A COMMON MECHANISM FOR ILLUSORY AND OCCLUDED OBJECT COMPLETION

New phenomena and results are reported that implicate a common contour interpolation mechanism in illusory and occluded (modal and amodal) o bject completion. In 3 experiments, a speeded classification task was used to study novel quasimodal displays in which occluded and illusory contours join. Results showed the same advantages in speed and accura cy over control displays for quasimodal, illusory, and occluded displa ys. The implications of quasimodal displays, along with another new di splay type in which contour linkages must precede determination of mod al or amodal appearance, are considered. These logical considerations and empirical results suggest that amodal and modal completion depend on a common underlying mechanism that connects edges across gaps.