Part 1

Improving your ability to see in the dark

Use your chopsticks. It takes 30 to 45 minutes for the rods to adjust to the change in light around you. Rods perceive only black and white colors and have low clarity, but they are extremely sensitive under night lighting conditions.

• Photosensitive pigments are light-sensitive substances found in rods and cones that transmit visible images to your brain. Rhodopsin is visual pigment, contained in rods and responsible for night vision.
• Your eyes' ability to adapt to darkness depends on some things you can't control, like your age, traumas suffered or eye damage, as well as any existing eye diseases.
• To see in the dark, you must know how to increase the sensitivity of your rods and force your eyes to adapt more quickly to sudden changes in light.
• In dim lighting, avoid looking directly at the light source. This way you use your rods rather than your cones, which are activated when your eyes look at a dim light source. This technique is often used by astronomers.

1. Wear dark or red-tinted glasses. Rods are not sensitive to red light, so wearing these glasses for 20 to 30 minutes before entering a dark room will help you recognize movement inside more quickly.

   • By blocking the entire visible spectrum except red, these glasses will allow your rods to adapt to a kind of darkness before you're actually in it.
   • This method is used by pilots when they do not have time to be in complete darkness before a night flight.

2. Don't look at the light source. Light sources will cause your pupils to contract, thereby impairing your night vision.

   • The pupil is similar to the aperture of a camera, it contracts and dilates depending on the amount of light entering the eye. The brighter the light, the narrower the pupil becomes. In low light conditions, your pupil will dilate greatly to absorb as much light as possible.
   • By pointing your eyes toward the light source, you increase the time it takes for your eyes to adjust to the low light.
   • If you cannot completely avoid bright light, close or close one eye completely, or look to the side until the light source disappears from your field of vision.

3. Improve night vision while driving. Before you get in the car, take steps to improve your vision for night driving.

   • As mentioned above, try not to look directly at the approaching light source. If another car comes around a corner with its high beams on, close one eye to prevent temporary vision loss in both eyes and to return to normal night vision more quickly.
   • Look at the white line on the right, which is on your side of the road. This will allow you to stay in a safe direction, notice moving objects in your peripheral vision, and avoid being blinded again by the high beams of oncoming cars.
   • Reduce the intensity of the instrument panel lighting to low, but safe level to help your vision during night trips. Also use night mode on your rearview mirrors. This will reduce the bright light from Vehicle, following you.
   • Wash your car's headlights, wipers and windshield regularly. At night, spots on the windshield can become sources of bright light.
   • Carry out timely Maintenance your car, including adjusting the headlights and fog lights. Even a slight shift of one or two degrees can prevent other drivers from experiencing vision problems as a result of your headlights.

4. Let your eyes get used to the darkness on their own. The best way learning to see in the dark means allowing your eyes to slowly adapt to the darkness by remaining in complete darkness for 20-30 minutes.

5. Engage peripheral vision. Each of your eyes has natural blind spots, which can make it much more difficult to navigate in the dark while you're trying to focus your eyes.

   • As you move through a dark room, try to focus on an object away from you or in close proximity to the direction you are moving. Through your peripheral vision, you will be able to notice the movement and shape of an object better than by trying to see it directly.
   • Peripheral vision is activated large quantity rods, which play a key role in orientation in the dark, determining the shape of an object and detecting movement.

6. Go lower to distinguish the silhouettes and use the effect of contrast. Remember that your sticks are color and clarity blind and are your guide in the dark.

   • The night sky is a wonderful source of light. Once low enough, the light from the night sky or from a window provides enough contrast to make the rods work easier in your eyes.
   • Some martial arts teach you to stay as low as possible, using the sky to illuminate objects and opponents so you can more easily make out their silhouette.
   • Although rods are more sensitive to light than cones, they can only distinguish between black and White color and the image is of poor quality, contrasting the available light source behind the objects.

