Unbelievable Bizarre Optical Illusion: What Do You See?

Wow,all you are to do is stare at the white dot at the centre of this negative of a woman's face. After about 15 seconds, glance at the white blank space to the right of the photo. The almost demonic figure transforms into the beautiful full-colour face of a young brunette woman. Did you see it?

This optical illusion is known as a 'negative afterimage' and is caused by cells located in the eyes, called ganglion cells, which send messages to the brain by coding – or identifying - colours in pairs of primary colours.