Does symmetry structure facilitate the depth separation
between stereoscopically overlapped dot planes?

ABSTRACT

Direct and indirect methods were used in 3 experiments with a total of 4 adult observers to investigate the problem of whether a symmetrical structure can influence the discrimination of the depth separation of overlapped dot planes. In the direct method, 3 or 2 overlapped dot planes consisting of symmetrical or random dots were presented, with Ss were required to discriminate 3 overlapped from 2 overlapped planes. In the indirect method, Ss were required to discriminate the depth positions of a target dot (or a pair of dots) that disappeared during stimulus presentation. Discrimination performance improved and reached a perfect level in the direct method and a modest plateau level in the indirect method with increasing relative disparity between the 2 outer planes, irrespective of whether the dot pattern had a symmetrical structure. These results suggest that a detection process for symmetry structure on a 2-dimensional plane in 3-dimensional space will not have a direct or an indirect connection (e.g., via a feedback loop) to a process involved in the depth separation.

AUTHOR Ishiguchi, Akira; Yakushijin, Reiko

AFFILIATION Ochanomizu U, Dept of Human & Social Sciences, Tokyo, Japan

SOURCE Perception & Psychophysics. 1999 Jan Vol 61(1) 151-160