Motion-blur illusions.

The still-radii illusion, the figure-of-eight illusion, the band-of-heightened-intensity illusion and the dark-blurred-concentric-circles illusion have remained, until now, isolated relatively ill-explained phenomena. A single algorithmic model is proposed which explains these four visual illusions. In fact, this model predicts phenomena produced by motion of any gray-shaded patterns relative to the eyes (termed 'motion-blur illusions'). Results of a computer simulation of the model are presented. A novel instance of the proposed class of illusions, which can be readily experienced by the reader, is introduced to illustrate the generality of the model.