Older adults who completed a short course of computer-based speed-of-processing training and returned for a handful of booster sessions were 25 percent less likely to be diagnosed with Alzheimer's disease or a related dementia two decades later.
The finding comes from the ACTIVE trial, which enrolled 2,802 adults aged 65 and older in 1998-1999 and tracked them through Medicare records for 20 years.
The results, from a Johns Hopkins-led team, were published in February 2026 in Alzheimer's and Dementia: Translational Research and Clinical Interventions. It is the first randomized study to link a specific type of cognitive training to dementia outcomes over such a long follow-up.
What speed-of-processing training actually is
Speed-of-processing training is not crosswords or word puzzles. Participants viewed images on a computer screen, made rapid decisions and watched their peripheral vision, and the tasks got progressively harder as they improved.
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The initial program in ACTIVE was up to 10 sessions of about 60 to 75 minutes, spread over five to six weeks. Roughly half of the trained participants were then randomly assigned to booster sessions, four at 11 months and another four at 35 months. With the boosters included, the total came to as much as 22 hours of training over more than three years.
The booster sessions were the difference
Only the boosted speed group showed a benefit. In the Medicare analysis, which followed 2,021 of the original participants, boosted speed training carried a hazard ratio of 0.75, a statistically significant 25 percent lower rate of diagnosed dementia compared with untrained controls. Speed training without boosters showed no effect (HR 1.01).
Memory and reasoning training, the two other arms of ACTIVE, also produced numerically lower dementia rates, but the differences did not reach statistical significance. That is a departure from earlier ACTIVE reports, which had tied reasoning and memory training to short-term gains in day-to-day functioning.
"Seeing that boosted speed training was linked to lower dementia risk two decades later is remarkable because it suggests that a fairly modest nonpharmacological intervention can have long-term effects," said Marilyn Albert, director of the Alzheimer's Disease Research Center at Johns Hopkins Medicine and the study's corresponding author.
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Why outside experts still urge caution
The trial is unusual for its length and for its use of a real clinical outcome, a dementia diagnosis in Medicare records, rather than a short-term memory score.
Even so, brain-training research has a long history of underwhelming results, and outside experts noted that this is one study. Behavioral neurologist Andrew Budson told AARP that "it's really quite rare for any computerized-game brain training study to show positive results."
The commercial software used in ACTIVE has since evolved and is sold to consumers, but the researchers did not test the current retail versions.
Other work has linked simple lifestyle patterns, including walking speed and cognitive decline, to dementia risk in older adults, and public-health authorities continue to point to blood pressure control, hearing care and physical activity as the interventions with the strongest evidence.
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Anyone concerned about memory changes should raise it with their doctor rather than rely on a brain-training program.
In the ACTIVE trial itself, the schedule that produced the 25 percent reduction was clear: a short initial course of speed-of-processing training in the first six weeks, four booster sessions at the end of year one, and four more booster sessions at the three-year mark.
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This article is made and published by Jesper Bengtson, who may have used AI in the preparation.