Saccadic eye movements and visual stability

Abstract

WE rarely confuse motions of our retinal images that result from movements of objects with those that result from eye movements. A predominant explanation of the perceptual stability that survives saccadic eye movements is that visual information about image movement is weighed against an internal (‘extraretinal’) signal about eye movement, and that a mismatch is generally perceived as movement of the world¹. Accurate information about eye position, even during a saccade, seems to be available to the oculomotor system^2,3, but it is not clear that this information finds its way to mechanisms underlying perceptual stability. The experiments we describe here show that errors in localisation following saccades are matched closely by errors in the size of saccades. We infer from this that the perceptual system does not monitor the extent of a saccade but merely assumes that an intended eye movement was made correctly.