Walsh & Hoyt: Physiology of Motion Perception in Honhuman Primates

Several areas in the primate brain respond to visual motion. The best-known is the middle temporal area. MT neurons are selective for both direction and speed, but not for shape or color. MT has two major projections: to MST and to the ventral intraparietal area (VIP). The ventral and dorsal regions of MST may be functionally distinct. Ventral MST responds best to the relative motion of small objects, whereas dorsal MST responds best when visual motion occurs over large portions of the visual field. Dorsal MST neurons also respond to large complex motion patterns, such as expanding or contracting radial patterns, and rotating or spiraling motion, which suggests a role in analyzing self-motion. VIP has not been extensively investigated, but it is known to have cells that are sensitive to moving stimuli.