Central Nervous System (Meaning and Explanation)

We explain what the central nervous system is and what its functions are. Also, what are neurons and their structure.

What is the central nervous system?

The central nervous system (CNS) is a complex structure that is present in humans and animals and that It has the function of coordinating, integrating and controlling the organism.

It is made up of the brain (located in the skull) and the spinal cord (located within and throughout the entire spinal column) and is what allows you to perform functions such as movement learning, breathing, among many others.

The central nervous system receives information, from external or internal stimuli, which it processes through cells called neurons and develops responses. Also is responsible for the organization of the different devices such as respiratory or digestive.

Together with the peripheral nervous system, the central nervous system forms the nervous system of organisms. The peripheral nervous system has the function of transporting stimuli from the senses to the central nervous system.

The neurons

Neuron - Central nervous system — Dendrites are nerve centers that receive information from other neurons.

The neurons are cells that are part of the nervous system of organisms and they have the function of receiving, processing and transmitting information through nervous impulses. These cells connect to each other and allow information to travel from one place in the body to another.

The connection process between neurons is known as synapses and it uses neurotransmitters, which are chemical substances that allow the transmission of nervous impulses between one neuron and another.

Neurons have a shape that differs from traditional cells, since they are made up of a soma or body. This soma has a rounded shape and is covered with hairs called dendrites, which are nerve centers that receive information from other neurons.

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From the soma comes an axon, which is a long, thin connection that allows information to travel. The information that leaves the axon reaches the dendrites of another neuron which receives it, processes it in its soma and sends it through its axon to the dendrites of another neuron.

The distinctive characteristic of neurons is that information travels extremely quickly, through nerve impulses, thanks to the myelin that covers the axon.

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Structure of the central nervous system

The central nervous system is subdivided into two parts: one that is inside the skull (the brain) and the other inside the vertebral column (the spinal cord).

brain. It is an organ that is part of the central nervous system and is located in the cerebral cortex. It is responsible for regulating most vital functions such as appetite, vision, emotions, thinking, among others. In humans and vertebrates the brain is divided into:

Forebrain. It is also called the prosencephalon.
midbrain. It is also called the midbrain and is the upper structure of the brain stem.
Hindbrain. It is also known as the hindbrain and is located at the top of the spinal cord. In turn, it can be subdivided into three parts:
- Bulb
- Annular protuberance
- Cerebellum

Spinal cord. It is a nervous tissue that has a cylindrical and flattened structure and extends from the base of the skull to almost the end of the spinal column.
The spinal cord carries nerve impulses to the spinal or spinal nerves, that is, its function is to communicate the brain with the rest of the body. Therefore, the spinal cord sends information from the brain to, for example, the muscles, or from the muscles to the brain. It is also responsible for executing reflex acts.

Functions of the central nervous system

The central nervous system is the person in charge of regulating all activities carried out within the organization and process the information that comes in from the senses.

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This involves the development of ideas, thoughts, memories, emotions. Besides, regulates and sends the signal that activates the body's movements sleep, wakefulness, the functioning of organs such as the heart, functions such as eating, drinking, among many others.

The highest level in the central nervous system is the one in the cerebral cortex. Higher functions such as conscious perception are organized in the cortex memory, language and reasoning. Then there are the cerebellum and the basal ganglia, which are responsible for consciously controlling movement.

For its part, the brain stem is responsible for involuntary functions such as maintaining balance, controlling pressure in the body, executing automatic movements such as breathing or heartbeat, chewing, among others.

Then there are the functions carried out by the spinal cord, which are:

Afferent functions. Its function is to transmit the sensations of the trunk, neck and four limbs to the brain.
efferent functions. They are the orders that come from the brain to the spinal cord, which tells the different organs to carry out a certain action.

Importance of the central nervous system

The central nervous system is a vital structure for the correct development of organisms. It is through it that the individual connects and relates to the environment that surrounds him, since he receives the stimuli (which he captures through the senses) and the central nervous system is responsible for interpreting them and giving the signal for the execution of a response.

Furthermore, the central nervous system regulates voluntary and involuntary processes that occur in the body and they are those that allow correct balance and development, such as breathing, digestion or movement. A disorder in any of the areas involved in the nervous system implies an alteration in its correct functioning.

To maintain a balanced nervous system, it is important to take care of the state of neurons, which are cells that disappear over time, although they can regenerate (neurogenesis). Good nutrition, rest and physical activity protect neurons from early deterioration.

Diseases of the central nervous system

There are certain diseases and pathologies that can affect the correct performance of the central nervous system. Some are:

Epilepsy. Disorder of the central nervous system in which mental activity is altered, causing seizures.
Amyotrophic lateral sclerosis. Disorder in which the wear or loss of neurons occurs, which reduces or paralyzes muscle activity.
multiple sclerosis. Disorder in which the protective layer that covers the nerves degrades, making the connection between the brain and the rest of the body difficult.
Monoplegia. Type of brain disorder that occurs when some part of the central nervous system is injured, causing a connection problem and affecting muscle movement. In monoplegia, one limb of the body is affected.
Hemiplegia. Type of brain disorder that occurs when some part of the central nervous system is injured, causing a connection problem and affecting muscle movement. In hemiplegia, one side of the body is affected.
Tetraplegia. Type of brain disorder that occurs when some part of the central nervous system is injured, causing a connection problem and affecting muscle movement. In tetraplegia, both arms and both legs are affected.
Parkinson's disease. Disorder that occurs in the central nervous system that produces tremors and affects movement.
Alzheimer's disease. Disorder in which neurons degenerate, causing alterations in memory and language.
Huntington's disease. Disorder in which neurons degenerate, causing alterations in movements and cognitive damage.
Meningitis. Infection that occurs when a virus or bacteria attacks the membranes of the spinal cord and brain. This causes discomfort, fever and neck and back pain.