How a colorblind person sees and an ordinary person sees. Color blindness - what is it, causes and symptoms of color blindness

Some people suffer from visual impairment. Mostly men see colors in altered shades.

This is called color blindness, and similar violation, does not cause discomfort. You can live with this for a long time and not notice changes in the color scheme.

Causes of color blindness

The appearance of color blindness occurs due to a violation of the development of cones. These visual cells help perceive colors. The cones transmit the information they receive to the optic nerve. In deviation they may to sense both one and several visual cells.

Color blindness mainly occurs only in men, but there are rare exceptions. Photochromic substances are formed from a gene where there is an X chromosome.

A woman has two of them, so it is easier for them to replenish the missing substances. A man has one X chromosome and the likelihood of this deviation occurring is high.

Colorblindness can occur due to damage or injury. This may be physical or chemical in nature. It can affect not only the eye, but also the optic nerve, as well as the brain.

There are a number of reasons for color blindness in humans:

after taking medications;
complicated flu;
meningitis;
encephalitis.

Normal color vision

In the retina of the eye healthy person rods and cones are located. They react to light and some are responsible for night vision, while others are responsible for day vision. There are several types of cones. Each contains a specific pigment.

They have their own sensitivity and are divided into:

short;
average;
long.

They differ in color:

blue;
green;
yellow.

When colors work together, they reveal all the shades that a person sees.

In science, receptors are usually classified as:

blue;
green;
red.

This judgment cannot be attributed to precise information, since each cone has perception in a larger range of color shades.

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Colorblind people have trouble seeing red or yellow color. This is observed in most people with this deviation. It all depends on the types of diseases associated with color blindness.

There are two types of deviation:

Full color blindness;
Partial color blindness.

The first type is rarely found. Partial, on the contrary, is common.

What colors do colorblind people see?

A person with complete color blindness perceives the world in almost black and white. Origin This is due to the absence of all three cones.

Colorblind people recognize the following colors:

grey;
black;
green;
brown;
red;
orange.

Depending on the disease, they see only certain combinations.

What colors can't be distinguished?

Colorblind people may not be able to distinguish between red, green or blue. Depending on this, they confuse them with other shades. If a person has tritanopia, then they perceive the color violet. Blindness to all shades of green or red is rarely found.

What colors are confused?

Some colorblind people confuse red with brown, brown and other shades. They cannot distinguish green from red and orange.

Classification of color blindness

The classification of color blindness depends on the shades.

Due to a violation of their perception, the following diseases are distinguished:

Achromasia– a person is not able to distinguish all colors. There is insufficient or no pigment in the cones. Because of this, shades of gray are perceived;
Monochromacy– a person perceives only one color. In some cases, photophobia occurs;
Dichromasia– the organ of vision perceives only 2 colors;
Trichromasia– the human eye sees all colors, but distinguishes them differently. It could be normal deviation or abnormal.

The manifestation of anomalous trichromasia occurs somewhere between dichromasia and trichromasia. A person does not perceive possible shades of the main color spectrum. There is a weakening of the differences between red, green and blue colors.

Types of partial color blindness

If a person does not perceive two colors, then they usually include:

red and green;
blue and yellow.

Along with the indistinguishability of red and green colors, the following diseases are determined:

protanopia;
deuteranopia;
protanomaly;
deutranomaly

If a person has a problem with blue and yellow, then they distinguish:

tritanopia;
tritanomaly.

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Dichromasia

Dichromasia means a disorder of one of the three cones. A certain kind no pigment. A person perceives color shades only in two planes.

Forms of dichromasy

The following forms of dichromasy are distinguished:

Deuteranopia;
Tritanopia.

In a person with protanopia, the wavelength of light is between 400-650 nanometers. IN in good condition this size is 700 nm. This deviation occurs due to a malfunction of the receptor responsible for the color red.

The cones of the eye redirect shades of this color range to black.

The purple color does not differ from blue for the patient. Orange remains almost unchanged, but is recognized as a dark yellow shade. Color wavelengths above 650 nanometers are considered large for the eye.

Therefore, receptors are unable to recognize many shades of orange and green. Protanopia disease occurs in men. The deviation is considered congenital, and it occurs in 1% of the stronger sex.

When a person has deuteranopia, the second cone receptor is missing. There are difficulties in perceiving the color green and all shades of red.

One of the most rare forms dichromasia is considered tritanopia. There is a lack of pigments that recognize blue color and its shades. The patient sees pink instead of yellow, and purple is recognized as burgundy. Experts associate this disease with a disorder in the seventh chromosome.

