Violation of color vision, congenital disorders. color vision anomalies

Men! Is it difficult for you to choose clothes so that they harmonize in color, choose ripe fruits among fruits, distinguish color images on a computer monitor, green and red traffic lights? Or does someone help you do it? This suggests that you have a color vision disorder or, as they also call it, a violation of color vision.

This problem is observed most often in every 12th Caucasian man and in every 200th woman. Most color blind people see other colors in addition to black and white, but they perceive some of them differently than a person with normal vision. As a rule, color vision impairment is inherited. The damaged gene disrupts the light sensitivity of retinal cells or the inner lining of the eye. But sometimes color vision can be impaired by a disease, then you need to contact an ophthalmologist.

In the human retina, there are usually three types of light-sensitive cells or cones that are sensitive to light waves of a certain wavelength and correspond to colors: blue, green and red. Each type of cone absorbs its own light wave and sends impulses to the brain and the person perceives the color correctly. But when color vision is impaired, the sensitivity of the cones decreases to one color or several, or the perception of the wavelength changes and affects color perception. Most people with this disorder are color blind: green, yellow, orange, red, and brown. Therefore, they do not notice green mold on black bread or yellow cheese and do not distinguish a blond from a red-haired person. When the sensitivity of cones, which are responsible for the perception of red, is sharply reduced, then a red rose seems black to them. Cases of color blindness to blue are very rare.

As already mentioned, photosensitivity disorder is inherited and, as a rule, is congenital. But many learn about it only when they grow up. The fact is that in children, the impaired perception of colors is often compensated by the ability to distinguish them unconsciously by brightness or contrast. Children associate their perceptions with common color names. In addition, they learn to distinguish objects by shape or texture, and not by color. And as adults, they learn that they suffer from a violation of color vision since childhood.

The school often uses colored aids, especially in elementary grades. And if the child does not know how to correctly distinguish colors, then teachers and parents mistakenly conclude that the child is not capable of learning. And in fact, he may have a violation of color perception. Sometimes the teacher even punishes the child for drawing green people, brown leaves on trees and pink clouds, but the child considers such colors to be completely normal, he just has color vision impaired. In some countries, for this reason, even young children are examined for color blindness.

Although color perception disorder is considered incurable, it does not worsen other visual functions over the years. But, nevertheless, this disease in some causes emotional distress.

Why is color vision impaired mostly in men? The X chromosome is responsible for inherited color perception. Women have two X chromosomes, while men have one X chromosome and the other Y . When a gene is damaged on one X chromosome in a woman, it compensates for a healthy gene on the other X chromosome and she retains normal vision. And men do not have a spare X chromosome, so the defect is not compensated.

How is a color vision test performed?

An eye test for color perception is carried out according to special tables with the image of many multi-colored circles. The 38 Ishihara tables are often used for this purpose. If a person has normal vision, then looking at the tests on the left in daylight, he will see the numbers 42 and 74. If a person has a violation of the perception of red and green (this most often happens), then he does not distinguish the number above, but sees the number 21 below. The tests given here are only an example, as the examination should be carried out by a qualified doctor. If a violation is detected, the doctor will prescribe an additional examination to determine the cause - it is hereditary or acquired.

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Drivers, namely: in addition to the updated form received by the applicant for drivers after passing the commission, the procedure itself and the list of doctors giving the go-ahead for the right to drive a vehicle have somewhat changed. So, today the conclusion of such doctors as an ENT and a neurologist will be mandatory only for truck drivers. A visit to an ophthalmologist remains unchanged, which is mandatory for everyone, regardless of the category received. Checking color perception, checking vision are an essential test for everyone who wants to drive a car. If everything is clear with visual acuity, then let's figure out what a color perception test is for drivers and whether it is possible to prepare for this test.

What is color vision?

Color perception is the ability of the human eye to distinguish between a range of different colors. The cone cells in the retina are responsible for color perception. Normally, a person has three color-perceiving apparatus in the eye, which are excited to varying degrees under the influence of various wavelengths of radiation (red, green and blue). If the eye is not able to distinguish one color from another, that is, if the retina of the eye is not able to "catch" the difference in the wavelength of the radiation, then there is a color vision disorder. Like most diseases known to science, color vision disorder can be either acquired (observed in diseases of the optic nerve and retina) or congenital. The inborn inability to distinguish colors - color blindness - is a serious, insurmountable obstacle to obtaining a driver's license.

