The corpus striatum
(striated body) is a compound structure consisting of the striatum
and the globus pallidus
The term has been used in a few different ways:
From lateral to medial, the corpus striatum is composed of the external capsule (white matter), the lentiform nucleus (gray matter), the internal capsule (white matter), and the caudate nucleus (gray matter). The alternating white and gray matter give it a striated appearance.
The corpus striatum has received its name from the striped appearance which a section of its anterior part presents, in consequence of diverging white fibers being mixed with the gray substance which forms its chief mass.
A part of the corpus striatum is imbedded in the white substance of the hemisphere, and is therefore external to the ventricle; it is termed the extraventricular portion, or the lenticular nucleus.
The remainder, however, projects into the ventricle, and is named the intraventricular portion, or the caudate nucleus.