home Diseases CNS (central nervous system), its departments, functions. Structure and functions of NS Development. Nervous tissue The highest division of the human central nervous system is

CNS (central nervous system), its departments, functions. Structure and functions of NS Development. Nervous tissue The highest division of the human central nervous system is

The central nervous system is the basis of the entire nervous system of the human body. All reflexes and the functioning of vital organs are subordinated to it. When a patient is diagnosed with disorders in the central nervous system, not everyone understands what is included in the human nervous system. All living creatures have it, but the central nervous system has some peculiarities, for example, in humans and other vertebrates it consists of the brain and spinal cord, which are protected by the skull and spine.

Structure

The human central nervous system consists of two brains: the brain and the spinal cord, which are closely interconnected. These will be discussed in more detail below. The main function of the central nervous system is to control all vital processes occurring in the body.

The brain is responsible for mental function, the ability to speak, auditory and visual perception, and it also allows for the coordination of movements. The spinal cord is responsible for regulating the functioning of internal organs and also allows the body to move, but only under the control of the brain. Due to this, the spinal cord acts as a carrier of signals transmitted from the head to all parts of the body.

This process is carried out due to the neural structure of the brain matter. A neuron is the basic unit of the nervous system that has an electrical potential and processes signals received from ions.

The entire central nervous system is responsible for the following components that help adapt to the outside world:

The human central nervous system is made up of gray and white matter.

The first of these are nerve cells that have small processes. The gray substance is located in the very center of the spinal cord. And in the brain it is this substance that represents the cortex.

The white matter is located under the gray matter and contains nerve fibers that form bundles that make up the nerve itself.

Both brains, based on anatomy, are surrounded by the following membranes:

Arachnoid, located under the hard part. It contains a vascular network and nerves.
Hard, representing the outer shell. It is located inside the spinal canal and skull.
Vascular, connected to the brain. This membrane is formed from a large number of arteries. It is separated from the arachnoid by a special cavity, inside which the brain matter is located.

This structure of the central nervous system is inherent in humans and all vertebrate animals. As for chordates, their central nervous system has the form of a hollow tube called a neurocoel.

Spinal cord

This component of the system is located in the spinal canal. The spinal cord extends from the occipital region to the lower back. There are longitudinal grooves on both sides, and in the center there is a spinal canal. On the outside there is white matter.

As for the gray substance, it is part of the anterior, lateral and posterior horny areas. The anterior horns contain motor nerve cells, and the posterior horns contain intercalary nerve cells intended for contact between motor and sensory cells. The anterior ones are joined by processes that make up the fibers. The neurons that create the roots connect to the horny areas.

They are intermediaries between the spinal cord and the central nervous system. Excitation passing into the brain comes to the interneuron, and then, with the help of an axon, to the necessary organ. Sixty-two nerves extend from each vertebra in both directions.

Brain

Conventionally, we can say that it consists of five sections, and inside it there are four cavities filled with a special fluid called cerebrospinal fluid.

If we consider an organ based on the principle of the size of its components, then the hemispheres are rightfully considered to be the first, occupying eighty percent of the total volume. The second in this case is the trunk.

The brain consists of the following areas:

Average.
Rear.
Front.
Oblong.
Intermediate.

The first of these is located in front of the pons, and it consists of the cerebral peduncles and four colliculi. In the very center there is a canal that is the connecting link between the third and fourth ventricles. It is framed by a gray substance. The cerebral peduncles contain pathways that connect the cerebral peduncles and the pons oblongata with the cerebral hemispheres. This part of the brain realizes the ability to transmit reflexes and maintain tone. With the help of the middle section, standing and walking become possible. Also located here are the nuclei associated with vision and hearing.

The medulla oblongata is a continuation of the spinal cord; it is even similar in structure to it. The structure of this section is formed of white matter, where there are areas of gray from which the cranial nerves arise. Almost the entire department is covered with hemispheres. The medulla oblongata contains centers responsible for the functioning of such important organs as the lungs and heart. In addition, it controls swallowing, coughing, the formation of gastric juice and even the secretion of saliva in the mouth. If the medulla oblongata is damaged, death can occur due to cardiac and respiratory arrest.

The hindbrain includes the pons, which looks like a splenium, and the cerebellum. Thanks to the latter, the body is able to coordinate movements, keep muscles toned, maintain balance and move.

