Aperture viewing : A review and a synthesis

We argue that two processes are involved in the visual perception of shapes moving behind narrow apertures. “Retinal painting” occurs when the eyes are free to pursue the moving shape and when the traverse time across the aperture is sufficiently short to allow visual persistence of the temporally successive views. When pursuit eye movements do not occur, however, the shape may still be perceived if it moves relatively slowly. The latter kind of perception does not involve seeing all the parts of the shape simultaneously (as in the case with retinal painting) but we demonstrate that shapes seen in this way have some of the same properties as conventionally presented shapes. The discussion emphasises the relevance of these findings to general problems in movement perception.