The Zeitraffer phenomenon, akinetopsia, and the visual perception of speed of motion: a case report.

The Zeitraffer phenomenon is the altered perception of the speed of moving objects. A single case is reported using the subject's own description of a transient alteration of the visual perception of motion. The literature on the subject is reviewed. The Zeitraffer phenomenon probably arises from dysfunction of brain networks subserving visual perception of speed. It shares characteristics with akinetopsia, the loss of visual ability to perceive motion.