A cognitive training program based on principles of brain plasticity: results from the Improvement in Memory with Plasticity-based Adaptive Cognitive Training (IMPACT) study

Abstract

Objectives: To investigate the efficacy of a novel brain plasticity-based computerized cognitive training program in older adults and to evaluate the effect on untrained measures of memory and attention and participant-reported outcomes.

Design: Multisite randomized controlled double-blind trial with two treatment groups.

Setting: Communities in northern and southern California and Minnesota.

Participants: Community-dwelling adults aged 65 and older (N=487) without a diagnosis of clinically significant cognitive impairment.

Intervention: Participants were randomized to receive a broadly-available brain plasticity-based computerized cognitive training program (intervention) or a novelty- and intensity-matched general cognitive stimulation program modeling treatment as usual (active control). Duration of training was 1 hour per day, 5 days per week, for 8 weeks, for a total of 40 hours.

Measurements: The primary outcome was a composite score calculated from six subtests of the Repeatable Battery for the Assessment of Neuropsychological Status that use the auditory modality (RBANS Auditory Memory/Attention). Secondary measures were derived from performance on the experimental program, standardized neuropsychological assessments of memory and attention, and participant-reported outcomes.

Results: RBANS Auditory Memory/Attention improvement was significantly greater (P=.02) in the experimental group (3.9 points, 95% confidence interval (CI)=2.7-5.1) than in the control group (1.8 points, 95% CI=0.6-3.0). Multiple secondary measures of memory and attention showed significantly greater improvements in the experimental group (word list total score, word list delayed recall, digits backwards, letter-number sequencing; P<.05), as did the participant-reported outcome measure (P=.001). No advantage for the experimental group was seen in narrative memory.

Conclusion: The experimental program improved generalized measures of memory and attention more than an active control program.

Conflict of interest statement

Conflict of Interest: The IMPACT Study was funded by Posit Science Corporation through research grants to Mayo Clinic Foundation and the University of Southern California. Patricia Housen received compensation from Posit Science for consulting services. Kristine Yaffe received compensation from Posit Science for consulting services and honoraria for speaking engagements. Ronald Ruff received compensation from Posit Science for consulting services. Henry W. Mahncke is an employee of and holds stock options in Posit Science Corporation, the developer of the experimental training program.

Figures

Figure 1

Flow of participants in Improvement in Memory with Plasticity-based Adaptive Cognitive Training Study.

Figure 2

Pretraining and posttraining estimated means with 95% confidence intervals in the intention-to-treat group. For each outcome measure, the P-value and Cohen d effect size estimate is from the training group (experimental treatment (ET) vs active control (AC)) × time interaction, corrected for the significantly different sex distribution between groups. In (A) Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and (B) overall memory, higher scores are better; in (C) processing speed and (D) Cognitive Self-Report Questionnaire-25 Total, lower scores are better.