Sympathetic Nervous System (Characteristic and Function )
Present ourselves to an opposition, react to a car that rushes at us, discover that the alarm has not sounded in the morning, escape from someone who bothers us or threatens us ... All those situations characterized by stress, anxiety or clear feeling of danger are regulated by that complex and fascinating structure: the sympathetic nervous system.
In our day to day, we are hardly aware of the large number of situations in which this structure acts. It is not necessary for a real or tangible risk to occur before us.
Factors such as daily stress or the mere pressure that usually accompanies almost implicitly to each of our days reflect something admirable: we are organisms designed to make our way, to survive, to have control (or at least try) those elements of our environment that are significant.
So, common situations such as running to catch the subway and not being late for work, react in time for that cup does not fall on the floor, so that our cat does not escape through the door or our son does not take that so dangerous to the mouth are examples of the importance of said structure.
What we experience in those moments is also well known. The heart accelerates, our muscles tighten and we are able to perform movements very quickly in a matter of seconds. All this physiological process before any stimulus and situation of high emotional connotation is orchestrated by this system. Let's see more data below.
"Life is only bearable when the body and soul live in perfect harmony, there is a natural balance between them and they respect each other".
-David Herbert Lawrence-
What is the sympathetic nervous system?
The sympathetic nervous system is one of the branches of the autonomic nervous system. Recall, first of all, that we are facing a type of structure that is responsible for a large number of involuntary functions. That is, tasks such as controlling heart rate, digestion, sweating, etc. they are dimensions that regulate both the sympathetic nervous system, as the parasympathetic or the enteric.
- Now, the sympathetic nervous system is responsible for a series of very specific tasks: regulate and activate our reflexes and reactions. It is, as we have already indicated, that organic center that allows us to react to any "non-neutral" emotional stimulus. As it is, for example, any situation of stress, whether mild or intense, as revealed by a study carried out by the Welfare University in Osaka.
- In turn, it is made up of a chain of 23 glanglia that start from the medulla oblongata and that connect to both sides of the spinal cord and to the organs that innervate it.
- On the other hand, this system is made up of two types of neurons. The first are the preganglionic, which are connected to the spinal cord and the ganglion itself. Thus, in order to carry out their functions they need a very specific neurotransmitter: acetylcholine.
- For its part, the other type of neuron that governs the sympathetic system is the postganglionic, which needs noradrenaline to communicate between the ganglion and the organ that inerve (heart, liver, stomach, intestines, lungs, etc.).
The sympathetic system areas
On the other hand, it is important to know how the sympathetic system is structured. We know how it connects, let's see how it is distributed:
- Departure area: the sympathetic system starts, as we have indicated, from the medulla, a nucleus that regulates a wide spectrum of functions unconscious for us, but vital for our existence.
- The cervical sympathetic area, where all the nervous formation of the head and neck are located.
- Superior cardiac area, with all the visceral vascular branches relative to the carotid plexuses, the submaxillary zone, the pharynx, larynx, etc.
- The thoracic sympathetic area: a region that encompasses each side of the spine, including joints, intercostal nerves, etc.
- The lumbar area, including the psoas muscle, the inferior vena cava, etc.
- Pelvic area, which runs from the areas of the sacrum to the rectum.
What happens in your body when the sympathetic nervous system is activated?
For every person who suffers stress in their day to day, it will be of great interest to know what happens in their own body in these situations. Moreover, if we suffer from something as common as hypertension it can also be relevant to know how the sympathetic nervous system mediates in this case in relation to our health. In fact, studies like the one carried out in the Journal of Human Stress explain how this link is shaped and what differences exist even between men and women.
However, the mechanism of action of the sympathetic system in any situation of danger or anxiety is one of the most complex yet striking processes. Let's see how it reacts to a threatening stimulus:
- It promotes the release of adrenaline and noradrenaline in the blood through the kidneys. The purpose of this is simple: we need more energy and activation to be able to react, and this energy requires, for example, that the liver produce more glucose.
- Increase heart rate to provide more oxygen and nutrients through the blood.
- Bronchodilation occurs: that is, we need more oxygen and our lungs work at peak performance.
- All activities related to digestion slow down. We can not forget that this process requires great energy and in times of stress and alarm, this task is secondary. The only thing the brain wants is for us to react, to face that stimulus or to run away.
- In turn, and no less interesting, the sympathetic system produces mydriasis or pupillary dilation. In this way, this unconscious reaction allows us to increase the visual field and react with greater security.
Neurology - Autonomic Nervous Sistem
To conclude, as the philosopher Henri-Frédéric Amiel said, our body is the perfect temple of nature. It is something that has been given to us, however, it is our obligation to take care of it and also to study it. Only then can we come to understand ourselves better, to understand why we are the way we are and why certain problems or conditions arise when we least expect it.