Anomalous trichromasia

Abnormal trichromasia is common in humans. This does not cause discomfort, and patients are able to recognize colors. There is a slight deviation in the perception of shades.

There are several forms of this type of color blindness:

Protanomaly;
Deuteranomaly;
Tritanomaly.

Protanomaly causes impairment in the recognition of the color red. The patient will see brown or yellow.

The severe form is considered deutranomila. When the perception of red, orange, yellow and green is disrupted and confused.

Many colorblind people have tritanomaly. During this deviation, blue pigment is not perceived.

Represents him as green. Abnormal trichromasia does not affect human life. However, some professions do not provide work opportunities for colorblind people.

Diagnosis and treatment

To carry out diagnosis, special testing is carried out. This is done using images. Colored spots are drawn on them, which turn into one figure. On paper this way Arabic numerals are displayed.

Specialists conduct a complete test to identify a deviation in a person. It especially helps to identify a problem with a certain color.

Other images have been invented for diagnosis in children. They are painted on geometric figures.

Experts cannot offer any specific treatment. They recommend wearing special lenses. If you don't like the lenses, they suggest purchasing them. This method has not given positive results to many people.

In addition, there is a way to slightly adjust color perception. Helps with this Genetic Engineering. During of this intervention the corresponding pigment is introduced into the desired cone. There are cases that color blindness occurs due to diseases. Then diagnostics are carried out in the form of an ultrasound examination.

Treatment for color blindness currently exists, but it is not effective. Many people have to learn to live with this disease. They adapt by observing others.

Prevention

There are no special measures to prevent color blindness. Basically there is a consultation with specialist. This is resorted to when representatives from closely related families marry and plan a pregnancy.

To people suffering diabetes mellitus or cataracts, you should undergo a routine examination. This must be done at least twice a year.

If color blindness is detected in a child, then during classes you should use materials that do not have “difficult” colors for perception.

Observing them helps to identify deviations in color perception. Parents should pay attention to the colors their child draws.

If deviations occur and gray grass appears in the image, you should immediately contact an ophthalmologist. He will conduct an examination and diagnosis. Parents will have to raise their child in new conditions.

The prognosis for incorrect color perception for human life is positive. This deviation worsens the patient’s quality of life. Colorblind people are limited in outside world with the choice of profession of interest. These mainly include areas where correct color perception is considered an important part.

Color blindness is color blindness. People suffering from this disease cannot distinguish colors and get confused in shades - many colors of life are inaccessible to them. Color blindness can be congenital or acquired.

The pathology was first described by John Dalton in 1794 - he discovered that he lacked the ability to distinguish colors. The anomaly occurs due to damage optic nerve or underdevelopment of the retina.

Hereditary color blindness is more common - in this case it progresses with age. The pathology extends to both eyes. The disease is transmitted from mother to son due to X chromosome abnormalities

Colorblindness has a gender preference - it occurs in 8% of men and only 0.4% of women. Much more often they cannot distinguish between yellow and blue, but sometimes it is impossible to determine all colors. The last form of the disease occurs against the background of other quite serious eye pathologies, for example, keratitis (inflammation of the cornea).

The perception of colors is a function of the retina - more correctly, its constituent photoreceptors - cones. They contain pigments responsible for the perception of different shades. If any pigments are missing or insufficient, color blindness occurs.

Types of color blindness

There is a theory that the ability to see the world in colors in humans arose gradually - ancient people did not distinguish all shades. The cooperative work of cones, which contain green, blue and red pigments, has evolved over time.

People - even in the absence of color blindness - have different perceptions of shades, this individual feature everyone. In addition, there are racial and national differences in perception. It is believed that the Japanese distinguish the most shades, but the peoples of the Far North often confuse even the primary colors.

In the former CIS, Rabkin tests are used to identify color blindness - special pictures in which numbers for adults and figures for children are depicted in different colors of the same saturation. If the patient does not distinguish colors, then he does not see the images.

Modern medicine distinguishes 4 types of color blindness - anomalous trichromasia, dichromasia, monochromasia and achromasia.

Anomalous trichromasia

This form of color blindness is the most common. It does not cause serious problems for those suffering from the disease - they can see the world in colors, their picture is not much different from the real one.

The features of vision can be classified as follows:

protanomaly - the perception of red color is impaired, because of this it is confused with brown or yellow;
deuteranomaly - this feature is more difficult to live with - red, orange, yellow and green are confused.
tritanomaly - most common - blue color feels like green.

Trichromasia limits the choice of professions, but has little effect on the perception of the surrounding world.

Dichromasia

Colorblind people with this type of anomaly cannot distinguish between yellow, green, red and orange.

Three types of pathology can be distinguished.

