Stereospatial masking and aftereffect with normal and transformed random-dot patterns

Masking and aftereffect in the perception of binocular depth were studied using random-dot sterograms as adaptation and target stimuli. Detection of the target was impaired by prior adaptation only when the two stimuli differed in disparity by less than 2 minarc. The masking function was unaffected by uniocular enlargement and blurring within the adaptation stimulus, but masking was no longer selective to disparity when the elements seen by the two eyes were reversed in brightness. The stereoscopic depth aftereffect was also insensitive to uniocular enlargement and blurring, and could not be generated when there was brightness complementation within the adaptation stimulus. Both the masking and aftereffect data are interpreted as evidence that stereospatial detectors in human vision are insensitive to transforms that maintain luminance-spatial correlations in binocular input.