1.Stare at the red dot on this woman's nose for thirty seconds. 2. Then, look over at a blank white space. (after you do it the first time, repeat the process and just close your eyes). 3. You will see the actual version of this beautiful woman.
The Scientific Explanation: When you stare long enough at an object, the eye's photoreceptors lose sensitivity from overstimulation (more exact- the color-sensitive cone cells) . When you divert the eyes to a blank space, the surrounding cone cells send out a much stronger signal. The brain then interprets this discrepancy as looking at the precise opposite colors, in what is known as a "negative afterimage".