ANATOMICAL EVIDENCE FOR MT AND ADDITIONAL CORTICAL VISUAL AREAS IN HUMANS

We stained human visual cortex for myelin, cytochrome oxidase, and the monoclonal antibody CAT-301 in an attempt to demonstrate and map MT ( V5) and other visual cortical areas in humans. Both flattened and unfl attened cortical tissue was examined. A likely candidate for area MT ( V5), which we refer to as MT, was demonstrated using all three stains. Myelin and CAT-301 labels for MT were demonstrated to be coincident b y comparing results from the two stains in adjacent sections. In all t hree stains, MT was an oval area approximately 1.2 x 2.0 cm, located 5 -6 cm anterior and dorsal to the foveal V1-V2 border. The position and size of MT as defined by the present anatomy are consistent with MT ( V5) as defined by functional measures in humans. In addition, flattene d cortical tissue stained for cytochrome oxidase revealed a distinctiv e staining topography in several cortical areas, including areas V1, V 2, MT, PX, and VX. Similar studies in flattened cortex of macaque and green monkeys demonstrated distinctive dark cytochrome oxidase stainin g in MT, PX, MTc, and V3.