Help the development of the site, sharing the article with friends!
The somatic system (somatic nervous system) is one of the distinguished functional parts of the nervous system - generally speaking, it is responsible for receiving sensations from the external environment and for performing planned, dependent on our will, activities. But what exactly does the somatic nervous system make?
The somatic nervous system , or, for short,the somatic system , is not a distinct anatomical structure. Responsible for sensing external stimuli and making conscious, voluntary movements.
The human nervous system is such a complex structure that it is not surprising that it is also quite complex and its divisions are distinguished by at least several of them. In basic terms, the central nervous system and the peripheral nervous system are distinguished, but taking into account whether we have an influence on the functions performed by certain parts of the nervous system, the autonomic and somatic nervous systems can be distinguished.
The first of these (which includes the sympathetic and parasympathetic systems) controls the course of processes completely independent of our will, while the somatic nervous system functions in the opposite way, the operation of which depends to a large extent on our will.
Somatic system: structure
The somatic nervous system is considered part of the peripheral nervous system. It includes various receptors that are scattered throughout the body - examples of them include mechanoreceptors, receptors responsible for the reception of thermal stimuli or pain receptors.
The receptors themselves, however, are not sufficient for the information they receive to reach the higher centers of the nervous system - it is sent to them via sensory (afferent, afferent) nerve fibers.
Above, however, only those elements that are responsible for transmitting the received information have been mentioned, while the somatic nervous system is also responsible for the execution of movements planned by us. This possibility is provided by motor fibers (efferent, centrifugal), which send nerve impulses from various centers of the nervous system (e.g. from the spinal cord) to the executive organs (effectors, which may be, for example, muscle cells).
Basically forthe basic unit building the somatic system can be considered nerve fibers - in this case, there are 12 pairs of cranial nerves, derived directly from the structures of the brain, and 31 pairs of spinal nerves (in their case, one pair of nerves depart from each of the 31 segments of the spinal cord).
Somatic system: functions
As can be deduced from the above description, the functions of the somatic nervous system can be divided in two ways: they are receiving various sensory stimuli (this is what the sensory part of this system deals with) and performing purposeful, dependent on our will movements (the motor part is responsible for this). of the somatic system, which includes elements of the pyramidal system and the extrapyramidal system).
Generally, the somatic nervous system records and processes sensations from the aforementioned receptors, but it is also what makes us perceive impulses reaching our sensory organs. It is also responsible for the activity of the glands that are present in our skin.
The somatic nervous system also innervates skeletal muscles, the activity of which depends on our will - when we decide to reach for a glass of water, the impulses leading to such a movement are sent with precisely those fibers that belong to the somatic system nervous.
It is described all the time here that the somatic nervous system is involved in the execution of movements planned by us, depending on our will. It is indeed so, but it is not the only task that this structure performs - besides, the nerve fibers belonging to it are related to various reflex activities.
Somatic system: diseases
In fact, the somatic nervous system is not some structural, clearly separated part of the nervous system, but only distinguishes it on the basis of its functions, therefore it is difficult to clearly define which pathologies may apply to it. In general, problems of the somatic nervous system include:
- Guillain-Barré syndrome
- nerve fiber entrapment syndromes (e.g. carpal tunnel syndrome)
- myasthenia gravis
- neoplasms that develop within the somatic nervous system (such as optic glioma or neuroblastoma)