MAPPING STRIATE AND EXTRASTRIATE VISUAL AREAS IN HUMAN CEREBRAL-CORTEX

Functional magnetic resonance imaging (fMRI) was used to identify and map the representation of the visual field in seven areas of human cer ebral cortex and to identify at least two additional visually responsi ve regions. The cortical locations of neurons responding to stimulatio n along the vertical or horizontal visual field meridia were charted o n three-dimensional models of the cortex and on unfolded maps of the c ortical surface, These maps were used to identify the borders among ar eas that would be topographically homologous to areas V1, V2, V3, VP, and parts of V3A and V4 of the macaque monkey, Visually responsive are as homologous to the middle temporal/medial superior temporal area com plex and unidentified parietal visual areas were also observed, The to pography of the visual areas identified thus far is consistent with th e organization in macaque monkeys, However, these and other findings s uggest that human and simian cortical organization may begin to differ in extrastriate cortex at, or beyond, V3A and V4.