Occlusion improves the interpolation of sampled motion

Several studies show that the perception of occlusion may affect various aspects of motion perception. Here we present data indicating that occlusion cues also influence the visual interpolation of sampled motion. Normally, sampled motion stimuli are perceived as less smooth and jerkier when the spatial gaps between successive presentations of the "moving" target stimulus increase. Adding surfaces occluding the spatial gaps, however, we found that the perceived smoothness of motion was not only better, but also independent of the gap width. We argue that this effect occurs because the visual system attributes the interruptions in the motion path to occlusion rather than to the moving object itself.