Man eats, breathes, moves and carries many other functions thanks to (CNS). It consists mainly of neurons (nerve cells) and their processes (axons), for which all signals pass. It is impossible not to mark Gliya, which is auxiliary nervous fiber. Thanks to this tissue in neurons, the generation of pulses going in the head and spinal cord occurs. It is these 2 authorities that are the basis of the CNS and manage all processes in the body.

A special role is played by the spinal cord of a person and to understand where it can be located, looking at the cross section of the spine, since it is located in it. Focusing on the structure of this body, it can be understood for which it is responsible and how the relationship with most of the human systems is carried out.

The spinal cord is predominantly from the spider shell, as well as from soft and solid components. Protects the body from the damage to the fat layer localized directly under the bone tissue in the epidural space.

Most people know where the spinal cord is located, but few understand its anatomical features. This organ can be represented as thick (1 cm) the wires of the long actual half the meter, which is localized in the spine. Capacious spinal cord It is a spinal channel consisting of vertebrae, at the expense of which it is protected from external influence.

The organ from the occipital opening begins, and ends at the level of the loin where it is represented as a cone consisting of connective tissue. It resembles a thread in shape and comes straight to the tailbone (2 vertebra). You can see the spinal cord segments in this picture:

Channels come out the roots of the spinal nerves, which serve to carry out the movements of the hands and legs. From above and in the center they have 2 thickening at the level of the neck and lower back. At the bottom of the spinal cord root resemble a tangle formed around the spinal threads.

The transverse cut of the spinal cord is as follows:

The anatomy of the spinal cord is designed to answer many questions related to the work of this body. Judging by the system of rear of the organ of localized the groove of the spinal nerve, and the special hole is located in front. It is through it that nervous rootscarrying innervation of certain systems of the body.

Internal structure The spinal cord segment tells many details of his work. It consists of an organ mainly from the white (aggregate axon) and a gray (combination of neurons) substances. They are the beginning of many nerve paths and such segments of the spinal cord are mainly responsible for the reflexes and the transmission of signals in the brain.

The functions of the spinal cord are diverse and depend on the level of which level are nerves. For an example of white substance, nervous pathways of the front valves of the central nervous system are coming. The rear of the fibers is indicators of sensitivity. Of these, the segment of the spinal cord is formed, in which the spinal roots on both sides are collected. The main object of the white substance is the transfer of the obtained pulses in the brain for further processing.

The structure of the spinal cord of a person is not so complicated as it seems. The main thing is to remember that the spine includes 31 segments. All of them differ in size and divided into 5 departments. Each of them performs certain features of the spinal cord.

White substance

The spinal channel is the place of cluster of the white substance. It is 3 core surrounding the gray substance, and consists mainly of axons covered with myelin shell. Thanks to myelina, the signal is moving faster on them, and the substance receives its shade.

The white substance is responsible for the innervation of the lower extremities and shipping the pulses in the brain. Seeing his codes, as well as a horn of gray matter in this picture:

Gray matter

Most people do not understand what the gray substance looks like and why he has such a form, but in fact everything is quite simple. Due to the accumulation of nerve cells (motor and inserted neurons) and actually the complete absence of axons it has gray. Localized gray substance in a spinal channel and many it seems that this is a butterfly due to pillars and plates in the center.

The gray substance corresponds primarily for motor reflexes.

In his center there is a channel, which is a container of a liquid, which is a cerebrospinal fluid. Its function includes protection against damage and support for permissible pressure inside the cranial box.

The main amount of gray substance falls on the front horns. They consist mainly of motor nerve cells that perform innervation of muscle tissues at the level of this segment. Fewer substance gets back horns. They include mainly inserting neurons that serve to communicate with other nerve cells.

If you look at the spinal channel in the cut, then the intermediate zone is striking, localized in space between the front and rear horns. There is this area only at 8 vertebra cervical region And goes up to 2 segments of the lower back. In this area, side horns begin, which are accumulated by nerve cells.

The role of conductive paths

Conducting ways serve to communicate the spinal and brain and take their origin in the rear wire of a white substance. They are divided into 2 types:

• Rising paths (transmitting signal);
• Downlink paths (receiving signal).

To place complete information about them anatomical features It is necessary to take a look at this drawing:

A signal is transmitted through certain beams, for example, the upper part of the body in the spinal cord represents a wedge-shaped plexus, and the lower thin. To see next to which these fibers are located in this picture:

A special role in the conductive system is performed by a renovative path. It begins from skeletal muscles and ends directly in the clogenet itself. Separate attention should be paid to the Talalamic path. He is responsible for the perception of pain and the temperature of the person. Talamus receives a signal from the front of the ceremony path, which consists mainly of inserted neurons.

Functions

A person has always had many questions regarding their body, because it is difficult to understand how all the systems are connected with each other. The spinal cord has a structure and functions are interrelated, so terrible consequences arise with any pathological changes. It is virtually impossible to eliminate them, so you need to take your spine.

Responses the spinal cord for the following functions:

• Conductive. Its essence is the transmission of the signal to certain parts of the body depending on the localization of the nervous beam. If it comes to the upper half of the body, then the cervical department is responsible for it, for the resignation organs, and the sacratsone innervates the pelvis and lower limbs.
• Reflex. Such a function is performed without the participation of the brain, for example, if you touch the hot iron, the limb moves involuntarily.

