The early effects of external and internal strategies on working memory updating training

Abstract

The mechanisms underlying working memory training remain unclear, but one possibility is that the typically limited transfer effects of this training reflect adoption of successful task-specific strategies. Our pre-registered randomized controlled trial (N = 116) studied the early effects of externally given vs. internally generated strategies in an updating task (n-back) over a 5-day period with a single 30-minute training session. Three groups were employed: n-back training with strategy instruction (n = 40), n-back training without strategy instruction (n = 37), and passive controls (n = 39). We found that both external and internal strategy use was associated with significantly higher posttest performance on the trained n-back task, and that training with n-back strategy instruction yielded positive transfer on untrained n-back tasks, resembling the transfer pattern typically seen after the ordinary uninstructed 4–6-week working memory training. In the uninstructed participants, the level of detail and type of internally generated n-back strategies at posttest was significantly related to their posttest n-back performance. Our results support the view that adoption of task-specific strategies plays an important role in working memory training outcomes, and that strategy-based effects are apparent right at the start of training.

Strategy mediation in working memory training in younger and older adults

“…Furthermore, the level of detail and type of self-generated N-back strategies reported by the uninstructed participants was significantly related to their post-test N-back performance. The results in Laine et al (2018) provided strong evidence for the Strategy Mediation Hypothesis, according to which strategy changes rather than increased WM capacity may underlie successful WM training outcomes ( Dunning & Holmes, 2014 ; Soveri et al, 2017 ).…”

“… Laine et al (2018) proposed and explicitly tested one aspect of this, the Strategy Mediation Hypothesis of WM training: that task-specific near-transfer gains are driven by developing and using a task-specific strategy during training. In younger adults, they used the N-back training paradigm ( Kirchner, 1958 ) in which participants see an ongoing string of individual stimuli (e.g., digits) stream on a computer screen.…”

“…They are asked to indicate whether each stimulus is identical to that presented n items back. Laine et al (2018) instructed some young adult participants to use a particular visualisation strategy during a single 30-min N-back training session. This strategy instruction resulted in significant improvement in the trained N-back task (with digits), and in two untrained N-back tasks using different stimuli (i.e., letters or colours), compared to participants who received no strategy instruction.…”

Training attention in children with acquired brain injury: a study protocol of a randomised controlled trial of the TALI attention training programme

“…For a power of 80%, a sample size of 40 is required to detect a large effect ( f =0.40) and a sample size of 98 for a medium effect ( f =0.25). Three previous cognitive training randomised controlled trials have reported medium to large effect sizes (eta-squared range 0.15–0.2744). Therefore, assuming an allocation ratio of 1:1, a sample between 40 and 98 participants should be sufficient to achieve adequate statistical power.…”

Training-induced improvement in working memory tasks results from switching to efficient strategies

“…We asked -what is it that participants learn which enables their substantial improvement in a challenging updating task designed to require limited-capacity online manipulations? The few recent studies that addressed this question suggest that the use of a task-specific strategy may facilitate training-induced improvement (Fellman et al, 2020;Laine, Fellman, Waris, & Nyman, 2018;Linares et al, 2019;. Indeed, the need for a strategy that reduces WM requirements has been gradually acknowledged (Redick, 2019).…”