Relationship of Depth Adaptation Between Disparity-Specified Plaids and Their Components

In the luminance domain, studies show that perceived contrasts of plaids are a nonlinear summation of their components. In the disparity domain, perceived depth has been studied by using a depth adaptation paradigm with simple surfaces; however, the relationship between depth adaptation between plaids and their components has not been investigated. To clarify this, combinations of disparity-defined horizontal corrugation (marked as horizontal) and disparity-defined plaids as adaptor-probe pairs were used. Three experiments were performed: The first two compared the aftereffects between horizontal-horizontal and plaid-horizontal pairs (Comparison 1) and between horizontal-plaid and plaid-plaid pairs (Comparison 2). Experiments 1 and 2 controlled the plaids to have the same and doubled peak-to-trough amplitudes as the horizontal corrugation, respectively. In Comparison 1, the horizontal or horizontally oriented component of the plaids was adapted. In Comparison 2, the plaid adaptor or horizontally oriented component of the plaid test stimuli was adapted. Thus, depth adaptation may be linked to cyclopean-oriented depth-from-disparity bandpass filters. The depth adaptation degree was determined by the adaptation of amplitudes of the similar oriented channels between the adaptation and test stimuli. Experiment 3 compared the aftereffects between noise-horizontal and horizontal-horizontal pairs. Since the noise adaptor contained multispatial frequency channels, only the channels with similar spatial frequencies as the horizontal corrugation were adapted, thus causing smaller depth aftereffects.