STEREOSCOPIC MODULATION OF DA VINCI STEREOPSIS
The present study investigated how depth localization of unpaired monocular dots positioned close to a possible occluder (in so-called â€œda Vinciâ€ stereopsis) was affected by an adjacent stereoscopic plane. We systematically manipulated the relative depth of the stereoscopic plane (defined by a sparse random-dot stereogram) to the occluder and to which eye the unpaired dots were presented. The results showed that the depth of the unpaired dots was strongly affected by that of the stereoscopic plane and the former could be predicted by extrapolating the latter when both the relative depth and the presented eye were ecologically valid. However, when either of the two factors was invalid, the influence of stereoscopic depth was much reduced and the perceived depth of the dots became ambiguous. These results suggest that da Vinci stereopsis can be strongly modulated by stereoscopic processing and the modulation is partially regulated by occlusive relations.