20-Year Study: 5 Weeks of Speed-of-Processing Training Linked to Lower Dementia Hazard
A five-week cognitive training program may have long-term associations that extend decades later. In one of the longest follow-ups ever conducted in this field, researchers tracked older adults for 20 years after participating in a randomized clinical trial. The findings suggest that one specific type of brain training was associated with differences in dementia diagnoses over time. The results add rare long-term evidence to the scientific discussion around cognitive training and aging.
Note: This article is intended for general information and educational purposes. It summarizes scientific research in accessible language for a broad audience and is not an official scientific press release.
A new study published in Alzheimer’s & Dementia: Translational Research & Clinical Interventions (February 2026) examined whether cognitive training completed in late adulthood was associated with dementia diagnoses over a 20-year period.
The research was conducted by Norma B. Coe (Department of Medical Ethics and Health Policy, Perelman School of Medicine at the University of Pennsylvania; National Bureau of Economic Research), Katherine E. M. Miller (Johns Hopkins Bloomberg School of Public Health), Chuxuan Sun (University of Pennsylvania), Elizabeth Taggert (University of Pennsylvania), Alden L. Gross (Johns Hopkins Bloomberg School of Public Health), Richard N. Jones (Warren Alpert Medical School of Brown University), Cynthia Felix (University of Pittsburgh Graduate School of Public Health), Marilyn S. Albert (Johns Hopkins School of Medicine), George W. Rebok (Johns Hopkins Bloomberg School of Public Health), Michael Marsiske (University of Florida), Karlene K. Ball (University of Alabama at Birmingham), and Sherry L. Willis (University of Washington).
The study analyzed long-term outcomes from the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) randomized clinical trial. Researchers investigated whether different types of cognitive training were associated with later diagnoses of Alzheimer’s disease and related dementias (ADRD).
What the Researchers Investigated
The authors sought to determine the very long-term effect of cognitive training on the risk of Alzheimer’s disease and related dementias.
The original ACTIVE trial began in 1998–1999 and enrolled 2,802 community-dwelling adults aged 65 and older. Participants were randomly assigned to one of three cognitive training interventions or to a control group that received no training.
The three interventions focused on:
- Memory
- Reasoning
- Speed of processing
In this analysis, researchers examined up to 20 years of follow-up data to assess associations between training type, booster sessions, and diagnosed dementia.
How the Study Was Conducted
Participants in each training arm completed up to ten sessions lasting 60–75 minutes over five to six weeks.
Each intervention had a distinct focus:
- Speed-of-processing training involved computer-based visual search exercises. Participants were asked to identify visual details under increasingly shorter time limits while managing more complex information.
- Memory training focused on improving verbal episodic memory through structured instruction and practice using mnemonic strategies.
- Reasoning training focused on solving problems involving serial patterns and logical sequences.
Participants who completed at least eight of the ten initial sessions were eligible for additional booster training sessions. These booster sessions were delivered at 11 and 35 months after baseline and included up to four additional sessions each time.
For the 20-year follow-up analysis, researchers linked participant data to Medicare claims records from 1999 to 2019. Of the original 2,802 participants, 2,021 met criteria for inclusion in the claims-based analysis.
Dementia diagnoses were identified using the Chronic Conditions Warehouse (CCW) algorithm (a standardized Medicare method that identifies chronic conditions using International Classification of Diseases diagnostic codes).
Researchers used cause-specific Cox proportional hazard models (a statistical method used to estimate how different factors are associated with the timing of an event, such as a diagnosis) to examine associations between training type and dementia diagnosis over time. Analyses adjusted for baseline demographic and health factors.
What Makes This Study New
According to the authors, no prior cognitive training intervention has demonstrated associations with dementia diagnoses over a 20-year follow-up period.
Earlier publications from the ACTIVE study reported cognitive and functional outcomes up to 10 years. This new analysis extended the follow-up window to two decades and used Medicare claims data to capture diagnosed dementia outcomes independently from study-based cognitive testing.
The researchers also evaluated the role of booster sessions, which were part of the original trial design but had not previously been examined in relation to 20-year dementia outcomes.
