The wagon wheel illusion in movies and reality.

Purves, D; Paydarfar, J A; Andrews, T J · Proc Natl Acad Sci U S A · 1996

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Abstract

Wheels turning in the movies or in other forms of stroboscopic presentation often appear to be rotating backward. Remarkably, a similar illusion is also seen in continuous light. The occurrence of this perception in the absence of intermittent illumination suggests that we normally see motion, as in movies, by processing a series of visual episodes.

Medical subject headings