Color Blindness - Topic Overview
What is color blindness?
Color blindness means that you have trouble seeing red, green, or blue or a mix of these colors. It's rare that a person sees no color at all.
Color blindness is also called a color vision problem.
A color vision problem can change your life. It may make it harder to learn and read, and you may not be able to have certain careers. But children and adults with color vision problems can learn to make up for their problems seeing color.
What causes color blindness?
Most color vision problems are inherited (genetic) and are present at birth.
People usually have three types of cone cells in the eye. Each type senses either red, green, or blue light. You see color when your cone cells sense different amounts of these three basic colors. The highest concentration of cone cells are found in the macula, which is the central part of the retina .
Inherited color blindness happens when you don't have one of these types of cone cells or they don't work right. You may not see one of these three basic colors, or you may see a different shade of that color or a different color. This type of color vision problem doesn't change over time.
A color vision problem isn't always inherited. In some cases, a person can have an acquired color vision problem. This can be caused by:
What are the symptoms?
The symptoms of color vision problems vary:
- You may be able to see some colors but not others. For instance, you may not be able to tell the difference between some reds and greens but can see blue and yellow easily.
- You may see many colors, so you may not know that you see color differently from others.
- You may only be able to see a few shades of color, while most people can see thousands of colors.
- In rare cases, some people see only black, white, and gray.