Diagnostics of color vision

So, how is a color vision test done for drivers? To determine color blindness among drivers in the arsenal of ophthalmologists, there is a special method that allows you to accurately identify this pathology. This method includes a variety of polychromatic color vision tables for drivers, namely: Ishihara, Fletcher-Gambling, Stilling, etc. However, the most common diagnostic method is Rabkin's tests. Such tables are some kind of drawings collected from dots and circles of various diameters and colors. A person who has deviations in color perception simply will not be able to distinguish and distinguish one color from another, therefore, will not be able to see the latent image.

The book for checking the driver's vision for color perception consists of a set of Rabkin tables that differ in their “purpose”: for example, the first 27 pictures are designed to identify color vision disorders, as well as its form. The remaining images in the book for checking the color perception of drivers are needed to confirm and clarify the diagnosis.

Conditions for the color perception test

To obtain a reliable color perception test result for drivers, a number of conditions must be met:

• The study is not allowed to be carried out under artificial lighting of the room. The normal state of health of the diagnosed person guarantees an accurate result.
• The subject should be "against the light", that is, sit with his back to the window.
• The book for checking the color perception of drivers with tables from the patient's eyes should be at a distance of 1 meter, and the tables themselves should be placed strictly vertically.
• The time allotted for viewing one image is no more than 7 seconds.

Diagnostic results

A color vision test for drivers can reveal a decrease in the perception of one of the colors being examined (green or red), called anomalous trichromasia, divided into three types:

• Complete loss of perception of red or green colors corresponds to type A.
• Significant violation of color perception - type B.
• A slight decrease in color perception by the patient is characterized by type C.

In addition to anomalous trichromacy, Rabkin's polychromatic tables are able to detect rarer types of deviation in a patient: dichromasia (non-perception of one of the three colors), as well as monochromasia (when the subject is unable to distinguish two colors at the same time).

Treatment of color vision disorders

A color vision test for drivers can detect both congenital and acquired color blindness. If we are talking about congenital pathology, then, unfortunately, science does not yet know the methods of treating this dysfunction of the retina. The only way for color-blind people to see the world as it is, in its full glory, is only the development of Western scientists - special contact lenses. In addition, geneticists do not lose hope in the development of a special technology that allows introducing the missing genes responsible for color perception into retinal cells. Perhaps someday the efforts of scientists will bear fruit, and the term "color blindness" will remain in the distant past.

As for the acquired inability to distinguish colors, when assessing the possibility of its cure, the causes of this deviation should be taken into account.

• Color blindness, which appeared as a result of age-related changes in the eye, cannot be cured. However, science knows cases when the replacement of the lens returns normal color perception.
• Violation of color perception caused by any chemical drug can be completely cured - you just need to cancel these drugs.
• In case of violation of color perception caused by any injury, the outcome will depend on the degree of damage to the retina. In some cases, it is possible to completely restore perception to a normal value.

Is it possible to “bypass” the vision test for color perception

Unfortunately, if the patient suffers from a color perception disorder, then it is almost impossible to successfully pass the color perception test. The option to memorize the tables is rather doubtful, since the doctor can give the subject pictures selectively or in a different order. The only way out is to "negotiate" with the doctor. But in this case, you need to understand the seriousness of this act, because in the future the lives and health of not only yours, but also those around you may depend on it. If even changing the traffic light makes you difficult, then you need to think about whether it's worth the risk.

Diagnostics of visual functions in ophthalmology is not limited. Many parameters of the eye are no less important.

So, color vision screening is necessary to identify and correct various types of color blindness.

Color vision impairment is common.

Color blindness is a reduced or absent ability to see the difference between certain colors.

With complete color blindness, a person is not able to distinguish between certain colors, and with impaired color perception, it becomes difficult to distinguish between different colors. Unlike most other eye diseases, color blindness does not affect visual acuity.

The main functions of the human visual apparatus are determined by the structural features of the eyeball. Transparent and translucent structures, which include, the lens and, refract light rays and direct them exactly to the retina. In turn, the retina determines the primary perception of visual information.

Specific receptors of the retina, cones, which contain protein pigments for the perception of red, green, blue and their shades, are responsible for distinguishing colors. Usually, a color perception disorder is due to a violation of this particular functional link.

