Parts of the Nervous System: functions and anatomical structures.

A summary of the characteristics of the nervous system, from the brain to the nerves.

Like the rest of animals, the human being is capable of perceiving and assimilating information both from the external space that surrounds him and from his own interior; capturing, consciously or unconsciously, the signals that the body itself emits from any part of it.

The nervous system is in charge of receiving and emitting these signals, managing and organizing the various tasks and activities of the body. This task has led it to be considered the most complex structure of all those working in the human body. But the fact that it is complicated to understand does not mean that we cannot understand, at least superficially, how it is and how it works. In the following we will see what are the parts of the nervous system and what are their tasks?.

What is the Nervous System and what are its parts?

The nervous system has the function of organize, coordinate and govern the tasks that the human body carries out, constituting a kind of internal network that covers the whole body.It is a kind of internal network that covers the whole body. To do so, it uses a group of organs and structures whose fundamental task is to collect and process stimuli and signals from both the inside and the outside, in order to achieve an adequate interaction with everything that surrounds the person.

All this set is originated from nervous tissue of ectodermal origin, which means that it is part of all those parts of the body that were first formed in the embryo.

Likewise, this nerve tissue is made up of two types of nerve cells. First, cells called neuronsneurons, which are cells specialized in communicating by means of chemical and electrical signals that travel throughout the human body until they reach the brain, which processes them and sends a flight response to the rest of the organism.

It has been found that the number of neurons that make up the brain is around 100,000 million.

Secondly, there are the so-called glial cells, which are the most numerous and have the largest number of neurons.These are the most numerous and have different functions, but in general they maintain and help the neurons to survive and move, either by facilitating their transmission of electrical signals or by providing them with the substances they need and giving them structural support to go from one part of the nervous system to another.

There are several ways to study and divide the human nervous system, and this article will focus on the anatomical point of view. From this perspective, this complex structure is formed by the central nervous system (CNS), which comprises the brain and the spinal cord; and the peripheral nervous system (PNS), which is composed of all the nerves that start from the CNS and extend throughout the body.

The central nervous system (CNS)

As its name indicates, this element of the human body can be considered the "core" of the nervous system, the part in which all the processes that allow the existence of the nervous system and its most important processes are integrated.

On the other hand, the central nervous system has a number of peculiarities of its own. Some of these are:

• Its most important organs are highly protected from the external environment, specifically by three membranes called meninges.
• The functional cells of the central nervous system are grouped together to form two different organizations: the white matter and the gray matter.
• The means of transmission of information is through small orifices located in the brain and the medulla, within which the cerebrospinal fluid is found.

As we saw earlier, the central nervous system is made up of two different structures: the brain and the spinal cord.

1. Encephalon

The encephalon is the structure of the central nervous system that is located inside the skull.. This set of organs dominates all aspects of the body, including all voluntary and involuntary functions that a person can do.

From an anatomical point of view the encephalon includes the cerebrum, the cerebellum and the brain stem.These are also made up of other structures which are explained below.

1.1. Cerebrum

It is the best known organ of this system and also the one with the largest size.

The brain is divided into two large hemispheres, the left and right hemispheresThe brain is divided into two large hemispheres, the left and right hemispheres, in the middle of which is the interhemispheric fissure. These two hemispheres communicate by means of a bundle of nerve fibers called the corpus callosum.

The outer area of the brain is known as the cerebral cortexThe outer area of the brain is known as the cerebral cortex, formed from gray matter, which takes the form of folds called convolutions. Beneath this layer of gray matter is the white matter. In addition, the gray matter also forms part of other structures such as the thalamus, the caudate nucleus and the hypothalamus.

Among many other functions, the brain is responsible for processing information from the different senses, as well as controlling movement, cognition, emotions, memory and learning.

1.2. Cerebellum

Located in the lower and posterior part of the brain, the cerebellum is responsible for integrating the sensory and motor processes of the human body. integrating the sensory and motor processes of the human body..

It is connected to other encephalic structures and the spinal cord by means of an infinity of nerve bundles, so that it manages to participate in all the signals that the cortex sends to the locomotor system.

Recent studies have also revealed that the cerebellum may be involved in other functions, including cognitive and language processing, learning, and even in the processing of other sensory stimuli such as music.

1.3. Brain stem

Also known as the brainstem or brain stem, this is the major communication pathway between the brain, spinal cord and peripheral nerves. Likewise, this system formed by gray and white matter is capable of controlling various tasks such as breathing or Heart rate.

The structures that form part of the brainstem are the midbrain, pons and medulla oblongata. the midbrain, the pons and the medulla oblongata, also known as the medulla oblongata.also known as the medulla oblongata.

Spinal cord

The spinal cord has the fundamental mission of transport the nervous impulses from the brain to the 31 pairs of nerves of the peripheral nervous system. of the peripheral nervous system.

There are two main pathways through which the information passes:

• Afferent pathway: in which information circulates from the trunk, neck and the four extremities to the brain.
• Efferent pathway: signals travel from the brain to the rest of the body.

Also, some of its other tasks involve the command of vegetative and immediate movements.

Peripheral nervous system

The peripheral nervous system is responsible for transmitting signals via the spinal and transmitting signals through the spinal and spinal nerves, which are outside of the central nervous systemThese are located outside the central nervous system but have the purpose of connecting it with the rest of the structures and systems.

If we continue with the anatomical classification, the PNS is composed of cranial and spinal nerves.

Cranial nerves

The cranial nerves are composed of 12 pairs of nerves, hence they are also known as cranial nerves. They originate in the brain at the level of the brain stem and are distributed throughout the body by means of orifices located at the base of the skull, in the neck, thorax and abdomen.

These nerves are born located according to the work they are going to perform. Those in charge of transmitting motor information travel along the efferent pathway and originate in the brainstem.and have their origin in the brainstem.

While the fibers in charge of sensory and sensory signals, which cross the afferent pathway, are born outside the brainstem.

4. Spinal nerves

The spinal nerves, or spinal nerves, are 31 pairs of nerves responsible for transmitting sensory signals, such as touch or pain, from the trunk and the four limbs to the central nervous system.. In addition, they mediate postural, muscle and joint information, thus carrying information from the SCN to the rest of the body.

There is another classification of the peripheral nervous system according to the function of each one of its pathways; separating between the somatic nervous systemThe autonomic or vegetative nervous system, responsible for mediating between the internal organism and the external environment; and the autonomic or vegetative nervous system, which mediates the body's internal connections and communication.