7. Massage eyeballs. Close your eyes tightly and press lightly with your palms. .

   • After about 5-10 seconds, the darkness surrounding you will turn white for a few seconds. When whiteness is replaced by black again, open your eyes and you will see much better in the dark.
   • Rumor has it that special forces soldiers use a similar technique - when they find themselves in the dark, they close their eyes tightly for 5-10 seconds. Although the effectiveness of this method has not been proven by the scientific community, it can still help someone.

8. Use all your senses to “see.” In a dark room, step carefully until your eyes get used to the darkness.

   • Keep both feet on the ground, extend your arms forward and move slowly. Watch closely for changes in sound, which may indicate the presence of a door, hallway, or window nearby. Fumble with your hands in front of you to avoid colliding with a tree or doorway.

9. Learn to navigate by sound. Researchers have made great strides in working with blind people. They have developed the ability to make clicking sounds with their tongue, called click sonar. It's similar to the echolocator they use the bats.

   • Using click sonar, you can quite accurately determine the location of objects in front of you and around you. An experiment was conducted in which a woman made clicking sounds with her tongue to “scan” the space in front of her until she was able to find a saucepan that another person was holding. With a couple extra clicks, she was able to determine the type and shape of the lid on the pan.
   • Another click sonar expert is able to ride a mountain bike through difficult terrain and navigate around all obstacles without any problem.
   • Experts in the click sonar technique claim that every person can develop this ability.

   Part 2

   Protect and improve your vision

   1. Wear Sunglasses V daytime. Several hours under the influence of bright sunlight And ultraviolet radiation may impair your ability to adapt to darkness.

      • For every 2-3 hours spent under the bright sun during the daytime without sunglasses will slow down your adjustment to darkness by about 10 minutes.
      • Moreover, in addition to slower adaptation to darkness, the quality of night vision also decreases. For example, 10 days of exposure to bright sunlight without protective glasses can reduce your ability to see in the dark by half.
      • Over time, your rods, cones, and light-sensitive pigments will return to normal. The duration of exposure varies for each person.
      • Use neutral gray sunglasses that allow 15% of visible light to pass through.

   2. Turn down your computer's brightness. If you work at night, set your monitor brightness to its lowest setting.

      • If you are in a dark room but looking at a bright screen, the effectiveness of your night vision will be significantly reduced.
      • Some programs help you adjust the screen brightness depending on the time of day.

   3. Give your eyes a rest. Take frequent breaks between sitting in front of the monitor, reading books and other cases of prolonged concentration.

      • Your eyes need frequent rest. After every 20 minutes of intense work, especially in front of a computer screen, take a break and look into the distance for 20 seconds. This will allow your eyes to refocus.
      • After every two hours of concentrated work in front of a computer screen or other task that requires close attention, rest your eyes for 15 minutes.
      • Keep your eyes from straining by taking a five or ten minute nap in the middle of the day. Close your eyes and massage them gently. You don't have to go to bed to rest your eyes.

   4. Train your peripheral vision. Using your peripheral vision is essential to improving your ability to see in low-light areas.

      • Peripheral vision is your ability to notice movement at the edge of your visual field using the rods in your eyes.
      • The development of peripheral vision is effective way Increases visibility in low light.
      • Although training your peripheral vision takes a lot of time and effort for most people, it can help you see much better in the dark.
      • By doing eye exercises to improve your vision (including peripheral vision), you will begin to see better in the dark.

   5. Try an exercise that is often used in sports training. Improving peripheral vision is useful in many situations, including sports.

      • For this exercise you will need a regular one-color straw. Draw a black stripe around the center of the straw.
      • Give the straw to your partner and move 0.3-0.6 meters away from him, taking a toothpick in each hand. Your partner should hold the straw horizontally.
      • Look at the black line and notice the ends of the straw using your peripheral vision.
      • Concentrate on the black line. Try inserting toothpicks into the holes on both ends of the straw while keeping your eyes on the black line.
      • Once you get the hang of it, you can increase the difficulty of the exercise by using two straws connected to each other.

   6. Focus on your peripheral vision. Another way to develop your peripheral vision for better night vision is to focus your attention on it and use it more often in daylight.

