The effect of gaze angle and fixation distance on the responses of neurons in V1, V2, and V4.

What we see depends on where we look. This paper characterizes the modulatory effects of point of regard in three-dimensional space on responsiveness of visual cortical neurons in areas V1, V2, and V4. Such modulatory effects are both common, affecting 85% of cells, and strong, frequently producing changes of mean firing rate by a factor of 10. The prevalence of neurons in area V4 showing a preference for near distances may be indicative of the involvement of this area in close scrutiny during object recognition. We propose that eye-position signals can be exploited by visual cortex as classical conditioning stimuli, enabling the perceptual learning of systematic relationships between point of regard and the structure of the visual environment.