The diencephalon is located in front of the cerebral peduncles. Its structure includes white matter and gray substance. In this section there are visual hillocks, from where impulses pass to the cerebral cortex. Below them is the hypothalamus. The subcortical higher center is able to maintain the necessary environment inside the body.

The forebrain is presented in the form of cerebral hemispheres with a connecting part. The hemispheres are separated by a passage, under which there is a corpus callosum, connecting them with nerve processes. Under the cerebral cortex, which consists of neurons and processes, there is white matter, which acts as a conductor that unites the centers of the cerebral hemispheres together.

Functions

The work of the central nervous system, in short, consists of the following processes:

regulation of muscle movements of the ODS;
regulation of the functioning of the endocrine glands, which include the salivary, thyroid, pancreas and others;
the ability to realize smell, vision, touch, hearing, taste and maintain balance.

Thus, the functions of the central nervous system are the perception, analysis and synthesis of centripetal impulses that arise during stimulation of receptors located in tissues and organs.

The central nervous system ensures the adaptation of the human body to the environment.

The entire system must function as a single harmonious organism, since only due to this does an adequate reaction in response to stimuli from the surrounding world become possible.

The most common pathologies

Pathologies of the human central nervous system, its structure and functions can be provoked by various factors, from congenital diseases to infectious ones.

Conventionally, the following aspects may be the causes of central nervous system disorders:

Vascular pathologies are caused by the following factors:

problems in the blood vessels of the brain;
disruption of cerebral blood supply;
diseases of the cardiovascular system.

Vascular diseases include atherosclerosis, stroke and aneurysm. Such conditions are the most dangerous, as they often lead to death or disability. For example, a stroke leads to the death of nerve cells, making full recovery impossible. An aneurysm thins the walls of blood vessels, which can cause the vessel to burst, releasing blood into the surrounding tissue. This condition most often ends in death.

As for the psyche, even negative attitudes, thoughts and plans of a person have a negative impact on the functionality of the brain. If he feels unloved, offended, or experiences a constant feeling of envy, then his nervous system can suffer a serious malfunction, resulting in various diseases.

In infectious pathologies, the central nervous system is initially affected, followed by the PNS. These include the following conditions: meningitis, encephalitis, polio.

As for congenital pathologies, they can be caused by heredity, gene mutation or trauma during childbirth. The causes of this condition are the following processes: hypoxia, infection that occurred during pregnancy, injuries and medication taken during pregnancy.

Tumors can be localized in both the brain and spinal cord. Oncological diseases of the brain are more often registered in people aged twenty to fifty years.

Symptoms of diseases of the nervous system

In pathologies affecting the central nervous system, the clinical picture is divided into three symptomatic groups:

General signs.
Impaired motor functions.
Vegetative symptoms.

Nervous diseases are characterized by the following general symptoms:

Common symptoms also include psychosomatic disorders and sleep problems.

Diagnosis and treatment

To make a diagnosis, Doppler ultrasound and computed tomography may be required. Based on the results of the examination, the doctor prescribes appropriate treatment.

CNS - central nervous system- the main part of the nervous system of all animals, including humans, consisting of a collection of nerve cells (neurons) and their processes; in invertebrates it is represented by a system of closely interconnected nerve nodes (ganglia), in vertebrates - by the spinal cord and brain.

central nervous system(CNS), if considered in detail, consists of the forebrain, midbrain, hindbrain and spinal cord. In these main sections of the central nervous system, in turn, the most important structures are distinguished that are directly related to mental processes, states and properties of a person: the thalamus, hypothalamus, pons, cerebellum and medulla oblongata.

Main and specific function CNS- implementation of simple and complex highly differentiated reflective reactions, called reflexes. In higher animals and humans, the lower and middle sections of the central nervous system - the spinal cord, medulla oblongata, midbrain, diencephalon and cerebellum - regulate the activity of individual organs and systems of a highly developed organism, carry out communication and interaction between them, ensure the unity of the organism and the integrity of its activities. Higher department CNS- the cerebral cortex and the nearest subcortical formations - mainly regulates the connection and relationship of the body as a whole with the environment.
Almost all parts of the central and peripheral nervous system are involved in processing information coming through external and internal receptors located on the periphery of the body and in the organs themselves. The work of the cerebral cortex and subcortical structures included in the forebrain is associated with higher mental functions, with human thinking and consciousness.

