Fig. 2. Human visual cortex. Brodmann (1909) divided the human cortex into several different cytoarchitectonic areas. He designated striate cortex as area 17 and showed it as symmetrically surrounding the calcarine fissure on the mesial surface of the hemispheres. Simian area V1 is located more laterally (see Fig. 1). The foveal representation is located toward the occipital pole, while the peripheral visual field representations are located anteriorly, in the depths of the calcarine fissure. The parieto-occipital fissure is a fairly reliable anterior boundary for dorsal area 17. Extrastriate areas 18 and 19 concentrically surround area 17 and should correspond to the monkey's areas V2 and V3. Top. Ventral 18 and 19 (including the fusiform and lingual gyri) and adjacent temporal lobe areas contribute to a “what” pathway, which should contain regions corresponding to simian areas V4 (dark oval area) and IT. Bottom. Dorsal 18 and 19 extend onto the lateral surface of the hemisphere and contribute to a parietal or “where” pathway, which may contain a human homologue of the monkey's area MT (dark oval area) in portions of 19, 37, and 39.