Mechanisms of perceptual learning of depth discrimination in random dot stereograms

Authors

Liat Gantz
Saumil S Patel
Susana T L Chung
Ronald S Harwerth

Publication Date

7-1-2007

Journal

Vision Research

Abstract

Perceptual learning is a training induced improvement in performance. Mechanisms underlying the perceptual learning of depth discrimination in dynamic random dot stereograms were examined by assessing stereothresholds as a function of decorrelation. The inflection point of the decorrelation function was defined as the level of decorrelation corresponding to 1.4 times the threshold when decorrelation is 0%. In general, stereothresholds increased with increasing decorrelation. Following training, stereothresholds and standard errors of measurement decreased systematically for all tested decorrelation values. Post training decorrelation functions were reduced by a multiplicative constant (approximately 5), exhibiting changes in stereothresholds without changes in the inflection points. Disparity energy model simulations indicate that a post-training reduction in neuronal noise can sufficiently account for the perceptual learning effects. In two subjects, learning effects were retained over a period of six months, which may have application for training stereo deficient subjects.

Keywords

Adult, Computer Graphics, Depth Perception, Discrimination Learning, Humans, Models, Psychological, Photic Stimulation, Psychometrics, Psychophysics, Reaction Time, Retina, Sensory Thresholds