Could a few hours of focused brain training really help stave off dementia for decades? According to a landmark study published on February 9, 2026, in Alzheimer’s & Dementia: Translational Research & Clinical Interventions, the answer may be a resounding yes. The findings, which have been hailed as the strongest evidence yet for the long-term benefits of cognitive training, suggest that specific mental exercises—particularly those designed to speed up brain processing—could have profound effects on aging brains.
The research, known as the ACTIVE (Advanced Cognitive Training for Independent and Vital Elderly) trial, tracked nearly 3,000 healthy adults aged 65 and older from six different regions across the United States. Funded by the National Institutes of Health, the study spanned a remarkable 20 years, making it one of the most rigorous and long-term investigations into cognitive training and dementia risk to date. Participants were randomly assigned to one of three cognitive training programs—memory, reasoning, or speed processing—or to a control group that received no training at all.
Each participant initially took part in up to 10 one-hour training sessions over five to six weeks. The speed training group, in particular, focused on rapidly processing and responding to visual information—a skill not unlike the split-second decision-making drivers need when navigating busy roads. For example, participants would quickly identify objects on a screen and make decisions about them, all while managing distractions. About half of the participants in each training group received additional booster sessions over the following three years, bringing the total training time for some up to 23 hours.
After two decades, the results were striking. Those who completed 14 to 23 hours of speed training had a 25% lower risk of being diagnosed with dementia compared to those who didn’t receive the training. This benefit was not observed in the groups that received memory or reasoning training, nor in those who skipped the booster sessions. According to NBC News, the study’s lead author, Marilyn Albert, director of the Johns Hopkins Alzheimer’s Disease Research Center, expressed her surprise: “It’s very surprising. It’s not at all what I would have expected.”
The implications of these findings are significant, especially as the U.S. faces a looming Alzheimer’s crisis. The Alzheimer’s Association estimates that over 7 million Americans are currently living with the disease, a number expected to nearly double by 2060. Women, in particular, are at heightened risk, developing dementia at nearly twice the rate of men. The ACTIVE trial included a majority of female participants and roughly 25% minorities, making its findings broadly applicable.
But why did speed training outperform memory and reasoning exercises? The answer may lie in the brain’s remarkable adaptability, or neuroplasticity. Dr. Sanjula Singh, a physician-scientist at Harvard Medical School, explained to NBC News that speed training emphasizes implicit learning—the kind of unconscious skill-building that, once acquired, tends to stick. She likened it to learning to ride a bike: “A child can learn how to ride a bike in about 10 hours, and afterwards that learning lasts a lifetime.”
Marilyn Albert suggested that speed training might engage broader neural networks, building what experts call cognitive reserve—the brain’s resilience against age-related decline. Dr. Kellyann Niotis, a preventive neurologist at Weill Cornell Medicine, elaborated: “This visual processing speed-based training may be engaging broader neuronal networks that are actually building more brain resilience or more cognitive reserve.”
Another unique aspect of the speed training program was its adaptability. As Albert told NBC News, the training became more challenging as participants improved, pushing their brains to process information even faster. This dynamic approach may help explain why the benefits endured for decades.
Despite the excitement, experts urge caution. As reported by AARP, Dr. Andrew Budson of Boston University’s Alzheimer’s Disease Research Center described himself as “both skeptical but also somewhat impressed.” He pointed out several limitations, including the study’s reliance on Medicare records for dementia diagnoses rather than biological markers like amyloid plaques or tau proteins. Additionally, the study did not account for participants who dropped out over the years, which could potentially skew the results.
Dr. Thomas Wisniewski, director of cognitive neurology at NYU Langone Health, called the results “astonishing,” adding, “It’s really the first clear documentation in a randomized controlled trial that at least some form of cognitive training can lower the risk of dementia.” Still, both he and Dr. Budson emphasized the need for further research to confirm these findings and to better understand the mechanisms at play.
For those wondering whether to rush out and purchase a brain-training app, the consensus among researchers is more measured. While the speed training used in the study has since been commercialized as the “double decision” exercise on the BrainHQ platform, Albert recommends that older adults simply strive to stay cognitively active and engaged in daily life. “Anyone with a brain is at risk of Alzheimer’s and everyone out there should be paying attention to their brain health,” said Dr. Richard Isaacson, a preventive neurologist at the Institute for Neurodegenerative Diseases in Boca Raton, Florida.
Moreover, experts highlight that dementia risk is influenced by a host of modifiable factors. According to a 2024 report by the Lancet Commission, nearly half of all dementia cases could be delayed or prevented by addressing risk factors such as hearing loss, vision impairment, hypertension, diabetes, and physical inactivity. Dr. Niotis advises her patients to get their hearing checked, manage metabolic risk factors, correct vision problems, and stay physically active. There’s even emerging evidence that vaccines, like the shingles shot, may reduce dementia risk—a 2025 Nature study found a 20% lower risk among vaccinated individuals over seven years.
In related health news, a recent study from the National Institutes of Health found that intermittent fasting—eating only within an eight-hour window—can reduce Crohn’s disease symptoms by 40% and inflammation by 50%, with relief often seen in just 12 weeks. And research from New York University’s School of Public Health suggests that anxiety about aging can actually accelerate biological aging at the cellular level, reinforcing the advice to “age with grace and don’t worry.”
As the population ages and the specter of dementia looms larger, the ACTIVE trial offers a glimmer of hope. A modest investment of time in targeted cognitive training, particularly exercises that challenge the brain’s processing speed, may help preserve memory and independence well into old age. While more research is needed to fully unlock the secrets of the aging brain, the message is clear: keeping the mind active could be one of the most powerful tools in the fight against dementia.