Wednesday, October 24, 2007

Ishihara Test for Color Blindness

Color blindness, or color vision deficiency, in humans is the inability to perceive differences between some or all colors that other people can distinguish. It is most often of genetic nature, but may also occur because of eye, nerve, or brain damage, or due to exposure to certain chemicals.

Color blindness is usually classed as disability; however, in selected situations color blind people may have advantages over people with normal color vision. There are some studies which conclude that color blind individuals are better at penetrating certain camouflages.

What numbers do you see revealed in the patterns of dots below?

First Row: 25 (Left) 29 (Right); Second Row: 45 (Left) 56 (Right); Third Row: 6 (Left) 8 (Right)

The individual with normal color vision will see a 5 revealed in the dot pattern.
An individual with Red/Green (the most common) color blindness will see a 2 revealed in the dots.

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