Perceptual completion in a dynamic scene: An investigation with an ambiguous motion paradigm

In this study we employed the streaming–bouncing stimulus to investigate aspects of dynamic occlusion, e.g., of objects that temporarily move under occlusion while covertly being tracked. Two occluders, both either luminance-defined or invisible (virtual), were placed on the trajectories of the moving objects in the streaming–bouncing stimulus. We found that the bouncing percept was dominant when the objects moved under luminance-defined occluders but not when they moved under virtual occluders. Perceived motion direction thus varied with occluder visibility. The results seem to suggest that perceptual completion of a moving object interferes with constant motion processing of the same object.