Abstract

The wealth of literature concerning motion perception and possible mechanisms for motion detection¹ is hardly paralleled by electrophysiological data concerning motion sensitivity in the visual system, especially in higher mammals. Recently characteristic visually evoked potentials (VEPs) in man have been described that are elicited by the onset and offset of pattern motion.² We have used a subdural electrode array in an alert rhesus monkey to investigate the origins and nature of these VEPs. Our results can be summarized as follows: area 17 acts as the source for this activity; the foveal projection in area 17 shows little or no motion-specific activity; a variety of stimuli, created to mimic real motion, fails to elicit this type of EP; rather, local flicker contained in such stimuli seems to be responsible for the EP; and strong interactions exist between the two response types: each can be reduced considerably by stimulus contamination.

© 1985 Optical Society of America