Abstract
Although depth adaptation has been widely studied by using disparity-defined surfaces, the level of adaptation still need to be clarified, especially for the disparity corrugated surface. To investigate whether multi-level processing is involved, we examined the phase- and orientation-independency of depth adaptation. Using dynamic random-dot stereograms, we tested the depth aftereffects of sinusoidal corrugations that were defined by horizontal-, vertical-oriented and combinations of these two orientations (plaids) in phase static and randomly changing conditions. In each condition, two adaptors with 20.2 arcmin and 4.1 arcmin amplitudes were presented at the left and right sides of the CRT monitor simultaneously for 6 s. The sides for the large and small adaptors were randomly counterbalanced. The test (12.1 arcmin) and comparison stimuli (in the range of 9.1 - 15.2 arcmin, nine levels) were also presented in the same way but only 0.5 s time duration. Participants were asked to judge which side had the larger amplitude and PSE was calculated. Also, using the same stimuli in phase changing condition, we tested the aftereffects that were adapted to horizontal-oriented corrugations, but probed by vertical-oriented corrugations, and vice versa. Although the results showed a little larger aftereffects in phase static condition which might be due to the retinotopic level adaptation, there were still obvious aftereffects in phase changing condition. These suggest the higher level phase-independent adaptation. The similar degree of aftereffects in phase changing condition induced by plaids stimuli as those by horizontal- or vertical-oriented corrugations was found, suggesting no interference of the combination with different-oriented sinusoidal corrugations. Moreover, the different-oriented adaptors and test probes caused the similar degree of aftereffects as the same orientation pairs. These results suggest the depth adaptation is orientation-independent, and it has a significant relationship with the peak-trough disparities of the adaptors, while not related to the retinotopic position.
Meeting abstract presented at VSS 2017