Disparity- and velocity-based signals for three-dimensional motion perception in human MT+.
How does the primate visual system encode three-dimensional motion? The macaque middle temporal area (MT) and the human MT complex (MT+) have well-established sensitivity to two-dimensional frontoparallel motion and static disparity. However, evidence for sensitivity to three-dimensional motion has remained elusive. We found that human MT+ encodes two binocular cues to three-dimensional motion: changing disparities over time and interocular comparisons of retinal velocities. By varying important properties of moving dot displays, we distinguished these three-dimensional motion signals from their constituents, instantaneous binocular disparity and monocular retinal motion. An adaptation experiment confirmed direction selectivity for three-dimensional motion. Our results indicate that MT+ carries critical binocular signals for three-dimensional motion processing, revealing an important and previously overlooked role for this well-studied brain area.
Rokers
Bas
B
Neurobiology, Psychology, Center for Perceptual Systems, Institute for Neuroscience, and Imaging Research Center, The University of Texas at Austin, Austin, Texas, USA. rokers@mail.utexas.edu
Cormack
Lawrence K
LK
Huk
Alexander C
AC
D000328:Adult; D001931:Brain Mapping; D002560:Cerebrovascular Circulation / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009039:Motion Perception / Q000502:physiology*; D009483:Neuropsychological Tests; D009949:Orientation / Q000502:physiology*; D010775:Photic Stimulation; D012160:Retina / Q000502:physiology; D013028:Space Perception / Q000502:physiology; D013702:Temporal Lobe / Q000033:anatomy & histology / Q000502:physiology*; D015348:Vision, Binocular / Q000502:physiology*; D014793:Visual Cortex / Q000033:anatomy & histology / Q000502:physiology*; D014794:Visual Fields / Q000502:physiology; D014795:Visual Pathways / Q000502:physiology