Visual network activation in recovery from sensorimotor stroke

Recovery of finger movements after hemiparetic stroke has been shown to inv olve sensorimotor brain areas in perilesional and remote locations, Hand us e, however, critically depends on visual guidance in such patients with str oke lesions in the middle cerebral artery territory. Using regional cerebra l blood flow measurements, we wished to identify interrelated brain areas t hat are engaged in relation to manual activity in seven patients after thei r first hemiparetic brain infarction. During the blind-folded performance o f sequential finger movements, the patients differed significantly from hea lthy controls (n = 7) by the recruitment of a predominantly contralesional network involving visual cortical areas, prefrontal cortex, thalamus, hippo campus, and cerebellum. Greater expression of this cortical-subcortical net work correlated with a more severe sensorimotor deficit in the acute stage after stroke reflecting its role for post-stroke recovery. Patients also di ffered from controls on a lesion-related pattern expressed during rest. A t hird differentiating pattern involved the ipsilesional supplementary motor area and the contralesional premotor cortex. Our results suggest that post- stroke recovery from impaired sensorimotor integration utilizes crossmodal plasticity of a visual network.