Stereopsis activates V3A and caudal intraparietal areas in macaques and humans.
Stereopsis, the perception of depth from small differences between the images in the two eyes, provides a rich model for investigating the cortical construction of surfaces and space. Although disparity-tuned cells have been found in a large number of areas in macaque visual cortex, stereoscopic processing in these areas has never been systematically compared using the same stimuli and analysis methods. In order to examine the global architecture of stereoscopic processing in primate visual cortex, we studied fMRI activity in alert, fixating human and macaque subjects. In macaques, we found strongest activation to near/far compared to zero disparity in areas V3, V3A, and CIPS. In humans, we found strongest activation to the same stimuli in areas V3A, V7, the V4d topolog (V4d-topo), and a caudal parietal disparity region (CPDR). Thus, in both primate species a small cluster of areas at the parieto-occipital junction appears to be specialized for stereopsis.
Tsao
Doris Y
DY
Massachusetts General Hospital, NMR Center, Athinoula A. Martinos Center, Charlestown, Massachusetts 02129, USA. doris@nmr.mgh.harvard.edu
Vanduffel
Wim
W
Sasaki
Yuka
Y
Fize
Denis
D
Knutsen
Tamara A
TA
Mandeville
Joseph B
JB
Wald
Lawrence L
LL
Dale
Anders M
AM
Rosen
Bruce R
BR
Van Essen
David C
DC
Livingstone
Margaret S
MS
Orban
Guy A
GA
Tootell
Roger B H
RB
D000818:Animals; D001931:Brain Mapping / Q000379:methods*; D003867:Depth Perception / Q000502:physiology*; D006801:Humans; D008251:Macaca; D008297:Male; D010296:Parietal Lobe / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D014793:Visual Cortex / Q000502:physiology*