title: Three-dimensional motion aftereffects reveal distinct direction-selective mechanisms for binocular processing of motion through depth.
abstract: Motion aftereffects are historically considered evidence for neuronal populations tuned to specific directions of motion. Despite a wealth of motion aftereffect studies investigating 2D (frontoparallel) motion mechanisms, there is a remarkable dearth of psychophysical evidence for neuronal populations selective for the direction of motion through depth (i.e., tuned to 3D motion). We compared the effects of prolonged viewing of unidirectional motion under dichoptic and monocular conditions and found large 3D motion aftereffects that could not be explained by simple inheritance of 2D monocular aftereffects. These results (1) demonstrate the existence of neurons tuned to 3D motion as distinct from monocular 2D mechanisms, (2) show that distinct 3D direction selectivity arises from both interocular velocity differences and changing disparities over time, and (3) provide a straightforward psychophysical tool for further probing 3D motion mechanisms.
authors.affiliation: Center for Perceptual Systems, Department of Psychology & Section of Neurobiology, The University of Texas at Austin, Austin, TX 78712-0189, USA. czuba@utexas.edu
authors.forename: Thaddeus B
authors.initials: TB
authors.lastname: Czuba
authors.forename: Bas
authors.initials: B
authors.lastname: Rokers
authors.forename: Kyle
authors.initials: K
authors.lastname: Guillet
authors.forename: Alexander C
authors.initials: AC
authors.lastname: Huk
authors.forename: Lawrence K
authors.initials: LK
authors.lastname: Cormack
mesh_terms: D000328:Adult; D003867:Depth Perception / Q000502:physiology*; D006801:Humans; D008875:Middle Aged; D009039:Motion Perception / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D015357:Vision Disparity; D015348:Vision, Binocular / Q000502:physiology*