Corticostriatal projections from distal and proximal forelimb representations of the monkey primary motor cortex

Corticostriatal projections from one distal and two proximal subregions in the forelimb representation of the primary motor cortex (MI) were examined in the macaque monkey. The distal and proximal subregions in the anterior b ank of the central sulcus (distal and proximal-bank subregions) and the pro ximal subregion in the surface of the precentral gyrus (proximal-surface su bregion) of the MI were identified using intracortical microstimulation. Di fferent anterograde tracers were then injected into two of these three fore limb subregions of the MI. In the ipsilateral putamen, the distribution are as of corticostriatal fibers from the distal, proximal-bank and proximal-su rface subregions were arranged from ventrolateral to dorsomedial in this or der. These corticostriatal input zones were largely segregated from one ano ther. (C) 1999 Elsevier Science Ireland Ltd. Ail rights reserved.