Color Blindness (color vision deficiency)
Color blindness (color vision deficiency) is the decreased ability to see color or differences in color. Color blindness often happens when someone cannot distinguish between certain colors. This usually happens between greens and reds, and occasionally blues. It is a sex-linked inheritance found in human beings. It is a rather common trait and more common in males It is because the Y chromosome is inserted for this trait. Only one gene of this trait will render a color-blind man. While on the other hand, a woman must have two genes for this trait to become color blind
Types of color blindness
The most common type of color blindness makes it hard to tell the difference between red and green. Another type makes it hard to tell the difference between blue and yellow. People who are completely color blind don’t see color at all, but that’s not very common.
Red-green color blindness
The most common type of color blindness makes it hard to tell the difference between red and green.
There are 4 types of red-green color blindness:
- Deuteranomaly is the most common type of red-green color blindness. It makes the green look redder. This type is mild and doesn’t usually get in the way of normal activities.
- Protanomaly makes red look more green and less bright. This type is mild and usually doesn’t get in the way of normal activities.
- Protanopia and deuteranopia both make you unable to tell the difference between red and green at all.
Blue-yellow color blindness
This less-common type of color blindness makes it hard to tell the difference between blue and green, and between yellow and red.
There are 2 types of blue-yellow color blindness:
- Tritanomaly makes it hard to tell the difference between blue and green, and between yellow and red.
- Tritanopia makes you unable to tell the difference between blue and green, purple and red, and yellow and pink. It also makes colors look less bright.
Complete color blindness
If you have complete color blindness, you can’t see colors at all. This is also called monochromacy, and it’s quite uncommon. Depending on the type, you may also have trouble seeing clearly and you may be more sensitive to light
Causes of color blindness
In the retina, there are two types of cells that detect light. They are called rods and cones. Rods detect only light and dark and are very sensitive to low light levels. Cone cells detect color and are concentrated near the center of your vision. There are three types of cones that see color: red, green, and blue. The brain uses input from these cone cells to determine our color perception.
Color blindness can happen when one or more of the color cone cells are absent, not working, or detect a different color than normal. Severe color blindness occurs when all three cone cells are absent. Mild color blindness happens when all three cone cells are present but one cone cell does not work right. It detects a different color than normal.
Most color vision problems that occur later in life are a result of:
- disease
- trauma
- toxic effects from drugs
- metabolic disease, or
- vascular disease
Symptoms of color blindness
- The difference between colors
- How bright colors are
- Different shades of colors
Treatment of color blindness
There is no treatment for congenital color blindness. It usually does not cause any significant disability. However, there are special contact lenses and glasses that may help. Your ophthalmologist can treat acquired forms of color blindness. He or she will address the underlying condition or drug that caused the problem.
