Brain training may delay dementia
Study finds computer exercises for older adults could cut their chances of cognitive decline by nearly half.
If you’re intent on keeping dementia at bay, new research suggests you’ll need more than crossword puzzles, aerobic exercise and an active social life.
In a study released this week, researchers found that older adults who did exercises to shore up the speed at which they processed visual information could cut by nearly half their likelihood of cognitive decline or dementia over a 10-year period.
The clinical trial results, presented at the Alzheimer’s Assn.’s international conference in Toronto, establish specialized brain training as a potentially powerful strategy to prevent afflictions, including normal aging, that sap memory and reduce function.
With 76 million baby boomers reaching the age of maximum vulnerability to Alzheimer’s — and with no effective treatments available to alter the disease’s progression — researchers are keen to find ways to prevent or delay the onset of the memory-robbing disease. The new research suggests that even years after it is administered, an inexpensive intervention without unwanted side effects might forestall dementia symptoms.
The results emerged from a 10-year study that compared the effects of three forms of brain training in a group of 2,802 cognitively healthy seniors. The ACTIVE study — short for Advanced Cognitive Training for Independent and Vital Elderly — was funded by the National Institute on Aging.
A quarter of the participants, who had an average age of 73.4 at the study’s start, got no training at all. The remaining subjects were divided into three groups and, over five weeks, each group got 10 hourlong training sessions.
One got a classroom course designed to impart strategies aimed at boosting memory; a second got a classroom course designed to sharpen participants’ reasoning skills. A third group was given computerized training designed to increase the speed at which the brain picks up and processes cues in a person’s field of vision.
Speed of visual processing is a cognitive skill that declines with age, a trend that some neuroscientists attribute to the increasing “noise” in electrical communications between cells and among regions in the brain.
Over the study’s 10-year followup, 14% of participants in the control group suffered significant cognitive decline or dementia, compared with 11.4% in the memory-strategies training group, 11.7% in the reasoning-strategies training group and 10.5% in the speed-of-processing group.
Cognitive decline or dementia was not only less common among those in the speed-of-processing group; when it appeared, it came later.
Statistically, the trial’s four groups experienced sizable differences in cognitive aging.
For those who got the commercially available brain-training exercises, the cumulative risk of developing cognitive decline or dementia over 10 years was 33% lower than for participants who got no training at all. Among a smaller group of computerized training participants who got “booster sessions” — at least one refresher class 11 and 35 months after the initial training — the risk of cognitive decline or dementia went down even further. Compared with study participants who got no training at all, recruits who got more than 10 of the computerized brain-training sessions were 48% less likely over 10 years to experience dementia or cognitive decline.
Participants who took part in the other two training regimens, which focused on teaching strategies for remembering and for reasoning, were as a group slightly less likely than the control group to suffer cognitive decline or dementia over the study’s 10-year span. That was particularly true for those who got 10 sessions to improve reasoning strategies. But the results of those training regimens were less robust than those for the computerized training, and researchers could not rule out the possibility they were caused by chance.
In the ACTIVE trial, participants’ cognitive health was measured at one, two, three, five and 10 years after initial training took place. Researchers gauged participants’ mood, confidence and self-rated health, and surveyed their ability to conduct such daily tasks as preparing meals, driving and taking care of finances.
The computerized braintraining exercise is commercially available as the “Double Decision” game, one of a suite of cognitive exercises marketed online by the San Francisco-based Posit Science Corp. The game exercises an individual’s ability to detect, remember and respond to cues that appear and disappear quickly in varying locations on a computer screen. It uses colorful graphics and challenges players with escalating difficulty as their proficiency increases.
In an interview, UC San Francisco neuroscientist Michael Merzenich, chief scientific officer of Posit Science, said that the seemingly narrow skill of processing visual cues appears to be a pretty good indication of a person’s overall cognitive health. The new study suggests that when visual processing skills are improved by programs designed to build up those mental “muscles,” people not only perform better in tests of that specific skill, they get better at a wide range of complex behaviors, he said. The cognitive benefits, in short, appear to be “generalized.”
For companies marketing brain-training computer programs, now a multimillion-dollar industry, claims of such generalized cognitive benefits have generated criticism and controversy. In 2014, neuroscientists gathered under the auspices of the Stanford Center on Longevity took the braintraining industry to task for promising results that were “frequently exaggerated and at times misleading.”
Though such exercises can produce performance improvements in the lab, they wrote, “these small, narrow, and fleeting advances are often billed as general and lasting improvements of mind and brain.” Despite bold marketing claims, “compelling evidence of general and enduring positive effects on the way people’s minds and brains age has remained elusive,” they wrote in a December 2014 consensus statement.
University of South Florida associate professor Jerri Edwards, first author of the new study, said the ACTIVE study’s findings appear to be a milestone — “the first time a cognitive training intervention has been shown to protect against cognitive impairment or dementia in a large, randomized, controlled trial.”
Among the study’s most intriguing findings, Edwards said, was the suggestion that with continued brain training — an increased dose — older people might further boost their protection against dementia.
“Next,” she said, “we’d like to get a better grasp on what exactly is the right amount of cognitive training to get the optimal benefits.”