Color perception or color perception is the ability of a person to perceive and transform light radiation of a certain spectrum with his vision. There are a number of deviations in people in color perception. One of the most common anomalies is protanopia. This is a visual defect in which a person does not distinguish between red and its shades.
Historical reference
The first person to talk about visual anomalies was the chemist and natural scientist John Dalton. He also described this disease in 1794. He did not make his observations out of idle interest, but because he himself suffered from protanopia. Now all diseases of a hereditary nature associated with color perception abnormalities are called color blindness.
Color blindness and its forms
Color blindness is the inability to distinguish one of the three primary colors. Therefore, three types of disease are distinguished: protanopia, deuteranopia, and tritanopia. Monochromasia or color blindness (full) is also highlighted - this is the perception of the whole world in black and white.
The latter type of pathology is found only in 0.00003% of the population on the entire planet.
These species only characterize the degree of color blindness, and the symptoms themselves are weak.
The clinical picture and diagnosis of protanopia
The disease is quite rare and is more common in men (8%) than in women (0.5%). It is believed that people with such a pathology are no more than 1% on the entire planet.
The first problem a person faces with protanopia is the inability to distinguish between red and its shades. To refute and confirm the diagnosis, a series of studies and tests are carried out. The most popular test is the Rabkin table. This option involves the presentation of several plates or sheets on which numbers and figures are applied in different shades. If a person is healthy, then he quickly recognizes the numbers, letters or other characters on the plate.
You can observe how a child chooses candy in candy wrappers. The kid should be offered a choice of sweets in multi-colored wrappers, and offered to choose the sweetness of a particular color. If there are problems, then the child will take candies at random.
Diagnosis in children
To determine if a child has color deviations, you can simply look at his drawings. If the painted images are painted in uncharacteristic colors, then this is the first bell, although you should talk with the child, perhaps he has only a big fantasy.
Work mechanism
Trichomasia is a normal state of the visual organ in which a person perfectly distinguishes all colors. The mechanism of the eye is that it has two different types of cells that are responsible for color sensation:
- sticks that allow you to distinguish colors in the dark;
- cones to distinguish between colors during the day.
An anomaly develops if some basic pigment disappears, and then the cells of the eye lose the ability to transmit shades normally.
Causes of occurrence
Protanopia is a genetic anomaly, as, indeed, are all other defects in color perception. In most cases, a genetic defect is transmitted through the male line, it is very rare in women. This is due to the fact that the anomaly is encoded in the X chromosome, and it is represented in the male body in the amount of 1 piece. A woman has two such chromosomes, therefore, anomalies practically do not occur.
For the woman to develop the disease, 2 conditions must be met: the father must have protanopia, and the mother must have a mutated gene. Only in this case can a girl develop a disease, although with a probability of about 1 in 1 000 000. The risk of a disease increases only in families where marriages between close relatives are allowed.
Very rarely, but still there are cases when the pathology appears under the influence of external factors. Perhaps the development of protanopia against a background of cataracts, while the last stage may be characterized by a complete inability to distinguish colors.
A problem can occur against the background of an eye injury or due to prolonged exposure to chemical compounds on the body, for example, taking medications or working in a chemical plant.
There is a possibility of becoming a color blind protanopic if a serious infectious or viral disease, heart attack or stroke is suffered.
Against the background of age-related macular degeneration and diabetic retinopathy, this pathology may also appear.
Long-term exposure to ultraviolet rays on the retina leads to the development of many pathologies, including non-perception of red color.
Difference in perception
With color blindness, a person does not see one or two colors. About the fact that color blind people confuse green with red is a real myth. In fact, protanopia is the inability to determine red, deuteranopia is green, and tritanopia is blue. As a result, the human brain, unable to determine any color or two, simply replaces it with another. In fact, the anomaly is not even a disease, people see everything, but perceive colors and shades somewhat differently than the others.
It is believed that people with varieties of color blindness such as protanopia and deuteranopia perceive the world almost identically. Indeed, in fact, if you mix red with green or green with blue, you get almost the same result. It will be khaki, swamp, greenish and similar shades. By the way, in the presence of one of these pathologies, people do not even distinguish between purple.
An amazing feature is that deuteranopes see the world in a dirty green color, although they cannot recognize it.
Treatment
Protanopia, which is inherited, cannot be treated. In cases of acquired pathology, there is a great chance to get rid of the disease, although to a greater extent it will be just a correction of color perception.
If the problem arose during the course of drug therapy, then the prognosis is quite encouraging, after stopping the use of drugs, vision functions are usually fully restored.
Partially compensate for the defect will help special contact lenses or glasses. Wearing dark glasses slightly reduces the symptoms of the disease.
Social
We rarely encounter unusual diseases such as protanopia. What does the world look like for people with such an anomaly? All surrounding objects and living things have a greenish tint. Accordingly, a person does not receive full information about the environment. Get a number of professions with such a defect will not work, namely:
- the pilot;
- chemist;
- sailor;
- health worker and others.
Today, driver's licenses and protanopia are incompatible in Russia, as well as in Europe. It should also be remembered that if it is revealed that the driver has acquired a certificate of medical examination, then he faces criminal liability for forging a document, and for the use of such a document - a fine of 80 thousand rubles. Although not so long ago in Russia it was possible to obtain a driver’s license with such an anomaly, but special marks were put on the document and it was possible to pass an exam only for category “A” and “B”.
Interesting Facts
There is a myth that dogs are monochromatic, but this is completely untrue, they see the world in the same way as ordinary people.
An interesting fact is that color blindness was first discussed by the public in 1875. Then there was an accident on the railway in Sweden (near the city of Lagerlund), as a result of which there were many victims. After the investigation, it became clear that the driver just did not distinguish the red color.
Surprisingly, it is a fact that the largest number of color blind people live in Slovakia and the Czech Republic. And the least people with color deviations on the islands of Fiji.
Among famous painters, there are many people with distorted color perception, these are Vrubel, Van Gogh and Repin. The latter, when he decided to correct his painting “Ivan the Terrible and his son Ivan”, being already at an advanced age, simply began to spoil it and work was stopped.
Modern developers of computer software for a reason make almost all the interfaces of their products in blue. This color is most favorably perceived by all people.