Cortico-striatal evoked potentials in the monkey (Macaca mulatta)

A systematic study has been made of topographic organization in the striatum of evoked potentials elicited by stimulation of the cerebral cortex in unanesthetized, comatose monkeys (Macaca mulatta). Stimulation of the dorsal field of the prefrontal convexity elicited potentials primarily in rostral portions of the caudate, while stimulation of the ventral field of the prefrontal convexity elicited potentials in ventromedial areas of the putamen. Stimulation of different points on the precentral and postcentral gyri revealed a distinct somatopic organization of evoked responses in the putamen, although responsive zones in the putamen to precentral and postcentral stimulation showed almost total overlap. An overlap of responsive zones to stimulation of the dorsal prefrontal convexity and the premotor area (area 6) was found in the dorsolateral part of the rostral caudate, while a zone of overlap of responses to stimulation of the ventral prefrontal convexity and "hand" motor area of the precentral gyrus was found in the ventromedial area of the putamen near the commissural level.