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.