Short-latency visual stabilization mechanisms that help to compensate for translational disturbances of gaze

Recent studies in primates have revealed short-latency visual tracking mechanisms that help to stabilize the eyes during translational disturbances of the observer, and so operate as backups to otolith-mediated vestibulo-ocular reflexes. One such mechanism generates version eye movements to help stabilize gaze when the moving observer looks off to one side, utilizing binocular disparity to help single out the images in the plane of fixation (ocular following). Two others generate vergence eye movements to help maintain binocular alignment on objects that lie ahead: one responds to the radial patterns of optic flow (radial-flow vergence) and the other to the changes in binocular parallax (disparity vergence). Accumulating evidence suggests that, despite their short latency, all are mediated by the medial superior temporal area of cortex.