The human autonomic nervous system has a direct impact on the work of many internal organs and systems. Thanks to it, breathing, blood circulation, movement and other functions of the human body are carried out. Interestingly, despite its significant influence, the autonomic nervous system is very "hidden", that is, no one can clearly feel changes in it. But this does not mean that it is not necessary to pay due attention to the role of the ANS in the human body.
The human nervous system: its divisions
The main task of the human NS is to create an apparatus that would connect all organs and systems of the human body together. Thanks to this, it could exist and function. The basis of the human nervous system is a kind of structure called a neuron (they create contact with each other using nerve impulses). It is important to know that the anatomy of the human NS is a combination of two departments: the animal (somatic) and autonomic (vegetative) nervous systems.
The first was created mainly to ensure that the human body can contact the external environment. Therefore, this system has its second name - animal (i.e., animal), due to the performance of the functions that are inherent in them. The significance of the autonomic nervous system for humans is no less important, but the essence of its work is completely different - control over those functions that are responsible for respiration, digestion and other roles that are predominantly inherent in plants (hence the second name of the system - autonomous).
What is the human autonomic nervous system?
VNS carries out its activities with the help of neurons (a set of nerve cells and their processes). They, in turn, work by sending certain signals to various organs, systems and glands from the spinal cord and brain. It is interesting that the neurons of the vegetative part of the human nervous system are responsible for the work of the heart (its contraction), the functioning of the gastrointestinal tract (intestinal peristalsis), and the activity of the salivary glands. Actually, this is why they say that the autonomic nervous system organizes the work of organs and systems unconsciously, since initially these functions were inherent in plants, and then already in animals and humans. The neurons that form the basis of the ANS are capable of creating some clusters located in the brain and spinal cord. They were given the names "vegetative nuclei". Also, near the organs and the spine, the vegetative section of the NS is able to form nerve nodes. So, the vegetative nuclei are the central part of the animal system, and the nerve nodes areperipheral. In fact, the ANS is divided into two parts: parasympathetic and sympathetic.
What role does the ANS play in the human body?
Often people cannot answer a simple question: "The autonomic nervous system regulates the work of what: muscles, organs or systems?"
In fact, it is, in fact, a kind of “response” of the human body to irritations from the outside and from the inside. It is important to understand that the autonomic nervous system works in your body every second, only its activity is invisible. For example, regulating the normal internal state of a person (blood circulation, respiration, excretion, hormone levels, etc.) is the main role of the autonomic nervous system. In addition, it is able to have the most direct impact on other components of the human body, say, muscles (cardiac, skeletal), various sensory organs (for example, dilation or contraction of the pupil), glands of the endocrine system, and much more. The autonomic nervous system regulates the work of the human body through various influences on its organs, which can be conditionally represented by three types:
- control of metabolism in the cells of various organs, the so-called trophic control;
- an indispensable effect on the functions of organs, for example, on the functioning of the heart muscle - functional control;
- influence on organs by increasing or decreasing their blood flow - vasomotor control.
Composition of human ANS
It is important to note the main thing: VNSdivided into two components: parasympathetic and sympathetic. The last of them is usually associated with such processes as, for example, wrestling, running, i.e., strengthening the functions of various organs.
In this case, the following processes are observed: an increase in contractions of the heart muscle (and, as a result, an increase in blood pressure above normal), increased sweat secretion, enlarged pupils, weak work of intestinal peristalsis. The parasympathetic nervous system works in a completely different way, that is, in the opposite way. It is characterized by such actions in the human body, in which it rests and assimilates everything. When it begins to activate the mechanism of its work, the following processes are observed: pupil constriction, reduced sweating, the heart muscle works more weakly (i.e., the number of its contractions decreases), intestinal motility is activated, blood pressure decreases. The functions of the ANS are reduced to the work of its above-studied departments. Their interconnected work allows you to maintain the human body in balance. In simpler terms, these components of the ANS should exist in a complex, constantly complementing each other. This system works only because the parasympathetic and sympathetic nervous systems are able to release neurotransmitters, which connect organs and systems using nerve signals.
Control and verification of the autonomic nervous system - what is it?
Functions of the autonomicnervous system are under the continuous control of several main centers:
- Spinal cord. The sympathetic nervous system (SNS) creates elements that are in close proximity to the spinal cord stem, and its external components are represented by the parasympathetic division of the ANS.
- Brain. It has the most direct effect on the functioning of the parasympathetic and sympathetic nervous systems, regulating the balance throughout the human body.
- Stem brain. This is a kind of connection that exists between the brain and spinal cord. It is able to control the functions of the ANS, namely its parasympathetic division (blood pressure, respiration, heart rate, and more).
- The hypothalamus is part of the diencephalon. It affects sweating, digestion, heart rate, etc.
- The limbic system (in fact, these are human emotions). Located under the cerebral cortex. It affects the work of both departments of the ANS.
Given the above, the role of the autonomic nervous system is immediately noticeable, because its activity is controlled by such important components of the human body.
