Systematic perceptual distortion of 3D slant by disconjugate eye movements

When an observer pursues an object moving away from him or her, both eyes rotate in the opposite direction, and this type of disconjugate eye movement can generate eye movement-induced disparities in the case of dynamic objects that are present around the pursuit object. Such disparities are not usually generated by conjugate eye movement. The aim of this study was to determine whether eye movement-induced disparities could be calibrated with eye position information. Observers were requested to judge the slant of an object defined by the spatiotemporal pattern of occlusion during disconjugate eye movement. Interestingly, the observers’ perception of the slant of the target object was systematically distorted, although the perceptual distortion decreased somewhat in the presence of a salient reference around the target. This suggests that eye movement-induced disparities are not calibrated properly with eye position information.