      • Sit somewhere (preferably outside) where you can watch a lot of different things. Focus on the object that is directly in front of you.
      • Make a mental list of everything you see around you (both movable and non-movable objects), without distracting from the central object. Look away and look around to see what you might have missed. Mentally note how far from the center you could recognize things around you.
      • Repeat this exercise, but in a different place, and try to expand the area within which you are able to recognize surrounding objects.

   Part 3

   Diet change

   1. Eat blueberries. Blueberry is a plant that is used in the creation various types medicines.

      • Research has shown that blueberries may have some effect on retinal-related eye problems.
      • Most prospective studies support the use of blueberries in cases associated with retinal changes due to such medical conditions like diabetes and high blood pressure.
      • Blueberries are believed to improve night vision, although research results are conflicting. Some evidence suggests that blueberries have positive impact to improve night vision, while others do not support these claims.
      • When it comes to improving night vision, the latest evaluation of blueberries puts them in the same category as other "possibly effective" remedies.
      • Blueberries are not easy to find in their raw form, but they are freely available in the form of extract, jam or jelly. Follow package directions to determine how many blueberries you should consume per day.

   2. Consume more vitamin A. One of the first symptoms of vitamin A deficiency is night (or night) blindness.

      • Also in Ancient Egypt It was discovered that to treat night blindness you need to include liver in your diet, which was later found to contain a large number of vitamin A.
      • A lack of vitamin A causes the surface of the cornea to become very dry, which in turn leads to clouding at the front of the eye, ulcers on the surface of the cornea, loss of vision, as well as retinal damage and problems with the mucous membrane of the eye.
      • Excellent sources of vitamin A include foods such as carrots, broccoli, pumpkin, cantaloupe, fish, liver, fortified cereals, dairy products, cabbage, blueberries and apricots.
      • Although increasing your intake of foods rich in vitamin A may be beneficial, research in this area has shown that dietary supplements provide significantly more vitamin A. Moreover, overconsumption These products will not improve your vision.
      • Vitamin A can be purchased in tablet or capsule form, and dosages are given in micrograms or units. The average recommended dose of vitamin A for an adult is 800 to 1000 micrograms, or 2600 to 3300 units per day.
      • The protein rhodopsin, located in the eyeball, breaks down into retinal and opsin under the influence of light and is synthesized back in the dark. Severe vitamin A deficiency can lead to night blindness, but supplemental vitamin A will not improve vision.

   3. Increase your intake of dark green and leafy vegetables. As for improving night vision and vision itself, greatest benefit can be achieved by focusing on the foods you eat.

      • Kale, spinach and kale are rich in nutrients, which protect the eyes by filtering out certain light waves that can harm the retina.
      • These products also protect your eyes from certain degenerative processes, like dystrophy macular spot due to aging.

   4. Eat more healthy fats. In particular, consume more foods containing omega-3 fatty acids.

      • Omega-3 fatty acids are found in fish, especially fatty varieties such as salmon and tuna, as well as kale, vegetable oils, nuts (in particular, in walnuts), flax seeds, linseed oil and leafy vegetables.
      • Omega-3 fatty acids combat macular degeneration and help maintain eye health, good vision and save them from dryness.
      • According to one study, patients who ate fatty fish once a week, the risk of developing neovascular macular degeneration was halved. If you consume enough omega-3 fatty acids during long period(over 12 years), the risk of developing this disease will decrease even more.

How often does a situation occur when we find ourselves in complete darkness? Most likely quite rare. But even those few cases that happen to us give us the idea that why can't people see in the dark?

Moreover, our ancestors were forced to be in darkness and twilight for almost half the day. This means there must be a solution to this problem.

In fact, there are no animals that can see in complete darkness. But the amount of light needed to distinguish the outlines of objects is required for nocturnal animals, but much more is needed for humans.

We know many animals leading night look life. It was they who pushed scientists to search for a solution. After all, having learned how the structure of the eye, for example a cat, differs, we can draw a conclusion about what a person lacks for night vision. Scientists have been searching for an answer for a long time and conducting all kinds of experiments.

