Causes, Types And Treatment Of Color Blindness
Color blindness is a disorder that is almost always inherited and affects more men than women. In its most severe form, it means that the person can only see in black and white.
Color blindness is a visual disorder that makes it difficult or impossible to distinguish colors. The degree of concern varies greatly. Sometimes it is only difficult to distinguish between some red, green, yellow or blue tones; however, in the most severe cases, the person cannot distinguish colors.
This condition is related to an abnormality in the eye’s photoreceptor cells called rods and cones . These work in combination and are connected to the brain centers via the optic nerve. When these cells are defective, they cannot produce the image of the pigments and color blindness occurs.
What are the causes of color blindness?
The perception of color takes place in the retina, since this is where the cones and rods are located. The latter recognize white, black and the entire gray scale. The cones are sensitive to red, blue, and green. The interaction of these two types of cells enables humans to properly perceive the different colors and their shades.
Color blindness occurs when the rods, cones, or both have an abnormality or are absent. The causes for this are hereditary, brought about by the action of drugs or caused by an illness. Here we take a closer look at all of this.
Inheritance
The majority of color blindness cases are hereditary. Most often it happens that the mother passes them on to her child and does not cause any other type of visual defect. Although women carry the defective chromosome that causes the disease, men are more likely to inherit it.
Medication
There are various drugs that can cause color vision disorders. Some antipsychotics, such as chlorpromazine and thioridazine, cause color blindness in certain cases.
The antibiotic called ethambutol, which is used to treat tuberculosis, can also change the visual perception of colors. The doctor should take these undesirable side effects into account when prescribing the drugs mentioned.
Diseases
There are several eye diseases that can lead to color blindness. For example, glaucoma sometimes damages the optic nerve and can reduce the ability to distinguish colors or shades. In addition, macular degeneration as well as diabetic retinopathy destroy the retina and cause the same problem.
In cataracts, color perception is not lost, but it can be significantly reduced. In addition, other diseases such as diabetes, multiple sclerosis, Alzheimer’s or Parkinson’s can also cause color blindness.
Other factors
Research has found that aging can lead to impaired color vision in some people. Exposure to toxic chemicals such as styrene, which is found in some plastics, has also been linked to a loss of the ability to differentiate colors.
Types of color blindness
An initial classification of the types of color blindness is made based on the cause that causes it. This approach gives rise to two categories: inherited or acquired. In the first variant, it is passed on from parents to children, and in the second, other factors are the cause.
The different types of color blindness can also be classified according to the type of color perception disorder. This gives rise to four forms: anomalous trichromatism, achromatism, monochrome, and dichromatism. Now let’s look at each and every one of them.
Abnormal trichrome
The affected person does have cones in the retina, but these are defective and cause them to mix up colors. This is the most common form of color blindness; it can appear in three ways:
- Protanomaly: Difficulty perceiving red light
- Deuteranomaly: Failure to perceive green light
- Tritanomaly: Difficulty perceiving blue light
Achromatism
These are the cases when the person can only see black and white, including shades of gray. It occurs because the person has no cones in the retina or is suffering from neurological damage. It is a very rare condition that affects only 1 in 100,000 people.
Monochrome
Monochrome is also known as complete color blindness . With this type of color blindness, too, the view is given in black and white with a gray area. There are cones in the retina, but two of the three pigments that must be present in these cells are missing. It only affects a very small number of people.
Dichromasy
This is a form of color blindness that is classified as moderate and in which one of the three types of light is imperceptible. As with abnormal trichrome, there are three types.
Protanopia (red blindness)
In this form, there are no red photoreceptors on the retina. This leads to poor color perception at very long wavelengths. People see these tones as if they were cream or gray. This is the most common form of dichromacy.
Deuteranopia (green blindness)
In this case , the retina’s green photoreceptors are completely absent. It is difficult for those affected to perceive colors in the medium wave range. A weaker form of this is the deuteranomaly, the green weakness.
Tritanopia
This is the rarest form of color blindness and it completely lacks the retinal photoreceptors for the color blue. The person has difficulty perceiving colors with short wavelengths. Also, she sees yellow as if it were pink.
Treating color blindness and ways to improve people’s quality of life
There is currently no treatment for hereditary color blindness. If the disease is caused by drugs, other conditions, or exposure to toxic chemicals, it is appropriate to eliminate the causative factor.
Color filters on glasses or special contact lenses can help to better distinguish colors, but they do not correct the problem. In the future, gene replacement techniques may become available that may completely solve this problem.
There are some techniques and actions that color blind people can take to overcome the limitations the disorder is causing. For example, they can memorize the order of the colors at a traffic light so that they can correctly interpret the signal to stop or drive on.
You can also mark objects of a certain color so that they can be combined with other things and color-coordinated. There are currently computer applications that help distinguish colors.