3D shape discrimination using relative disparity derivatives.

Dawn Vreven

doi:10.1016/j.visres.2006.08.014

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3D shape discrimination using relative disparity derivatives.

Dawn Vreven

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Abstract

Three-dimensional (3D) shape discrimination could be achieved using relative disparity signals or it could be achieved using a higher-order disparity derivative detector. Two 3D shape discrimination tasks were used to distinguish between these possibilities: a within-shape task and a between-shape task. Disparity thresholds were larger when discriminating within the same shape than when discriminating between shapes. More importantly, within-shape discriminations were dependent on the pedestal disparity (distance from fixation) whereas between-shape discriminations were not. The results suggest that a mechanism sensitive to higher-order disparity derivatives can achieve discrimination between different 3D shapes.

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Discrimination, Psychological Fixation, Ocular Form Perception Humans Photic Stimulation Psychometrics Psychophysics Sensory Thresholds Size Perception Vision Disparity Vision, Binocular Journal Article Research Support, Non-U.S. Gov't

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Dawn Vreven. 2006-10-02. 3D shape discrimination using relative disparity derivatives.. https://doi.org/10.1016/j.visres.2006.08.014

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