That is, with dichromasia, one spectrum is always excluded from life.

Monochromacy

It's more serious pathology, in which the signal that transmits information about the color shades of the spectrum passes through one channel. In this case, the world is monochromatic and only brightness is perceived.

There are several types of anomalies.

Rod monochromasy - there are no cones responsible for the perception of color shades. That is, the eyes perceive information, but the brain does not receive it.
Cone monochromasia - the brain receives information only when there is sufficient illumination. There is not enough light - color images are erased from the retina.
Blue cone monochromasy. Symptoms of the condition are myopia, intolerance to bright light, periodic eye trembling, loss of visual acuity. How do colorblind people with this pathology see? They cannot perceive color.

Achromasia

The colors are not different at all. If achromasia is congenital, this is explained by maculitis - lesions of the retina in the central part of the eye. Acquired disease is caused by injury eyeball or its infection.

In this case, it is not only impossible to distinguish colors, but vision is so impaired that the person orients himself in space by squinting.

Diagnosis of color blindness

To find out exactly which colors a colorblind person cannot distinguish, special testing is used.

The already mentioned Rabkin tables, pseudo-isochromatic test, color distribution test of objects.

Patients are asked to evaluate the totality of colored dots and shades; they need to sort the plates by color. Based on the cumulative test results, the degree of color blindness and, accordingly, visual impairment are determined.

Some patients try to prepare for tests by memorizing numbers and pictures. However, it is impossible to fully cope with the totality of tests for color blindness.

How colorblind people see the world - life's limitations

Because of their peculiarity, colorblind people feel defective - they cannot perceive the beauty of the world around them - they understand that others see differently "Pictures". Many professions are inaccessible to them medical indications– where it is necessary to distinguish colors without fail.

The following professions are not permitted:

career military personnel;
sailors;
pilots;
chemists.

If a colorblind person tries to draw, then his works will be rejected by the general public.

We should not forget that complexes are formed in childhood. Peers who confuse colors are laughed at in the children's group, they become outcasts. To prevent rejection in childhood from spoiling the rest of life and causing severe moral trauma, parents, as soon as they notice that their children are confusing colors, should show the child to an ophthalmologist.

About the diagnosis "color blindness" educators should be aware kindergarten and - further - school teachers. If the child’s characteristics are taken into account, there will be no problems with mastering the school curriculum.

It’s interesting that in the territory of the former CIS you can get driver license colorblind

very hard. But in Europe they are treated much more loyally - documents are almost always issued, with the exception of people suffering from monochromasia and achromasia and having serious problems with the quality of visual acuity.

Modern medicine does not yet have the ability to cure color blindness. This is largely due to the nature of the disease – hereditary gene damage.

Most colorblind people are far from art, but every rule has its exceptions. Such brilliant artists as Vrubel, Savrasov and Vincent Van Gogh created without knowing about their peculiarity. Their works captivate the general public to this day. The phenomenon of Savrasov, the Itinerant artist, is quite possible to explain. Rooks conquered it precisely because colorblind people can distinguish 4-5 times more shades gray than people with normal vision.

There are other people for whom color blindness did not prevent them from achieving success: singer George Michael and French artist Charles Merion.

You shouldn’t be upset about your illness – the main thing is not to give up and go towards your goal.

Until he was 26, he had no idea that he was unable to distinguish the color red. He had two brothers, and they were also color blind. Interestingly, the sisters did not have such a problem.

Dalton wrote a book in which he talked about all the nuances of his illness. Thanks to this description, any violation of color perception began to be considered color blindness.

The anomaly interested scientists who conducted a number of studies. It turned out that color blindness is a disease inherited from mother to son with the X chromosome. Men have XY chromosomes. If a defect is present in the X chromosome, then there is nothing to compensate for it, which is why the anomaly is twenty times more common in men.

Women have a pair of X chromosomes, so the missing elements can be replenished. Statistics show that approximately 8% of men are colorblind, while among women they are only 0.4%. Cunning nature has endowed women with the ability to transmit color blindness without suffering from it themselves.

In addition to heredity, there is another reason for the development of color blindness - chemical or physical damage to the eye.

The fate of becoming colorblind may also await those who have suffered damage to parts of the brain or optic nerve. Severe flu, heart attack, stroke - all this can affect the perception of colors.

The world through the eyes of a colorblind person

It is a common belief that colorblind people see the world in black and white, but this is not true. This phenomenon is very rare; usually colorblind people do not perceive any one of the primary colors. Most often it is red.

