A common assumption to maximise cognitive training outcomes is that training tasks should be adaptive, with difficulty adjusted to the individual’s performance. This has only been tested once in adults (von Bastian & Eschen, 2016). We aimed to examine children’s outcomes of working memory training using adaptive, self-select and stepwise approaches to setting the difficulty of training tasks compared to an active control condition.

In a randomised controlled trial (ACTRN 12621000990820), children in Grades 2-5 (7 to 11 years) were allocated to one of four conditions: adaptive working memory training, self-select working memory training, stepwise working memory training, or active control. An experimental intervention embedded in Minecraft was developed for teachers to deliver in the classroom over two weeks (10 x 20-minute sessions). The working memory training comprised two training tasks with processing demands similar to daily activities: backward span with digits and following instructions with objects. The control condition comprised creative building tasks. As part of a larger protocol, children completed at baseline and immediately post-intervention working memory measures similar to the training activities (primary outcome): backward span digits and letters versions, following instructions objects and letters versions. Primary analyses were intention-to-treat. Secondary analyses included only children who completed 10 sessions.

Of 204 children recruited into the study, 203 were randomised, with 95% retention at post-intervention. 76% of children completed all 10 training sessions. Comparisons between each working memory training condition and the active control on working memory measures were non-significant (f 2 = 0.00), with one exception. Children in the self-select condition on average performed 1-point better than the controls on the following instructions objects measure (p = .02, f2 = 0.03). A pattern emerged that the self-select condition performed better on most measures.

We found little evidence that an adaptive approach to setting the difficulty of training tasks maximises training outcomes for children. Findings suggest that working memory outcomes following training are limited and are not modulated by the approach to setting the difficulty of training tasks. This is consistent with findings from von Bastian & Eschen (2016), who also observed that the self-select condition (and not the adaptive condition) showed a slightly larger change in working memory performance following training than the control. It is helpful for clinicians to be aware that adaptive working memory training programs might not be superior in improving children’s working memory, and the benefits of programs are limited.