The central nervous system is connected to all organs and tissues of the body through nerves emerging from the brain and spinal cord. They carry information entering the brain from the external environment and conduct it in the opposite direction to individual parts and organs of the body. Nerve fibers entering the brain from the periphery are called afferent, and those that conduct impulses from the center to the periphery are called efferent.
central nervous system represents clusters of nerve cells - neurons. CNS neurons form many circuits that perform two main functions: they provide reflex activity, as well as complex information processing in higher brain centers. These higher centers, such as the visual cortex (visual cortex), receive incoming information, process it, and transmit a response signal along the axons.
Tree-like processes extending from the bodies of nerve cells are called dendrites. One of these processes is elongated and connects the bodies of some neurons with the bodies or dendrites of other neurons. It's called an axon. Some axons are covered with a special myelin sheath, which facilitates faster impulse transmission along the nerve.
The places where nerve cells contact each other are called synapses. Through them, nerve impulses are transmitted from one cell to another. The mechanism of synaptic impulse transmission, operating on the basis of biochemical metabolic processes, can facilitate or hinder the passage of nerve impulses through the central nervous system and thereby participate in the regulation of many mental processes and states of the body.

CNS connected to all organs and tissues through the peripheral nervous system, which in vertebrates includes cranial nerves extending from the brain, and spinal nerves from the spinal cord, intervertebral nerve ganglia, as well as the peripheral part of the autonomic nervous system - nerve ganglia, with suitable to them (preganglionic) and nerve fibers extending from them (postganglionic). Sensitive, or afferent, nerve adductor fibers carry excitation to the central nervous system from peripheral receptors; along the efferent efferent (motor and autonomic) nerve fibers, excitation from the central nervous system is directed to the cells of the executive working apparatus (muscles, glands, blood vessels, etc.). In all departments CNS there are afferent neurons that perceive stimuli coming from the periphery, and efferent neurons that send nerve impulses to the periphery to various executive effector organs. Afferent and efferent cells with their processes can contact each other and form a two-neuron reflex arc that carries out elementary reflexes (for example, tendon reflexes of the spinal cord). But, as a rule, intercalary nerve cells, or interneurons, are located in the reflex arc between the afferent and efferent neurons. Communication between different parts of the central nervous system is also carried out using many processes of afferent, efferent and intercalary neurons of these parts, forming intracentral short and long pathways. Part CNS It also includes neuroglial cells, which perform a supporting function in it, and also participate in the metabolism of nerve cells.

NERVOUS SYSTEM, a very complex network of structures that permeates the entire body and ensures self-regulation of its vital functions due to the ability to respond to external and internal influences (stimuli). The main functions of the nervous system are receiving, storing and processing information from the external and internal environment, regulating and coordinating the activities of all organs and organ systems. In humans, as in mammals, the nervous system includes three main components: 1) nerve cells (neurons); 2) glial cells associated with them, in particular neuroglial cells, as well as cells forming neurilemma; 3) connective tissue. Neurons provide the conduction of nerve impulses; neuroglia performs supporting, protective and trophic functions both in the brain and in the spinal cord, and the neurilemma, consisting mainly of specialized, so-called. Schwann cells, participates in the formation of peripheral nerve fiber sheaths; Connective tissue supports and binds together the various parts of the nervous system.

The human nervous system is divided in different ways. Anatomically, it consists of the central nervous system ( CNS) and peripheral nervous system (PNS). CNS includes the brain and spinal cord, and the PNS, which provides communication between the central nervous system and various parts of the body, includes cranial and spinal nerves, as well as nerve ganglia and nerve plexuses lying outside the spinal cord and brain.
Neuron. The structural and functional unit of the nervous system is the nerve cell – neuron. It is estimated that there are more than 100 billion neurons in the human nervous system. A typical neuron consists of a body (i.e., the nuclear part) and processes, one usually non-branching process, an axon, and several branching ones - dendrites. The axon carries impulses from the cell body to muscles, glands or other neurons, while the dendrites carry them into the cell body.
A neuron, like other cells, has a nucleus and a number of tiny structures - organelles (see also

The main part of the nervous system of vertebrates and humans is the central nervous system. It is represented by the brain and spinal cord and consists of many clusters of neurons and their processes. The central nervous system performs many important functions, the main one of which is the implementation of various reflexes.

What is the CNS?

