Color blindness test

Color blindness test

color blind

Some people suffer from their inability to distinguish between colors. This is called color blindness. There are three types of color blindness. The inability to distinguish between red and green is the most common. The second type is the inability to distinguish between yellow And the third type is the inability to distinguish colors permanently.

John Dalton, the world’s first chemist, has published the first paper to study color blindness, which he was not able to distinguish between red and green. The state of color blindness was called Daltonism.

Color-blindness is more prevalent among men than among women. This is due to the fact that this is a gender-related trait. The gene carries the heterozygous lesion on the X chromosome, and because the man has one X chromosome, , And the woman has a chromosome (X) so the gene must inherit the infection from the mother and father to be infected with the disease.

Color blindness test

Color blindness is performed when a person is suspected of retinal damage or may not be able to distinguish colors. The most common type of color blindness test is called Ishihara. In this examination, a person is required to recognize a picture of a letter or a number of small points in close colors against a background of small dots in different colors. If the subject is able to identify all the images presented to him, without errors, it means that he does not suffer from color blindness, but if he can not determine the shape in the images presented to him, it means that he suffers from a problem in the cells of the cones Responsible for seeing colors, or it is color blind. It is worth mentioning that some websites provide computerized tests to diagnose color blindness.

Symptoms of color blindness

There are many symptoms of color blindness that vary from one person to another, including:

  • Ability to distinguish between some colors, without the ability to distinguish others.
  • Ability to see some color grades only.
  • The ability to see only three colors; the color is white, gray, and black only.
  • The ability to see many colors, the patient does not know that he has a problem seeing colors.

Causes of color blindness

Causes of color blindness include:

  • Genetics: The main cause of color blindness is the genetic factor.
  • There are three types of conical cells in the human eye, each of which is specialized in capturing one of the three basic colors: blue, red, and green. When one or more of these cones is damaged, the patient will find Difficulty in distinguishing between colors.
  • Some medications that affect the eye, such as:
    • Psychotropic drugs, such as chlorpromazine, thiuridazine.
    • TB drugs such as ethambutol.
  • Exposure to an eye injury, or eye health problems such as:
    • Diabetic retinopathy and macular degeneration are two diseases that cause retinal damage.
    • Glaucoma, which causes high eye pressure, which reduces the ability of the optic nerve to transmit signals from the eye to the brain, which affects the patient’s ability to distinguish between blue and yellow.
    • Cataract, or cataracts that reduces the transparency of the eye lens.
  • Leber’s hereditary optic neuropathy, which causes the patient to be unable to distinguish between green and red colors in particular.
  • Some diseases that affect the eye, such as:
  • Aging.
  • Exposure to some toxic chemicals such as styrene.

Effects of color blindness

Color blindness may affect people’s lives and limit their ability to deal with daily life. A child with undiagnosed chromatic blindness may be concerned that he can not read what is written with yellow chalk on a green background or when he tries to choose colors in drawing lessons , And may find that colorless dishes are less attractive, and therefore suffer from a lack of appetite. Adults may find it difficult to read coded information, such as charts, pie charts, clothing, or vegetables, and dealing with the signal is a real challenge.

Treatment of color blindness and coexistence with it

Color blindness can not be cured medically, and some color blind people may not discover that they see colors differently from most people until many years have passed. Most people with this condition can live with their health and ways to overcome the problem of non-discrimination Colors include:

  • Save the order of colors of objects that can not highlight their colors, such as saving the order of the colors of the light signal.
  • Use smart phone apps designed to help people with color blindness.
  • Inform school officials of color-blind children about the nature of the child’s problem, to choose the right colors for chalk and printed paper.
  • Leave the task of coordinating clothes for close people.
  • The use of special glasses or contact lenses improves the patient’s ability to distinguish between red and green by allowing some wavelengths of light to pass through the lens without others.
  • Use of red lenses reduces the sensitivity of people with total color blindness.
  • Using a device called “eyeborg”, the total color blind can translate colors into different sound waves.