Various forms of color perception disorder are usually inherited. In men, the disease manifests itself more often. Most people with these disorders are unable to distinguish between certain shades of red and green, but sometimes the pathology is also associated with the perception of blue and yellow.

Such unpleasant features of vision prevent people from engaging in certain types of creativity and mastering professions where color perception can matter.

Symptoms and signs

Often, people with a color perception disorder are not even aware that they have such a disease. Suspicions may appear after various situations when the observed color of certain objects in color blind people does not coincide with the perception of healthy people.

Also, often even the most minor violations of color perception attract attention when a person learns to draw. People suffering from a color perception disorder may show the following symptoms:

• Violation of the perception of shades of red and green.
• Impaired perception of shades of blue and yellow.
• Violation of the perception of all colors at once.

The problem with the perception of red and green is the most common. In this case, the defect in visual function can be weak, moderate and severe. In severe impairment of function, a person does not see any difference between the colors.

Types of color blindness

Based on the possible clinical manifestations, color blindness can be complete or partial. Complete color blindness is much less common.

With a partial violation, a person does not perceive shades of two colors and in most cases observes their mixture with a predominance of one shade.

The main types of violation of color perception:

• Protanopia is a rare disease that occurs in 1% of men. Usually due to the absence of cones with red pigment, because of which the predominantly red-green spectrum of perception suffers. For protanope, the brightness of red, orange and yellow colors is significantly reduced relative to normal values. However, people with this disorder can learn to distinguish between reds and yellows based on subjective brightness.
• Deuteranopia is a rare disease, also occurring in 1% of men. It is due to the absence of cones with a green pigment, which is why the patient does not distinguish between shades of green, red and yellow. Deuteranopes experience the same color perception problems as protanopes, but without subjective dimming.
• Tritanopia is a rare disease that occurs in 1% of men and women. Pathology is due to the absence of cones responsible for the perception of short-wavelength colors. For such patients, shades of blue and green look dull and inexpressive, and purple is perceived as a shade of red.
• Complete color blindness is a violation of the perception of all colors. It can be congenital or acquired. In this case, patients usually can only distinguish the brightness of colors.
• Acquired color blindness is a color vision disorder caused by damage to the retina. The cause may be a neurological pathology, or any other disease that affects the visual apparatus.

The congenital form of color vision disorder is much more common.

Possible reasons

Different types of color perception disorders are due to the structure and ratio of retinal cones.

Accordingly, the causes of diseases can be associated both with the inherited state of the receptor apparatus of the eye, and with various pathologies affecting the retina.

The hereditary form is much more common among men, although the pathological genes are located on the X chromosome. Other reasons:

1. Parkinson's disease is a severe neurological disorder characterized by a progressive course.
2. The neurological nature of the disease determines the possible damage to the nerve cells responsible for color processing.
3. Cataract is a change in the structure of the lens that affects the function of vision. The clouding of the lens that occurs with this disease also affects color perception. For people with this disease, the colors look less bright and distinguishable.
4. Side effects of drugs. An antiepileptic drug known as tiagabine has been shown to impair color perception in 40% of cases. However, this side effect goes away with time.
5. Hereditary optic neuropathy is a common hereditary disease among men that affects the condition of the optic nerve. There is a violation of the perception of the red-green spectrum of colors.
6. Kallmann's syndrome is a hereditary disease associated with damage to the pituitary gland. Pathology mainly affects the development of sexual functions, but can also be the cause of impaired color perception.
7. Other diseases: Alzheimer's disease, glaucoma, chronic alcoholism, leukemia, sickle cell anemia, diabetes mellitus and macular degeneration.
8. Aging. The retina can also wear out with age.
9. Exposure to chemicals. Some chemicals, including carbon disulfide and fertilizers, can affect the retina and cause color impairment.

If color blindness is associated with a primary curable disease, then appropriate therapy solves the problem with the perception of colors.

Diagnostics

Identification of diseases that affect color perception is not difficult. Pathology can be diagnosed during a routine consultation in the ophthalmologist's office.

The standard color perception test uses polychromatic charts with squares containing numbers, shapes, and pictures. The main image differs from the background only in color, while the brightness remains uniform throughout the image. Patients with impaired color perception cannot distinguish a number or figure.

Special tables, as a rule, contain several squares with which you can identify various types of color blindness. This diagnosis only takes a few minutes. In this case, if the doctor suspects a non-hereditary etiology of the disease, additional research methods may be prescribed.

