03D-04 Reversal of depth perception with interocular delay: psychophysics and model simulation
Satoko Yasuoka1, Seiji Tanabe1, Ichiro Fujita1
1Grad Sch of Frontier Biosciences, Osaka University, Toyonaka, Japan
To study the temporal fidelity of the neural system for stereopsis, a dynamic random-dot stereogram (RDS) was manipulated such that the dot pattern in one eye lagged behind that in the other eye. We examined effects of interocular delay on perceived depth of both binocularly correlated RDS (cRDS) and anticorrelated RDS (aRDS). Subjects reported whether a far or near plane was seen with respect to the surrounding plane. The depth percept of a cRDS degraded with an increase of interocular delay. At an intermediate delay (108 ms), the subjects perceived reversed depth. At all delays, the direction of perceived depth with an aRDS was inversed from the one with a cRDS. Simulation with a modified disparity energy model incorporating spatiotemporal filters showed that the disparity modulation of model neurons resembled psychophysical performance. Thus the reversal of perceived depth with interocular delays in both cRDS and aRDS is partially accounted for by processing units early in the stereoscopic system.