Stereo-Curvature Aftereffect Is Due to More Than Shape Curvature Adaptation

Abstract

For stereo-curvature aftereffect (sCAE), there is no agreement on whether adaptation occurs at the disparity-specified stage, the percept-specified stage, or both. Additionally, it remains uncertain whether retinal-position-dependent sCAE can be induced by possible adaptation to disparity-specified sources. Our study aimed to investigate the dependency and processing levels of adaptation underlying sCAE using dynamic spherical adaptation stimuli with static fixation. Experiment I examined the dependency by dynamically altering the location or size of adaptation stimuli. Experiment 2 investigated the adaptation levels via three sub-experiments: Experiment 2.1 examined how eccentricity influenced adaptation strength using static adaptation stimuli with different eccentricities, Experiment 2.2 tested a hypothesis about adaptation to a percept-specified primitive shape index (PSI) using dynamic size change of adaptation stimuli, and Experiment 2.3 tested another hypothesis on adapting disparity-specified average disparity information (ADI) using dynamic PSI change of adaptation stimuli. The results showed retinal-position-dependent and scale-independent sCAE. In addition to a possible eccentricity effect, the retinal-position dependence can result from ADI adaptation while the scale independence can be attributed to PSI adaptation. Therefore, sCAE is caused by adaptation at both the disparity-specified and percept-specified stages. Additionally, sCAE endows two coexisting adaptation processes with one dependent on retinal position and one independent of retinal position.

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

“…These researchers concluded that the disparity per se, not the perceived depth, was adapted by the visual system. Yan and Shigemasu (2015) dynamically changed the location, size, and depth of spherical adaptation stimuli and found that both disparity- and percept-specified processes were involved in stereo-curvature adaptation.…”