The structure and function of the eye
Man sees not eyes as well through the eyes, from where information is transmitted through the optic nerve, chiasm, optic tracts in certain areas of the occipital lobes of the cerebral cortex, where that picture of the outside world which we see. All these organs and make up our visual analyzer or visual system.
The presence of two eyes allows us to make our vision stereoscopic ( there is to form a three-dimensional image). The right side of the retina of each eye passes through the optic nerve the “right side” of the image into right side of the brain, the left side of the retina acts in a similar way. Then two parts of the image – right and left – The brain connects together.
Since each eye perceives its “own” picture, in violation of the joint movement of the right and Binocular vision may be disturbed in the left eye. Simply put, u you will begin to double in eyes or you You will see two completely different pictures at the same time.
Main functions eyes
- opticalprojecting thesystemimage;
- system perceiving and”Coding” the information obtained for the brain;
- “Serving”systemlife support.
The eye can be called a complex optical device. His main task – “transmit” the correct image to the optic nerve.
Cornea – a transparent shell covering the front of the eye. AT it lacks blood vessels, it has great refractive power. Enters into optical system of the eye. Cornea bordered by opaque outer shell of the eye – sclera. See corneal structure.
Front camera eyes Is the space between the cornea and iris It is filled with intraocular fluid.
Iris – by form similar to circle with hole inside (pupil). Iris consists of muscle contraction and relaxation of which the size of the pupil change. She enters choroid of the eye. Iris is responsible for eye color (if he blue – means in her little pigment cells, if brown – lot). Performs that same function as the diaphragm in camera, adjusting the light flow .
Pupil – hole in iris Its size usually depends on light level. The more light, the smaller the pupil.
Lens – “natural lens” of the eye. is he transparent, elastic – can change its shape, almost instantly “inducing a focus”, for account of what a person sees well and near and away Located in capsule retained ciliary girdle . The lens, like cornea, enters optical system of the eye.
Vitreous body – gel transparent substance, located in back of the eye. Vitreous body maintains the shape of the eyeball, participates in intraocular metabolism. Enters into optical system of the eye.
Retina – consists of photoreceptors (they are sensitive to light) and nerve cells. Receptor cells located in retina are divided into two kinds: cones and sticks. AT These cells, which produce the rhodopsin enzyme, convert light energy (photons) into electrical energy of the nervous tissue, i.e. photochemical reaction.
The rods have high sensitivity and allow you to see in poor light, they are also responsible for peripheral vision. Cones, on the contrary, require more light for their work, but they allow you to see small details (responsible for central vision), make it possible to distinguish colors. The largest accumulation of cones is in central fossa (macula), responsible for highest visual acuity. The retina is adjacent to choroid but on many sites loosely. It is here that she and tends to exfoliate in various diseases of the retina.
Sclera – opaque outer shell of the eyeball, passing into front of the eyeball in transparent cornea. TO sclera fasten 6 oculomotor muscles. AT it contains a small amount of nerve endings and vessels.
Choroid – lines the back of the sclera, to it adjoins the retina, with which it is closely related. The choroid is responsible for blood supply of intraocular structures. In diseases of the retina is very often involved in pathological process. AT choroid no nerve endings, so when it the disease is not pains occur, usually signaling any malfunctions.
Optic nerve – using the optic nerve signals from nerve endings are transmitted in brain.
Gymnastics for the eyes
The first exercises for the preservation of vision were created long before our era. Yogis, creating complexes for the whole body, did not forget about our eyes. They knew that for best results, not only training, but also a good rest is needed.
The large amount of information that we “absorb” every day requires almost constant tension from our eyes. And, naturally, they get tired. Many vision problems arise precisely from overvoltage. Even a person with a “unit” needs rest for the eyes. Otherwise, after hard work, symptoms such as dry eyes , redness, and vision deterioration may appear . What can we say about those whose vision leaves much to be desired – in this case, rest is simply necessary for the eyes. It was not for nothing that W. G. Bates and his student M. D. Corbet , creating their own system for improving eyesight, relied in large part on this fact.
Exercises and relaxation for the eyes, which will be given below (this is both a yoga complex, and exercises by W. G. Bates and MD Corbet ) are quite simple and will not take much time. But … all ingenious is simple and difficult at the same time. Therefore, first try to carefully read the description of the exercise. If it is written that the movement should be smooth – this is important. If recommendations are given on how to breathe, pay attention to them. Do not forget about these “little things” and then exercise and rest will be most effective.
First – the rest. Palming
Sit up straight, relax. Cover your eyes like this: the middle of the palm of the right hand should be opposite the right eye, the same with the left hand. The palms should lie gently, do not press them firmly against the face. Fingers can cross on a forehead, can settle down nearby – as it is more convenient to you. The main thing is that there is no “crack” that lets in light. When you have verified this, lower the eyelids. The result is that your eyes are closed and, moreover, covered with the palms of your hands.