The cones are located in the center of the retina. They contain pigments that are sensitive to the wavelengths of red, blue and green. Thanks to their addition, people are able to see the world in different colors. Only ophthalmologists can correctly explain how colorblind people see the world.

Scientists distinguish two types of color blindness – dichromasia and anomalous trichromasia. The subtype of the disease determines which colors are distorted in a person.

Dichromasia- violation medium degree, manifests itself due to the malfunction of one of the three receptors. This type of color blindness is divided into three forms:

Protanopia is a complete dysfunction of red color perception. More often than not, a person sees everything red as black. Blue and purple appear the same to each other, but orange appears dark yellow. The anomaly occurs in 1% of men.
Those who do not have photoreceptors of the second type do not distinguish between red and green. This form is called deuteranopia.
A rare form, but still occurring, is tritanopia. Characterized by a complete absence of blue pigment. Man sees green color instead of blue, pinkish instead of yellow and orange, and purple appears dark red.

The second type of color blindness is anomalous trichromasia. In practice, there are three forms of dichromasia:

The problem of seeing the color green is called deuteranomaly. The anomaly replaces green with orange or red.
The inability to perceive the color red is protanomaly. Instead of red, a person sees brown, black, green or dark gray.
Blue and purple colors those with tritanomaly do not see. In this case, a person is not able to distinguish between blue-green and yellow-red colors.

By the way, immunity of blue color is very rare. That is why the design of many computer programs made in this color.

There are more serious disorders– monochromasia and achromasia.

Monochromacy is a pathology in which they cannot distinguish colors at all, but perceive brightness well. A person is not able to see the world in those bright colors, which he can please people with normal vision.

Achromasia- an even more complex pathology in which a person not only does not distinguish colors, but also has reduced visual acuity and photophobia. Because of this, he has to constantly squint. Simply put, this condition is called color blindness.

Colorblind people have good eyesight, they just see a little distorted. They cannot even be called sick, since their peculiarity does not cause discomfort or impair the clarity of vision. Sometimes color blindness goes unnoticed not only by others, but also by the owner of an unusual vision of the world.

It is difficult for an ordinary person to imagine how colorblind people see colors - sometimes this is the subject of controversy or jokes. It is important to remember that such a special person will have to come to terms with his worldview for the rest of his life.

Diagnosis of the disease

To identify problems with color perception in humans, doctors use a certain test - Rabkin’s polychromatic tables. Among the circles different color numbers and figures are drawn. A person with normal vision will immediately see what is shown in the picture.

Colorblind people make great efforts to see the drawing, and some people do not succeed at all. The same test has been developed for small children, only it contains various geometric shapes.

Now anyone can find these tests on the World Wide Web and independently determine whether they have color blindness, determine its type and shape.

There are spectral devices that are also used in diagnosing color blindness. Most often they are used when applying for jobs in professions whose employment involves driving.

In practice, there have been cases where color blindness led to accidents, which is why employers so carefully check workers who are responsible for people’s lives.

The first case that attracted everyone's attention occurred in Sweden in 1875. Then there was a train crash that took away many human lives. It turned out that the driver simply did not distinguish the color red and was not aware of this feature of his vision.

Not so long ago in Russia, color blindness was a reason for restrictions in issuing rights, and now the laws have become even stricter. In Europe there are no restrictions on issuing licenses to colorblind people.

After all diagnostic procedures the doctor informs the patient about what form of color blindness he has and what limitations may be encountered in his life.

Regarding treatment of this disease– they don’t exist. There are correction methods - lenses and glasses, but they are rarely used. Scientists are conducting experiments using monkeys to develop a treatment and there are already some positive results.

Features of everyday life with color blindness

The man who sees environment The eyes of a colorblind person may certainly feel uncomfortable because of his anomaly. Those professions that require the ability to clearly distinguish colors become inaccessible to him. He will not be able to pass the medical examination and the job will be denied.

For example, a colorblind person will not be able to be a designer, since it is also important to recognize colors correctly.

As for a driver's license, a colorblind person can obtain one after certain training.

The restrictions that will be inevitable for him are the rights of categories A and B only, as well as a mark that will not allow him to work for hire. A car or motorcycle can only be used for personal purposes.

The question inevitably arises: how do colorblind people see traffic lights? This is not a problem, since colorblind people do not look at the color, but at the switching of the lighted windows.

Therefore, they can accurately determine when to stop and when to start moving again.

Now there are special glasses for driving, but ophthalmologists believe that long-term wearing causes additional strain on the eyes. There are also lenses that help distinguish colors. But at the same time, they make it difficult to perceive other colors.

If a person has a serious form of color blindness, he will need help in choosing interior design, clothing, and products. A colorblind person may forget that he sees color incorrectly and end up in an awkward situation.