Additional diagnostics:

1. - a method of studying the fundus using an optical device. Allows you to diagnose diseases of the retina and optic nerve.
2. Retinoscopy is a detailed method for examining the retina and its vessels.

Since a color vision problem can have a significant impact on a person's quality of life, it is recommended that a diagnosis be made as early as possible. Children's vision should be tested before age 6 to avoid sudden learning difficulties.

How to fix color vision?

Doctors have not yet learned how to treat a hereditary color perception disorder. If the problem is associated with a primary disease of the visual apparatus, then appropriate treatment will restore color perception.

Correction methods:

• Wearing colored ones. With such lenses, a person can begin to see differences between colors even in the absence of specific retinal cones.
• Wearing special glasses. The lenses may have an anti-reflective coating.

Not all people with such a problem require correction, since in many cases the violation of color perception is almost imperceptible. In addition, patients with a color perception pathology often adapt to discriminate shades using subjective perception of brightness.

Thus, color blindness and other types of color vision disorders are predominantly hereditary conditions. A quick vision test for color perception will help make the correct diagnosis.

How is the study of color vision will show the video:

Incorrect color perception is a pathological change in visual function and can significantly affect the quality of life. These disorders are observed both congenital and acquired. Consider the features of color vision disorders, their varieties, causes, methods of diagnosis and correction, as well as how this may affect the receipt or replacement of a driver's license.

What is color vision

The human brain is capable of distinguishing a wide variety of shades. The retina, more precisely, cone cells, is responsible for this ability. In a healthy person, color is perceived by three devices that are sensitive to waves of different wavelengths and radiation. If the eye does not distinguish one color from another, this indicates a violation of color perception.

Pathology can be acquired (with diseases affecting the area of ​​the optic nerve or retina) or congenital. In this case, the violations are called color blindness. With such a diagnosis, a driver's license is not issued.

Types of color vision disorders

A person who perceives all three primary colors (red, green and blue), that is, uses three apparatus to perceive them, is called a trichromat. Pathological changes related to color perception are divided into two main groups.

Congenital disorders, as a rule, apply to two eyes at once. They can be identified only with the help of a special study. Color blindness does not entail a loss or reduction in the quality of other visual functions. Most often, congenital anomalies are inherited. These faces perceive only two colors, but in a slightly different proportion than trichromats.

Types of congenital pathology:

• Deuteranomaly - it is the green tint that is poorly perceived.
• Protanomaly - the red color is almost invisible.
• Tritanomaly - invisible blue tint.
• Dichromasia - visual receptors do not perceive one of the three shades at all.
• Monochromasia - “color blindness”, that is, a person sees everything only in black and white.

Colorblindness pathology is named after the scientist John Dalton, who himself suffered from impaired perception since childhood.

Acquired color vision disorders are most often the result of diseases of the retina, central nervous system or optic nerve. Pathology can spread to one or both eyes at once.

Types of acquired disorders:

• Xanthopsia - everything is perceived in yellow.
• Erotropsia - in red.
• Cyanopsia - in blue.

Unlike congenital pathology, which cannot be corrected, acquired anomalies can be eliminated if the cause of the disease is eliminated.

Color perception is checked with an instrument called an anomaloscope. Railway drivers and workers transport must pass this study.

Causes and symptoms

As noted above, the congenital type of color perception disorder is hereditary. The disease is transmitted from the mother via the X chromosome. Most often, representatives of the stronger sex suffer from color blindness, since they lack the maternal chromosome with such a gene. In order for a girl to be born with congenital color blindness, it is also necessary that her maternal grandmother also suffer from impaired visual function regarding the perception of shades.

Acquired pathology can occur for the following reasons:

• Stroke.
• Head injury.
• Cataract or other pathology of visual function in the absence of therapy.
• Diabetes.
• body intoxication.
• Diseases of the nervous system.

The symptomatology of color blindness does not depend on the type of disorder (congenital or acquired). It lies in the fact that a person cannot distinguish certain shades, while visual acuity may not be impaired.

Diagnostics

To determine if a person has a violation of color perception, ophthalmologists conduct a series of studies. The most commonly used polychromatic tables are Fletcher-Gambling, Ishihara, Stilling and others. In the Russian Federation, Rabkin's tests are widely known, which are passed by all drivers of vehicles.

