The proposed research will investigate two central problems in the study of unilateral spatial neglect, a common disorder in patients with stroke: a) whether neglect is a modality specific or polymodal disorder and b) the role of three factors - sensory inattention, directional hypokinesis and overactive orienting to the unneglected side - in the performance of neglect patients. Analysis of these problems may lead to a fuller understanding of neglect and its brain mechanisms, as well as to more effective treatment of the disorder. The first problem will be investigated by testing neglect patients and their controls for cross-modal spatial shifts of attention (Exp. IIA), and for visual and tactile-kinesthetic neglect in a rod-bisection task (Exp. IIB) and in a search task (Exp. IIC). With regard to the second set of problems, neglect patients will be tested for eye movements toward and away from visual targets (Exp. I) to better understand the role of sensory inattention and directional hypokinesis in neglect. The eye movements of neglect patients also will be recorded under conditions that permit an assessment of the role of deficient orienting to the neglected side and overactive orienting to the unneglected side (Exp. III). Another experiment (IVA) will evaluate the effect on visual search of dynamic visual stimuli presented on the neglected side, a procedure that may enhance orientation to that side. The effect on neglect of this procedure, along with patching the eye ipsilateral to the lesion (which is intended to reduce orientation to the unneglected side), will assessed separately and in combination (Exp. IVB). The last two experiments will use procedures that may be useful in the treatment of neglect.
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| Butter, C M; Kirsch, N (1995) Effect of lateralized kinetic visual cues on visual search in patients with unilateral spatial neglect. J Clin Exp Neuropsychol 17:856-67 |
