Vision during saccadic eye movements. I. Visual interactions in striate cortex

Abstract

Psychophysical experiments demonstrated that the brief stimulation during saccadic eye movement is masked by visual stimuli before and after the saccade. The physiological correlates of this masking effect were investigated by studying the response of single cells in the primary visual (striate) cortex of awake monkeys [Macaca mulatta] trained to fixate and make saccadic eye movements. All cells showed an attenuation of the response to visual stimulation during a saccade when the saccade was preceded by a stimulus falling on the receptive field of the cell. Stimuli falling on the receptive field following the saccade usually did not attenuate the response to stimulation during a saccade. Instead the responses to stimuli occuring during a saccade and after a saccade usually merged indistinguishably as though there were a single stimulus, with onset at the time of the stimulus during the saccade and offset at the time of offset of the post-saccadic stimulus. The stimulus interaction effects were more powerful than any input to striate cortex occurring as a corollary to generation of saccades (a central inhibition) or resulting from a suppression due to movement of stimuli in the peripheral visual field (a periphery or shift effect). The effect is powerful enough to be an important physiological mechanism underlying the lack of perception during sacchardic eye movements made in contoured environments.