syllable). • Verbal paraphasia—Substituion of a complete word; fluent paraphasic speech is termed jargon aphasia. • Delirium (incoherency).
What does Wernicke’s aphasia result in?
Wernicke’s aphasia causes difficulty speaking in coherent sentences or understanding others’ speech. Wernicke’s aphasia is the most common type of fluent aphasia. It occurs when the left middle side of the brain becomes damaged or altered. This part of the brain is known as Wernicke’s area, named after Carl Wernicke, a neurologist.
What are the hallmarks of a Wernicke s aphasia?
The hallmarks of a Wernicke’s aphasia are poor auditory processing, fluent speech, and poor repetition. Poor auditory processing means that the person with this type of aphasia may have difficulty understanding what you are saying to him.
What is transverse smile?
The three main features of the transverse characteristics of the smile are arch form, buccal corridor width and transverse can of the maxillary occlusal plane. The buccal corridor width is the negative space between the buccal surface of the maxillary first premolar and the inner point at which the lips join when the patient smiles.
What is myasthenic snarl?
A “myasthenic snarl” may be observed when the patient attempts to smile. The snarl follows contraction of the middle portion of the upper lip while the upper mouth corners fail to contract. On examination, many patients exhibit weak forced eye closure that can easily be overcome by the examiner
What is Tremblement Affirmatif?
The tremor may be a vertical nodding (tremblement affirmatif) or a horizontal movement (tremblement negatif). The head tremor, if involving a rotatory movement, may result in a sustained displacement of the head. Patients may also describe an intermittent head tremor occurring during periods of stress
What are Physiological tremor?
Physiological tremor increases in amplitude with anxiety, stress, fatigue, metabolic disorders (for example, cases of hyperadererergic state of alcohol, drug, or thyrotoxicosis), in response to the receipt of a number of medications (e.g., caffeine, other phosphodiesterase inhibitors, beta-adrenergic receptor agonists, glucoticodes).
What is Tremor?
Tremor is an involuntary movement, roughly rhythmic and sinusoidal, although
some tremors (e.g. dystonic) are irregular in amplitude and periodicity. Tremors
may be classified clinically:
• Rest tremor:
present when a limb is supported against gravity and there is no voluntary muscle activation, e.g. the 3.5–7 Hz ‘pill rolling’ hand tremor of
Parkinson’s disease; midbrain/rubral tremor.
• Action tremor:
present during any voluntary muscle contraction.
Various subtypes of action tremor are recognized:
• Postural tremor:
present during voluntary maintenance of a posture opposed by gravity,
e.g. arm tremor of essential tremor; 6 Hz postural tremor sometimes
seen in Parkinson’s disease (‘re-emergent tremor’), which may predate
emergence of akinesia/rigidity/rest tremor; modest postural tremor
of cerebellar disease; some drug-induced tremors (including alcohol withdrawal, delirium tremens); tremor of IgM paraproteinaemic neuropathy; wing-beating tremor of Wilson’s disease.
• Kinetic tremor:
present with movement, often with an exacerbation at the end of a
goal-directed movement (intention tremor), e.g. cerebellar/midbrain
tremor (3–5 Hz).
• Task-specific tremor:
evident only during the performance of a highly skilled activity, e.g.
primary writing tremor.
• Isometric tremor:
present when voluntary muscle contraction is opposed by a stationary
object, e.g. primary orthostatic tremor (14–18 Hz).
• Psychogenic tremors:
these are difficult to classify, with changing characteristics; the frequency with which such tremors are observed varies greatly between
different clinics; the coactivation sign (increase in tremor amplitude
with peripheral loading) is said to be typical of psychogenic tremor.
EMG may be useful for determining tremor frequency, but is only diagnostic
in primary orthostatic tremor.
Various treatments are available for tremor, with variable efficacy. Essential
tremor often responds to alcohol, and this is a reasonable treatment (previous anxieties that such a recommendation would lead to alcoholism seem
unjustified); alternatives include propranolol, topiramate, primidone, alprazolam, flunarizine, and nicardipine. In Parkinson’s disease, tremor is less reliably
responsive to levodopa preparations than akinesia and rigidity; anticholinergics
such as benzhexol may be more helpful (but may cause confusion). Primary
orthostatic tremor has been reported to respond to gabapentin, clonazepam,
primidone, and levodopa. Cerebellar tremor is often treated with isoniazid, but
seldom with marked benefit, likewise carbamazepine, clonazepam, ondansetron,
limb weights; stereotactic surgery may be an option in some patients disabled
with tremor.
What is Asterixis?
