Colorblindness at a Glance
February 26, 2022
To see colors, our eyes have three types of “cone cells”: red, green, and blue. Colorblindness occurs when these cells are damaged, malformed, or are not read correctly by the brain. When one of these three colors is missing, it affects eyesight on a whole. For example, some people with colorblindness mix up the colors red and green, as they look the same to them–this is an indication of protanopia (damage to red cones), deuteranopia (damage to green cones), or tritanopia (damage to the blue cones). Some people even only see the world in one color because they only have one kind of cone (monochromia) or lack all pigment in their cones and see no color at all (achromatopsia).
Colorblindness can also occur from tetrachromacy, a condition that happens in 12% of women where a fourth type of light-absorbing cone is found in the eye; this gives these women “super color vision” that allows them to see more colors and tones than the rest of the human population. This expansion of colors is considered a type of colorblindness as these women similarly do not see color the same way as the average person.
Colorblindness is often the result of a genetic condition and is present with a person from birth. This is why so many people do not know they are colorblind–the different shades they see are normal for them as they cannot know the difference that the average eye sees. While most people who suffer from colorblindness are born with the condition, colorblindness may also develop because of age. For example, more blue-yellow blindness is more likely to happen with aging. Other colorblindness may develop from alcohol consumption affecting the health of the eyes.