Multiple Loci for Foveolar Vision in Macaque Monkey

Motivation: Foveolar vision (central 1º of vision) is important for many visual behaviors; however, its cortical representation is poorly understood. Goal(s): To understand the functional organization of foveolar visual cortex in macaque monkey. Approach: Use human 7T to conduct fMRI of foveal visual cortex at submillimeter resolution (0.6mm in-plane) in awake fixating macaque monkeys. Results: We found at least 8 distinct loci of foveolar representation per hemisphere, one each for dorsal and ventral V1/V2, V2/V3, V3/V4, V4/TEO. These loci surround a substantial cortical territory (the foveolar core) which lies outside topographic cortex. Impact: The foveolar core may represent a higher-order specialization for foveal behaviors.