As we evolved, the regulation and coordination of all vital processes of the body began to occur at a completely new level. Improved mechanisms began to provide a very fast response to any changes in the external environment. In addition, they began to remember the effects on the body that occurred in the past and, if necessary, retrieve this information. Similar mechanisms formed the nervous system that appeared in humans and vertebrates. It is divided into central and peripheral.

So what is the CNS? This is the main department that not only unites, but also coordinates the work of all organs and systems, and also ensures continuous interaction with the external environment and maintains normal mental activity.

Structural unit

A similar path includes:

sensory receptor;
afferent, associative, efferent neurons;
effector

All reactions are divided into 2 types:

unconditional (innate);
conditional (acquired).

The nerve centers of a large number of reflexes are located in the central nervous system, but the reactions, as a rule, are closed outside its boundaries.

Coordination activities

This is the most important function of the central nervous system, implying the regulation of the processes of inhibition and excitation in the structures of neurons, as well as the implementation of responses.

Coordination is necessary for the body to perform complex movements that involve numerous muscles. Examples: performing gymnastic exercises; speech accompanied by articulation; the process of swallowing food.

Pathologies

It is worth noting that the central nervous system is a system whose dysfunction negatively affects the functioning of the entire organism. Any failure poses a health hazard. Therefore, when the first alarming symptoms appear, you should consult a doctor.

The main types of central nervous system diseases are:

vascular;
chronic;
hereditary;
infectious;
received as a result of injuries.

Currently, about 30 pathologies of this system are known. The most common diseases of the central nervous system include:

Pathologies of the central nervous system arise as a result of lesions in any of its departments. Each of the ailments has unique symptoms and requires an individual approach to choosing a treatment method.

Finally

The task of the central nervous system is to ensure the coordinated functioning of each cell of the body, as well as its interaction with the outside world. Brief description of the central nervous system: it is represented by the brain and spinal cord, its structural unit is the neuron, and the main principle of its activity is reflex. Any disturbances in the functioning of the central nervous system inevitably lead to disruptions in the functioning of the entire body.

They regulate the activities of individual organs and systems of a highly developed organism, carry out communication and interaction between them, ensure the unity of the organism and the integrity of its activities. The higher department of the central nervous system - the cerebral cortex and the nearest subcortical formations - mainly regulates the connection and relationship of the body as a whole with the environment.

Main structural features and functions

The central nervous system is connected to all organs and tissues through the peripheral nervous system, which in vertebrates includes cranial nerves extending from the brain and spinal nerves from the spinal cord, intervertebral nerve ganglia, as well as the peripheral part of the autonomic nervous system - nerve ganglia , from ancient Greek. γανγλιον ), with nerve fibers approaching them (preganglionic) and extending from them (postganglionic). Sensitive, or afferent, nerve adductor fibers carry excitation to the central nervous system from peripheral receptors; along the efferent efferent (motor and autonomic) nerve fibers, excitation from the central nervous system is directed to the cells of the executive working apparatus (muscles, glands, blood vessels, etc.). In all parts of the central nervous system there are afferent neurons that perceive stimuli coming from the periphery, and efferent neurons that send nerve impulses to the periphery to various executive effector organs. Afferent and efferent cells with their processes can contact each other and form a two-neuron reflex arc that carries out elementary reflexes (for example, tendon reflexes of the spinal cord). But, as a rule, intercalary nerve cells, or interneurons, are located in the reflex arc between the afferent and efferent neurons. Communication between different parts of the central nervous system is also carried out using many processes of afferent, efferent and intercalary neurons of these parts, forming intracentral short and long pathways. The CNS also includes neuroglial cells, which perform a supporting function in it and also participate in the metabolism of nerve cells. The brain and spinal cord are covered by three meninges: dura mater, arachnoid and choroid and are enclosed in a protective capsule consisting of the skull and spine.

Hard - external, connective and swallowing, lining the internal cavity of the skull and spinal canal. The arachnoid is located under the dura mater - it is a thin shell with a small number of nerves and vessels. The choroid is fused with the brain, extends into the grooves and contains many blood vessels.

The spinal cord is located in the spinal canal and has the appearance of a white cord. Longitudinal grooves are located along the anterior and posterior surfaces of the spinal cord. The spinal canal runs in the center, with gray matter concentrated around it - an accumulation of a huge number of nerve cells that form a butterfly outline.

