A certain type of brain training appears to prevent or delay dementia by some 25% in people older than age 65, according to new research.
Surprisingly, it wasn’t memory or problem-solving tasks that moved the needle — it was an interactive computerized game that tested the ability to recognize two separate images in faster and faster sequences.
The game shows the user one of two vehicles in a desert, town or farmland setting. Next, a Route 66 sign appears briefly along the periphery, surrounded by additional distracting road signs. To do the training accurately, the player must click on the correct car or tractor and the location of the Route 66 sign. As players improve, the images disappear increasingly quickly.
“It’s what we call a task of divided attention in which you don’t have a conscious strategy on how to improve,” said study coauthor Dr. Marilyn Albert, a professor of neurology at the Johns Hopkins University School of Medicine and director of the Johns Hopkins Alzheimer’s Disease Research Center in Baltimore.
“You’re just trying the best you can to figure out how to divide your attention,” she said. “It was also adaptive, in the sense that as people did better, it got harder.”
Unconscious learning
Initiated in 1998, the Advanced Cognitive Training for Independent and Vital Elderly, or ACTIVE, trial tested three types of cognitive training on more than 2,800 volunteers with an average age of 74. All were free of dementia at the start and lived independently in six communities around the United States. A fourth group who received no training served as a control.
“A real strength of the study is this was a really representative population — 25% of the participants were minorities,” Albert said. “So we can truly say the findings generalize to the entire US population.”
One group was focused on memory, learning techniques for remembering word lists, text materials and details of stories. A second group underwent training focused on reasoning, such as solving problems and identifying patterns that could help with daily life.
A third group used a split-attention speed brain game developed by professors in Alabama and Kentucky. Sold in 2008 to the owners of BrainHQ, a for-profit brain-training company, the updated game now goes by the name Double Decision. (Other brain-training companies have also developed similar speed games.)
Adaptive dual-attention games use implicit learning, which is an automatic acquisition of knowledge or skills without conscious awareness of what is being learned. Implicit learning uses different parts of the brain than solving problems or understanding the meanings of words, Albert said.
Examples include tying shoelaces, reacting to social cues and learning to ride a bike.
“If you don’t ride a bicycle for 10 years, you can get on a bicycle and ride it. We know this type of learning is very long-lasting,” Albert said.
However, an important distinction exists between acquiring a skill and expecting it to confer broad benefits in other areas such as preventing dementia, said Walter Boot, an Irving Sherwood Wright professor of geriatrics at Weill Cornell Medicine and associate director of its Center on Aging and Behavioral Research in New York City. He was not involved in the study.
“One can learn to ride a bicycle and still remember how to do so 20 years later, just as one can learn the ‘speed of processing’ task in the study and continue to perform well on that task many years later,” Boot said in an email. “What remains unclear is how either of these activities would translate into a reduced risk of dementia.”
Extra practice necessary
Initially, the program was intense. Volunteers were trained in person twice per week for 60 to 75 minutes per session over five weeks. At the end of the first year, about half of the people in each cognitive training group underwent an additional “booster” of four one-hour sessions. Another four hours of training was also done at the end of the third year of the study, for a total of 22.5 hours.
No more official training was done, yet when investigators compared the three groups with their Medicare records 20 years later, they found it was only the dual-attention speed game that contributed to a 25% reduction in dementia diagnoses compared with the control group.
That benefit, however, was only for a subset of the volunteers, according to the study published Monday in the journal Alzheimer’s & Dementia: Translational Research & Clinical Interventions.
“The 25% reduction in risk for dementia was only in people who had the original training on the speed game and then the booster sessions. If you didn’t have the booster sessions, you didn’t benefit,” Albert said.
While insights from a 20-year study are valuable, the research did not have the data needed to show a definitive connection between the computerized training and the prevention of dementia, said Dr. Susan Kohlhaas, executive director of research and partnerships at Alzheimer’s Research UK, a nonprofit research center based in Cambridge. She was not involved in the study.
“Diagnoses were identified through health records rather than specialist clinical testing, so we do not know whether this training changed the underlying diseases that cause dementia or affected specific types of dementia,” she said in a statement.
While memory and reasoning training did not lower the risk for dementia, earlier publications using data from the ACTIVE trial found both do improve memory and executive reasoning, she said. Such training also helps people with skills that enable them to live independently in their own homes.
Why speed training might help the brain
Why did only fast-paced split-attention cognitive training work against dementia? More importantly, why would only 22.5 hours of such training appear to last over years? While more research is needed to understand the results, Albert has some educated guesses.
“First, the game is quite demanding and not particularly fun,” Albert said. “To do it for an hour twice a week is hard work. You’re pushing your brain in a way that it wouldn’t normally do.
“So, it’s possible that speed training activates neurons across the brain, creating greater connectivity and increasing plasticity,” she said.
The game was also adaptive in that it became harder as people progressed and easier when they failed, said Alzheimer’s prevention researcher Dr. Richard Isaacson, director of research at the Institute for Neurodegenerative Diseases in Florida.
Such interactivity “exercises the brain in new ways that can contribute to the cognitive reserve needed to delay dementia,” said Isaacson, who was not involved in the study.
Cognitive reserve is the brain’s ability to adapt and maintain normal function despite the presence of underlying damage, aging or disease. In Alzheimer’s disease, for example, people with more cognitive reserve often delay the onset of symptoms despite the presence of the amyloid and tau, two proteins that are the hallmark signs of the neurological disorder.
There could be another factor involved in the game’s long-term positive impact. An October study found speed training may preserve acetylcholine, a neurotransmitter that makes the brain more awake, focused and attentive.
“We’re talking about a fundamental physical chemical change that we know really matters as a contributor to brain health,” Dr. Michael Merzenich, professor emeritus at the University of California, San Francisco, told CNN in an earlier interview. Merzenich is the cofounder and chief scientific officer of Posit Science, which owns BrainHQ.
While researchers work out the answers, experts say cognitive training is just one part of the journey toward improving brain health.
“Alzheimer’s and other dementias are complex disorders. You can’t just eat a magic blueberry or play a game on your cell phone or do any one single thing,” Isaacson said.
“You need the entire cocktail — eating a brain-healthy diet, exercising regularly, modifying blood pressure, getting quality sleep, reducing stress, positive relationships — all of these are necessary for brain health.”