Pinna’s Illusory Intertwining Effect

Estimation 9 December 2013 0 Comments

Pinna's illusory intertwining effect

This figure looks like a warped spiral made up of white and black squares on a gray background.  If you examine it more closely, however, you will find that it is actually made up of four concentric circles.  This illusion was first described by Baingio Pinna and Richard L Gregory in a 2002 article titled […]