第30回日本神経科学大会(横浜)
平成19年9月10日〜12日

発表日時:9月11日(火)13:00-14:00
抄録番号:11233

Depth discrimination for transient and sustained images by the human stereoscopic system
ヒト両眼視システムによる、パターン変化の速い像と遅い像に対する奥行き弁別

Maki Takano, Takahiro Doi, Ichiro Fujita
Frontier Biosciences, Osaka University, Toyonaka, Japan

A few psychophysical studies propose that stereoscopic depth is processed by different mechanisms, depending on the temporal properties of visual inputs. We tested this hypothesis by considering the recent physiological findings that neurons in the dorsal and ventral pathways compute the disparity energy and the global-match solution to the stereo correspondence problem, respectively. Subjects discriminated the depth of dynamic random-dot stereograms (RDSs). The pattern refresh rate of RDSs was varied across blocks of trials. In a single block, we varied disparity sign and the ratio between binocularly correlated and anti-correlated dots. At a fast refresh rate (e.g., 43 Hz), subjects perceived reversed depth for anti-correlated RDSs (aRDSs), and no depth when the two groups of dots balanced. At a slow refresh rate (e.g., 5 Hz), the reversed depth for aRDSs was weak, and correct depth was perceived at the balanced point. These results suggest that the disparity-energy and binocular-matching computations underlie stereopsis for transient and sustained visual inputs, respectively.