A large, long-term clinical trial has found that a specific type of brain training video game may reduce the risk of dementia for decades. Participants who completed targeted “speed training” exercises for up to 23 hours over three years had a 25% lower risk of developing Alzheimer’s disease and other dementias over a 20-year follow-up period. Experts describe the findings as the strongest evidence to date that certain forms of cognitive training can produce lasting, protective changes in the brain.

The results come from an extended analysis of the federally funded Advanced Cognitive Training for Independent and Vital Elderly, or ACTIVE, trial.

Key Findings from a 20-Year Study

The ACTIVE study enrolled nearly 3,000 adults aged 65 and older with no significant cognitive impairment at baseline. Participants were randomly assigned to one of three training programs: speed training, memory training, or reasoning training. A control group received no cognitive intervention.

All participants initially completed up to 10 training sessions over five weeks. About half in each group later received booster sessions, totaling up to 23 hours of training across three years. Over the next two decades, researchers tracked dementia diagnoses using Medicare records.

Only those who completed speed training and received booster sessions showed a significant benefit. This group experienced a 25% reduction in dementia risk compared with controls. Participants in memory or reasoning training did not demonstrate a protective effect.

Why Speed Training May Work

Speed training focuses on improving how quickly and accurately the brain processes visual information. Exercises require participants to rapidly identify objects on a screen and make decisions, a skill similar to monitoring multiple stimuli while driving.

Researchers believe this form of training may promote neuroplasticity, the brain’s ability to reorganize and strengthen neural connections. Unlike explicit learning, such as memorizing facts, speed training may rely more heavily on implicit learning systems, which are known to produce durable changes in brain circuitry.

Another factor may be the adaptive nature of the training. The difficulty level adjusted based on participant performance, continually challenging users at progressively higher speeds. This may have engaged broader neural networks and contributed to increased cognitive reserve, the brain’s resilience against age-related decline.

Implications and Practical Considerations

The specific program used in the study has since evolved into an exercise known as “Double Decision,” now available through the BrainHQ platform. Based on the trial’s findings, some experts suggest that adults over 65 may consider incorporating similar speed-based cognitive exercises into their routines.

However, researchers caution that dementia prevention is multifaceted. Cognitive training is not a singular solution, and further research is needed to determine whether starting earlier in life yields similar benefits.

Broader Strategies for Brain Health

Approximately 7 million people in the United States are currently living with Alzheimer’s disease, a number projected to nearly double by 2050. Experts estimate that nearly half of dementia cases could be delayed or prevented by addressing modifiable risk factors.

Recommended measures include managing blood pressure, cholesterol and blood sugar; treating hearing and vision impairments; engaging in regular physical exercise; and maintaining social and cognitive activity. Emerging evidence also suggests that certain vaccinations, such as the shingles vaccine, may be associated with lower dementia risk, though further study is ongoing.

Conclusion

The long-term results of the ACTIVE trial provide compelling evidence that targeted speed-based cognitive training may lower dementia risk in older adults. While not a standalone prevention strategy, structured brain training could become a valuable component of broader efforts to support lifelong cognitive health.