All methods are the same according to the principle of action, they are presented in the form of drawings from dots or circles of different diameters and shades. If you look closely at the picture, then a certain picture made in other colors will be visible through the main background. If a person has a pathology regarding the perception of color, then he will not consider what is shown in the figure.

Also in ophthalmology, the FALANT test and a device called an anomaloscope are used. It is used to test people when they are admitted to certain specialties where it is important to clearly distinguish colors. With the help of the device, it is possible to diagnose a type of violation, as well as how brightness, age, noise, training, medications affect a person’s color perception, that is, visual receptors are studied in a complex.

The FALANT test is passed by all persons liable for military service in America. To do this, you need to determine the color that shows the beacon at a certain distance. Those who suffer from color blindness do not pass such a test. But 30% of people who have slightly impaired perception can successfully pass the test.

Rabkin's tables

Violations of color perception are allowed when obtaining a driver's license, but only to a small extent. The most common in Russia are Rabkin's tests, which consist of 48 tables. They are divided into two groups: basic (27 tables) and control, which are used in case of questions and the need to detail the visual function.

Rules for testing according to Rabkin's tests:

• The monitor screen on which each picture is displayed should not be too bright or dim.
• All tables should be at eye level. Positioning higher or lower may affect the accuracy of the test.
• There is a time limit - 5 seconds per picture.

As a rule, to check whether a person has color blindness, it is enough to pass the test on the first 27 pictures. The specialist indicates the diagnosis, as well as the degree of anomaly (weak, moderate or strong).

Methods for correcting violations

Congenital pathology is not yet correctable, although Western scientists have invented special contact lenses with which color-blind people can see the world in different colors. Geneticists are also developing methods to introduce into the cells of the retina of the eye genes that are responsible for the perception of shades.

Congenital inability to distinguish colors does not progress. Colorblind people have been learning colors since childhood, and this one does not affect their quality of life in any way.

To cure acquired color blindness, it is worth identifying the root cause of the pathology and eliminating it. If the anomaly appears as a result of age-related changes, it is practically incurable, although people have a chance to correct the situation by replacing the lens. If color perception is caused by the influence of some chemical preparation, it must be canceled. If the pathology was the result of an injury, it all depends on the degree of destruction of the retina.

Acquired disorders of color perception initially appear in one eye, and then spread to the other. At the same time, visual acuity also decreases. It is important to identify pathology at an early stage.

There are no effective (surgical or therapeutic) methods of correction that would cure violations in the perception of colors. But medicine does not stand still.

For the first time, they started talking about color blindness and driving a car at the end of the 19th century. In 1975, there was a major railway accident in Sweden. The driver turned out to be the culprit, who could not recognize the red color of the traffic light. After this incident, drivers and railway workers began to be additionally checked not only for the quality of vision.

Many car owners are interested in the question of whether it is necessary to replace a driver's license in case of a violation of color perception?

In Russia, until 2012, people with a mild degree of color blindness were allowed to drive a car (categories B and C), using it for personal purposes. In 2017, the rules have changed. According to the legislation of the Russian Federation, it is no longer possible for color-blind people to drive a car. Such a driver poses a serious danger to other road users and pedestrians.

If it's time to change your driving license, a color test is inevitable. In 2018, the chances of getting a driver's license from color blind people are minimal. In developed countries, it is allowed to drive a vehicle for those who constantly wear colored contact lenses or glasses. With the help of them, the color-blind world becomes multi-colored, that is, the way an ordinary person sees it.

Is it possible not to pass the test according to Rabkin's tables

Great yogis or mahatmas said about the violation of color perception that these are special people. Unfortunately, such car owners cannot successfully pass the test for the ability to distinguish colors. Theoretically, you can memorize all the pictures. But the doctor may show them out of order, which significantly reduces the chances of success.

Some believe that you can always negotiate with an ophthalmologist. But in this case, it is worth assessing whether such a risk is really justified. After all, not only other road users, but also the driver himself can be at risk. If you can't tell how the colors change at the traffic lights, you shouldn't drive.

Conclusion

Persons with color perception disorders lead a completely normal life, with the exception of some discomfort. Color-blind people are somewhat limited in their choice of profession; they cannot become military men. Also, since 2017, car owners who suffer from color blindness have practically no chance of obtaining a driver's license.

Functional defects of the cone system are due to hereditary factors and acquired pathological processes at various levels of the visual system.

