Information processing for motor control in primate premotor cortex.

Recent neurophysiological as well as neuropsychological studies provided evidences on how various informations are processed to generate motor programs in the central nervous system. In this article, functional specializations of two distinct cortical motor areas, the dorsal and ventral aspects of the premotor cortex (PMd and PMv, respectively) of macaque monkeys, are focused to review this issue. Three major conclusions emerged from recent neurophysiological studies. First, each of movement parameters such as amplitude and direction is distinctively programmed in PMd by serial integration, rather than by parallel distributed processing. Second, in performance of conditional motor behavior, conditionally presented sensory signals are processed for motor preparation and execution of an intended act in PMd, but not in PMv. Third, PMv may be specialized for motor execution under visual guidance.