A neuronal correlate of spatial stability during periods of self-induced visual motion.

Motion of background visual images across the retina during slow tracking eye movements is usually not consciously perceived so long as the retinal image motion results entirely from the voluntary slow eye movement (otherwise the surround would appear to move during pursuit eye movements). To address the question of where in the brain such filtering might occur, the responses of cells in 3 visuo-cortical areas of macaque monkeys were compared when retinal image motion of background images was caused by object motion as opposed to a pursuit eye movement. While almost all cells in areas V4 and MT responded indiscriminately to retinal image motion arising from any source, most of those recorded in the dorsal zone of area MST (MSTd), as well as a smaller proportion in lateral MST (MST1), responded preferentially to externally-induced motion and only weakly or not at all to self-induced visual motion. Such cells preserve visuo-spatial stability during low-velocity voluntary eye movements and could contribute to the process of providing consistent spatial orientation regardless of whether the eyes are moving or stationary.