Parts of the Nervous System: functions and structures

Like other 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 to it being considered the most complex structure of all that work in the human body. But that it is complicated to understand does not mean that we cannot understand, at least superficially, how it is and how it works. We'll see now what are the parts of the nervous system and what are their tasks.

• Related article: "Parts of the human brain (and functions)"

What is the Nervous System and what parts does it have?

The nervous system has the function of organize, coordinate and govern the tasks that the human body carries out, becoming a kind of internal network that encompasses the entire body. For this, it uses a grouping of organs and structures whose fundamental task is to collect and process stimuli and signals, coming from both inside and outside, in order to achieve an adequate interaction with everything that surrounds the person.

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

In addition, this nervous tissue is made up of cells called neurons, which are cells specialized in communicating through chemical and electrical signals that run through everything the human body until it reaches the brain, which processes them and sends a fly response to the rest of the organism.

It has been found that the number of neurons that make up the brain is around 100.00 million.

There are several ways to study and divide the human nervous system, 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 includes the brain and the spinal cord; and the peripheral nervous system (PNS) which is made up of all the nerves that start from the CNS and extend throughout the body.

• Related article: "Types of neurons: characteristics and functions"

The central nervous system (CNS)

The central nervous system has a series of peculiarities of its own. Some of these are:

• Your most important organs are highly protected of the external environment, specifically by three membranes called meninges.
• The functional cells of the central nervous system are grouped into two different organizations: the white matter and the Gray matter.
• The means of transmitting information is through small orifices located in the brain and spinal cord, within which is the cerebrospinal fluid.

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

1. Brain

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

From the anatomical point of view the brain includes the cerebrum, cerebellum, and brainstemThese are also made up of other structures that are explained below.

1.1. Brain

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

The brain is divided into two great hemispheres, the left and right hemispheres, and in the middle of which is the interhemispheric fissure. Also, these two hemispheres communicate through a bundle of nerve fibers called the corpus callosum.

The outer area of ​​the brain It is known as the cerebral cortex, formed from matter and gray, which takes the form of folds called convolutions. Under this layer of gray matter is white matter. What's more. gray matter is also part of other structures such as the thalamus, the caudate nucleus and the hypothalamus.

Among many other functions, the brain is in charge of 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 in charge of de integrate the sensory and motor processes of the human body.

This is connected to other brain structures and to the spinal cord by an infinite number of bundles. nervous, so that it manages to participate in all the signals that the cortex sends to the system locomotor.

In addition, recent studies have shown that the cerebellum may be involved in other functions, including those related to the cognitive and language processing, learning, and even in the processing of other sensory stimuli such as music.

• Related article: "Human cerebellum: its parts and functions"

1.3. Brain stem

Also known as the brainstem or brainstem, this is the main communication route between the brain, the spinal cord and the peripheral nerves. Likewise, this system made up of gray and white matter is capable of controlling various tasks such as breathing or heart rate.

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

• Related article: "Brainstem: functions and structures"

2. Spinal cord

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

There are two main routes through which information passes:

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

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

Peripheral nervous system

The peripheral nervous system is responsible for transmit the signals through the spinal and spinal nerves, which are 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 made up of cranial and spinal nerves.

• You may be interested: "Peripheral nervous system (autonomic and somatic): parts and functions"

3. Cranial nerves

The cranial nerves are made up of 12 pairs of nerves, hence they are also known as cranial nerves. These originate in the brain and at the level of the brain stem, spreading throughout the body through holes located at the base of the skull, in the neck, chest and abdomen.

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

While the fibers responsible for sensory and sensory signals, which cross the afferent pathway, are born outside the brain stem.

4. Spinal nerves

The spinal nerves or spinal nerves, are 31 pairs of nerves that are 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 information on posture, musculature, and joints, then 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 of its pathways; separating between somatic nervous system, responsible for intermediating between the internal organism and the external environment; and the autonomic nervous system or vegetative, which mediates the connections and internal communication of the body.