Among the world famous people There were also colorblind people, but their flaw did not prevent them from achieving fame.

French artist Charles Merion, Van Gogh, Vrubel, Savrasov and Repin - all of them learned firsthand what colors colorblind people see.

True, the last two Russian artists are color blind due to old age and illness. Repin tried in his old age to correct his painting with Ivan the Terrible, but he distorted the color scheme so much that the work was stopped.

One day, a German ophthalmologist tested the vision of 342 artists. Of these, 31 turned out to be color blind. Most of One of them switched to graphics from her favorite hobby of painting.

Nowadays, for a person of art, there is a profitable type of work that is popular - black and white photography.

Don't get hung up on how colorblind people see the world. You can always find them mutual language and not concentrate on its small features.

This will give the colorblind person confidence and make him understand that he is no different from ordinary people. His little “zest” does not cause him physical discomfort, he does not need special care, which means he can fully enjoy life.

Useful video about color blindness

Color blindness is a disease in which a person can't recognize some colors spectrum

There are also forms of pathology in which the patient completely absent color vision.

Types of color blindness: what colors does the eye not distinguish?

This disease is not so rare. Since color blindness is predominantly hereditary disease, most often it manifests itself in people living in closed communities.

Here, recessive (hidden) traits become homozygous, that is, pure form. Dominant (suppressive) signs of normal color vision are absent in such people, and therefore pathological color perception appears.

Where people are highly mobile, their genomes are characterized by heterozygosity (a variety of dominant and recessive traits), which reduces the likelihood manifestations of hereditary pathologies, including color blindness.

How people see in different categories of illness

The disease is divided into the following categories.

Anomalous trichromasia. This is a pathology of color vision in which a person does not fully distinguish between the three primary colors. This happens due to the absence of some cones or their incomplete functioning. Depending on which cones in the eye do not work, they are divided protanopia(incomplete perception red colors), deuteranopia(problems with perception green shades), tritanopia(the person does not see blue). Thus, with anomalous trichromasia, the patient is in a colored world, but the spectral range of the latter is somewhat different from the norm.

Photo 1. An example of how the picture changes with trichromasia different types compared to normal color perception.

Dichromacy. A person with such a pathology sees the world in shades two primary colors. While a healthy individual can distinguish all shades of green, yellow, red, blue colors, a colorblind person with dichromacy sees only shades of red or green, not counting all the transitions of black and white.
Monochromacy. This is a complete inability to see colors. Occurs due to a severe defect in the cones or their absence. Complete color blindness is rare, since from the standpoint of evolution it does not contribute to the survival of the individual. IN wildlife an individual with monochromacy loses to those who see the world in all its diversity of colors.

The most severe defects vision - dichromacy and monochromacy. People with such forms of the disease have limitations in the professional sphere. They have to solve many problems in everyday life: from color recognition in a traffic light to orientation in space using various identification marks.

Problems of colorblindness and overcoming them

It would be logical to describe the problems of people with color perception defects using the example of John Dalton.

This scientist who lived at the turn of the 18th and 19th centuries, knew almost nothing about the peculiarities of his vision up to 30 years old. One day he decided to study botany.

In this science, it is extremely important to distinguish the color shades of all parts of the plant. Here it turned out that Dalton could not adequately navigate the shades of the red spectrum.

It was difficult for Dalton to study botany, but nothing stopped the scientist describe in detail the manifestation of the visual defect, which was common to all his brothers and sisters. Since then, the surname Dalton has become the name for a disease that is associated with certain features of the human genome.

Attention! To ensure effectiveness, assessments have been developed different ways detection of color vision disorders. Duplication of techniques is carried out so that a person trying to hide his illness will not be able to pass the commission by learning the location of the signs on the indicator table.

Interestingly, the famous artist suffered from color blindness I.E. Repin. The fact is that he did not have the disease hereditary nature, but was purchased due to destruction of the retina. As a result, Repin's perception of blue and yellow flowers. This happened at the artist’s old age, so the disease did not greatly affect his fate.

Limitations in life and professional activity

IN modern life a colorblind person faces limitations related to:

with control vehicles;
With dispatch work, where it is necessary to constantly monitor various color signals;
With fine arts , including in the field of landscape design and floristry such as the ability to make bouquets;
With architecture and design various objects;
With chemical industry;
With aviation(ban on piloting aircraft);
with some medical professions ;
With military service in any branch of the military.

In science there are no direct prohibitions on pursuing any field of study, but the colorblind person himself can't be:

art critic;
chemist;
biologist;
geographer

A complex system for recognizing color blindness is aimed, first of all, at preventing people with color perception problems from entering professions where their vision defects may create emergency and dangerous situations.