Now lower your elbows on the table. The main thing is that the neck and spine are almost in one straight line. Check that your body is not strained, and your arms, and back, and neck should be relaxed. Breathing should be calm.
Now try to remember something that gives you pleasure: how you rested on the sea, how everyone congratulated you on your birthday, the starry sky … You can do this exercise to the music. It is very difficult to consciously relax your eyes (remember that you cannot control your heart too). Therefore, you do not need to try to control your condition – it will only damage the goal of the lesson, instead think better about something pleasant.
Exercise can be performed at work, taking short breaks. Even in 10-15 seconds, your eyes will have time to relax a bit. But, of course, it will be better if you allocate at least a few minutes for relaxation.
After doing the exercise (especially if you have been doing it for a long time), gradually open your palms, give closed eyes a little getting used to the light, and only then open them.
” Nose movement “
This exercise is designed both to relax the muscles of your eyes and to relax your neck. Stress in this area disrupts the proper nutrition of the eyes (in other words, the blood supply slows down).
Exercise can be done lying down and standing, but sitting is best. Relax. Close your eyes. Imagine that the tip of the nose is a pen that you can write (or imagine that a long pointer-pen continues the line of the nose – it all depends on how you prefer, the main thing is that you and your eyes do not strain). Now write (or draw) in the air with your pen. What exactly is not important. Write different letters, names of cities and countries, a small letter to your loved one. Draw a house with smoke from a pipe (such as it was painted in childhood), just a circle or a square.
If you want to relax your eyes a little while sitting right at your workplace, you can imagine that you are not writing with a pen, but with a needle tip on the head of a pin. Then colleagues will not ask you what you are doing, because from the side of the movement of your head will be almost invisible. The staff will think that you are just sitting with closed eyes in order to relax a bit. What will happen not far from the truth. In the same way, you can relax your eyes if you return home from work in public transport.
“Through the fingers”
Relaxation of the eyes can be achieved due to the fact that you are looking, not concentrating on one thing. To relieve tension from your eyes, you are offered this exercise. It can be done sitting, lying, standing.
Bend your elbow so that your palms are slightly below eye level. Open your fingers. Make smooth turns head to the left and right, while looking through the fingers, into the distance, and not on them. Let glance glides without lingering on one thing. If you do everything right, your hands will “float” past you: it should seem like they are moving.
Make alternately three turns with eyes open and three with closed (even closed eyes should “not linger” on anything. Do the exercise 20-30 times, breathe freely, do not strain.
If you cannot achieve the effect of the movement, try this. Pull out your index finger. He must “look” up. And your nose should touch him. Close your eyes and turn your head left and right so that the nose, passing by the finger, touches it. Without ceasing to turn your head, open your eyes (just do not focus your attention on the finger, look into the distance!). You will surely see that the finger is “moving.”
For those who find it difficult to open their eyes in the morning, this complex will be a real salvation. And if during the day you can do palming several times (at lunchtime – longer, every 1-2 hours at least 10-15 seconds) and “write” something with your nose (at lunchtime and on the way from work), you will feel that over time your eyes will no longer tire as they used to. You can do some exercises at night. Especially if, before going to bed, you watch TV, sit at the computer or read.
So back again in the morning.
- Stretch well, roll a few times from side to side.Do not hold your breath.On the contrary, breathe deeply and calmly.
- Wide open eyes and mouth several times.
- Close your eyes tightly (6 times), make 12 light blinks.
- Make aexercise ” letternose . “
- Do an eyebrow drill (see description below).
- Make afingersturns .
- Make a
Palming should take about 5 minutes. The rest of the complex should take the same amount of time (6 previous exercises).
In the morning, many of us want to say, like Gogol Viyu : “Lift me forever!”. And over time, they become harder and harder. Exercise for eyebrows not only help your eyes get rid of the pressure of this weight, but also help you look younger.
Raise the eyebrows as high as possible, while watching the sensation that will appear in the upper part of the ears. Your task is to reproduce this feeling over time without raising your eyebrows. Of course, not everyone can do this exercise right away. It is possible that for the first time having raised eyebrows, you will not catch any special sensations. Do not hurry, listen to yourself, and you will succeed.
The main complex of yoga for the eyes
This yoga complex recommends keeping eyesight in good condition. According to the yogis themselves, if you do it daily in the morning and in the evening, beginning with your youth, you can maintain good vision until old age and not use glasses.
Before performing the complex, sit in a comfortable position (well, if you can sit on your heels on a gymnastic mat, but you can also sit on a chair). Straighten the spine. Try to relax all the muscles (including the muscles of the face), except those that support a seated posture. Look straight ahead into the distance, if there is a window – look there, if not – look at the wall. Try to focus on the eyes, but without undue stress.