Meaning of Central Nervous System (What is it, Concept and Definition)

What is central nervous system:

The central nervous system (CNS) is a complex structure that humans and animals possess (vertebrates and almost all invertebrates), which is responsible for processing our thoughts and all the information we obtain through the senses.

It is composed of the brain and spinal cord, which are protected by the meninges and cerebrospinal fluid.

It is part of the nervous system, responsible for receiving and emitting stimulus signals throughout the body, along with the peripheral nervous system (SNP), composed of sensory nerves and nodes that connect to the central nervous system.

In the central nervous system the mental processes necessary to understand the information we receive from outside are carried out. It is also the system responsible for transmitting certain impulses to the nerves and muscles, so it directs its movements.

In this way, the central nervous system uses neurons (sensory and motor) of the brain and spinal cord to cause precise responses to the stimuli the body receives. Therefore, for example, you can change behaviors, even taking into account past experiences.

The importance of the central nervous system is in the ability to control bodily functions, to develop knowledge, learning, distinguish emotions, among others, specially developed by the human being. That is, the central nervous system allows us to recognize ourselves as individuals, to be aware of who we are, what we do and feel.

Parts of the central nervous system

Below are the parts of the central nervous system and their functions.


The brain is a nerve mass that is protected by the bones of the skull. The brain is characterized by being the center of control of the body by regulating our hunger, sleep, movements, even emotions (love, hate, sadness, joy, among others). The brain is composed of the brain, cerebellum and brain stem.

The brain is the most voluminous and important mass of the brain because it fulfills various vital functions in vertebrate animals (especially in humans) and invertebrates, and that is protected by the bones of the skull.The cerebral cortex is characterized by being formed by numerous folds composed of gray matter, under which the white substance is also found, and in the deepest areas the thalamus, caudate nucleus and hypothalamus are distinguished.

In turn, two parts of the brain called hemispheres are distinguished: the right hemisphere and the left hemisphere, which communicate through the corpus callosum.

The hemispheres have fissures (deep grooves in the cerebral cortex), which demarcate the lobes of the brain that are: frontal lobe, temporal lobe, parietal lobe and occipital lobe.


The cerebellum is located at the back of the brain, behind the brain, and connects to the spinal cord. He is responsible for relating the sensory and motor pathways. Therefore, it is possible to maintain posture and body balance, coordinate various motor movements such as walking, writing, running, speaking, among others, as well as muscle tension.

Brain stem

The brain stem or brainstem is the one that joins the brain with the spinal cord, so it is responsible for controlling various functions such as breathing or heart rate. The brain stem is composed of:

  • Midbrain: controls eye movements and regulates the reflections of the eyes, head and neck.
  • Ring ExtrusionA: It works as a sensitive pathway that leads sensations from the cord to the brain, and vice versa. It is also a structure that allows us to maintain body balance.
  • Spinal bulb: controls the heart rate, blood pressure and intervenes in the respiratory rate. It also controls swallowing, vomiting, sneezing and cough.

Spinal cord

The spinal cord is a cord that extends from the brain throughout the inner part of the spine. Its main function is to transmit nerve impulses and connect the brain with the rest of the body. It is characterized by having the white substance on the outside and the gray substance on the inside.

In the spinal cord two functions of great importance are carried out, the sensitive affinity that consists in receiving the sensory stimuli that reach the spinal cord, and the efferent one, which is related to motility, that is, it sends information to the nervous system peripheral.

In this sense, it is in the spinal cord that information is received and sent to the whole body, therefore it is responsible for various reflex arcs and for conducting nerve impulses.