Reference. Everyone who is going to get a driving license is tested en masse for color blindness, but some colorblind people get their license for driving Vehicle they still can.

Only those who suffer are denied the right to drive achromatopsia. This genetic disease, which is characterized not only lack of color perception, but also nystagmus, day blindness, strabismus, decreased visual acuity.

In all EU countries, except Romania, color blindness is not a basis for restrictions when issuing driving licenses.

Useful video

A video that talks about color blindness: how different the vision of a sick person is, why this retinal defect is more common in men, how it is treated and whether there are color blind people among animals.

The term color blindness combines several types of visual impairment associated with the inability (or reduced ability) to perceive one of the primary colors. Objects painted in this color are seen as gray by a colorblind person. Rarely does a complete color disorder occur, in which a person does not distinguish colors and shades at all.

Congenital color blindness is difficult to diagnose; many people become aware of it in adulthood.

The most common form of color blindness is an insensitivity to one of the three primary colors - green, red or blue. Most often, there is slightly impaired color vision and an inability to distinguish between green and red. Less commonly, there is difficulty identifying green and blue. Complete absence color vision - color blindness is an extremely rare diagnosis (less than 0.1% of the world's population).

By code ICD-10 color blindness (color vision anomalies) has an index of H53.5.

Medical history

For the first time, inadequate color perception was studied and described by the English scientist John Dalton. He himself was a carrier of such a pathology and did not suspect about it until he was 26 years old. Dalton could not distinguish red from green. In his case, the disorder was caused by a genetic predisposition, since he sister scientist and two brothers experienced the same symptom. In 1794, the researcher published a work on color vision disorders and introduced the concept of “color blindness,” naming the disease in his honor.

How does the human eye distinguish colors?

The generally accepted theory states that the retina contains photosensitive receptors, containing specific nerve cells- cones and rods. Depending on the color-sensitive pigment contained in the cones, these cells are divided into 3 types: those that perceive red, blue and green. This is the basis of the spectrum, all other colors and shades are obtained by mixing these three.

The rods are responsible for black-and-white vision; if the cones are completely non-functional (in complete color blindness), a person sees the outlines of objects due to the receptors of the rods.

Cones respond to light reflected from the surface of objects. The angle of reflection and wavelength determine the green, red or blue spectrum. The signal from the receptors enters the brain, so a person perceives the color of surrounding objects.

Pathology appears if one or more pigments responsible for normal functioning visual receptors. Sometimes the retina has all the necessary pigments, but they are not enough for correct color perception.

Causes of color blindness

There are 2 main causes of color blindness: heredity and acquired dysfunction of color receptors. Initially it was known only hereditary form, but later, with the development of ophthalmology, it became clear that injuries to the eyeball, some diseases and even medications can disrupt the perception of colors.

Hereditary color blindness

Hereditary color blindness is associated with a defect in the X chromosome, which contains the genes responsible for the color-sensitive pigment in the cones in the retina.

In cases where color blindness is a hereditary pathology, color perception is equally impaired in both eyes. The disorder does not get worse with age, but it does not go away either.

The gene for color blindness can be passed on through generations, manifesting itself in grandchildren or great-grandchildren. To make sure there is no genetic predisposition to impaired color vision, you can take a DNA test. This method is applicable in cases where conventional visual tests cannot be used, for example, for newborns and children in the first years of life.

Acquired color blindness

Different types of color blindness result from:

eye diseases affecting the retina and optic nerve;
complications from diseases nervous system;
against the background of diabetes;
mechanical injury to the eyeball;
damage to the retina by ultraviolet radiation;
pathological changes associated with age;
taking certain potent medications.

Often acquired color vision deficiency manifests itself in only one eye if it is caused by injury or illness. This type of color blindness progresses over time, but in some cases it is curable. Among acquired color perception disorders, the most often observed is a failure in the blue part of the spectrum, when a person cannot distinguish between shades of yellow and blue.

Types of color blindness

The classification of types of color blindness (color vision pathologies) is based on which of the primary colors the patient does not see or has difficulty distinguishing.

Protanopia(from the Greek protos - first, since red is conventionally considered the first color) - impaired ability to see red. This genetic mutation is more common than others. People with protanopia, looking at red objects, see them as brown, dark gray, black, and less often dark green. They perceive green as light gray, yellow or light brown.

Deuteranopia(from the Greek deuteros - second) - pathology in the green region of the spectrum. Instead of green, a person with deuteranopia sees light orange or pink, and perceives red as brown.

