Adaptive Computerized Working Memory Training in Patients With Mild Cognitive Impairment. A Randomized Double-Blind Active Controlled Trial

Abstract

Objective We investigated if a 5-week computerized adaptive working memory training program (Cogmed ® ) of 20 to 25 sessions would be effective in improving the working memory capacity and other neuropsychological functions compared to a non-adaptive working memory training program (active-controlled) in adult patients with mild cognitive impairment (MCI). Methods This randomized double-blinded active control trial included 68 individuals aged 43 to 88 years, 45 men and 23 women, who were diagnosed with MCI at four Memory clinics. The study sample was randomized by block randomization to either adaptive or non-adaptive computerized working memory training. All participants completed the training, and were assessed with a comprehensive neuropsychological test battery before the intervention, and at 1 and 4 months after training. Results Compared to the non-adaptive training group, the adaptive training group did not show significantly greater improvement on the main outcome of working memory performance at 1 and 4 months after training. Conclusion No difference were found between the two types of training on the primary outcome of working memory, or on secondary outcomes of cognitive function domains, in this sample of MCI patients. Hence, the hypothesis that the adaptive training program would lead to greater improvements compared to the non-adaptive training program was not supported. Within group analyses was not performed due to the stringent RCT design.

Working Memory Training in Amnestic and Non-amnestic Patients With Mild Cognitive Impairment: Preliminary Findings From Genotype Variants on Training Effects

“…In the non-adaptive version, the participants trained at a fixed low level of difficulty, with a span of three or fewer items per task. The training is described in detail elsewhere ( Flak et al, 2019 ). However, since we did not observe group differences in the two types of training, and we have a limited sample size, we combined the participants who had the two training types into one group for each of the MCI subtype groups.…”

“…For Digit span, California Verbal Learning Test-II and Verbal Fluency alterative versions of the tests were used at each time-point to minimize practice effects. In order to compare cognitive performance across the domains, Z -scores were calculated based on the group performance at baseline as described elsewhere ( Flak et al, 2019 ).…”

“…Since no group differences on the training effects were found at baseline between the non-adaptive and adaptive WMT groups ( Flak et al, 2019 ), the data from these two training groups were pooled and analyzed as one training group. The sample size and power calculations were based on the primary outcome of the Memory Aid study with differences in training gains between the adaptive and non-adaptive WMT as reported ( Flak et al, 2019 ). Imputation was performed for two datapoints, for one subject at 4-week post training, and another at 16 weeks post training, using ‘missForest’ in R.…”

Meta-Analysis on the Effectiveness of Virtual Reality Cognitive Training (VRCT) and Computer-Based Cognitive Training (CBCT) for Individuals with Mild Cognitive Impairment (MCI)

“…The mean age of eighteen studies was 75.63 years old and age range was from 43 to 91 years old. Specifically, from the study done by Flak et al (2019), age range was from 43 to 88 years old, with a mean age of 66 years old. Since our study interest is on individuals with MCI aged 65 or above, the study by Flak et al (2019) was included in this review as the mean age was above the required age [22].…”

“…The overall attrition rate of both VRCT and CBCT was satisfactory (all less than 20%), except the CBCT study done by Finn and McDonald (2012) recorded a 33% attrition rate. The attrition rate ranged from 0% [25] to 33% [15], though dropout rate was not specified in some studies [22,23,[26][27][28][29][30]. The primary reason for dropouts was mainly independent of the intervention, such as unrelated medical or personal issues [15,[31][32][33][34].…”