Eye Rehabilitation II.

Eye Rehabilitation II.

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What is the effect of the red eye and what does it tell the doctor? This article reveals many other things.

The nerve

The innermost layer of the eyeball is the retina, which protrudes from the eyelid to a thin spot. Where it is thicker, it is only 0.5 mm. In the retina are located nerve cells capable of sensing light.
If you are making a photo of someone with a flash, you will usually have a "red eye" in the image. This is not good for the image, but it goes far beyond the model. The "red back light", as the medical language calls it, is caused by the glare inside the eye. The healthy retina is perfectly shaped, but the hairline below it is cut by the hairline. The red color of this dense structure is seen to shine in the pupil area when the "corneas, lenses and vitreous" of our model are clear.
A good red back light means that the light shines completely down to the retina, the person being depicted is actually looking good. It is also worthwhile to make a "bad" photo of a baby doll. The red eye does not mean that everything is okay, but if one of the eyes has not seen a red back light, it is enough reason to visit the child's eye urgently.

Infants' eyepieces are still fully elastic.

Taps and racks

The human eye has two different sensory cells, rods and pins. Cocks are called nerve cells specialized in fertilization, with around 6 million in the total retina. Three different groups of them represent red, blue and green light. The pins need more light to function, but they are a much richer image than the pins.
The distribution of the biphasic sensory cells in the nerve cortex is not uniform. The place of arousal is a distinguished area of ​​the retina. It was named after a yellow cat color, called "macula latin" (Latin for macula lutea). In order to see an "immaculate" image of our environment, the yellow spot must work perfectly. The area of ​​the macula lutea is exclusively pins, much more densely assembled than the rest of the nerve cortex. For the finest visual tasks - writing, reading - this entire 1.5mm diameter area requires the health of a whole.
At the edges of the yellow spot, the density of the pins is reduced, and then the seats are completely lined up. There are 120 million of them in the eye, they are only found in black and white, but they are extremely sensitive to light and work well in the dark. With just a faint light - say, in a starlit night - we have all experienced the fact that we look at things quite a bit. So we do not examine them with pins, in the dark "helpless" yellow spot, but with scalpels located in other areas of the nerve end.

Electrical signal

Sensitive cells contain different dye pigments, which are capable of absorbing light at specific wavelengths and decomposing. In the dark, there are unidirectional ionic fluxes on the two sides of the limiting membrane of the sensitive cells, which results in an increasing voltage. When the light arrives, this charge flow is interrupted by the chemical reaction of the paint decomposition. The firefighter "kicks" the tension.
There is evidence that the labels, which are designed to differentiate between darkness and light, are so sensitive that they can indicate the entry of only a single photon - a packet of light energy. The pins need at least 5-7 times as much light to generate a signal and perform color-differentiating roles.
In order for the pins and trays to give birth to new lighters, they need to regenerate, which takes a little time. During this time, they are required to repair the degraded toner and to restore the tension along the cell wall.
Sensory cell signaling is an extremely nutrient and oxygen consuming process. Sensory cells die within 6 urns, if they do not get food, disturbance of the nerve oxygen supply causes just a couple of hours of blindness. The retinopathic arteries also start out from the nerve head and cover the buttocks. Blocking the central retinal power of the retina creates an "infarction" of the eye.

The retina pops

The light reaches 300,000 km / s first through the cornea, the lens and then the retina through the vitreous - the speed of light, even if it is small, but varies in size.
The two most important lighting elements are the cornea and the lens. Luminous abilities are determined by the radius of curvature and the refractive index of their material. For the sake of simplicity, we can model the luminous power of the photocells with a single appropriate lens.
The luminous efficacy of the eye is given by diopter, which is the reciprocal of the lens focal length. Replacing the illuminating elements of the human eye, the lens would have a focal length of 15 mm. This means that at such a distance the rays of light meet at one point before the lens and before the retina. Thus, the refractive power of the eye is 66.6 diopters (1 m / 0.015 m = 66.6). From this, the horn capacity of the cornea is approx. 42 dioptres, lens approx. 24 dioptres jut. As the light beams intersect before the retina, the image on the retina is reduced. Since the image to be processed is always retinal and is of a sufficient size, the eye must adapt. This is called accomodation, which can be done by changing the shape of the lens. (In the near future, when the pupils are working, the pupils are working, drooping, and the two eyelids are turning over each other, and the inside is tickling.
The eyes are made of the fact that objects of infinite distance - in practice, more than 5 meters - fall on the retina without adaptation. Closer to the subject, the resized image would be the retina, if not changed with this lens embossing.
Remotely, when the radiation body adheres to the lens attaching fibers, it relaxes, flattening the inner surface of the eye. The lenses hanging on the lens thus stretch, stretch the lens case, and flatten the lens inside. For a close look, you have to do some work, the muscular ring of the radius is tightened, the lens-hanging fibers are no longer stretched, the lens is shrinking, it is more convex.
The young man's eyepieces are still very flexible, so he doesn't have to worry about deformation. Without adaptation, the farthest line of sight (distal point) in the young eye is virtually infinite, and the ability to adapt is fully visible (center) about 10 cm in front of the eye. The difference between the two is also given by diopter. These values ​​can be up to 10-15 dioptres in infancy.

The retina is part of the brain

Information from the pins and trays passes through the nerve cells located in the retina in multiple layers. In fact, the retina does not contain all receptor cells. At least the other half of the nervous system cells work, and they function as an elementary processor, a regulating unit, and more and more, the transformation of some information from the world begins in the retina.
By virtue of its development, structure and function, the retina is considered to be a part of the brain. Finally, the long strands of nerve cells run into nerve fibers and then run around the corpus luteum to a diameter of 1.5 mm. There are no filamentous cells in the optic nerve, so the nerve is "blind" in this area. That's why this area is called the blind spot. Half of the fibers of the optic nerve intersect at the base of the brain. Fibers that cross the nasal passages of the retina only intersect. Information from the nasal areas of the retina of the left eye to the right cerebellum, from the same areas of the retina of the right eye to the left cerebellum is processed. Nerve fibers from the retina areas of Halabnet do not cross. This arrangement helps us to determine at what stage of the atrium, in certain cases of lesions of the optic nerve, or in the case of a brain tumor affecting the larynx alone.
The cool nerve drives information to the brain at a speed of 100 m / s. Interruption, destruction of the optic nerve (eg, pituitary gland) causes immediate and unfortunately incurable blindness. Because of its complex microscopic organization, it is not possible to "patch" it up again with today's neurosurgical methods.
Because of the intersection of the optic nerve, the primary visual cortex found in the occipital lobe receives information from each person in front of the brain. Here we become aware of what we have seen, and its operation is required for visual memory. Important granules from the visual cortex lead further to the pineal gland. By being aware of the changes in the time of day, our body develops the circadian rhythm of our bodies and minds (24 hrs).
Eye Rehabilitation and Functioning I.


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