Mapping striate and extrastriate visual areas in human cerebral cortex.

TLDR

The study used fMRI to map visual field representations in seven cortical areas and to locate at least two additional visually responsive regions. Neuronal responses to vertical and horizontal visual field stimulation were mapped onto 3‑D cortical models and unfolded surface maps to delineate borders of areas homologous to V1–V4 and parts of V3A and V4. The study identified MT/MT+–like and parietal visual areas, found that the visual area topography matches macaque organization, but noted potential differences emerging beyond V3A and V4.

Abstract

Functional magnetic resonance imaging (fMRI) was used to identify and map the representation of the visual field in seven areas of human cerebral cortex and to identify at least two additional visually responsive regions. The cortical locations of neurons responding to stimulation along the vertical or horizontal visual field meridia were charted on three-dimensional models of the cortex and on unfolded maps of the cortical surface. These maps were used to identify the borders among areas that would be topographically homologous to areas V1, V2, V3, VP, and parts of V3A and V4 of the macaque monkey. Visually responsive areas homologous to the middle temporal/medial superior temporal area complex and unidentified parietal visual areas were also observed. The topography of the visual areas identified thus far is consistent with the organization in macaque monkeys. However, these and other findings suggest that human and simian cortical organization may begin to differ in extrastriate cortex at, or beyond, V3A and V4.