In the course of such studies, a discovery was made: it turned out that nocturnal animals can see in the dark thanks to the original “packaging” of DNA located in the nuclei of the light-sensitive rod cells of the retina.

In humans and other animals unadapted to darkness, the light falling into the eyes is scattered, but in cats these cells focus the light. Thanks to this, even very weak light passes deep into the layers of the cat's retina.

A large number of such lenses in the retina, focusing light fluxes, help animals distinguish weak light, just a few photons.

Moreover, this structure of unusual DNA packaging does not congenital feature, but acquired. For example, newborn mice do not have the ability to distinguish objects in the dark, but after a couple of weeks this ability develops.

This means that when you change your lifestyle, the eye can adapt to very low light. Of course the person won't see better than cats, because there are other factors, for example visual acuity, but if long years he will live in the twilight, then he will see everything much better than you and me.

According to scientists, during the course of evolution, animal eyes have adapted more than once to different conditions lighting.

By the way, some diurnal animals do not have any adaptations for night vision. For example, in pigeons the eye consists only of “cone” cells, and there are no “rod” cells at all. This is why many birds are easily calmed by covering the cage.

If you often find yourself in relative darkness, and also if you have free time, you can start training your eyes. Of course, you shouldn’t sit in complete darkness for days and wait for your eyes to adapt. It won't happen so quickly; it will take years. But speed up getting your eyes used to the dark You are quite capable.

A few simple rules will help you with this:

1. Eat right. There is a substance that is indispensable for the eyes - beta-carotene, it is a kind of energy booster for the retina. It is found in carrots, tomatoes, pumpkins, and persimmons. Another useful product is zeaxanthin, it is found in spinach and eggs. Zeaxanthin is responsible for the sharpness, contrast and saturation of our visual image.

2. If we prepared correctly by eating a bunch healthy products, it’s worth starting testing. Before entering a dark room, cover one eye with your palm. He will get used to the absence of light and will not be blinded by the darkness, as open eye. This means you will immediately see objects in the room. Don't close both eyes, it's less effective.

3. There is such a peculiarity in the dark - if we look at an object directly, it blurs, but if we look with peripheral vision, objects are visible much more clearly. This happens because when we look directly, we look with “cone” cells, and when we look sideways, we use “rods”. And it is the sticks that are more adapted to low light.

And a few more words about psychological factor. The more afraid you are of the dark, the worse you will see in it, since your brain will not be busy adapting the eye, but with the nightmares that appear in your imagination. Therefore, do not perceive darkness as a hostile phenomenon.

Who sees in the dark?

We have already touched on the phenomenon of cat vision. All members of this family have such night vision.

Owls, many rodents, dogs and other nocturnal animals can navigate well in the dark.

In most nocturnal animals, vision is replaced by hearing. It has been scientifically proven that the hearing of such animals is much sharper than that of humans.

And such inhabitants of the twilight as bats even “see” through hearing. They make sound all the time while moving, at frequencies that are not audible human ear. And they listen to how this sound is reflected from objects. And then they draw conclusions about where the object is, what is the distance to it and what shape it is.

This is how amazingly everything works in our world. Even practically blind animals do not remain helpless.

Hemeralopia in equally representatives of both sexes suffer, but during menopause in women, when endocrine changes occur in the body, they are at risk of night blindness slightly higher. Interestingly, Australian Aborigines are naturally endowed with increased vigilance, especially at night. Studies show that the visual acuity of these people reaches 400%.

The peoples of the North also see better in the dark. This ability was developed, because in the North sunny days significantly smaller, so their eyes have “historically” adapted to such conditions. In winter, during short daylight hours, the problem of hemeralopia becomes especially acute.

Reasons for the development of hemeralopia

According to numerous studies, it has been proven that hypovitaminosis can cause impaired twilight vision. A lack of vitamin A can cause: dryness of the conjunctiva, its redness and thickening, decreased secretion of the lacrimal glands, clouding of the cornea and corneal hyposthesia, etc.

