Keep in mind that this is a static image. It is not animated in any way. However, as your vision moves back and forth, the middle area will seem to move towards the centre (contracting) and the outer edges will seem to be move away (expanding) from the centre. Also worth noting - if you fixate on a point in the centre and not move your eyes this anomalous motion will stop. Sea Sickness
(Update: the web seems to have named this"The Purple Nurple Optical Illusion")
Walter Anthony(c)2007
(Update: the web seems to have named this"The Purple Nurple Optical Illusion")
Walter Anthony(c)2007