Functions performed by the ANC
They arose thousands of years ago, when people learned to survive in the most difficult conditions. The functions of the human autonomic nervous system are directly related to the work of its two main divisions. So, the parasympathetic system is able to normalize the work of the human body after the stress (activation of the sympathetic division of the ANS). So the emotional statebalanced. Of course, this part of the ANS is also responsible for other important roles, such as sleep and rest, digestion and reproduction. All this is carried out by acetylcholine (a substance that transmits nerve impulses from one nerve fiber to another).
The work of the sympathetic department of the ANS is aimed at activating all the vital processes of the human body: blood flow to many organs and systems increases, the heart rate increases, sweating increases and much more. It is these processes that help a person survive stressful situations. Therefore, we can conclude that the autonomic nervous system regulates the work of the human body as a whole, in one way or another affecting it.
Sympathetic Nervous System (SNS)
This part of the human ANS is associated with the struggle or response of the body to internal and external stimuli. Its functions are as follows:
- inhibits the work of the intestine (its peristalsis), due to a decrease in blood flow to it;
- increased sweating;
- when a person does not have enough air, his ANS with the help of appropriate nerve impulses expands the bronchioles;
- due to the narrowing of blood vessels, an increase in blood pressure;
- normalizes blood glucose levels by lowering it in the liver.
It is also known that the autonomic nervous system regulates the work of skeletal muscles - this is directly involved in its sympathetic department.
For example, when your body is under stress in the form of fever, the sympathetic division of the ANS immediately works as follows: it transmits the appropriate signals to the brain, and it, in turn, increases sweating or expands the skin with the help of nerve impulses. pores. Thus, the temperature is greatly reduced.
Parasympathetic nervous system (PNS)
This component of the ANS is aimed at creating in the human body a state of rest, calmness, assimilation of all vital processes. His work boils down directly to this:
- enhances the work of the entire gastrointestinal tract, increasing blood flow to it;
- acts directly on the salivary glands, stimulating the production of saliva, thereby accelerating intestinal motility;
- reduces pupil size;
- exercises the strictest control over the work of the heart and all its departments;
- reduces the size of bronchioles when blood oxygen levels become normal.
It is very important to know that the autonomic nervous system regulates the work of the muscles of various organs - this issue is also de alt with by its parasympathetic department. For example, uterine contraction during arousal or in the postpartum period is associated precisely with the work of this system. A man's erection is subject only to her influence. After all, with the help of nerve impulses, blood enters the genitals of a man, to which the muscles of the penis react.
How stressfuldoes the situation affect ANS?
I would like to say right away that it is stress that can cause the ANS to malfunction. The functions of the autonomic nervous system can be completely paralyzed when such a situation occurs. For example, there was a threat to a person's life (a huge stone falls on him, or a wild animal suddenly appeared in front of him). Someone immediately runs away, while the other will simply freeze in place without the ability to move from the dead center. It does not depend on the person himself, this is how his ANS reacted at the unconscious level. And all this because of the nerve endings located in the brain, the medulla oblongata, the limbic system (responsible for emotions). After all, it has already become clear that the autonomic nervous system regulates the work of many systems and organs: digestion, the cardiovascular apparatus, reproduction, the activity of the lungs and urinary tract. Therefore, in the human body there are many centers that can respond to stress due to the work of the ANS. But do not worry too much, since most of our lives we do not experience strong shocks, so the occurrence of such conditions for a person is rare.
Deviations in human he alth caused by improper functioning of the ANS
Of course, from the above, it became clear that the autonomic nervous system regulates the work of many systems and organs in the human body. Therefore, any functional violations in its work can significantly disrupt this workflow.
By the way, the causes of such disorders can beeither heredity or diseases acquired in the course of life. Often the work of the human ANS is “invisible” in nature, but problems in this activity are already noticeable on the basis of the following symptoms:
- nervous system: the body's inability to lower body temperature without help;
- GI: Vomiting, constipation or diarrhea, inability to swallow food, urinary incontinence and more;
- skin problems (itching, redness, peeling), brittle nails and hair, increased or decreased sweating;
- vision: fuzzy picture, no tears, difficulty focusing;
- respiratory system: improper response to low or high oxygen levels in the blood;
- heart and vascular system: fainting, palpitations, shortness of breath, dizziness, tinnitus;
- urinary system: any problems in this area (incontinence, frequency of urination);
- reproductive system: inability to achieve orgasm, premature erection.
People suffering from an ANS disorder (autonomic neuropathy) often cannot control its development. It often happens that progressive autonomic dysfunction originates from diabetes. And in this case, it will be enough to clearly control the level of sugar in the blood. If the reason is different, you can simply take control of those symptoms that, to one degree or another, lead to autonomic neuropathy:
- gastrointestinal system: drugs that save constipation and diarrhea; various exercises that increase mobility; maintaining a specific diet;
-skin: various ointments and creams that help relieve irritation; antihistamines to reduce itching;
- cardiovascular system: increased fluid intake; wearing special underwear; taking medicines that control blood pressure.
It can be concluded that the autonomic nervous system regulates the functional activity of almost the entire human body. Therefore, any problems that arose in his work should be noticed and studied by you with the help of highly qualified medical professionals. After all, the value of the ANS for a person is enormous - it is thanks to it that he learned to “survive” in stressful situations.
