Major brain disease risk can be avoided: Long-term research reveals the one type of training that actually works

A large government-backed study that tracked older adults for two decades has found that one specific type of brain training may lower the risk of dementia by 25 percent. The findings are being described by several neurologists as some of the strongest evidence so far that certain cognitive exercises can have lasting effects.

The research comes from the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) trial, funded by the National Institutes of Health. The results were published in Alzheimer's & Dementia: Translational Research & Clinical Interventions.

How The Study Was Conducted

The trial began in the late 1990s and included more than 2,800 adults aged 65 and older. Participants were living independently and did not show signs of cognitive impairment at the start. A majority were women, who are known to face a higher lifetime risk of dementia. Volunteers were randomly assigned to one of four groups: speed training, memory training, reasoning training, or a control group that received no training.


The sessions ran for five weeks, with participants attending hour-long classes twice a week. About half of those in the training groups later received booster sessions over the next three years. In total, the structured training time was under 24 hours. Over the next 20 years, researchers tracked dementia diagnoses using Medicare records. Different types of dementia, including Alzheimer’s and vascular dementia, were grouped together.

The Clear Winner: Speed Training

Only one group showed a measurable benefit. Participants who completed both the initial speed training and the booster sessions had a 25 percent lower risk of developing dementia compared with the control group. Memory and reasoning training did not show the same effect.

Dr. Marilyn Albert, director of the Johns Hopkins Alzheimer’s Disease Research Center, said the result was unexpected and not something she had predicted. She also described the speed training as disproportionately beneficial during long-term follow-ups. The speed-based program focused on visual processing and divided attention. Participants were asked to quickly identify objects on a screen, including items appearing in their peripheral vision. The task became harder as performance improved.

As per NBC, Dr. Sanjula Singh of Harvard Medical School explained that once the brain rewires for these kinds of skills, the changes can last even without continued practice. She compared it to learning to ride a bicycle, where the skill remains over time. Dr. Richard Isaacson, a preventive neurologist in Florida who was not involved in the study, said relatively small efforts may pay off for decades. Dr. Thomas Wisniewski of NYU Langone Health called it the first clear documentation in a randomized controlled trial that at least some form of cognitive training can lower dementia risk.

Why Might It Work?

Researchers believe speed training may rely more on implicit learning, which involves automatic and unconscious skill-building. This differs from explicit learning used in memory drills. Albert suggested the training may have influenced connectivity in the brain, though the exact mechanism is still unclear. Some experts also think the adaptive nature of the exercise, meaning it becomes more challenging as users improve, may be key.

Dr. Kellyann Niotis of Weill Cornell Medicine said visual processing speed-based training may engage broader brain networks and build cognitive reserve, which helps the brain resist damage over time. Still, some researchers urged caution. Rachel Richardson from the Cochrane Collaboration noted that while the results were statistically significant, the margin of error means the effect size could vary. Baptiste Leurent of University College London said further research is needed before drawing firm conclusions.

Dementia Risk And What Else Helps

Dementia remains a growing public health issue. According to the World Health Organization, it affects 57 million people globally and is the seventh leading cause of death.

Experts stress that no single intervention can prevent dementia. The 2024 Lancet Commission report found that nearly half of dementia cases could be delayed or reduced by addressing modifiable risk factors. Doctors recommend managing blood pressure, cholesterol and blood sugar, correcting hearing and vision problems, and staying physically active. Some emerging research has also linked the shingles vaccine to lower dementia risk, though more studies are needed.

For now, researchers say this specific form of speed training appears promising, especially for adults over 65. Whether starting earlier in life offers added protection is still being studied.

The main takeaway is simple. Not all brain games are equal. This long-running trial suggests that training focused on visual speed and divided attention may have real and lasting impact — but experts agree more work needs to be done before it becomes a standard prescription.