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Spatial limitation of vertical-size disparity processing.

H Kaneko·I P Howard
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Abstract

We investigated the upper limit of horizontal spatial modulation of vertical-size disparity in a textured surface for the perception of depth. In Experiment 1 subjects matched the appearance of a surface with modulated horizontal-size disparity to that of a surface with modulated vertical-size disparity. In Experiment 2 we determined the threshold amplitude of modulation of vertical-size disparity required for the perception of depth as a function of the spatial frequency of disparity modulation. The results indicate that sensations of depth are not elicited by modulations of vertical-size disparity of any amplitude at spatial frequencies higher than about 0.04 c/deg. We conclude that vertical disparities are averaged within about 20 deg-wide areas and suggest that this global measurement is used to scale local horizontal disparities for the perception of surface slant.

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Depth PerceptionHumansPhotic StimulationPsychophysicsSensory ThresholdsVision DisparityJournal ArticleResearch Support, Non-U.S. Gov't

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BibTeXRIS

H Kaneko, I P Howard. 1997. Spatial limitation of vertical-size disparity processing.. https://doi.org/10.1016/s0042-6989(97)00099-0

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