Interhemispheric Interactions Associated With Performance of Voluntary Movements in Patients With Stroke Motor Disability

Performance of accurate skilled movements relies on interhemispheric interactions between the two motor cortices. It has been proposed that abnormal interactions could contribute to the motor deficit that results from chronic hemispheric lesions after stroke. The purpose of this protocol is to identify changes in interhemispheric inhibitory interactions associated with performance of a motor task in patients with chronic hemispheric stroke. The overall hypothesis is that the cortical representation of the paretic hand receives abnormally high task-related interhemispheric inhibitory influence originated in the intact motor cortex in stroke patients relative to healthy volunteers. It is important to test this hypothesis, because if proven correct, it could lead to the development of novel neurorehabilitative strategies.