A 65 years old woman with chronic high blood pressure and diabetes mellitus presented with a mutism akinetic of sudden onset and a right total hemiplegia with a Babinski sign secondary to a left anterior cerebral artery infarction. She had had six months earlier a transient gait disturbance. At that time, the CT scan showed lacunar infarcts of the head of both caudate nuclei. Neuropathological examination revealed that the left infarction of the anterior cerebral artery involved the superior frontal gyrus, the supplementary motor area, the cingulate gyrus and the corpus callosum. There were also multiple lacunes of the head of both caudate nuclei, anterior limb of the internal capsules, white matter, basal ganglia and thalami. The mutism akinetic was thought to be the result of a bilateral disruption of a functional loop including on each side, the supplementary motor area, the cingulate gyrus, the subcallosal tract and the head of the caudate nucleus. On the right side, the lesion of the caudate nucleus could have interrupted this loop normally involved in the induction of voluntary movements and in the communication with the external surroundings.