Perifériás látás

Peripheral vision (also known as side vision) is the part of the visual field that is beyond the direct focus of your gaze. This means that peripheral vision allows you to perceive objects and movement around you that are not directly in front of you.

Human vision is divided into central vision and peripheral vision:

1. Central vision: Central vision is responsible for seeing objects and details in the center of your field of vision. It is used for reading, focusing on fine details, and performing tasks that require high precision and resolution.
2. Peripheral vision: Peripheral vision allows you to see a wide area of the environment outside of the central focus. It is not as sharp and detailed as central vision, but it plays an important role in detecting motion, providing orientation and safety, and perceiving a wide peripheral environment.

Peripheral vision allows us to see moving objects, hazards and changes in the environment without having to turn our eyes or head in one direction or another. It is especially important in situations where we need to assess our surroundings, such as when driving, playing sports or traveling.

Deterioration of peripheral vision may be associated with various diseases or conditions such as glaucoma, diabetic retinopathy, or neuro-optic disorders and may require the intervention of an ophthalmologist for diagnosis and treatment.

Functions of peripheral vision

Peripheral vision, also known as side or surround vision, performs several important functions in our lives and provides a vast field of vision beyond the central visual field. Here are some of the major functions of peripheral vision:

1. Motion Detection: Peripheral vision plays a key role in detecting the movement of objects and events in the environment. This allows us to react to potential hazards such as cars on the road or rapidly approaching dangerous objects.
2. Orientation in space: Peripheral vision helps us orient ourselves in space and maintain stability. For example, when we walk or run, peripheral vision allows us to see the surface and objects around our feet, which helps us avoid falls.
3. Contour recognition: Our eyes are able to recognize the contours of objects and shapes even in our peripheral vision. This can be useful, for example, when looking for something in a room without having to turn your head.
4. Analyzing our surroundings: Peripheral vision helps us perceive our surroundings as a whole, even when we are not looking directly at an object. This is especially important in situations where we need to assess the overall environment, such as when driving a car.
5. Maintaining focus: Peripheral vision allows us to remain focused on central objects or tasks without being distracted by surrounding objects. This is especially important when performing tasks that require close attention.
6. Recognizing emotions and gestures: Peripheral vision can also play a role in recognizing emotions on faces and perceiving the gestures or movements of others.

Examination of peripheral vision

Performed in an ophthalmology practice to assess the breadth and quality of your visual field beyond the central area. These examinations can help detect the presence of diseases or conditions that may affect your peripheral vision, such as glaucoma, diabetic retinopathy, tumors, or other pathologies.

Here are a few methods of examining peripheral vision:

1. Visual field (perimetry): Your visual field can be assessed using special devices called perimeters. During this study, you will be asked to fix your gaze on a fixation point in the center of the screen, and then you will need to react to the appearance of objects or light flashes on the periphery of the screen. The study will record how far from the center you see the objects.
2. Background Camera: Sometimes during a general eye exam, an ophthalmologist may notice changes in peripheral vision by examining the back of the eye with special equipment.
3. Electrophysiologic studies: Electrophysiologic techniques such as electroretinogram (ERG) and electrooculogram (EOG) can be used to study retinal functionality and peripheral vision.
4. Computer-based tests: Some ophthalmic practices use computer programs and tests that assess peripheral vision using a monitor.

Normal peripheral vision in humans covers a wide angle, about 100-120 degrees horizontally and about 60-70 degrees vertically. This means that under normal conditions a person's visual field includes the environment around him, and he is able to perceive objects and motion around him without the need to actively turn his head or eyes.

It is important to note that normal peripheral vision can vary from person to person and from age to age. However, it usually remains within the above limits.

Development of peripheral vision

Depends on several factors, and it can change over the course of a person's life.

Here are a few key aspects related to the development of peripheral vision:

1. Physical development of the eye: The development of peripheral vision begins with the physical development of the eye and its structures. This includes the shape and size of the eyeball, characteristics of the cornea, lens and retina. The visual receptors (cones and rods) on the retina play an important role in perceiving light and providing peripheral vision.
2. Training and Experience: Our experiences and training can affect our peripheral vision. For example, people who participate in sports, exercise, or vigorous activities may develop better peripheral vision because they often orient themselves in space and react to movement outside their direct field of vision.
3. Age: As people age, many people notice changes in their peripheral vision. This may be due to natural changes in the structure of the eye, decreased sensitivity of the retina, or age-related eye diseases.
4. Diseases and Conditions: Certain diseases and medical conditions, such as glaucoma or diabetic retinopathy, may affect and impair peripheral vision.

