The Spinning Dancer illusion is an optical illusion resembling a female dancer spinning around in circles on one foot. When you first view this image, you will either see the figure spinning in a clockwise or counterclockwise direction. If you watch the image rotate long enough, you may see the dancer suddenly start spinning in the opposite direction. How can the dancer appear to spin one way and then the other? The illusion derives from an inherent ambiguity from the lack of visual cues for depth.
Which way do you see her spinning initially? If you watch long enough, can you get her to start spinning in the opposite direction?