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.

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.