Inspecting the external world: Memory capacity, but not memory self-efficacy, predicts offloading in working memory

Individuals with memory impairments may need to rely often on the external world (i.e. offloading). By memorizing only a fraction of the items at hand, and repeatedly looking back to the remainder of items (i.e. inspecting), they can avoid frailty or effortful memory use. However, individuals with subjective concerns may also prefer to rely on the external world even though their capacity is intact. Crucially, capacity assessment fails to recognize offloading strategies, while inspection assessment may reveal how people choose to deploy memory in everyday life. To disentangle the relative contributions of memory capacity and memory self-efficacy to offloading behavior, we recruited 29 individuals who were referred to a memory clinic and 38 age-matched individuals. We assessed memory capacity using neuropsychological measures, and memory self-efficacy using questionnaires. Inspection behavior was assessed in a copy task that allowed participants to store information to their preferred load or to rely on the external world. Referred individuals had lower capacity scores and lower memory self-efficacy. They inspected as often as controls, but used longer inspections and performed worse. Across all subjects, memory capacity - but not memory self-efficacy - explained inspection frequency and duration, with higher capacity associated with fewer and shorter inspections. Capacity measures thus translate to how people choose to deploy their memory in tasks that do not force full capacity use. However, people generally avoided remembering more than two items per inspection, and thus avoided using their full capacity. Inspection behavior was not further explained by memory self-efficacy, suggesting that inspections are not a sensitive measure of constraints experienced in everyday life. Although we provide support for the predictive value of capacity tasks in tasks with more degrees of freedom, capacity tasks overlook offloading behavior that individuals may employ to avoid using their full memory capacity in everyday life.