Tritanopia(from the Greek tritos - third) - allows you to see red and green with all their shades, which replace the blue part of the spectrum. The inability to perceive blue and violet is not the only defect in tritanopia - the pathology affects the functioning of the rods and leads to the absence of twilight vision.

Color blindness can be classified according to the degree of color vision impairment, depending on whether the pigment in the cones is completely absent or its amount is only limited and insufficient for full bright vision.

Normal perception of primary colors is called trichromacy. A person who can distinguish all colors, but they appear faded and lack sufficient contrast, is diagnosed with abnormal trichromacy. If vision in a certain part of the spectrum is impaired, but not completely absent, the mutation is named according to the color affected: protanomaly, deuteranomaly or tritanomaly.

Dichromasia assumes that the eye distinguishes two primary colors and does not perceive the third, replacing it with shades of the first two. Within the framework of dichromasy there are protanopia, deuteranopia and tritanopia.

Man with monochromasia vision distinguishes only one of the primary colors. This mutation is often accompanied by photophobia and.

Achromasia(color blindness) – a rare event associated with the lack of pigment responsible for color vision. The world in the eyes of a person with achromasia looks black and white with shades of gray and is completely devoid of other colors.

Sometimes nature compensates for the inability to see one color with a more subtle perception of another. For example, people with protania can see more shades of green than is possible with full trichromatic vision.

Color blindness in women

Women are susceptible to hereditary color blindness 20 times less often than men. The statistics are that color blindness in women with impaired color perception occurs in approximately 0.5%, while in men it is 5-8%.

It's all about the set of chromosomes: women have two X chromosomes, so even if one of them carries the color blindness gene, the second compensates for the defect. In this case, the pathology will not manifest itself, but will be passed on to the son or daughter. Men have only one X chromosome, and, accordingly, there is no reserve to replace a gene with a mutation.

A boy will most likely have impaired color perception if one of the mother's X chromosomes contains this pathology. Your son is less likely to be born colorblind if genetic predisposition Only my father has it. For pathology to manifest itself in a girl, a mother and father with hereditary color blindness are needed. This combination is quite rare.

Acquired color vision deficiency can be equally likely to appear in a man or a woman, since it is not tied to the chromosome.

Color blindness in children

Congenital color blindness is difficult to diagnose in childhood due to the lack of external clinical symptoms. Many colorblind people learn about their pathology in adulthood completely by accident or during a specialized medical examination. How do you know if a child is color blind?

Watch him carefully while drawing, working with colored paper or plasticine. The reason to check your baby’s color vision is the presence of the gene responsible for color blindness in one of the parents.

Impaired color vision, especially if parents do not know about it, complicates the child’s life. Inadequate perception of colors can negatively affect academic performance, team relationships, and ultimately, inner world and self-esteem. Without proper explanation from adults, a generally insignificant pathology creates a lot of problems for the baby.

Caregivers and teachers should be warned about color blindness. This will help to avoid awkward situations with visual materials, and not to use colors and combinations that are inaccessible to the baby’s vision. A child with color vision impairment should sit at a desk that is not directly exposed to sunlight from the window.

The smallest colorblind child must be explained as early as possible that he sees the world differently from other people, but this feature does not make him worse than others.

Difficulties in diagnosing color blindness in children

Why does children's color blindness often escape the attention of parents and teachers? The fact is that a child is able to truly distinguish colors by the age of 3-4 years. While the names of flowers are explained to him from the age of 1.5-2 years. “This cube is blue, and this one is red.” “The grass is green, the dandelions are yellow.” The baby remembers what it calls this or that color and uses the memorized name. How he actually sees what he calls red or green, adults cannot know.

To check color perception, you need to watch a child when he draws from life or tries to convey the surrounding reality through other types of creativity. The easiest way is to ask your child to draw a landscape outside the window, flowers in a vase or loved ones cartoon characters. Based on the results, you can evaluate how adequately he perceives the colors of surrounding objects. For example, a clear sign color blindness will be the replacement of red with green or brown. However, such a home test cannot be considered reliable, because there is a risk that the child selected colors based on his own ideas about beauty or guided by imagination.

If your baby systematically replaces one color with another, you should consult an ophthalmologist. Only a doctor can diagnose color blindness based on special tests.

Color blindness test

The most common and effective test for color blindness is performed with polychromatic tables E.B. . The method was developed in the mid-twentieth century and remains the most effective today. The main test set includes 26 tables with depicted numbers of different colors; sometimes a set of 48 tables is used if high diagnostic accuracy is needed.

