As you move your eyes around this image, the purple and yellow grapes appear to rotate around in circles.  Be careful with this one, you might start to get a little bit dizzy if you look at it for too long! To see more rotating circles, take a look back at the motion illusion in […]

Which way is this wheel on this old postcard turning?  Are you sure?  Stare at it for a little while and you might find that the direction the wheel is rotating in will change. If you stare up at a ceiling fan while it is spinning, you can replicate this strange effect. (via foto-jennic.com)

This illusion concerns apparent rotation generated by pure translation.  Square patterns consisting of four segments appear to rotate when they move straightly at a constant speed across the grid background.  More surprisingly, the rotations in opposite directions can be generated by exactly the same square patterns.  This illusion might be explained by the well-known inchworm […]