Relying on the external world after stroke: Individual variability in compensation strategies in working memory use

Capacity tasks are often used to assess working memory after stroke. However, in daily activities, patients may rely on the outside world by (re)inspecting information as needed (i.e., offloading), a strategy that is also advocated in memory rehabilitation. While individuals may use offloading in everyday life to support memory, and choose to memorize only to a low or medium extent, capacity tasks do not allow for nor reflect this. To understand how stroke patients use their working memory when less-than-full-loading is allowed, we recorded eye-movements of patients (n = 15) and controls (n = 38) as an index of offloading. Both patients and controls avoided working memory loading and relied heavily on offloading. Strategies varied at the individual level, with a subset of patients showing excessive offloading. Interestingly, these patients were also those who showed abnormal capacity scores, but the reverse was not necessarily true. We conclude that low memory capacity is related to, but does not automatically lead to, offloading behaviour. Even when offloading was hampered, maintaining offloading was still more beneficial than switching to a memory-based strategy, supporting the adoption of external strategies in memory rehabilitation. The free-choice paradigm brings us a step closer to estimating working memory use in everyday life.