As is known, vitamin A is a direct participant in the mechanisms of photoreception. With a lack of vitamin A, the retinal rods are destroyed, and dysfunction of the retinal rods is the first sign of hemeralopia. Reveal this pathology can be done using dark adaptometry, electroretinography or scotometry.

Among possible reasons doctors call hidden diseases body: general exhaustion caused by hard work or long-term illness, pregnancy, anemia or.

Often the disease is associated with hereditary factors, but can also occur as a result of measles or chickenpox suffered in childhood. Often the cause is malnutrition, anemia, exposure to toxins, diseases, optic nerve, liver, chronic alcoholism, solar. One of the main reasons for the development of hemeralopia is considered to be a lack of vitamins A, B2 or PP in the body. Congenital hemeralopia manifests itself in childhood or early adolescence.

Diagnostics

Treatment of the disease

Experts divide hemeralopia into two types: congenital and acquired. Congenital hemeralopia, unfortunately, cannot be treated. In other cases, vitamin preparations are prescribed and treatment is carried out for the eye disease that caused the development of hemeralopia.

The causes of hemeralopia can be diseases such as myopia, glaucoma, cataracts, and accordingly the treatment will be different. In cases where hemeralopia is caused by myopia (myopia), treatment is carried out either by laser correction myopia, or through refractive surgery (scleroplasty, lens replacement, etc.).

If the root cause is glaucoma or cataract, then antiglaucomatous surgery, cataract extraction or phacoemulsification is performed. In cases of retinal detachment, laser coagulation. Essential hemerolopia is caused by a deficiency of vitamins; treatment consists of normalizing nutrition and taking vitamin complexes And food additives for the prevention of eye diseases.

Part vitamin preparations, which are prescribed for the treatment of essential hemeralopia, include beta-carotene (is a provitamin A that does not cause side effects in the form of hypervitaminosis A), vitamin C (a natural antioxidant that helps strengthen the blood vessels of the eye), vitamin E, vitamin A, lutein, as well as trace elements: selenium, copper, zinc, taurine. Such complexes are the main treatment for essential hemeropia and help change the risk of developing eye diseases.

It should be said that treatment differs in each specific case. Therefore, you first need to find the cause of the disease and understand what the body lacks. Patients with hemeralopia are advised to be examined to determine the level of retinol, carotene, and vitamin A in the blood. If the concentration of these vitamins is reduced, corrective treatment is prescribed. Consultations with specialists of other profiles (gastroenterologist, endocrinologist) are recommended.

You should not try to treat hemeralopia on your own - it is impossible. But preventive measures warnings of this disease It’s entirely possible to do it yourself. This is not at all difficult and will only require inclusion in daily diet foods rich in vitamin A (such as: carrots, spinach, tomatoes, salads, green onions, blackberries, apricots, black currants, blueberries, gooseberries, milk, butter, cod liver, cheese, cream, fish roe, egg yolk). Millet is especially useful among cereals.

People over 50 years of age often suffer from hemeralopia. For example, the quantity car accidents, the culprits of which are drivers with this disease, is growing rapidly. Doctors warn that a person with night blindness simply does not notice the dangers on the road if he drives at dusk, and in the light of oncoming headlights he generally loses orientation.

Bright light blinds him, and he cannot adapt to the darkness (or adapts slowly). That is why German ophthalmologists put forward a proposal for checking the vision of motorists in mandatory check whether they have hemeralopia.

It is worth mentioning that false hemeralopia also exists, although not all experts agree with this definition - after all, it either exists or it does not. And yet, to the cases false violation twilight vision can be attributed to a temporary decrease in vision in the twilight due to prolonged intense work of the eyes (computer, small printed text, etc.)

Choosing a clinic to treat anyone ophthalmological disease- a responsible question that requires a balanced approach. It is worth paying attention to the level of equipment of the clinic, the professional level of the specialists working in the clinic, reviews of those people who have already been treated in a particular eye clinic.

How can you improve your vision in the dark? This question can interest everyone to one degree or another. Some - the need to get from work to dark time days, others - by the specifics of the work itself, requiring special skills.

