Branden T. Otte¹ (), Stephen H. Scott², Sean P. Dukelow³, Christopher L. Striemer^1,4; ¹MacEwan University, Edmonton, Alberta, Canada, ²Queen’s University, Kingston, Ontario, Canada, ³University of Calgary, Calgary, Alberta, Canada, ⁴University of Alberta, Edmonton, Alberta, Canada

Damage to the right temporal-parietal cortex often leads to spatial neglect – a disorder in which patients are unable to attend to people or objects on their contralesional (i.e., left) side. Previous research suggests that patients with spatial neglect may have impairments in spatial working memory (SWM). This has led some to suggest that a SWM deficit is a core component of the neglect syndrome that may exacerbate the severity of neglect symptoms. To further examine this hypothesis, 28 right hemisphere stroke patients (n=5 with spatial neglect) completed the Behavioural Inattention Test (BIT) – a standardized assessment for spatial neglect – as well as Spatial Span, Trails-A, and Paired-Associates Learning tasks using the Kinarm exoskeleton at baseline (median=31 days), and at ~2 months (n=21; median 65 days), and ~3 months (n=8; median=97 days) post-stroke. Our results demonstrate that, at each time point, patients with spatial neglect performed more poorly than patients without neglect on the Spatial Span task that measures SWM, as well as Trails-A, which measures visual search and visuomotor processing speed. In addition, at baseline, poorer performance on Spatial Span and Trails-A tasks were significantly correlated with the severity of spatial neglect symptoms (as measured by the BIT) across the entire patient group (n=28). More importantly, performance on the Spatial Span and Trails-A tasks at baseline were significant predictors of neglect symptom severity across the entire patient group at both the 2-month and 3-month follow-ups. Overall, these results provide further evidence that spatial neglect is accompanied by deficits in SWM and demonstrate, for the first time, that SWM deficits are associated with the severity of neglect symptoms over time.

Acknowledgements: This work was supported through a Natural Sciences and Engineering Research Council of Canada Discovery Grant awarded to C.L.S., an Ontario Research Foundation grant to S.H.S., as well as Canadian Institutes of Health Research and Heart and Stroke Foundation of Canada grants to S.P.D.