Asterixis is a tremor of the hand when the wrist is extended, sometimes said to resemble a bird flapping its wings. This motor disorder is characterized by an inability to maintain a position, which is demonstrated by jerking movements of the outstretched hands when bent upward at the wrist.
What are the risk factors of asterixis?
Asterixis risk factors are 1 Stroke. A stroke occurs when blood flow to a part of the brain is restricted. … 2 Liver disease. Liver diseases that put you at high risk of asterixis include cirrhosis or hepatitis. Both these conditions can cause scarring of the liver. 3 Kidney failure. Like the liver, the kidneys also remove toxic materials from the blood. … 4 Wilson’s disease. In Wilson’s disease, the liver doesn’t adequately process the mineral copper. If left untreated and allowed to build up, copper can damage the brain
What is head tremors?
The medical term for a trembling head is called tremor. Tremor is an unconscious, prosaic, shaking movement of one or more parts of the body, usually the hands, lower arms, face, vocal cords, trunk, legs and head. An essential tremor is a progressive neurological disorder of the hands, head and voice.
What is Knee tremor?
Among the common causes of leg tremors are diseases that affect the central nervous system, such as Parkinson’s disease. In some cases, a person may cause damage to his nerves that leads trembling. For example, a heavy drinker may suffer nerve damage that causes him to experience tremors.
What is Palatal myoclonus?
Palatal myoclonus causes involuntary, rhythmic movements of the soft palate and pharynx. The palate may bounce up and down, or twitch rhythmically to one side . Sometimes the larynx, eye muscles, diaphragm, and occasionally other muscles are also involved. The movements persist in sleep.
Does Palatal myoclonus occur in acute stroke?
Palatal myoclonus does not appear in the acute stage of stroke, but develops several months later. Occasionally, rhythmic, jerky movements are also observed in the face, eyeballs, tongue, jaw, vocal cord or extremities (mostly hands); they may not be synchronous with palatal movements.
What is essential palatal tremor?
Essential palatal tremor (EPT) is an uncommon disorder, distinct from symptomatic palatal tremor (SPT), but characterized by superficially similar rhythmic movements of the soft palate.
Can tremor cause voice tremors?
In cases of mild tremor, there may only be minor quavering in the voice. More severe tremor can actually cause interruptions in sound production. Variations in loudness (and sometimes in pitch) caused by essential voice tremor are rhythmic and always present, no matter the type of vocalization.
What is Tremor of the voice?
Tremor of the voice can be caused when any of the structures in the speech system is affected. Essential tremor of the voice may be caused by tremor in the soft palate, tongue, pharynx, or even muscles of respiration.
What is Holmes tremor?
Holmes tremor (also known as rubral, thalamic or midbrain tremor) is a rare kind of hyperkinetic movement disorder, clinically characterized by irregular, monolateral, high-amplitude jerks, sharing a quite similar frequency with those observed in Parkinson’s disease, usually less than 4.5 Hz; it is present at rest. It is a course, irregular tremor that is most prominent when the limbs are held outstretched, reminiscent of a bird’s flapping its wings; due to up and down excursion of arm at abducted shoulder. Seen mainly with Wilson disease.
Is Holmes tremor genetic?
Because brainstem stroke and lesions are typically the causes of Holmes tremor, there is little research supporting a genetic factor to the disease. However, one could be more susceptible to developing Holmes tremor if there is a familial history of stroke, substance abuse, or other disorders that increase risk.
What is Trendelenburg’s Sign?
Trendelenburg’s sign is tilting of the pelvis towards the side of the unaffected raised leg in a unilateral superior gluteal nerve lesion.
What is Triparesis?
It is a medical condition, similar to triplegia, but the major difference between the two is primarily that triplegia is total loss of function in three limbs, and triparesis denotes weakening of three limbs. Causes may be Medial medullary infarction, factitious disorder.
What is sequential paresis?
Bilateral facial paralysis is a rare condition and therefore represents a diagnostic challenge. We report the case of a 34-year-old healthy woman with sequential bilateral facial paralysis as a sole manifestation of sarcoidosis. She initially presented with an isolated left sided Bell’s palsy without any symptoms to suggest alternative diagnoses.
What is Triplopia?
Triplopia is seeing triple, a rare complaint, which may be due to oculomotor
nerve palsy, internuclear ophthalmoplegia, and abducens nerve palsy. It may
result from an unusual interpretation of abnormal eye movements
What are types of palsy?