Tables consist of small circles different sizes. On a background of circles of one color, numbers, geometric shapes and chains are drawn in circles of another color. A person with full color vision sees contrasting images on the tables. A colorblind person can distinguish colors on some tables, and drawings made in an inaccessible color seem monochrome to him.

For accurate diagnosis, special conditions are needed:

daylight;
lighting should not be too bright or blinding;
the light should come from behind the patient;
You should not put pressure on a person during the test - results under stress can differ greatly from color perception in a state of rest and tranquility.

Each chart is shown at eye height approximately 1 meter from the patient. 5-7 seconds are allotted for one image, then it is removed and the one who takes the test reports what he saw.

For home check color vision table Rabkin you can use the online table. But you cannot rely on the test results from the screen of a PC or mobile gadget, since it is affected by the brightness and resolution of the monitor. If the test indicates impaired color vision, you need to contact an ophthalmologist to clarify the diagnosis.

In addition to the tables edited by Rabkin, there are tests for color recognition by Ishihara, Stilling and Yustova. They work on the same principle as the test described.

In some cases, the Holmgren method is used to diagnose color blindness, based on the need to distribute skeins of multi-colored yarn into the three main colors of the spectrum.

Color vision impairment can be determined spectral method using special equipment. This method is used in situations where the pigment method (based on the patient’s visual perception) does not work. For spectral diagnostics, the Rabkin spectroanamaloscope, Nagel, Girenberg and Ebney apparatuses are used.

Treatment of color blindness

Congenital color blindness associated with genetic mutation, incurable. In some cases, color perception can be corrected with professional glasses or lenses. The effectiveness of this approach to solving the problem directly depends on the specific type of pathology.

Acquired vision defects can sometimes be treated. Great importance has a cause for the pathology. Only a qualified ophthalmologist can give a reliable opinion on this matter. Depending on the factor that provoked the disorder, treatment is prescribed. So, if color blindness appeared as a result of the action of medications, their use should be stopped, and there is a possibility that the ability to distinguish colors will be restored.

Treatment of color blindness folk remedies impossible!

When the color receptors are affected by cataracts, glaucoma or other eye diseases, it is hoped that after surgery the ability to distinguish colors will return. When age-related changes and clouding of the eye lens, loss of color vision is irreversible.
Scientists are exploring the possibility of correcting mutations at the gene level, but so far such techniques have not left the laboratory doors.

Color blindness glasses

The principle of action of glasses against color blindness is that they dim bright light, since cones are more sensitive in dim lighting. These corrective glasses look like regular tinted glasses, but are additionally equipped with shields on the sides.

TO the latest developments include glasses with high-tech multi-layer lenses, created in the USA. Such optics can almost completely eliminate mild forms of pathology and restore a person’s ability to distinguish between the colors of the red and green spectrum.

EnChroma has achieved outstanding success in the field of color perception correction. Initially, her profile was research into the possibilities of creating professional equipment for surgeons. Visors should enhance color vision, helping the doctor during surgery. EnChroma's colorblind technology is designed to transmit and enhance primary colors, while blocking shades that impair color perception.

Color blindness and driver's license

The difficulties that colorblind people encounter while driving, and the danger of such a situation for others, were first noticed in 1875. Then there was an accident in Sweden railway. During judicial trial It turned out that the driver responsible for the incident suffered from color blindness and did not see the color red. Since then, the test for color blindness has become prerequisite to obtain permission to drive a vehicle. The photo below shows how a suffering person sees a traffic light various disorders color perception.

Today in the European Union, people with impaired color vision have the opportunity to obtain a driver's license on an equal basis with everyone, but cannot work in the field of commercial transportation or as public transport drivers. The situation is similar in the Russian Federation: a colorblind person can get a license of category A or B, but it will be noted that he does not have the right to work as a driver. In some countries, for example, Romania and Turkey, colorblind people are prohibited from driving.

What difficulties do colorblind people face?

In society, approximately 7-9% of people have some kind of color perception disorder. In addition to restrictions on driving vehicles, they are subject to a number of prohibitions related to their choice of profession. Colorblind people cannot work as chemists, surgeons, pilots, sailors, and some military specialties are closed to them.

In everyday life, a person is surrounded by great amount color signals. And speech in in this case not about traffic lights, since they are uniform, and colorblind people simply remember that the light of the top bulb means the need to stay in place, and the bottom one - to move forward. There are a lot of signs, signs and indicators that make life difficult for people with impaired color vision.

These days, more and more attention is being paid to the specific needs of colorblind people. Some sites and mobile applications They are making an additional version for the visually impaired, and recently versions adapted to color perception colorblind. Digital content creators ensure that the color combinations used are comfortably perceived by users with various pathologies vision.