The white matter of the spinal cord forms pathways that stretch along the spinal cord, connecting both its individual segments with each other and the spinal cord with the brain. Some pathways are called ascending or sensory, transmitting excitation to the brain, others are called descending or motor, which conduct impulses from the brain to certain segments of the spinal cord. They perform two functions - reflex and conductive. The activity of the spinal cord is controlled by the brain, which regulates spinal reflexes.

The human brain is located in the medulla of the skull. Its average weight is 1300-1400 g. Brain growth continues up to 20 years. It consists of 5 sections: the forebrain, intermediate, middle, hindbrain and medulla oblongata. Inside the brain there are 4 interconnected cavities - the cerebral ventricles. They are filled with cerebrospinal fluid. The phylogenetically more ancient part is the brain stem. The trunk includes the medulla oblongata, pons, midbrain and diencephalon. 12 pairs of cranial nerves lie in the brain stem. The brainstem is covered by the cerebral hemispheres.

The medulla oblongata is a continuation of the spinal cord and repeats its structure; There are grooves on the anterior and posterior surfaces. It consists of white matter, where clusters of gray matter are scattered - the nuclei from which cranial nerves originate - from the 9th to the 12th pair.

The hindbrain includes the pons and cerebellum. The pons is bounded below by the medulla oblongata, passes into the cerebral peduncles above, and its lateral sections form the middle cerebellar peduncles. The cerebellum is located behind the pons and medulla oblongata. Its surface consists of gray matter (cortex). Under the bark are the kernels.

The midbrain is located in front of the pons and is represented by the quadrigeminal cord and cerebral peduncles. The diencephalon occupies the highest position and lies in front of the cerebral peduncles. Consists of the visual tuberosities, supracubertal, subtubercular region and geniculate bodies. At the periphery of the diencephalon there is white matter. The forebrain consists of highly developed hemispheres and the middle part connecting them. The grooves divide the surface of the hemispheres into lobes; In each hemisphere there are 4 lobes: frontal, parietal, temporal and occipital.

The activity of analyzers reflects the external material world in our consciousness. The activity of the cerebral cortex of humans and higher animals was defined by I. P. Pavlov as higher nervous activity, which is a conditioned reflex function of the cerebral cortex.

Nervous system
Normal human anatomy
Central	Brain \| Brain structures \| Spinal cord
Peripheral	Somatic nervous system Autonomic nervous system: Sympathetic nervous system \| Parasympathetic Nervous System \| Enteric nervous system

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See what “Central nervous system” is in other dictionaries:

central nervous system- Nervous tissue, like all other tissues of the body, consists of an infinite number of cells with a special form and function. Cells that are highly differentiated are called nerve cells or neurons. The nervous system controls the functioning of... ... Universal additional practical explanatory dictionary by I. Mostitsky

central nervous system- consists of the brain and spinal cord. Spinal cord Brain Pathways of the nervous system Meninges and interthecal spaces * * * See also ... Atlas of Human Anatomy

central nervous system- (CNS central nervous system) consists of nervous tissue of the brain and spinal cord, the main elements of which are nerve cells, neurons and glial cells. The latter ensure the preservation of the constancy of the internal environment of the system... ... Great psychological encyclopedia

The main part of the nervous system of animals and humans, consisting of nerve cells (neurons) and their processes. It is represented in invertebrate animals by a system of nerve nodes (ganglia) connected to each other, in vertebrate animals and humans... ... Big Encyclopedic Dictionary

- (CNS), in some higher invertebrates there is a nerve canal along the length of which there are bundles of NEURONS called GANGLIA. They control actions such as the movement of limbs, wings, etc. In vertebrates, part of the NERVOUS SYSTEM that... ... Scientific and technical encyclopedic dictionary

- (systema nervosum centrale), central nervous system, the main part of the nervous system of animals and humans, represented in invertebrates by ganglia and the nerve cord, in vertebrates by the spinal cord and brain. Home and specific for the central nervous system activity implementation... ... Biological encyclopedic dictionary

Noun, number of synonyms: 1 tsns (1) Dictionary of synonyms ASIS. V.N. Trishin. 2013… Synonym dictionary

Occurs for the first time in some intestinal cavities. Sponges appear to be completely devoid of a nervous system. In hydroids, the nervous system is represented by ganglion cells scattered in the ectoderm, which are a modification of the sensory... ... Encyclopedic Dictionary F.A. Brockhaus and I.A. Efron

central nervous system- centrinė nervų sistema statusas T sritis švietimas apibrėžtis Žmogaus arba stuburinių gyvūnų galvos ir stuburo smegenų sandara, vienijanti visų organų veiklą ir reguliuojanti organizmo ryšius su išoriniu pasauliu . Tai fiziologinis išmokimo… … Enciklopedinis edukologijos žodynas

Books

Central nervous system. Workbook for the textbook (in English), Gaivoronsky Ivan Vasilievich, Nichiporuk Gennady Ivanovich, Kurtseva Anna Andreevna, Gaivoronskaya Maria Georgievna. This manual is the English version of the textbook by Professor I.V. Gaivoronsky “Normal Human Anatomy”, which was published in Russia 9 times and approved by the Ministry of Education...

