The human autonomic nervous system has a direct effect on the functioning of many internal organs, as well as 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 "secretive", that is, no one can clearly feel the 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 units
The main task of human NS is to create an apparatus, which would connect all the organs and systems of the human body together. Thanks to this, he 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 autonomous (autonomic) nervous systems.
The first was created mainly so that the human body could be in contact with the external environment. Therefore, this system has its second name - animal (i.e., animal), due to the performance of those functions that are inherent in them. The value of the
autonomic nervous system is no less important for a person, but the essence of its work is completely different - control over those functions that are responsible for respiration, digestion and other roles inherent mainly to plants (hence the second name of the system - autonomous).
What is the autonomic nervous system of a person?
The ANS operates with the help of neurons (a set of nerve cells and their processes). They, in turn, work due to the fact that they send certain signals to various organs, systems and glands from the spinal cord and brain. It is interesting that neurons of the vegetative part of the human nervous system are responsible for the work of the heart (its reduction), the functioning of the digestive tract (intestinal motility), and the activity of the salivary glands. Actually, therefore, 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 animals and humans. The neurons that make up the core of the ANS are able to create some clusters located in the brain and spinal cord. They were given the name "vegetative kernels." Also, near the organs and spine, the vegetative part 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 are peripheral. In fact, the ANS is divided into two parts: parasympathetic and sympathetic.
What role does ANS play in the human body?
Often people cannot answer a simple question: “Does the autonomic nervous system regulate what: muscles, organs or systems?”
In fact, it, in fact, is 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, the regulation of the normal internal state of a person (blood circulation, respiration, secretion, hormone levels, etc.) is the main role of the autonomic nervous system. In addition, it is capable of exerting the most direct influence on other components of the human body, for example, muscles (cardiac, skeletal), various sensory organs (for example, the expansion or contraction of the pupil), endocrine glands, and much more. The autonomic nervous system regulates the functioning of the human body through various effects on its organs, which can be arbitrarily represented by three types:
- metabolic control in the cells of various organs, the so-called trophic control;
- an indispensable effect on the functions of organs, for example, on the work of the heart muscle - functional control;
- effect on organs due to an increase or decrease in their blood flow - vasomotor control.
The composition of the human ANS
It is important to note the main thing: the ANS is divided 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 sweating, increased pupils, and weak intestinal motility. The parasympathetic nervous system works in a completely different way, i.e., in the opposite way. She is characterized by such actions in the human body, in which he rests and assimilates everything. When it begins to activate the mechanism of its work, the following processes are observed: pupil constriction, decreased sweat, 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 departments studied above. Their interconnected work allows you to maintain the human body in balance. In simpler terms, the data components of the ANS must exist in a complex, constantly complementing each other. This system works only due to the fact that the parasympathetic and sympathetic nervous systems are able to release neurotransmitters, which bind organs and systems with the help of nerve signals.
Control and verification of the autonomic nervous system - what is it?
The functions of the autonomic nervous system are under the continuous control of several major centers:
- Spinal cord. The sympathetic nervous system (SNS) creates elements located in close proximity to the trunk of the spinal cord, and its external components are represented by the parasympathetic division of the ANS.
- The brain . It has the most direct effect on the functioning of the parasympathetic and sympathetic nervous systems, regulating the balance throughout the human body.
- The brain This is a kind of connection that exists between the brain and spinal cord. He is able to control the functions of the ANS, namely its parasympathetic department (blood pressure, respiration, heart contractions and more).
- The hypothalamus is part of the diencephalon. It affects sweating, digestion, heartbeats, 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.
ANS functions
They arose thousands of years ago when people learned to survive in difficult conditions. The functions of the autonomic nervous system of a person are directly related to the work of its two main departments. 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). Thus, the emotional state is balanced. 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 due to 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 intensifies, and much more. These processes help a person to survive stressful situations. Therefore, we can conclude that the autonomic nervous system regulates the work of the human body as a whole, one way or another influencing 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 intestines (its peristalsis), by reducing the flow of blood 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 narrowing of blood vessels, an increase in blood pressure;
- normalizes the level of glucose in the blood due to its decrease in the liver.
It is also known that the autonomic nervous system regulates the work of skeletal muscles - this is directly dealt with by its sympathetic department.
For example, when your body experiences stress in the form of an elevated temperature, the sympathetic division of the ANS immediately acts as follows: it transmits the corresponding signals to the brain, and it, in turn, increases the sweating or expands the skin pores using nerve impulses. Thus, the temperature is significantly reduced.
Parasympathetic Nervous System (PNS)
This component of the ANS is aimed at creating a state of rest, calmness, and assimilation of all vital processes in the human body. His work boils down directly to the following:
- enhances the work of the entire digestive tract, increasing blood flow to it;
- acts directly on the salivary glands, stimulating the production of saliva, thereby accelerating intestinal motility;
- reduces the size of the pupil;
- exercises the most stringent control over the work of the heart and all its departments;
- reduces the size of bronchioles when the level of oxygen in the blood becomes normal.
It is very important to know that the autonomic nervous system regulates the functioning of the muscles of various organs - this issue, in particular, also deals with its parasympathetic department. For example, the contraction of the uterus during excitation or in the postpartum period is associated precisely with the work of this system. And an erection in a man is subject only to her influence. After all, with the help of nerve impulses, blood flows to the genitals of a man, to which the muscles of the penis react.
How does a stressful situation affect ANS?
I want 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 human life (a huge stone falls on him, or a wild animal suddenly appeared in front of him). Someone immediately runs away, and the other simply freezes in place without the ability to move off the ground. It does not depend on the person himself, so he reacted at an unconscious level to his ANS. And all this is due to 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, cardiovascular apparatus, reproduction, activity of the lungs and urinary tract. Therefore, in the human body there are many centers that can respond to stress through the work of the ANS. But do not worry much, since most of our lives we do not experience strong shocks, therefore the occurrence of such conditions is rare for a person.
Deviations in human health caused by malfunctioning ANS
Of course, from the foregoing, it became clear that the autonomic nervous system regulates the work of many systems and organs in the human body. Therefore, any functional impairment in its work can significantly disrupt this workflow.
By the way, the causes of such disorders can be either heredity or diseases acquired in the process of life. Often the work of the ANS of a person is “invisible” in nature, but problems in this activity are noticeable based on the following symptoms:
- nervous system: the inability of the body to reduce body temperature without unnecessary help;
- Gastrointestinal tract: vomiting, constipation or diarrhea, inability to swallow food, urinary incontinence and much more;
- skin problems (itching, redness, peeling), brittle nails and hair, increased or decreased sweating;
- vision: blurry pictures, lack of tears, difficulty in focusing;
- respiratory system: an incorrect reaction 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 tract system: medicines that relieve 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 medications 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 workers. Indeed, the importance of ANS for a person is enormous - it was thanks to her that he learned to “survive” in stressful situations.