A landmark 20-year study of nearly 3,000 older adults finds that a short course of computerized brain training can lower dementia risk decades later. The results suggest that it may never be too late to start strengthening cognitive skills.
A few hours of brain training in later life may pay off for decades, according to a landmark study that followed nearly 3,000 older adults for 20 years.
The researchers report that older adults who completed a specific type of computerized “speed of processing” training — plus a handful of booster sessions — were 25% less likely to be diagnosed with dementia over the next two decades than peers who received no training.
The findings come from the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) trial, one of the largest and longest-running randomized studies of cognitive training in healthy older adults. The new analysis, published in the journal Alzheimer’s & Dementia: Translational Research and Clinical Interventions, is among the first from a large controlled trial to show that any kind of intervention can lower the incidence of Alzheimer’s disease and related dementias.
The results surprised even the scientists who have been tracking participants since the late 1990s.
“Participants who had the greatest advantage had a maximum of 18 training sessions over three years. It seemed implausible that we might still see benefits two decades later,” Michael Marsiske, one of the study’s principal investigators and a professor and interim co-chair of the Department of Clinical and Health Psychology at the University of Florida College of Public Health and Health Professions, said in a news release.
The ACTIVE study enrolled 2,832 older adults and randomly assigned them to one of three training programs — memory, reasoning or speed of processing — or to a control group that received no cognitive training. Training consisted of 10 sessions lasting 60 to 75 minutes, held over about six weeks. Some participants were randomly selected to receive booster sessions 11 and 35 months after the initial training.
Earlier follow-ups had already shown that the training produced lasting benefits. Five years after the initial sessions, participants in all three training groups reported less difficulty with everyday tasks such as cooking, taking medications and managing finances compared with the control group. At 10 years, those who had received reasoning and speed training still showed measurable cognitive advantages.
“Our initial findings had shown benefits of several training arms up to 10 years after training, with participants reporting fewer impairment in tasks of daily living and experiencing fewer motor vehicle crashes. Adding in these 20-year findings strongly suggests that engagement in cognitive training does no harm and may confer substantial benefit,” Marsiske added.
The new 20-year analysis focused on dementia diagnoses. By this point, most surviving participants were in their 90s. Investigators reviewed medical records to determine how many had developed dementia and compared rates across the original training and control groups.
Only the speed of processing training — not the memory or reasoning programs — was linked to a significantly lower risk of dementia. Participants who completed the speed training and booster sessions reduced their risk by about one-quarter compared with those who never trained.
The speed training used in ACTIVE asks participants to process visual information on a computer screen and make quick decisions, such as identifying or locating targets amid distractions. As people improve, the program automatically becomes more challenging, forcing the brain to work faster and more accurately.
The researchers think that this adaptive, personalized design may be key to its durability. By continually pushing participants to operate at the edge of their ability, the training may strengthen and rewire brain networks involved in attention, visual processing and rapid decision-making. Over time, those changes could help the brain better compensate for age-related decline.
The specific speed training program tested in the study is now commercially available through the company BrainHQ.
For people wondering if they are too old to benefit from brain training, the ACTIVE results offer encouraging news.
“At enrollment, our participants ranged in age from 65 to 94 years,” added Marsiske. “We found no substantial reduction of training benefit with age, suggesting that training can be started at any time.”
That message aligns with a growing body of research suggesting that brain health in later life is shaped not only by genetics and medical conditions, but also by lifestyle factors such as physical activity, social engagement, cardiovascular health and mentally stimulating activities. While no single strategy can guarantee protection from dementia, combining several may offer the best chance of preserving independence.
The ACTIVE trial has already inspired new lines of research. The investigators are launching follow-up studies, testing updated interventions and exploring whether pairing cognitive training with other habits — such as exercise, nutrition and blood pressure control — can further reduce dementia risk.
“We think this study encourages us, and the field, to continue incorporating cognitive training into multicomponent intervention programs for older adults,” Marsiske added.
For now, the 20-year findings underscore a hopeful takeaway: even relatively brief, structured brain training in later life can have long-lasting effects. As the population ages and dementia cases rise, that kind of low-risk, scalable tool could become an important part of public health efforts to help older adults stay sharper, safer and more independent for as long as possible.
Source: University of Florida Health