Visual field map clusters in macaque extrastriate visual cortex.
The macaque visual cortex contains >30 different functional visual areas, yet surprisingly little is known about the underlying organizational principles that structure its components into a complete "visual" unit. A recent model of visual cortical organization in humans suggests that visual field maps are organized as clusters. Clusters minimize axonal connections between individual field maps that represent common visual percepts, with different clusters thought to carry out different functions. Experimental support for this hypothesis, however, is lacking in macaques, leaving open the question of whether it is unique to humans or a more general model for primate vision. Here we show, using high-resolution blood oxygen level-dependent functional magnetic resonance imaging data in the awake monkey at 7 T, that the middle temporal area (area MT/V5) and its neighbors are organized as a cluster with a common foveal representation and a circular eccentricity map. This novel view on the functional topography of area MT/V5 and satellites indicates that field map clusters are evolutionarily preserved and may be a fundamental organizational principle of the Old World primate visual cortex.
Kolster
Hauke
H
Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts 02129, USA.
Mandeville
Joseph B
JB
Arsenault
John T
JT
Ekstrom
Leeland B
LB
Wald
Lawrence L
LL
Vanduffel
Wim
W
D000818:Animals; D001931:Brain Mapping; D016000:Cluster Analysis; D007839:Functional Laterality; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008253:Macaca mulatta; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D010100:Oxygen / Q000097:blood; D010775:Photic Stimulation / Q000379:methods; D014793:Visual Cortex / Q000098:blood supply / Q000502:physiology*; D014794:Visual Fields / Q000502:physiology*; D014795:Visual Pathways / Q000098:blood supply / Q000502:physiology; D014796:Visual Perception / Q000502:physiology
D010100:Oxygen