Looking Dragon Optical Illusion

I just love this optical illusion - it freaked me out the first time I saw it, but once you know how it works it seems so simple.

Check out this video to see how it works, you\'ll be amazed. I\'ve actually made this illusion for myself using this template and it really does work.

http://www.grumbslinks.com/2008/07/looking-dragon-optical-illusion.html

Dragon Illusion Solved!

http://www.metacafe.com/watch/1278980/dragon_illusion_solved/

Hollow Face - Optical Illusions by Sir Richard Gregory

Will and Guy ponder how Celtic Druids used illusions at times like Halloween to impress and manipulate their worshipers.  We conjecture that witches could also manipulate ghostly images to frighten relatives of the dead.  The effect works because illusions prey on the brain.  Our central nervous system processes images in the present, but gets confused by pictorial memories of the past. 

In modern times, it was Hermann von Helmholtz, who first described illusions as unconscious inferences from sensory data and knowledge derived from an earlier time.  Von Helmholtz\'s discoveries have been developed by Sir Richard Gregory to create the illusion in the video below.

http://www.guy-sports.com/humor/halloween/ghost_optical_illusion.htm