10 Hours of Brain Training May Cut Dementia Risk 25%

Imagine if you could dramatically lower your dementia risk with less time than it takes to binge-watch a TV series. Scientists just proved you can.

A federally funded study tracking 2,802 older adults for two decades found something remarkable. Those who completed just eight to 10 hours of cognitive speed training in the 1990s were 25% less likely to develop dementia over the next 20 years.

"We now have a gold-standard study that tells us that there is something we can do to reduce our risk for dementia," says Dr. Marilyn Albert, a neurology professor at Johns Hopkins University School of Medicine. The study appears in the journal Alzheimer's & Dementia.

The training involves a specific type of brain exercise that boosts processing speed. Participants watch a computer screen where vehicles flash briefly in the center while road signs appear on the edges. The challenge is identifying the correct vehicle and remembering where the sign appeared, all while the images get harder to distinguish and distractions multiply.

Think of it like learning to ride a bike. Neuroscientist Henry Mahncke explains that this type of training triggers implicit learning, which creates unconscious skills that stick with you for life. Even after 20 years without practice, your brain retains what it learned.

George Kovach, 74, from Vienna, Virginia, started doing these exercises a decade ago. "I was interested in taking care of my neurons," he says. He's now completed over 1,300 sessions using an online program called BrainHQ, which includes the same exercises from the study.

The Bright Side

What makes this discovery especially exciting is how accessible it is. Unlike many medical interventions, this approach requires no prescription, no expensive equipment, and minimal time investment. Ten hours of training with occasional booster sessions proved enough to make a measurable difference decades later.

Jennifer O'Brien, an associate professor of psychology at the University of South Florida, calls the long-term effects "super-exciting." The fact that such a modest amount of effort can provide protection for 20 years gives people a practical tool for brain health.

An ongoing study called the Preventing Alzheimer's with Cognitive Training (PACT) is testing whether more training provides even greater benefits. With 7,500 participants completing 45 sessions over several years, researchers expect results by 2028 that could further refine recommendations.

For now, the message is clear and hopeful: a small investment in brain training today could pay dividends for decades to come.