AKINETIC MUTISM - DISCONNECTION OF FRONTAL-SUBCORTICAL CIRCUITS

Akinetic mutism may result from anterior cingulate lesions or a discon nection of the limbic connections projecting from the cingulate throug h subcortical circuits, Based on nonhuman primate tracer studies, vent ral pallidal lesions should disrupt the anterior cingulate frontal-sub cortical circuit. A patient developed a rigid akinetic mute stare caus ed by bilateral lesions of the globus pallidus interna with ventral ex tension. The anatomic basis of the patient's clinical findings support a similarity in frontal-subcortical anatomy between humans and nonhum an primates, Isolated pallidal lesions are rare. Future studies should document whether ventral extension below the anterior commissure is a ssociated with a loss of motivation.