A large multisite, randomized, controlled clinical trial has found that cognitive training can benefit seniors up to a decade after they’ve received the training.
The study was headed by George Rebok, Ph.D., a professor at the Johns Hopkins University Bloomberg School of Public Health, with findings published online January 13 in the Journal of the American Geriatrics Society.
The cohort consisted of an ethnically diverse volunteer sample of some 2,800 individuals who had an average age of 74 at the start of the study. Half underwent 10 training sessions for reasoning, speed-of-information processing, and memory tasks, and half served as controls. Reasoning training focused on improving the ability to solve problems that contained a serial pattern. Speed-of-processing training focused on visual searches and the ability to process increasingly more complex information presented in successively shorter inspection times. Memory training focused on improving verbal episodic memory through instruction and practice in strategy use.
Each training intervention produced large and statistically significant improvements in the trained cognitive ability. Subjects’ capabilities in the three cognitive areas were also evaluated up to a decade later, as was their ability to function in daily life—for instance, handle meal preparation, housework, finances, shopping, or dressing. At the 10-year follow-up, the training group was found to have better cognitive and functional status than the control group.
For instance, at the 10-year evaluation, most of the subjects who had received training in reasoning and processing speed were at or above their baseline level for the trained cognitive ability. This was not the case for the controls. And also at the 10-year evaluation, about 60 percent of trained participants, versus 50 percent of controls, were at or above their baseline level of daily functioning—a significant difference.
However, the results were not a panacea for the cognitive decline that can accompany old age.
For example, the effects of cognitive training on daily functioning were modest. The reason why, the researchers suggested, “is probably because many factors beyond cognition affect daily function and functional independence, including sex, social class, mood, sarcopenia, obesity, chronic diseases, and social isolation.”
And while the impact of training in reasoning and speed processing endured for a decade, the impact of memory training started to decline at five years after training. “Others have [also] reported the absence of long-term memory training effects,” the researchers noted. “It is possible that the memory training used in [our trial] requires more-extensive practice or greater dosing to reach durability levels than reasoning or speed training. It is also possible that age-related structural changes in the medial temporal lobe, including age-related neuropathology and even incipient Alzheimer’s disease in some participants, limits the durability of memory training in older adults.”
Even with such shortcomings, though, the researchers believe that their results have far-reaching clinical implications. As they said in their report, “These results provide support for the development of other interventions, particularly those that target multiple cognitive abilities and are more likely to have an effect on daily living performance. Such interventions hold the potential to delay onset of functional decline and possibly dementia and are consistent with comprehensive geriatric care that strives to maintain and support functional independence.”
Indeed, they noted, “If interventions that could delay onset of functional impairment by even six years were introduced, the number of people affected by 2050 would be reduced by 38 percent [according to projections reported in the May 2002 Annual Review of Public Health]. That would be of great public-health significance.”
“One of the most common questions asked by our older patients is, ‘What can I do to prevent memory loss?,” Art Walaszek, M.D., an associate professor of psychiatry at the University of Wisconsin and a geriatric psychiatrist, said in an interview with Psychiatric News. “This study, impressive for its large sample size and long-term follow-up, helps answer this question. . . . The investigators had already found benefit at five years and now extend their findings to 10 years. It appears that cognitive training may help older adults with their reasoning skills, processing speed, and activities of daily living, but not with memory. This raises the intriguing possibility that, though memory decline may be difficult to avoid, older adults may be able to develop other cognitive skills in order to maintain their functioning.”
The study was funded by the National Institute on Aging and the National Institute of Nursing Research. ■