Congenital disorders of color perception are expressed in the inability to distinguish light radiation, distinguishable by a person with normal color vision. These disorders are associated with genetic defects and are inherited. Although color vision disorders are observed much less frequently in women, they are carriers of the pathological gene and its transmitters. Congenital disorders of color vision are most often associated with dysfunction of one of the photoreceptors. There are three types of congenital color vision disorders: a defect in the perception of red (protan defect), green (deuter defect) and blue (tritan defect). According to the degree of violation, each of the species is divided into abnormal trichromasia, protanopia, deuteranopia and monochromasia.

Congenital disorders of color vision occur in 7-8% of the population. The frequency of color anomalies in men is 10-15 times higher than in women.

Acquired color vision disorders are understood as all changes in color perception caused by pathological processes in the retina, optic nerve, and overlying parts of the visual analyzer. They can occur with somatic diseases of the body and its intoxication. Acquired also include color vision disorders that occur as a result of genetically determined and acquired diseases of the retina. Acquired color vision disorders are always secondary, so they are determined randomly. Depending on the sensitivity of the research method, these disorders can be diagnosed already with an initial decrease in visual acuity, as well as with early changes in the fundus. If at the beginning of the disease a decrease in chromatic sensitivity can concern either red, or green, or blue, then with the development of the pathological process, sensitivity to all three primary colors decreases, more often to green, then red and blue.

E. B. Rabkin subdivided, for example, acquired color vision disorders into forms similar to congenital color disorders, forms not similar to congenital color disorders, and mixed forms.

The first fairly coherent clinical classification of color vision disorders was the Kries-Nagel classification. J.V. Kries (1907,1911) proposed to designate incomplete color blindness, i.e. blindness to individual colors, the terms prot-, deuter- and tritanopia. The term anomaly, already then used among specialists, was applied by J.V. Kries to the weakening of the color sense. So, in the classification of Chris-Nagel, the graphs of prota-, deuter- and tritanomalies appeared. In prota- and deuteranomalies, E. B. Rabkin (1971) introduced subgroups (ABC): A - a sharp decrease, B - medium, C - mild. Based on colorimetric measurements in the pursuit of an etiopathogenetic substantiation of the mechanisms of both congenital and acquired color perception disorders, J. V. Kries (1911) identified three systems:

1. Absorption (explains a color anomaly by a violation of the passage of "color" through an absorption system, such as a pigment);

2. Alteration (deuteranomaly and protanomaly, congenital forms of anomalous trichromasia, in which there is a change in the perception of light in some part of the visual system, which is interpreted as a violation in the alteration system);

3. Reduction (deuterium and protanopia, both forms of congenital dichromacy are designated as reduction of the normal trichromatic system).

In this case, the absorption system is realized through a pathological prereceptor filter with normal retinal mechanisms. In the spectral zone, the action of the filter "reduces color differentiation" and light sensitivity.

Absorbing media are characterized by a change in the intensity, rather than color, of the homogeneous spectrum of light passing through pathological media; this absorption system is characteristic of acquired color disorders, with cataracts, vitreous opacities, after fluorescein injection.

In subsequent years, G.Verriest (1958-1983) attributed to the alteration system such forms of acquired color anomaly, in which the cone pigment differs from that of normal trichromats. G.Verriest used the reduction system to explain the occurrence of such acquired forms of color perception disorders, in which normal color equations were encountered, the anomaloscope indicators corresponded to deuteranopia, and everything red-green was taken the same.

One of the early classifications [Kollner H., 1912] was based on the results of colorimetric studies of color vision disorders, which made it possible to distinguish two main groups: with changes in the blue-yellow and red-green parts of the spectrum (with the evolution of the disease), as well as progressive red - green blindness with possible inclusion of blue-yellow disturbances. Kellner's rule was: "blue-yellow disturbances are predominantly characteristic of diseases of the retina, red-green disturbances - for diseases of the optic nerve." True, he made exceptions to this rule (with luetic neuritis, the perception of blue-yellow colors was also disturbed, and with macular degeneration, the perception of red-green colors often suffered). Subsequent clinical observations somewhat changed this view.

Clarifying the validity of the "Kellner's rule", W. Jaeger and P. Grutzner (1961) showed that red-green disturbances occur in diseases of the optic nerve that occur without violation of the relative spectral sensitivity curve, and in macular degeneration, there is a decrease in light sensitivity in the area of ​​the red receiver, i.e., the spectrum is reduced from the side of its long-wavelength part.