Parasympathetic nervous system
Synonyms in a broader sense
autonomic nervous system, spinal cord, nervous system
definition
The parasympathetic nervous system is the antagonist of the sympathetic nervous system and - like it - is part of the vegetative (also: autonomous) nervous system.
The autonomous nervous system is important for the control of our organs and glands, it is called autonomous because we cannot control it arbitrarily, it runs "alongside" without us being constantly aware of it (just think about breathing, digesting and Sweat)
The parasympathetic nervous system is the resting part of the autonomic nervous system. While the sympathetic nervous system prepares the body for stressful situations, it serves to "refuel" with energy and for relaxation. When the parasympathetic system becomes active, our body functions change as follows:
- Lowering blood pressure
- Decrease your heart rate per time and the force with which the heart pumps (i.e.: decreased heart rate and contraction force)
- Narrowing of the airways
- Constriction of the pupil
- decreased sweat secretion
- increased secretion of saliva
- increased digestive activity
So that explains how the parasympathetic nervous system works. Now it remains to be clarified where it is and how its effect comes about.
Localization of the parasympathetic nervous system
The Parasympathetic nervous system is - just like that Sympathetic - not a single place in the body, but rather distributed over a larger area. Understandable, because it has to reach many different organs. One can Place of origin, i.e. the cells from which the flow of information emanates from the Rail system, the cell processes, differentiate that brings the information to where it should go and act, namely to the Recipients, the organs.
The parasymapthicus is a craniosacral system. Its cells of origin are therefore in the head area (cranium (Latin) = skull) and in the area of the sacrum (Sacrum (Latin) = Sacrum), which is the lowest part of the Spine matters.
These cells of origin are Neurons (Neurons) with long appendages. There are two types of nerve cell extensions:
- the Axon, of which each neuron has at most one, is used to transmit information from the cell body to the periphery of the body
- the Dendrites, of which most neurons have a large number, serve to receive information in the periphery and transmit it to the cell body
The part of the parasympathetic nervous system that is in the head area is part of the cranial nerves. For a better understanding of the rest of the text, the cranial nerves should be briefly discussed here:
Excursus: cranial nerves
The cranial nerves are to the head what the spinal nerves are to the rest of the body. They are used to control the muscles (in the head this is especially the facial muscles, i.e. many small muscles in the facial area that allow us humans a pronounced range of facial expressions) and to perceive touch in the entire head area. They also convey smell, taste and hearing and seeing. They also control all of the glands in their supply area.
There are 12 cranial nerves, they are numbered with Roman numerals from I (1) to XII (12). Most of them have different qualities, i.e. a nerve not only has the task of perceiving touch, but also, for example, moving certain muscles. The following 4 cranial nerves have another task, they carry parasympathetic parts:
- III oculomotor nerve
- VII Facial nerve
- IX Glossopharyngeal Nerve
- X vagus nerve
What does that mean now? This is the said cranial system of the parasympathetic nervous system. The original cells of the cranial part reach their target organs via these 4 nerves.
The principle of parasympathetic parts the cranial nerve is always the same. The cells of origin lie in a cranial nerve nucleus (the place where the cranial nerves originate or end) with a certain name (because every cranial nerve has one or more cranial nerve nuclei), their processes pass through ganglion (With pseudounipolar Nerve cells) where they are switched and then run to their recipient. This recipient can be a gland or a muscle. In the head area, the recipients are not "whole" organs, like liver or kidney.
Since the following list of names of the various cranial nerve nuclei, Ganglia and the recipient is very specific detailed knowledge, it should only be in tabular form (see below) Find their way into this text.
