Floating square illusion: Perceptual uncoupling of static and dynamic objects in motion

One of the primary goals of motion analysis is to accurately track the movement of objects in the environment. We report on a novel illusion in which two objects moving with identical physical velocities have different perceived velocities, creating an apparent offset in their relative spatial positions. The stimulus is a smaller object composed of a static noise pattern superimposed on a larger object composed of dynamic noise. When the two objects are moved, the smaller object appears to lag behind the larger object. In the present study, we report our observations on this novel effect. The results of our experiments indicate that the effect arises from differences in the perceived speed of static and dynamic patterns presented in the context of moving objects.