CNS - what is it? The structure of the human nervous system is described as an extensive electrical network. Perhaps this is the most accurate metaphor possible, since current actually runs through thin filament threads. Our cells themselves generate microdischarges in order to quickly deliver information from receptors and sensory organs to the brain. But the system does not function randomly; everything is subject to a strict hierarchy. That is why they highlight

Departments of the central nervous system

Let's take a closer look at this system. And yet, what is the central nervous system? Medicine provides a comprehensive answer to this question. This is the main part of the nervous system of chordates and humans. It consists of structural units - neurons. In invertebrates, this entire structure looks like a cluster of nodules that have no clear subordination to each other.

The human central nervous system is represented by a ligament of the brain and spinal cord. In the latter, the cervical, thoracic, lumbar and sacrococcygeal regions are distinguished. They are located in the corresponding parts of the body. Almost all peripheral nerve impulses are carried to the spinal cord.

The brain is also divided into several parts, each of which has a specific function, but their work is coordinated by the neocortex, or cerebral cortex. So, anatomically they distinguish:

brain stem;
medulla;
hindbrain (pons and cerebellum);
midbrain (lamina quadrigeminalis and cerebral peduncles);
forebrain

Each of these parts will be discussed in more detail below. This structure of the nervous system was formed in the process of human evolution so that he could ensure his existence in new living conditions.

Spinal cord

It is one of two organs of the central nervous system. The physiology of its work is no different from that in the brain: with the help of complex chemical compounds (neurotransmitters) and the laws of physics (in particular, electricity), information from small branches of nerves is combined into large trunks and either implemented in the form of reflexes in the corresponding part of the spinal cord, or enters the brain for further processing.

Located in the hole between the arches and vertebral bodies. It is protected, like the head membrane, by three membranes: hard, arachnoid and soft. The space between these tissue sheets is filled with fluid, which nourishes the nervous tissue and also acts as a shock absorber (dampens vibrations during movements). The spinal cord begins from the opening in the occipital bone, at the border with the medulla oblongata, and ends at the level of the first and second lumbar vertebrae. Next are only the membranes, cerebrospinal fluid and long nerve fibers (“cauda equina”). Conventionally, anatomists divide it into departments and segments.

On the sides of each segment (corresponding to the height of the vertebra) sensory and motor nerve fibers called roots extend. These are long processes of neurons, the bodies of which are located directly in the spinal cord. They are a collector of information from other parts of the body.

Medulla

The medulla oblongata is also involved in activities. It is part of a formation such as the brain stem and is in direct contact with the spinal cord. There is a conventional boundary between these anatomical formations - this is the decussation. It is separated from the bridge by a transverse groove and a section of the auditory tract that runs in the rhomboid fossa.

In the thickness of the medulla oblongata there are nuclei of the 9th, 10th, 11th and 12th cranial nerves, fibers of the ascending and descending nerve tracts and the reticular formation. This area is responsible for performing protective reflexes such as sneezing, coughing, vomiting and others. It also keeps us alive by regulating breathing and heartbeat. In addition, the medulla oblongata contains centers for regulating muscle tone and maintaining posture.

Bridge

Together with the cerebellum, it is the posterior part of the central nervous system. What is this? A collection of neurons and their processes located between the transverse sulcus and the exit point of the fourth pair of cranial nerves. It is a roller-shaped thickening with a depression in the center (it contains blood vessels). The fibers of the trigeminal nerve emerge from the middle of the bridge. In addition, the superior and middle cerebellar peduncles extend from the pons, and in the upper part of the pons are the nuclei of the 8th, 7th, 6th and 5th pairs of cranial nerves, a section of the auditory tract and the reticular formation.

