Boundary conditions for observing cognitive load effects in visual working memory

When holding information in working memory, the proportion of time occupied by a concurrent task determines memory performance. This effect, the cognitive load effect, has been replicated many times. Recent work has referred to it as a law of cognition (Barrouillet, Portrat, & Camos, Psychological review, 118(2), 175-192, 2011) and a Priority-A Benchmark of working memory (Oberauer et al., Psychological bulletin, 144(9), 885-958, 2018), making it an important effect for all models of working memory to explain. Despite this, some recent work has demonstrated conditions under which this law does not apply, bringing into question its generalizability. The present work investigates the boundary conditions of the cognitive load effect in visual working memory. We show that only under specific circumstances is cognitive load crucial to visual working memory performance. Moreover, the data indicate that the theoretical underpinnings assumed to underlie the cognitive load effect, maintenance in the face of continued forgetting, may be incorrect, at least in visual working memory. We propose that cognitive load effects may reflect enrichment of the memory representation in low cognitive load task situations, not mitigation of ongoing forgetting.