Specific kinds of palsy include:
Bell’s palsy, partial facial paralysis
Bulbar palsy, impairment of cranial nerves
Cerebral palsy, a neural disorder caused by intracranial lesions
Conjugate gaze palsy, a disorder affecting the ability to move the eyes
Erb’s palsy, also known as brachial palsy, involving paralysis of an arm
Spinal muscular atrophy, also known as wasting palsy
Progressive supranuclear palsy, a degenerative disease
Squatter’s palsy, a common name for bilateral peroneal nerve palsy that may be triggered by sustained squatting.
Third nerve palsy, involving cranial nerve III
What is Third cranial nerve palsy?
Third cranial nerve disorders can impair ocular motility, pupillary function, or both. Symptoms and signs include diplopia, ptosis, and paresis of eye adduction and of upward and downward gaze. If the pupil is affected, it is dilated, and light reflexes are impaired. If the pupil is affected or patients are increasingly unresponsive, neuroimaging is done as soon as possible.
Third cranial (oculomotor) nerve disorders that cause palsies and affect the pupil commonly result from
Aneurysms (especially of the posterior communicating artery)
Trans tentorial brain herniation
Less commonly, meningitis affecting the brain stem (eg, TB meningitis)
The most common cause of palsies that spare the pupil, particularly partial palsies, is
Ischemia of the 3rd cranial nerve (usually due to diabetes or hypertension) or of the midbrain
Occasionally, a posterior communicating artery aneurysm causes oculomotor palsy and spares the pupil.
Diplopia and ptosis (drooping of the upper eyelid) occur. The affected eye may deviate slightly out and down in straight-ahead gaze; adduction is slow and may not proceed past the midline. Upward gaze is impaired. When downward gaze is attempted, the superior oblique muscle causes the eye to adduct slightly and rotate.
The pupil may be normal or dilated; its response to direct and to consensual light may be sluggish or absent (efferent defect). Mydriasis (pupil dilation) may be an early sign.
Diagnosis
Clinical evaluation
CT or MRI
What is Differential diagnosis of Third cranial nerve palsy?
Midbrain lesions that disrupt the oculomotor fascicle (Claude syndrome, Benedict syndrome)
Leptomeningeal tumour or infection
Cavernous sinus disease (giant carotid aneurysm, fistula, or thrombosis)
Intraorbital structural lesions (eg, orbital mucormycosis) that restrict ocular motility
Ocular myopathies (eg, due to hyperthyroidism or mitochondrial disorders)
Disorders of the neuromuscular junction (eg, due to myasthenia gravis or botulism)
Differentiation may be clinical. Exophthalmos or enophthalmos, a history of severe orbital trauma, or an obviously inflamed orbit suggests an intraorbital structural disorder. Graves orbitopathy (ophthalmopathy) should be considered in patients with bilateral ocular paresis, paresis of upward gaze or abduction, exophthalmos, lid retraction, lid lag during downward gaze (Graefe sign), and a normal pupil.
CT or MRI is required. If a patient has a dilated pupil and a sudden, severe headache (suggesting ruptured aneurysm) or is increasingly unresponsive (suggesting herniation), CT is done immediately. If ruptured aneurysm is suspected and CT (or MRI) does not show blood or is not available rapidly, other tests, such as lumbar puncture, magnetic resonance angiography, CT angiography, or cerebral angiography, are indicated. Cavernous sinus disease and orbital mucormycosis require immediate MRI imaging for timely treatment.
What is Sixth nerve palsy, or abducens nerve palsy?
Sixth nerve palsy, or abducens nerve palsy, is a disorder associated with dysfunction of cranial nerve VI (the abducens nerve), which is responsible for causing contraction of the lateral rectus muscle to abduct (i.e., turn out) the eye.[1] The inability of an eye to turn outward and results in a convergent strabismus or esotropia of which the primary symptom is diplopia (commonly known as double vision) in which the two images appear side-by-side. Thus, the diplopia is horizontal and worse in the distance. Diplopia is also increased on looking to the affected side and is partly caused by overaction if the medial rectus on the unaffected side as it tries to provide the extra innervation to the affected lateral rectus. These two muscles are synergists or “yoke muscles” as both attempts to move the eye over to the left or right. The condition is commonly unilateral but can also occur bilaterally. The unilateral abducens nerve palsy is the most common of the isolated ocular motor nerve palsies.
What are the causes of Sixth nerve palsy, or abducens nerve palsy?
Because the nerve emerges near the bottom of the brain, it is often the first nerve compressed when there is any rise in intracranial pressure. Different presentations of the condition, or associations with other conditions, can help to localize the site of the lesion along the VIth cranial nerve pathway.
The most common causes of VIth nerve palsy in adults are:
More common: Vasculopathic (diabetes, hypertension, atherosclerosis), trauma, idiopathic.
