Abstract
We investigated physiological mechanisms of binocular space perception. According to the original "energy model" (3,5), a perceived depth of object should not depend on differences in luminance contrasts of its monocular images. The data obtained by different authors are contradictory(1,2,4,6-8). Reasons for these contradictions were addressed. Stimuli and procedure. The fixation cross was located on the cyclopean axis. At distance of 2 deg of arc above and below the cross, observers saw two Gabor patches (upper test T and lower matched M stimuli), whose disparities equaled 7 min of arc. They were located either on the Medial plane, or to the left or right at 2.5 deg of arc from it. Contrasts of dichoptically presented two monocular stimuli (M) equaled 0.5, whereas contrasts of stimuli (T) were changed randomly in proportion (1:3; 1:2; 1:1; 2:1; 3:1), but the perceived brightness of fused stimulus T equaled the brightness of M. The disparity of T was constant, whereas the disparity of M stimulus changed randomly from the initial value by a step of 20 sec of arc (±100). Observers had to determine whether T stimulus is perceived as being further or nearer than M. Results: The influence of contrast differences on the perceived depth of object was minimal or zero only when the stimulus (M) was located on the Medial plane. However, contrast differences affected the depth perception of object (M) when it was moved away from the ; this contradicts the "energy model". A vector model is proposed to explain these findings.
Meeting abstract presented at OSA Fall Vision 2012