Vision - one of the most important processes in the perception of the surrounding world.
In the visual system involves many functions.
One of these is the peripheral vision.
General information about the peripheral vision
Peripheral vision - is one of the componentsparts of the visual apparatus, which is responsible for the border of the field of view when projecting them on a spherical surface. The field of view is a kind of space that is perceived by the eye in a stationary condition. Visual field - is one of the functions of the peripheral retina departments, which determines whether a person is easy to navigate in space.
The main indicator of the productivity of peripheral vision is the human angle of view.
As for the field of view indicator, it hasspecific values that define the boundaries of the retina. Thus, for example, only 90 responds to white eye color? - Retina outward, 70? - Upwards outwards, 55? - Upwards into the 55? - Inside, 50? - Down inside, 65? - Down 90? - Down outwards.
"Blind Spot" - this is one of thosephysiological cattle which is in the temporal field of vision. Along with physiological scotomas exist angioscotoma (ribbon-like "loss" resulting from the increased vascular retikalnyh closing photoreceptor cells), but they are only slightly degrade the peripheral vision and is considered the norm.
Those areas that fall outside of the field of vision, called "scotoma".
Scotoma are divided into three types:
Positive scotoma can be recognizedindependently in the form of black spots in the visual field. They are the first sign of damage to the retina. Negative scotoma can identify only by survey. The cause of such cattle - pathways damage.
Scintillating scotoma appear spontaneously. They mainly occur due to spasms of cerebral vessels. If his eyes closed, one sees colorful zigzag lines outside the peripheral vision, experts recommend to immediately start taking antispasmodic drugs.
The list of issues that contribute to the deterioration of peripheral vision
The deterioration of peripheral vision contribute to the following eye problems:
1. The initial stages of swelling and inflammation. In these diseases may be lost? part of the field of view.
2. Various retinal pathologies. Depending on this vision can deteriorate in several areas. For example, glaucoma contributes to narrowing the field of view of the nose.
3. The affected nerve and retinal dystrophy. This problem leads to a narrowing of the field of vision on all sides by 5-10 ?, this is known as concentric contraction of the visual field. In this disease, a person can see and read, but completely loses the ability to orient himself in space.
In any case, when an eventhe slightest hint of the deterioration of peripheral vision should seek the advice of professionals. After the necessary examinations, they will put the correct diagnosis and help you to save vision.