Less common: Increased intracranial pressure, giant cell arteritis, cavernous sinus mass (e.g. meningioma, Brain stem Glioblastoma aneurysm, metastasis), multiple sclerosis, sarcoidosis/vasculitis, postmyelography, lumbar puncture, stroke (usually not isolated), Chiari Malformation, hydrocephalus, intracranial hypertension, tuberculosis meningitis.
In children, causes are traumatic, neoplastic (most commonly brainstem glioma), as well as idiopathic. Sixth nerve palsy causes the eyes to deviate inward and rapidly recovering isolated VIth nerve palsy can occur in childhood, sometimes precipitated by ear, nose and throat infections.
What is Trismus?
Trismus is an inability to open the jaw due to tonic spasm or contracture of the
masticatory muscles, principally masseter and temporalis, effecting forced jaw
closure (‘lockjaw’). Recognized causes and associations of trismus include
• Dystonia of the jaw muscles (e.g. drug-induced dystonic reaction);
• Generalized tonic–clonic epileptic seizure;
• Neuromuscular diseases: polymyositis, tetanus, nemaline myopathy, trauma
to the muscles of mastication, rabies, strychnine poisoning;
• Infection in the pterygomandibular space;
• Metabolic disorders: Gaucher’s disease (type II);
• Central disorders: brainstem encephalopathy, multiple sclerosis, pseudobulbar palsy.
What is Impersistence?
It is defined as a transitory existence or occurrence lasting only a short time. Impersistence is used with motor skill where motor impersistence is characterized by the inability to sustain a movement.
Trombone Tongue
Trombone tongue, or flycatcher tongue, refers to an irregular involuntary darting
of the tongue in and out of the mouth when the patient is requested to keep the
tongue protruded. This sign may be seen in choreiform movement disorders such
as Huntington’s disease and neuroacanthocytosis and in tardive dyskinesia.
What is the Hoffman sign?
It refers to the results of the Hoffman test. This test is used to determine whether your fingers or thumbs flex involuntarily in response to certain triggers. The way that your fingers or thumbs react may be a sign of an underlying condition affecting your central nervous system.
What is Homan’s sign test?
Homan’s sign test also called dorsiflexon sign test is a physical examination procedure that is used to test for Deep Vein Thrombosis (DVT). A positive Homan’s sign in the presence of other clinical signs may be a quick indicator of DVT. Clinical evaluation alone cannot be relied on for patient management, but when carefully performed, it remains useful in determining the need for additional testing (like D-dimer test, ultrasonography, multidetector helical computed axial tomography (CT), and pulmonary angiography)
In performing this test, the patient will need to actively extend his knee.
Once the knee is extended the examiner raises the patient’s straight leg to 10 degrees, then passively and abruptly dorsiflexes the foot and squeezes the calf with the other hand.
Deep calf pain and tenderness may indicate presence of DVT.
What is Trömner’s Sign?
Trömner’s sign is flexion of the thumb and index finger in response to tapping
or flicking the volar surface of the distal phalanx of the middle finger, held
partially flexed between the examiner’s finger and thumb. This is an alternative
method to Hoffmann’s sign (‘snapping’ the distal phalanx) to elicit the finger
flexor response. As in the latter, it is suggestive of a corticospinal tract (upper
motor neurone) lesion above C5 or C6, especially if unilateral, although it may
be observed in some normal individuals.
What is Trousseau’s Sign?
Trousseau described the signs and symptoms of tetany, including anaesthesia,
paraesthesia, and the main d’accoucheur posture, as well as noting that the latter
could be reproduced by applying a bandage or inflating a cuff around the arm so
as to impede circulation; the latter is now known as Trousseau’s sign and indicates
latent tetany.
Trousseau also noted the concurrence of venous thrombosis and migrating
thrombophlebitis with malignant disease, also referred to as Trousseau’s sign;
this may present with cerebral venous thrombosis.
The sign is also known as main d’accoucheur (French for ” hand of the obstetrician “) because it supposedly resembles the position of an obstetrician’s hand in delivering a baby. The sign is named after French physician Armand Trousseau who described the phenomenon in 1861. It is distinct from the Trousseau sign of malignancy.
The Trousseau sign of malignancy or Trousseau’s syndrome is a medical sign involving episodes of vessel inflammation due to blood clot (thrombophlebitis) which are recurrent or appearing in different locations over time (thrombophlebitis migrans or migratory thrombophlebitis).
What is Trousseau syndrome?