When the lights go out completely, any person loses the ability to navigate for some time, even in his own apartment. But there are techniques that can help you significantly improve your ability to see in the dark.

How to improve vision in the dark? This adaptation takes time. Adaptation occurs due to the photoreceptors of the retina of our eyes, which are divided into 2 types: rods and cones. Rods are responsible for transmitting black and white and various gradations to the brain gray, they are focused on sensitivity to low intensity light in twilight and darkness.

Cones make it possible to see the world in colors, they are called apparatus day vision. At twilight, when the intensity of the light flux actively decreases, the cones stop working and the colors become indistinguishable to our eyes.

So, if you look at colored paper, at this time of day it will seem colorless and gray. Red objects will appear black. And blue objects will seem light. These are examples of a Purkinje shift, which is explained by a change color perception in the dark by connecting rods to the visual work.

These sticks can only provide us with a dull and colorless picture. Since cones only work when there is a sufficient level of illumination, we see colors only during the day, and at night, as they say, all cats are gray. To understand how to improve vision in the dark, you need to know the basics of the process of restructuring night vision or dark adaptation.
Wands are not able to instantly work at maximum efficiency. They contain the main pigment - rhodopsin (visual purple), the amount of which is gradually restored in the dark and completely disintegrates in bright light.

Knowledge of how to improve vision in the dark and adapt it to night vision depends not only on practical classes, but also from academic knowledge of the structure of the eye.

Therefore, when entering a closed dark room with bright light, our eyes practically cannot see. The more visual pigment accumulated, the better person navigates in the dark.

Eye habituation occurs from the moment a person is immersed in darkness and increases greatly during the first 15 minutes. Maximum adaptation to darkness is achieved in approximately 1 hour.

To increase the speed of dark adaptation in the twentieth century, the Institute of Psychology of the Academy of Pedagogical Sciences of the RSFSR developed effective techniques that are still relevant today.

No.	How to improve vision in the dark	Practical examples
1.	Breathing exercises	Sharp deep inhalations and exhalations that begin after a full exhalation;
2.	Thermal action	Washing cold water, compresses on the back of the head, wiping the face;
3.	Taste irritants	Eating sweets, including small amounts of sugar, or sour;
4.	Muscle activity	Light physical warm-up;
5.	Vitamin A intake.	Retinol acetate is several times higher than the daily dose.

Using these methods to improve visual sensitivity in the dark, periodadaptation of a trained person is reduced from 60 minutes. up to 5 min. And for healthy people And those who have visual impairments, these tips for improving night vision will be equally useful.

Secrets of red

To activate cones that are inactive in the dark, you need light of sufficient brightness. The red spectrum is low-frequency, it has low intensity and brightness, longer length direct waves and weak scattering of light to the sides.

It is unable to awaken sleeping daytime photoreceptors, and, at the same time, it is not able to be distinguished by rods, which systematically continue to accumulate visual pigment to improve night vision. Even during the Second World War, American guards used tight-fitting eye guards. red glasses, which were put on an hour before leaving the room in an unlit area.

In this way the sticks could freely naturally accumulate visual pigment in a brightly lit room and be fully prepared for night duty. This example how you can improve your vision in the dark without extra effort is still relevant today.

Half an hour before plunging into darkness, you can put on red-tinted glasses, which blocks any color spectrum other than red. This method is used by pilots before a night flight. The same principle is used to use a red flashlight and red lighting in security rooms or the X-ray technician’s room.

Night photoreceptors are most sensitive to short-wave radiation. It is for this reason that blue objects in the dark appear much lighter than red ones.

To better navigate in the dark, you need to try to use your peripheral vision. and embrace the whole picture, looking a little past it. There is no need to peer into a specific object, trying to see it.

All the same, you won’t be able to see anything in this way, since night photoreceptors are concentrated more at the edges of the retina and are completely absent in the central fovea. Therefore, even in conditions of accumulation of a sufficient amount of visual purple with direct tunnel vision, there will be a black spot, covering the object.

It wouldn’t hurt to sometimes close your eyes for a few seconds, giving eye muscles a little rest.

