A large, randomized controlled trial offers new evidence on how to protect brain health.
Could a few hours a week of brain training today help protect your brain for decades?
A new study suggests the answer may be yes.
Research published Feb. 9 in the journal Alzheimer’s & Dementia found that older adults who completed 14 to 22 hours of a specific type of brain training had a 25 percent lower risk of being diagnosed with dementia 20 years later compared with those who didn’t receive the training.
The finding comes from a large, randomized controlled trial — considered the gold standard in medical research — that tracked the cognitive health of more than 2,800 healthy older adults for two decades.
The researchers said they were surprised that a relatively small amount of training focused on brain processing speed — not memory or reasoning — appeared to be linked to benefits that lasted for decades.
“The thing that’s so astonishing, it’s really a very modest amount of training,” says study author Marilyn Albert, a professor of neurology and director of the Johns Hopkins Alzheimer’s Disease Research Center. “Who would have thought?”
Alzheimer’s disease, the most common form of dementia, affects more than 7 million Americans today, according to the Alzheimer’s Association, and that number is expected to double by 2060. It’s also one of the conditions older adults fear most.
Brain researchers say they hope the findings will encourage older adults to stay cognitively active and engaged — to keep learning new things in their daily lives, rather than rushing out to buy a brain-training program.
Brain experts: More research needed
Two Alzheimer’s disease specialists not involved with the study say the results are intriguing, but they urged caution, pointing to several limitations. Among them: The study doesn’t account for participants who dropped out over time, and the Alzheimer’s disease diagnoses were based on Medicare records rather than biological markers such as amyloid plaques or tau proteins in the brain.
“I’m both skeptical but also somewhat impressed,” says Dr. Andrew Budson, a neurologist and associate director of the Alzheimer’s Disease Research Center at Boston University. “It’s really quite rare for any computerized-game brain training study to show positive results — and to show effects on a diagnosis of Alzheimer’s disease 20 years later.”
He says more research is needed to confirm the findings.
Dr. Ron Petersen, director of the Mayo Clinic Alzheimer’s Disease Research Center in Rochester, Minnesota, similarly stressed that the results are interesting but not definitive.
“These things might be beneficial, but I wouldn’t go to the bank with this,” he says.
Nonetheless, both experts note that the study reinforces a familiar message when it comes to brain health: Staying mentally engaged matters.
The study design
To conduct the study, researchers randomly assigned cognitively healthy people 65 and older to one of three types of brain training — speed, memory or reasoning — or to a control group. They were asked to complete two 60- to 75-minute sessions a week for five or six weeks.
In addition, about half of the people in each group were randomly assigned to do “booster” training — four sessions at the end of the first year and another four at the three-year mark.
The researchers then used Medicare records to see who had been diagnosed with Alzheimer’s disease or dementia 20 years later. At follow-up, the average surviving participant was almost 94 years old.
They found that those who completed the speed-based training and later participated in booster sessions saw a 25 percent reduction in dementia risk. Participants in the other training groups and those who skipped the booster training also had a lower risk of dementia, but it was not enough to be statistically significant.
The benefit of the speed-based training was consistent regardless of participants’ age at the time of training, Albert says.
What type of brain training worked?
The speed training targeted something called speed of processing — essentially how quickly your brain takes in information and reacts. It relies on what scientists call implicit learning, or learning by doing rather than memorizing, Albert says.
Participants saw images on a screen and had to make quick decisions while also noticing objects in their peripheral vision, she explains. The exercises also became more challenging as users improved.
“You’re switching your attention back and forth between these two things and trying to make decisions very rapidly,” Albert says. “The task itself is pretty demanding.”
Researchers aren’t sure why speed training worked while the other exercises did not.
One possibility is that it may help build “brain reserve,” allowing the brain to function longer despite age-related changes. Albert speculates that the training could improve brain connectivity, “to make different parts of the brain work better together.”
A version of the training program used in the research is now available commercially through the BrainHQ website and app. The exercise, called “Double Decision,” is offered as part of a paid subscription service. (One of the authors disclosed financial ties to Posit Science, the company that markets the training.)
What this means for brain health
Budson and Petersen emphasize that the study is best viewed as more evidence on the importance of staying cognitively active and engaged rather than an endorsement of a particular brain-training product.
Budson says activities such as learning a new instrument or playing pickleball can challenge the brain in similar ways to the speed-of-processing training by building skills that become more automatic with practice.
“I personally would never encourage someone to do computerized brain training games at home,” says Budson, author of Why We Forget and How to Remember Better: The Science Behind Memory. “I want people to be out in the world.”
He says he believes computerized brain training is worthwhile only as an alternative to passive screen time like watching TV: “If someone is debating, ‘Should I watch television for three hours or do computer games for three hours?’ my answer is yes, it would be better to do the computer games,” he says.
Petersen, of the Mayo Clinic, says brain training is best viewed as part of a broader approach to brain health and should be paired with other evidence-based strategies such as exercise, social engagement and managing cardiovascular health.
“The take-home message,” he says, is that “yes — absolutely — keeping yourself intellectually active and using your brain as you age is good advice.”