The Trousseau sign of malignancy or Trousseau’s syndrome is a medical sign involving episodes of vessel inflammation due to blood clot (thrombophlebitis) which are recurrent or appearing in different locations over time (thrombophlebitis migrans or migratory thrombophlebitis).
What is a Chvostek sign?
Chvostek’s sign Chvostek sign is a contraction of ipsilateral facial muscles subsequent to percussion over the facial nerve and is considered a clinical indicator of hypocalcaemia. Positive Chvostek’s sign represents increased neuromuscular excitability caused by hypocalcaemia.
What is Skew deviation?
Skew deviation is a vertical strabismus caused by a supranuclear lesion in the posterior fossa. Because skew deviation may clinically mimic trochlear nerve palsy, it is sometimes difficult to differentiate the 2 conditions.
What is Tullio Phenomenon?
The Tullio phenomenon is the experience of vestibular symptoms and signs
(vertigo, nystagmus, oscillopsia, postural imbalance, ocular tilt reaction, +/−
skew deviation) on exposure to high-intensity acoustic stimuli, presumed to be
due to hyperexcitability of the normal vestibular response to sound, causing
pathological stimulation of the semicircular canals and/or otoliths. This unusual phenomenon may be associated with perilymph leaks or a defect in the capsule forming the roof of the anterior semicircular canal. The sound sensitivity is probably at the level of the receptors rather than the vestibular nerve.
What is Tunnel Vision?
A complaint of ‘tunnel vision’ may indicate constriction of the visual field. This
may be observed with enlargement of the blind spot and papilloedema as a
consequence of raised intracranial pressure or with a compressive optic neuropathy. The normal visual field enlarges the further away from the eye the visual
target used to map the field is held, hence there is in fact ‘funnel vision’. In nonorganic visual impairment, by contrast, the visual field stays the same size with
more distant targets (tunnel vision).
A tunnel vision phenomenon has also been described as part of the aura of
seizures of anteromedial temporal and occipitotemporal origin. A closing in of
vision may be described as a feature of presyncope.
What is a blind spot, or scotoma?
A blind spot, or scotoma, is an area on the retina without receptors to respond to light. A blind spot is actually a small area within your visual field that contains no detected vision. It may sound like a physical defect, but everyone has a natural blind spot or physiological blind spot in their vision.
What is Two-Point Discrimination?
Two-point discrimination is the ability to discriminate two adjacent point stimuli
(e.g. using a pair of callipers) as two rather than one. The minimum detectable
distance between the points (acuity) is smaller on the skin of the fingertips (i.e.
greater acuity) than, say, the skin on the back of the trunk. Impairments of two-point discrimination may occur with dorsal column spinal cord lesions, in which proprioception (and possibly vibration) is also impaired. Cortical parietal lobe lesions may produce a cortical sensory syndrome of astereognosis, agraphaesthesia, and impaired two-point discrimination.
What is Astereognosis?
It, (or tactile agnosia if only one hand is affected) is the inability to identify an object by active touch of the hands without other sensory input, such as visual or sensory information. An individual with astereognosis is unable to identify objects by handling them, despite intact elementary tactile, proprioceptive, and thermal sensation.
What is Phosphene?
A phosphene is the phenomenon of seeing light without light actually entering the eye. The word phosphene comes from the Greek words phos (light) and phainein (to show). Phosphenes that are induced by movement or sound may be associated with optic neuritis.
What is Uhthoff ’s Phenomenon?
Uhthoff ’s phenomenon or symptom is the worsening of visual acuity (‘amblyopia’ in Uhthoff’s 1890 description) with exercise in optic neuritis, reflecting the
temperature sensitivity of demyelinated axons (i.e. reduced safety factor for faithful transmission of action potentials). The term has subsequently been applied to
exercise and/or temperature related symptoms in other demyelinated pathways.
It has also been described in the context of other optic nerve diseases, including
Leber’s hereditary optic neuropathy, sarcoidosis, and tumour.
Evidence suggesting that Uhthoff’s phenomenon is associated with an
increased incidence of recurrent optic neuritis, and may be a prognostic indicator
for the development of multiple sclerosis, has been presented.
Inverse Uhthoff sign, improved vision with warming, has been described.
What is Unterberger’s Sign?
Unterberger’s sign or Unterberger’s stepping test is said to examine the integrity
of vestibulospinal connections and attempts to define the side of a vestibular
lesion. The patient is asked to march on the spot with the eyes closed (i.e. proprioceptive and visual cues are removed); the patient will rotate to the side of
a unilateral vestibular lesion (Unterberger’s sign). The test is not very useful,
particularly in chronic, progressive, or partially compensated vestibular lesions.