The pupil is responsible for regulating the rays of light entering the retina. Therefore, with different lighting, the diameter of the pupil also changes. But not only the rays of light can affect its size, there are many internal and external factors contributing to such changes. Internal refers to the reaction to various processes in the body. And vernal ones include irritants that occur in the human environment.
In medical practice, dilated or narrowed pupils represent a whole storehouse of information, as they can become an indicator of serious diseases. That is why, during diagnosis, this symptom is given special attention.
Two major muscles are involved in the process of resizing the pupil. Radial is responsible for the expansion of the diameter, and circular creates a narrowing of the pupil. These muscles are directly related to the activity of the nervous system, therefore, according to the state of the eyes, one can judge the psychological health of a person. It is known that in the presence of stressful situations or severe depression, the pupils are narrowed and there is distraction in the gaze.
Do not be surprised that over the years the pupil becomes smaller, as this is a normal process. For all organs, tissues and muscles, aging is characteristic, that is, a decrease in the activity of metabolic, mental and other processes. In addition, in bright light or on a sunny day, you can see that the pupils are narrowed. It was already mentioned above that this is a normal reaction to excess light, so the body protects the retina. But twilight or dim light leads to a reverse reaction. An interesting fact is that with poor lighting, brain activity and the productivity of the work performed are reduced.
By the diameter of the pupil, you can determine what vision problems a person suffers from. So with hyperopia, the pupils are narrowed, and with myopia, respectively, vice versa. With the rapid deterioration in the clarity of vision, you can notice how greatly its diameter increases.
Everyone knows that a drug addict can be identified by an oversized pupil. But not everyone understands that the use of alcohol and tobacco products is also reflected in the eyes, only people with such bad habits have narrow pupils.
There is a whole list of diseases that can be recognized by eye condition. For example, one of the symptoms of such a serious disease as meningitis is a decrease in the pupil, but only at an early stage of development, with the progression of the disease, its diameter changes and expands. Also, with high intracranial pressure, the pupils are narrowed. If only one side of it changes, then it is worth talking about pathology in a certain hemisphere of the brain.
In medicine, there is such a thing as a clinical cramp of the pupil. It involves continuous expansion and contraction of the pupil. As a rule, this symptom refers to tuberculosis, multiple sclerosis , traumatic brain injuries of special severity, epilepsy. Often there is a change in the reaction to light, that is, the pupils are narrowed in dim lighting.
Morphine is known to act like any narcotic substance, causing pupil dilation. However, with an overdose, intoxication of the body occurs, that is, poisoning with this substance, and the diameter of the pupil is significantly reduced.
If a person leads a healthy lifestyle and external factors do not directly affect him, and the pupils are still narrow, this may be a signal about the need for a thorough examination. The specialist in this case can detect a brain tumor or rupture of cerebral vessels, followed by hemorrhage.
Thus, there are situations in which a change in pupil size should alert. If in addition to this symptom there is an ailment, then the trip to the doctor should not be postponed.