Direct projections from the ventral premotor cortex to the hindlimb region of the supplementary motor area in the macaque monkey.

A retrograde tracer, Diamidino yellow, was injected into the hindlimb region of the supplementary motor area after intracortical microstimulation mapping in the Japanese monkey. As a result, a cluster of retrogradely labeled neurons was found in the caudal bank of the arcuate sulcus, which corresponds to the ventral premotor cortex. The present findings suggest that there exists a hindlimb representation in the ventral premotor cortex.