A1 Refereed original research article in a scientific journal
The role of strategy use in working memory training outcomes
Authors: Daniel Fellman, Jussi Jylkkä, Otto Waris, Anna Soveri, Liisa Ritakallio, Sarah Haga, Juha Salmi, Thomas J Nyman, Matti Laine
Publication year: 2020
Journal: Journal of Memory and Language
Article number: 104064
Volume: 110
Number of pages: 22
ISSN: 0749-596X
DOI: https://doi.org/10.1016/j.jml.2019.104064(external)
Cognitive mechanisms underlying the limited transfer effects of working memory (WM) training remain poorly understood. We tested in detail the Strategy Mediation hypothesis, according to which WM training generates task-specific strategies that facilitate performance on the trained task and its untrained variants. This large-scale pre-registered randomized controlled trial (n = 258) used a 4-week adaptive WM training with a single digit n-back task. Strategy use was probed with open-ended strategy reports. We employed a Strategy training group (n = 73) receiving external strategy instruction, a Traditional training group (n = 118) practicing without strategy instruction, and Passive controls (n = 67). Both training groups showed emerging transfer to untrained n-back task variants already at intermediate test after 3 training sessions, extending to all untrained n-back task variants at posttest after 12 training sessions. The Strategy training group outperformed the Traditional training group only at the beginning of training, indicating short-lived strategy manipulation effects. Importantly, in the Traditional training group, strategy evolvement modulated the gains in the trained and untrained n-back tasks, supporting the Strategy Mediation hypothesis. Our results concur with the view of WM training as cognitive skill learning.