Key Findings from the Study
Over 20 years, nearly half of the participants in the control group – 239 out of 491 people (48.7%) – were diagnosed with Alzheimer’s disease or related dementias (ADRD).
Researchers then compared this group to participants who received different types of cognitive training.
What did not show a difference
- Memory training was not associated with a statistically significant difference in dementia diagnoses compared to the control group.
- Reasoning training was not associated with a statistically significant difference.
- Speed-of-processing training without booster sessions was also not associated with a statistically significant difference.
What did show a difference
Participants in the speed-of-processing group who received additional follow-up training showed a statistically significant lower hazard of diagnosed ADRD compared to the control group.
The adjusted hazard ratio for this group was 0.75 (95% confidence interval: 0.59–0.95). This means that, over the 20-year follow-up period, their rate of diagnosed dementia was lower relative to participants who received no training.
Looking at the numbers more closely:
- 105 out of 264 participants (39.8%) in the speed + booster group (those who received additional speed-of-processing training sessions) were diagnosed with dementia.
- 239 out of 491 participants (48.7%) in the control group were diagnosed with dementia.
Among all three training approaches tested in the trial, speed-of-processing training combined with booster sessions was the only intervention that showed a statistically significant difference in dementia diagnoses over 20 years.
Why Dementia Prevention Matters
According to reporting by ScienceDaily, dementia involves a decline in thinking and memory severe enough to interfere with daily life and independent living. It is estimated to affect 42 percent of adults older than age 55 at some point in their lives and costs the United States more than 600 billion dollars annually. Alzheimer’s disease accounts for approximately 60 to 80 percent of cases, while vascular dementia represents about 5 to 10 percent. Other forms include Lewy body dementia, frontotemporal dementia, and mixed types.
“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, Ph.D., the corresponding study author and director of the Alzheimer’s Disease Research Center at Johns Hopkins Medicine, in comments reported by ScienceDaily. “Even small delays in the onset of dementia may have a large impact on public health and help reduce rising health care costs.”
Albert noted that further research is needed to better understand the biological mechanisms underlying these findings and to clarify why memory and reasoning training did not show the same long-term associations.
Authors’ Conclusions
The authors conclude that speed-of-processing cognitive training combined with booster sessions was associated with a lower hazard of diagnosed Alzheimer’s disease and related dementias over a 20-year follow-up period. They note that this association was observed only among participants who completed one or more booster sessions.
Memory training and reasoning training did not show statistically significant differences in diagnosed ADRD compared to the control group. Speed-of-processing training without booster sessions also did not show a statistically significant association.
The authors acknowledge several limitations. Dementia diagnoses were identified using Medicare claims data rather than clinical adjudication, which may affect diagnostic precision. Not all original participants were included in the Medicare linkage analysis, which could introduce selection bias. In addition, booster sessions were offered only to participants who completed most of the initial training sessions.
The researchers state that further studies are needed to better understand the mechanisms that may explain the observed association and to clarify why other types of cognitive training did not show similar long-term results.
Final Perspective
This 20-year follow-up of the ACTIVE randomized clinical trial provides rare long-term data examining how different forms of cognitive training relate to diagnosed dementia outcomes. Among the three interventions tested, only adaptive speed-of-processing training combined with booster sessions was associated with a statistically significant lower hazard of diagnosed ADRD.
The findings extend previous ACTIVE results by linking cognitive training data with Medicare claims records across two decades. While the results do not establish causation, they add to ongoing scientific research exploring how specific types of cognitive training may relate to long-term dementia diagnoses. Further investigation will be necessary to clarify underlying mechanisms and to confirm these associations in other populations.
The information in this article is provided for informational purposes only and is not medical advice. For medical advice, please consult your doctor.
Reference
Coe NB, Miller KEM, Sun C, Taggert E, Gross AL, Jones RN, Felix C, Albert MS, Rebok GW, Marsiske M, Ball KK, Willis SL. Impact of cognitive training on claims-based diagnosed dementia over 20 years: evidence from the ACTIVE study. Alzheimer’s & Dementia: Translational Research & Clinical Interventions. 2026;12:e70197. https://doi.org/10.1002/trc2.70197