Explicit and a clear example The need to use peripheral vision in the dark is to observe the stars in the sky. Sometimes peripheral vision notices a dim star, but when you look directly at it and try to see it, it dissolves into the darkness.

Turning your gaze to other stars, the inconspicuous star appears again in your field of view. Brighter blue, yellow or reddish stars that have a sufficient level of brightness are seen by humans using color photoreceptors.

Central nervous system provides the male half of the population with excellent tunnel vision: the ability to see straight ahead very far and clearly. A A woman’s brain is programmed specifically for developed peripheral vision, which allows you to cover a wide range of objects at approximately 45° in both directions.

Therefore, the peripheral vision of many representatives of the fair sex reaches 180°. This is another reason why a man notices and directly follows an interesting stranger far away, and his girlfriend or wife standing next to him will always see it.

The peripheral vision of humans and most animals differs dramatically in the range of coverage.

Medical diagnosis of peripheral vision is very important if you have certain diseases. So, Decreased vision during twilight is an indicator of vitamin A deficiency, one of the factors in glaucoma and retinal diseases.

How else can you improve night vision in the dark?

The contrast effect is well suited for this purpose, when vision periodically concentrates either on the darkest place or on lighter objects. Wherein Don’t focus your gaze on a specific light source so that flare does not occur and the already accumulated visual purple does not disintegrate in the light.

It will also help to adapt well by alternating your gaze from distant objects to nearby objects. A good contrast will be the incident light from the windows in the distance. or stars in the night sky.

Under changing lighting conditions, a person's eyes adapt faster when immersed in complete darkness from twilight than from bright light. At the same time, changes in eye sensitivity specifically during dark adaptation from bright light and vice versa - from complete darkness to bright light - have been more fully studied.

The addiction process is intense in the first 15-20 minutes, and then proceeds slowly and is fully achieved in 2 hours. After the first hour, eye sensitivity increases incredibly. In order to help the eyes quickly get used to new lighting when the brightness of the light changes, the diameter of the pupil changes.

Cats are recognized masters of dark adaptation.

The maximum constriction of the pupil occurs at 1.5 mm, and the maximum magnification is up to 8 mm, so the amount of light entering the eyes can change by 30 times due to changes in the size of the pupil. In the dark, the pupil dilates in order to absorb as much light as possible and gain the ability to navigate in space.

Eyeball massage

Additional massage areas.

To improve vision in the dark, massage the eyeballs will help.

Here's how to do it correctly:

1. The massage begins with complete relaxation, preferably in a sitting position. The palms should be warmed by rubbing them together;
2. Then you need to cover your eyes with your palms and gradually increase the pressure. After 5 seconds the darkness will appear white. After completing the procedure about 5 times, you should clench your hands into fists and gently massage your eyeballs the way small children do when they want to fall asleep.

Other ways to improve night vision acuity

There are many more ways to increase your eyes' light sensitivity in the dark.

These include:

• Improved blood circulation due to chewing movements, which will make it possible to quickly improve the quality of vision in the dark;
• Staring night sky;
• Gently tapping with fingertips by closed eyelid to ensure blood flow. Then you should stretch your finger joints, focusing Special attention pads that are connected to the visual apparatus. Massaging your fingers will speed up adaptation;
• Night perception accelerates when nervous tension , however, eye sensitivity also drops sharply as energy is expended due to stress;
• To speed up dark adaptation by increasing blood flow to the brain and oxygen, the method of throwing back and sharply lowering the head is used. The head is thrown back all the way at the moment of a deep breath. After a few seconds of this position, it drops very sharply. In this case, you may experience dizziness and sparkles in your eyes, but this is not scary. Night vision will improve significantly.

When in the dark To preserve night vision and reduce the period of full adaptation, you should not look at light sources. If bright light cannot be avoided, for example, light from a lantern falls on the street, then you need to cover one eye, which will preserve the accumulated visual pigment and the ability to see well at night.

Interesting fact. Sea pirates were also familiar with the mechanisms of night vision - they covered one eye with an eye patch so as not to lose the ability to see in the dark, when descending from the illuminated deck into the dark ship's hold.

