[Involuntary motor activity or alien hand syndrome following ischemic lesion sparing medial frontal cortex].

We report a case of a left alien hand syndrome without grasp reflex, inter-manual conflict or sensory impairement after an infarction involving the striatum, premotor lateral cortex and colossal fibers but sparing medical premotor cortex. According to the location of the lesion, the mechanism underlying this clinical feature might mainly involve cortico-putamino-thalamo-cortical loop which links extrapyramidal system to medial premotor cortex.