Central Nervous System (CNS): parts, functions and diseases.

A summary of the classified parts and characteristics of the Central Nervous System.

The Central Nervous System (CNS) is responsible for controlling both voluntary and involuntary actions.. This includes not only the physical expressions, but also the acts of thought.

Thanks to this system we are able to respond in different ways to the ever-changing stimuli that our organism receives, as well as to coordinate the different physiological processes that keep us alive.

In this article we will review what the parts of the Central Nervous System (CNS) areWe will also see how they are classified, and the functions they perform in the human body, as well as some of the most common pathologies associated with these structures.

What are the parts of the central nervous system?

The Central Nervous System is composed of two indispensable structures not only for the correct functioning of the organism, but also for its life. These structures are the brain (understood as the encephalon, not only the cerebral cortex) and the spinal cord.. The first structure is inside the skull and includes parts such as the cerebellum, the cerebral cortex, the diencephalon, and other elements indispensable for our survival. The spinal cord projects along the spinal column, and communicates the brain and the nerves of the peripheral nervous system, which are not contained in bony parts and run throughout the body.

Now let's see what aspects each of these components is responsible for individually, and how they in turn are interconnected so that our organism reacts to any perceptible stimulus.

The Brain

This organ is undoubtedly the most complex in the human body in terms of its level of functioning. According to research in the field of neurosciences, the human brain is composed of approximately is composed of approximately 100 billion neurons, which interact with each other in a stablewhich interact with each other establishing an immeasurable number of connections. On the other hand, most of the brain's nerve cells are not neurons, but glial cells.

It is estimated that the brain consumes approximately 20% of all the oxygen we breathe. Its weight represents only a minimal 2% of the total weight of an average human being.

Now let's see what are the parts that make up the brain structure of human beings. First, we have the so-called cerebral lobes, which have different functions.which have different functions. These lobes of the brain are located in the cerebral cortex, which is composed mainly of gray matter, that is, areas in which there is a high concentration of neuronal somas.

The cortex is in charge of the more complex and abstract functions, such as imagination and thought, while the more primitive structures located below, such as the limbic system and the brainstem, are in charge of the most basic needs of the species; feeding, sexual reproduction, etc.

1. Frontal lobe

It is in charge of the higher functions of human consciousness.It is therefore one of the most important parts of the Central Nervous System. It is in charge of the rational part and the voluntary movements of the person. It is located in the forehead area.

2. Temporal lobe

It is in charge of memory, hearing, and language. It is located behind the ears.

3. Parietal lobe

It has to do with the perception of sensory stimuli coming from the environment, and also with the balance of the subject. It is located at the top of the head.

4. Occipital lobe

This lobe is in charge of receiving visual information and interpreting it.. It is located at the back of the head, a little above the nape of the neck, and is small compared to the rest of the brain lobes.

The spinal cord

This other part of the Central Nervous System (CNS) consists of a series of branches, which originate in the brain stem and descend along the spinal column.These nerve projections are arranged in the form of a relatively rectilinear column (along the spinal column), so that together they form something like a cord.

The main function of the medulla is to to connect the brain with the peripheral nervous system (PNS), both afferent and afferent.both afferently and efferently. This means that the brain can, through the spinal cord, send signals to the muscles located in the periphery through the nerves, and at the same time the external stimuli perceived from the periphery reach the brain.

Apart from these afferent and efferent functions, the spinal cord endows us with the ability to react involuntarily to some stimuli thanks to reflexes. For example, when you unintentionally touch something that is too hot, you involuntarily and quickly withdraw your hand from the object.

In short, this structure is in charge of the mobility of all the muscles necessary for us to be able to perform any activity; the brain intervenes only to start and stop such activity, or when an unforeseen event arises in the performance of such activity.

Diseases of the Central Nervous System

Taking into consideration that it is an extensive system, as it was evidenced, the pathologies that can present are just as wide. Now we will see some of the most common ones.

1. Cerebrovascular accident

It is a failure in the Blood irrigation to the brain.. This is interrupted for some reason, and therefore the neurons begin to die.

2. Trauma

A bad blow in the area of the head could cause a cerebral traumatism that affects punctually some lobe or another part of the brain and generate multiple complications.

3. Infections

Viruses that have the capacity to reach the Central Nervous System (CNS) represent a source of complications for its functioning, giving rise to pathologies such as meningitis or encephalitis.

4. Neurodegenerative diseases

Severe pathologies such as Alzheimer's disease or Parkinson's disease produce a lot of damage in many parts of the Central Nervous System.

Bibliographical references:

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