The nature of attention deficits in hemispatial neglect : an eye-tracking investigation

Objective: This study aimed to (a) define the temporal and spatial characteristics of attention in hemispatial neglect, differentiating between early- and late-stage deficits for egocentric and allocentric presentations, (b) use eye tracking in parallel with an intervention designed to re-allocate attention in neglect in order to determine the underlying eye movement changes that may result in improvement of neglect symptoms, and (c) use eye-tracking data from behavioural tasks to predict functional outcome for neglect patients. Method: Twenty-four patients with right-hemisphere stroke were administered neuropsychological assessment batteries and functional assessment. Neglect subtype was assessed using common behavioural measures of neglect in conjunction with eye tracking. Eye tracking was also used during a task designed to improve neglect symptoms. Results: Results indicate that behavioural assessments of neglect subtype can vary significantly in their diagnostic utility. In addition, data suggest that attention deficits in neglect may be more pronounced for sustained attention, and less for early, automatic attention. Data support the effectiveness of smooth-pursuit tasks in shifting attention toward the neglected hemispace for patients with egocentric neglect, while those with allocentric neglect may require more tailored interventions. Finally, results indicate differences in functional impairment between neglect subtypes, with combined ego- and allocentric neglect patients showing the poorest outcomes, and allocentric neglect patients showing worse functioning than those with egocentric or no neglect. Conclusion: Data collected in the current study have the potential to be used to further develop predictive models of functional outcome in the presence of hemispatial neglect. This preliminary, exploratory research serves as an important foundation for future research that may improve treatment for individuals suffering from neglect.Arts and Social Sciences, Irving K. Barber Faculty of (Okanagan)Psychology, Department of (Okanagan)Graduat