Exercises to improve peripheral vision

Peripheral vision can be improved with special exercises and training. These exercises will help to strengthen and develop peripheral vision and improve eye coordination. Keep in mind that visible improvement may take time and regular practice. Here are some exercises to improve peripheral vision:

1. Ball exercise:

   • Take a ball (preferably bright and colored) and sit on a chair or bench.
   • Hold the ball in front of you at eye level.
   • Slowly start moving the ball in different directions while keeping your eyes on the ball.
   • Gradually increase the speed of the ball and the variety of directions.
   • Continue the exercise for 2-3 minutes, then pause and repeat several times.

2. An exercise in shifting attention:

   • Sit in a comfortable position and focus on the object in front of you.
   • Quickly shift your gaze from this object to other objects in your peripheral visual field.
   • Try to notice the details and colors around you without focusing on them directly.
   • You can use a bar with letters or numbers, moving your gaze from one letter to the next in different directions.

3. An exercise in observing moving objects:

   • Sit by a window or in a place with active traffic and people.
   • Observe different moving objects in your peripheral visual field without turning your head.
   • Try to notice the different speeds and directions of objects.

4. Coordination exercises:

   • Many exercises to improve coordination between the eyes can also help improve peripheral vision. Examples of such exercises include practicing focusing on two different objects, closing one eye and looking at objects with the other, and practicing using transparent panels and other aids.

Peripheral vision impairment

Also known as "tunnel vision" or hemianopsia, is a condition in which vision at the edges of the visual field becomes limited or absent. This condition can be caused by a variety of reasons, and its diagnosis and treatment depends on the underlying condition. Here are some of the possible causes of peripheral vision impairment:

1. Glaucoma: Glaucoma is a group of eye diseases that result in increased intraocular pressure and damage to the optic nerve. One of the symptoms may be impaired peripheral vision.
2. Migraine: Some people may experience temporary impairment of peripheral vision during a migraine (aura).
3. Vascular disease: Vascular disease, such as a stroke or aneurysm, can affect the blood supply to the eye and cause impaired peripheral vision.
4. Brain tumors: Tumors located in the brain can put pressure on the optic nerve or other structures and cause changes in the visual field.
5. Retinitis pigmentosa: This is a group of genetic diseases that can lead to loss of peripheral vision.
6. Other Causes: Peripheral vision can also be impaired due to trauma, infections, inflammation, or other eye diseases.

Types of peripheral vision disorders

Peripheral vision disorders can be caused by a variety of medical conditions and diseases, and they can manifest in different degrees and forms. Some of the most common types of peripheral vision disorders are listed below:

1. Narrowing of the visual field (tunnel vision): This condition is characterized by a reduction in the visual field, in which a person sees only the central region of the visual field and hardly notices objects and movement in the periphery. It can be caused, for example, by glaucoma or neuro-optical disorders.
2. Hemianopsia: Means loss of vision in half of the visual field. There can be different types of hemianopsia, such as binasal (loss of the outer half of the visual field) or binasal (loss of the inner half of the visual field).
3. Blind spot (scotoma): This is an area of the visual field where vision is absent. It can be caused by a variety of factors, including tumors, retinal or nerve damage.
4. Hemiopsia: Refers to loss of vision in one half of the upper or lower part of the visual field. This condition can be caused by a variety of pathologies, including vascular disease and others.
5. Structural distortions: Sometimes peripheral vision can be distorted or distorted due to changes in the structure of the retina or the eye fundus. This may manifest itself, for example, as curved lines or deformed objects in the periphery of the visual field.
6. Night blindness: Associated with a person having difficulty seeing in low light conditions, especially at night. It may be caused by a deficiency of rhodopsin (the photoreceptor responsible for seeing in low light) or other conditions.

Loss of peripheral vision

Can result from a variety of medical conditions and diseases. This problem can manifest itself in a variety of ways, including decreased visual field width, blurred or distorted peripheral vision. Here are a few of the most common causes of peripheral vision loss:

1. Glaucoma: It is a chronic eye disease characterized by increased intraocular pressure and damage to the optic nerve. Glaucoma often results in loss of peripheral vision, and symptoms may develop slowly and imperceptibly.
2. Diabetic retinopathy: In diabetic patients, retinal blood vessels may be damaged, which can cause loss of peripheral vision.
3. Tumors and cysts: Tumors or cysts that develop in the eye cavity or adjacent structures can put pressure on the retina and cause loss of peripheral vision.
4. Macular Degeneration: Chronic disease of the macula (central area of the retina) can affect peripheral vision as a result of changes in the retina.
5. Aging: As we age, some people may experience a natural decline in peripheral vision.
6. Trauma and Infection: Trauma to the eye, infection or inflammation can also affect visual function, including peripheral vision.