Grey matter near the base of the cerebral hemispheres, consisting of the corpus striatum (caudate nucleus and lenticular nucleus [globus pallidus and putamen]), claustrum, and amygdaloid nucleus. The basal ganglia are involved in the subconscious regulation of voluntary movement, and disorders in this region cause dyskinesias.
A mass of gray matter beneath the third ventricle consisting of the caudate, lentiform, and amygdaloid nuclei and the claustrum.