They say that the eyes are the windows to the soul, that just by looking at a person we can get to know them completely. By staring we become aware of the lies, truths and reactions we cause in others.
Seeing every detail of the world and discovering the beauty in the colors and shapes of everyday life. But have you ever wondered: How exactly does our ocular system work?
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After all, it is made up of many parts that we can see and others that we can’t because they are inside our brain, connected by thousands of nerve endings that work to make our eyes function. Are you curious to find out more?
In this article we will talk about the parts of the eye and all of its characteristics so you can appreciate all the inner workings of the eye. so you can appreciate all the inner workings that make it possible for us to see.
How does the human eye work?
Essentially, the human eye is a photoreceptor organ, that is, it is able to detect light and its nuances, to give shape and meaning to objects in the world. This occurs thanks to the transformation of light energy into electrical impulses, which are sent through the optic nerves to the nervous center of vision, located in the occipital part of the brain.
There are 6 ocular muscles that are in charge of carrying out eye movements (up, down and sideways) and to focus convergently. That is, both visual fields (left and right) can be oriented towards the same object being viewed. This is thanks to the simultaneous functioning of both.
Anatomy of the human eye
The human eye is a sphere of 12 millimeters in radius, with a kind of dome in its front part, which has a radius of 8 millimeters. It is also extremely sensitive to external agents that penetrate its interior, including the tiniest ones such as dust or water droplets, because it is an innervated organ, which means that it has many nerve fibers.
But it also has an anatomy that is it has an anatomy that can be divided into three major structures, depending on its layers.depending on its layers. Which have different parts that are responsible for a specific function. Find out what they are.
1. Outer layer of the eye
It is the somewhat “invisible” layer that supports and protects the entire ocular organ.It is located in the front part of the eye, which is exposed to external factors and agents of the environment.
This refers specifically to the convex dome or spherical cap that covers the eye as such. It is characterized by being a transparent tissue without blood vessels, although it is affected by the innervation of the eye that connects it to the nervous system. Its main function is to refract and send light to the back of the eye, that is, to the retina.
This part is visible to us, we know it as the white background of our eyes, where small blood vessels are visible in addition to the iris. It is also known as the ocular skeleton, as it is what helps the eye to keep its shape.
Its structure is opaque and fibrous in texture and contains the external muscles that allow eye movements.
It is a membrane that surrounds the sclera and its function is the production of tears and mucus. These serve as a form of lubrication and natural disinfection of the eye.
2. Middle layer of the eye
It is the visible layerIt represents the focal point of the entire ocular organ, including its color.
They contain the blood vessels and connective tissue of the eyeball, which oxygenate and nourish the eyeball so that it can function properly. They also contain a type of pigment that helps reduce excess light, thus preventing blurred vision.
2.2. Crystalline lens
It is the natural lens of the eye and its main function is to focus objects perceived from different distances, helping the retina to shape the image we are seeing.
It is located behind the iris and is composed of a biconvex, elastic and transparent lens, which has the ability to change shape to adapt its focus. This ability is also known as “accommodation”.
We know this structure as the one that has the color of our eyes (which is given according to our melanin concentration). But it is also responsible for protecting and regulating the amount of light that enters our eyes and depending on the level of illumination present around us, it has the ability to contract or dilate, processes called miosis and mydriasis respectively. It also serves as a separation between the anterior and posterior layer of the eye.
We can appreciate it as the small black hole in the center of the iris, since it is bordered by the iris. It is a hollow cavity, so it is possible to observe the inside of the eye itself. It works together with the pupil in the regulation of the amount of incoming light, so it also has the capacity of mydriasis and miosis depending on the ambient light.
2.5. Ciliary body
It is responsible for several functions that influence the structures of the middle layer. For example: it is in charge of joining the iris with the choroids, it is the one that produces the acoustical humor of the eyeball and it is the one that provides the process of accommodation of the crystalline lens.
3. Inner layer of the eye
Also known as the posterior cavity, is what can be found at the end of the pathway and is in charge of visual functions..
3.1. Aqueous humor
As its name suggests, it is a clear aqueous fluid rich in vitamin C, glucose, lactic acid and proteins. It is present in both the internal cavity and the anterior cavity. Its main function is to oxygenate and nourish the cornea and the crystalline lens.
It is necessary to have a delicate balance between the production and outflow of aqueous humor because an excess of it inside the cornea can cause high intraocular pressure and lead to diseases such as glaucoma.
The vitreous humour, on the other hand, is actually a transparent tissue with a gel-like texture that protects the eye from possible impacts. It occupies two thirds of the ocular structure as it is found throughout the interior of the eye.
It is located in the deepest part of the eyeball and is responsible for the function of the visual capacity, including its sharpness and the discrimination of object details. Therefore, both its structure and its role is complex. It is a photosynthetic membrane, so it is the place where light is transformed into energy to be carried to the nervous system through the optic nerves.
It has cells that are sensitive to light (cones and rods) known as photoreceptors. As a curiosity is that there are only 3 cones and are responsible for color perception, but thousands and thousands of rods which are responsible for producing the shades of black and white and adapt our night vision, which is why they are more sensitive.
Care for our eyes
It is important that we have a routine of care for our eyes, so that they can maintain their health.It is important that we have a routine of care for our eyes so that they can maintain their health and optimal functions for a long time. It is normal that with time, the visual capacity wears out, but if we subject our eyes to certain activities we can accelerate this degeneration earlier than normal.
1. Exposure to light
Excessive exposure to light is one of the most common causes of eye diseases, eye discomfort and wear and tear on the quality of the eye. Since the structures are overworking in front of a luminosity that is difficult to regulate for a long time.
Therefore, it is necessary to avoid spending too much time in front of your computer or any electronic device, not to look directly into the sunlight, to go outside during a very sunny day without sunglasses and to reduce the intensity of artificial lights in a small place.
2. Reduce reflection
The reflection of light on the natural lens or on the glasses also causes eye discomfort such as headaches, sensation of heaviness or eye swelling, irritation and dryness. If not treated in time, these can lead to major complications over time, such as blurred vision or loss of focus.
So be sure to reduce the brightness of your electronic devices as much as possible so that they adapt to your field of vision and the ambient brightness, opt for night mode if you read at night and place blue light filters on them during the day. Also be sure to ask for anti-reflection on your glasses when you go to your optician to avoid light reflection on the lenses.
3. Straining your eyes
This occurs when we try to focus the eye as much as possible to a point that causes discomfort. For example, when reading small letters, reading on a bright screen or, on the contrary, performing activities without the right amount of light. So always try to make the most of natural daylight and don’t keep working in the dark.
4. Take care of your sugar
Sugar levels are closely related to the health and functionality of the eye, remember that the aqueous fluid contains glucose and having diabetes or insulin problems can affect visual quality over time. Inciding in the appearance of cataracts.
5. Nourish yourself
It is important to consume nutrients that benefit eye health, such as foods rich in vitamins C and A, minerals that help protect them from UV rays and proteins that strengthen the immune system to prevent diseases and eye discomfort. For example: green, yellow and orange fruits, vegetables rich in beta-carotene, dairy products, eggs and white meats.
6. Have a regular eye checkup
It is always important to visit an ophthalmologist at least once a year to check the health of our eyes.. In this way we can be forewarned of natural disasters, recommended treatments or tips to reduce their occurrence.
Similarly, if you have glasses indicated by a specialist, you should have a regular checkup to evaluate the quality of the lenses and the evolution of your improvement.