Mechanisms of perceptual learning of depth discrimination in random dot stereograms.
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.
Gantz
Liat
L
College of Optometry, University of Houston, 505 J. Davis Armistead Building, Houston, TX 77204-2020, USA.
Patel
Saumil S
SS
Chung
Susana T L
ST
Harwerth
Ronald S
RS
D000328:Adult; D003196:Computer Graphics; D003867:Depth Perception / Q000502:physiology*; D004193:Discrimination Learning; D006801:Humans; D008960:Models, Psychological; D010775:Photic Stimulation; D011594:Psychometrics; D011601:Psychophysics; D011930:Reaction Time; D012160:Retina / Q000502:physiology; D012684:Sensory Thresholds / Q000502:physiology*