How to train night vision

A person gains the ability to hypersensitivity eyes in the dark thanks to targeted training.

They are as follows:

• In the dark, vision can be improved and adaptation time reduced, if you wear sunglasses, preferably with gray tint. As practice shows, being in the sun without sunglasses for 3 hours extends the time of getting used to the dark by 15 minutes;
• You need to train your vision using the contrast method and peripheral vision;
• Night vision is enhanced several times when sitting, therefore, when immersed in darkness, it is advisable to sit down;
• Do not underestimate the method of self-hypnosis and a responsible attitude, since, according to numerous observations of specialists, they play a significant role in adaptation in the dark.

How to gradually improve your vision in the dark by doing simple exercises? It's very simple! The main thing is to understand the mechanism of how the eyes work and train them regularly., especially if it concerns professional interests.

If you want to improve your vision in the dark, then watch this educational video on this issue:

Today, adaptation to night vision can be given to a person by chemically what is discussed in this video:

I wish you healthy vision and successful training!

During the day, in good lighting, hemeralopia sufferers do not have any complaints. Well, except that sometimes in very bright light they may develop photophobia. However, with the onset of dusk or when the room darkens, they notice that the outlines of objects become unclear and their fields of vision narrow. Color perception is impaired, especially blue and yellow colors.

Children with hemeralopia are often frightened by the deterioration of their vision in the dark.

Description

The retina of the eye contains two types of light-sensitive cells - rods and cones. Rods are responsible for black-and-white vision and enable a person to see in low light conditions, while cones are responsible for color perception. Normally, there are approximately 18 times more rods than cones, and if their number decreases or their work is disrupted, a person begins to see worse in the dark and develops night blindness.

Hemeralopia is called night blindness because those suffering from this disease, like chickens, see poorly in the twilight: that the retina of a chicken's eye consists of only cones, so birds distinguish colors very well, but see almost nothing in the dark.

Hemeralopia can be congenital or acquired. Congenital hemeralopia is caused by genetic diseases, such as hereditary retinitis pigmentosa or Usher syndrome. In this case, hemeralopia manifests itself quite early in childhood or adolescence.

Acquired hemeralopia can be either essential or symptomatic. Essential hemeralopia develops when functional disorders retina. This usually occurs with a lack of vitamins, PP, B2. The cause of such vitamin deficiencies may be liver disease, irrational and insufficient nutrition, alcoholism, diseases gastrointestinal tract, rubella, poisoning with some chemicals. This hemeralopia worsens in the spring.

A risk factor for the development of hemeralopia is age after 40 years. It is at this time that they slow down metabolic processes in the body and the nutrition of the retina deteriorates.

Diagnostics

To diagnose this disease you need to contact an ophthalmologist. The diagnosis is made based on patient complaints and research:

• perimetry (determining the field of view);
• ophthalmoscopy (detection of degenerative lesions on the retina);
• adaptometry (light perception test);
• electroretinography (study functional state retina);
• electrooculography (checking the surface layer of the retina).

In the case of essential hemeralopia, a consultation with a gastroenterologist will be required to determine the cause of the vitamin deficiency.

Treatment

Congenital hemeralopia cannot be treated.

In the case of symptomatic hemeralopia, treatment consists of eliminating the underlying disease that caused night blindness. In this case, the outcome of treatment is determined by the severity of the underlying disease. Perhaps as complete cure, and persistent loss of twilight vision.

Essential hemeralopia responds well to treatment. To do this, it is necessary to eliminate the causes of vitamin deficiency, and often it is enough to simply change the diet and quality of nutrition. Doctors recommend eating more liver, carrots, spinach, lettuce, green onions, milk, cheese and egg yolks. Apricots, gooseberries, black currants and blueberries are also useful.

Prevention

Prevention of hemeralopia involves proper nutrition and prevention of eye diseases. Ophthalmologists remind that workplace It must be well lit and, if necessary, in bright sunshine, when welding or in white snow, you must wear safety glasses. You should try to protect your eyes and head from injury.