Spatial working memory deficits and their association with revisit errors during visual search in patients with left...

The present study examined whether a subset of patients with left unilateral neglect (USN) exhibited lower spatial than shape (non-spatial) working memory performance, and whether such performance was associated with revisit errors (repeated cancellations of previously marked lines) in line cancellation tasks. Participants were patients with left USN and healthy controls. Participants completed spatial and shape working memory tasks in which stimuli were presented near the right edge of the display to minimise the influence of rightward attentional bias, thereby enabling a more accurate assessment of working memory performance. In the spatial working memory task, participants were required to focus on the locations of stimuli, whereas in the shape working memory task, they were required to focus on the shapes of stimuli. Participants also completed line cancellation tasks under two conditions, one in which markings remained visible (visible task) and the other in which markings were invisible (invisible task), with the instruction to cancel each line only once. The results revealed that some patients showed lower performance on the spatial than on the shape working memory task, whereas no patients showed the opposite pattern. Patients made more revisit errors in the invisible than in the visible task. Moreover, spatial working memory performance was negatively correlated with the frequency of revisit errors. These findings suggest that, in a subset of patients with left USN, spatial working memory deficits may be related to revisit errors during visual search, although the results should be interpreted with caution given the limited sample size.