The main function of the bridge is to transmit information to the higher and lower parts of the central nervous system. Many ascending and descending pathways pass through it, which end or begin their path in different parts of the cerebral cortex.

Cerebellum

This is the department of the central nervous system (CNS), which is responsible for coordinating movements, maintaining balance and maintaining muscle tone. It is located between the pons and the midbrain. To obtain information about the environment, it has three pairs of legs through which nerve fibers pass.

The cerebellum acts as an intermediate collector of all information. It receives signals from sensory fibers of the spinal cord, as well as from motor fibers starting in the cortex. After analyzing the data obtained, the cerebellum sends impulses to the motor centers and corrects the position of the body in space. All this happens so quickly and smoothly that we do not notice its work. All our dynamic automatisms (dancing, playing musical instruments, writing) are the responsibility of the cerebellum.

Midbrain

There is a department in the human central nervous system that is responsible for visual perception. This is the midbrain. It consists of two parts:

The lower one represents the legs of the brain, in which the pyramidal tracts pass.
The upper one is the quadrigeminal plate, on which, in fact, the visual and auditory centers are located.

The formations in the upper part are closely connected with the diencephalon, so there is not even an anatomical border between them. Conventionally, we can assume that this is the posterior commissure of the cerebral hemispheres. In the depths of the midbrain there are the nuclei of the third cranial nerve - the oculomotor nerve, and in addition to this there is also the red nucleus (it is responsible for controlling movements), the substantia nigra (initiates movements) and the reticular formation.

The main functions of this area of the central nervous system:

orientation reflexes (reaction to strong stimuli: light, sound, pain, etc.);
vision;
pupil reaction to light and accommodation;
friendly turn of the head and eyes;
maintaining skeletal muscle tone.

Diencephalon

This formation is located above the midbrain, just below the corpus callosum. It consists of the thalamic part, the hypothalamus and the third ventricle. The thalamic part includes the thalamus itself (or thalamus), epithalamus and metathalamus.

The thalamus is the center of all types of sensitivity; it collects all afferent impulses and redistributes them into the appropriate motor pathways.
The epithalamus (epiphysis, or pineal body) is an endocrine gland. Its main function is the regulation of human biorhythms.
The metathalamus is formed by the medial and lateral geniculate bodies. The medial bodies represent the subcortical center of hearing, and the lateral bodies represent the center of vision.

The hypothalamus controls the pituitary gland and other endocrine glands. In addition, it partially regulates the autonomic nervous system. We have to thank him for the speed of metabolism and maintaining body temperature. The third ventricle is a narrow cavity that contains the fluid necessary to nourish the central nervous system.

Cortex of the hemispheres

Neocortex CNS - what is it? This is the youngest section of the nervous system, phylo - and ontogenetically it is one of the last to be formed and consists of rows of cells densely layered on top of each other. This area occupies about half of the total space of the cerebral hemispheres. It contains convolutions and grooves.

There are five parts of the cortex: frontal, parietal, temporal, occipital and insular. Each of them is responsible for their own area of work. For example, the frontal lobe contains the centers of movement and emotion. In the parietal and temporal are the centers of writing, speech, small and complex movements, in the occipital are visual and auditory, and the insular lobe corresponds to balance and coordination.

All information that is perceived by the endings of the peripheral nervous system, be it smell, taste, temperature, pressure or anything else, enters the cerebral cortex and is carefully processed. This process is so automated that when it is stopped or disrupted due to pathological changes, the person becomes disabled.

Functions of the central nervous system

For such a complex formation as the central nervous system, its corresponding functions are also characteristic. The first of them is integrative-coordination. It implies the coordinated work of various organs and systems of the body to maintain a constant internal environment. The next function is the connection between a person and his environment, the body’s adequate reactions to physical, chemical or biological stimuli. In addition, this includes social activities.

The functions of the central nervous system also cover metabolic processes, their speed, quality and quantity. For this purpose, there are separate structures, such as the hypothalamus and pituitary gland. Higher mental activity is also possible only thanks to the central nervous system. When the cortex dies, the so-called “social death” is observed, when the human body still retains vitality, but as a member of society he no longer exists (he cannot speak, read, write and perceive other information, as well as reproduce it).

It is difficult to imagine humans and other animals without the central nervous system. Its physiology is complex and not yet fully understood. Scientists are trying to understand how the most complex biological computer ever existed works. But this is like “a bunch of atoms studying other atoms,” so progress in this area is not yet sufficient.