Fixed spinal cosk

Many different pathologies are associated with the spinal cord, whose treatment is performed mainly in the hospital. Such diseases refers to a fixed spinal cord syndrome. This pathological process is diagnosed with extremely rarely and peculiar to the disease both children and adult people. For pathology, the fixation of the spinal cord to the spinal column is characteristic. Most often there is a problem in the lumbar department.

Fixed spinal cords are usually found in the diagnostic center with tool methods Surveys (MRI), and it arises due to such reasons:

• Neoplasms, squeezing spinal cord;
• Arising scar tissue after surgery;
• Severe injury in the field of the belt;
• Plok Kiari.

Usually, the fixed spinal cord syndrome in patients is manifested in the form of neurological symptoms and the main manifestations relate to legs and areas of damage. A person is deformed by the lower limbs, it becomes difficult to walk and failures in the work of the pelvic organs appear.

The disease occurs at any age and its course is usually consisting of an operation and a long period of recovery. Basically, after surgery, the defect is obtained and partially relieve the patient from the effects of pathology. Because of what people begin to actually walk and stop experiencing pain.

There is another pathology that some experts are associated with a spinal cord, namely hemispasm (hemifacial spasm). It is a disturbance of the facial nerve due to the reduction of muscle tissue, which is on the face. The disease occurs without pain and such spasms are called clonic. They arise due to the squeezing of the nervous tissue in the area of \u200b\u200bits exit from the brain. The diagnosis of the pathological process is carried out using MRI and electromyography. According to statistics, each year, hemicacial spasm can be diagnosed in 1 of 120,000 people and the female floor suffers from it 2 times more often.

Basically, the squeezing of the facial nerve occurs due to vessels or neoplasms, but sometimes hemispanse arises due to such reasons:

• Process of demyelination;
• Spikes;
• Bone anomalies;
• Tumors located in the brain.

Hemifacial spasm can be eliminated with medication therapy. For the treatment of facial nerve, a bitplopen, levatracy, gabapentin, carbamazepine, etc., will have to take them quite a long time, so such a course has its own minuses:

• Over time, the effect of drugs begins to end and faster and for the treatment of facial nerve will have to change drugs or increase the dosage;
• Many listed drugs have a sedative effect, therefore people who are diagnosed with hemispanis are often in sleepy state.

Despite the minuses, many cases were recorded full cure Facial nerve and removal of hemispasza. Drug therapy for the early stages of the development of pathology was particularly well influenced.

Eliminate hemicacial spasm can also be used toxin injecting botulin. It effectively eliminates the problem at any stage. Of the minuses of the procedure, you can note the high cost and contraindications in which allergic reactions The composition of the drug and eye disease.

The most efficient and rapid treatment of hemispanis is surgery. It is carried out with the aim of eliminating compression and, in the case of a patient's successfully conducted operation, written after a week. The full effect of recovery is achieved quite quickly, but in some cases it is stretched to six months.

The spinal cord is an important center nervous system And any deviations in its structure may affect the entire body. That is why, in the manifestation of neurological symptoms, contact a neurologist for the passage of examination and diagnosis.

From how the central nervous system is functioning, the work of all organs, as well as the overall health of a person depends. A big role is played by the spinal cord. It is located in such a way that is in relationship with each cell of the body. All motor reflexes are caused by its actions. This body transmits signals to the brain of the head - to the "Central Staff", which carries out opposite communication with the authorities.

What does the spinal cord look like

Structure of the brain

A man's spinal cord, something similar to an electrical cable, fills the spine channel. At the same time, inside this body of two halves, distributed among themselves the obligations of the right and left sides of the body.

Brain formation occurs on the most early stage Embryo development. It is he who is the basis for which all other elements of the embryo are increasing. Starting to develop at the end of the first month after conception, the spinal cord is differentiated throughout the pregnancy. At the same time, part of the departments undergoes the subsequent revision of the first childhood.

The whole spinal cord laid in the canal is biting a triple shell. In this case, the inner of them is sufficiently soft, consisting of vessels, outdoor - solid to ensure the protection of tissues. Between them is another "braid" - web. The space between this shell and the inner contains a liquid that provides elasticity. The inner space is filled with a gray shade substance, whipped white substance.

Cross-cut brain

If we consider the structure of the spinal cord in cross-section, then the structural shape of a gray substance is clearly distinguished in the section, resembling a small butterfly, laid down on a penet. Each of the part of the structure has certain features that are described below.

To the substance with gray "connected" the roots of the nerves, which, passing through the white substance, are assembled into nodes that determine the structure of the nerve of the spinal out. Bundles of nerve fibers are conductive ways that provide the links of the Central Staff with specific authorities. The spinal cord includes from 31 to 33 pairs of vertebrae formed in segments.

Cone brain

The vertebral channel is directly conjugate with the brain placed in the head, and the bottom line begins at the bottom line. In constant form, the channel passes up to the vertebrae of the lumbar and ends with a cone, which has a continuation of the terminal thread, the upper part contains the fibers of the nerves.

The cone in its structure is represented by a three-layer coupling cloth. On the vertebral in the area of \u200b\u200bthe tailbone, where he processed with the periosteum, and ends the thread indicated above. Here is the so-called "horse tail" - a bundle of the lower nerves, whining the thread.

What is the nervous system

The main assembly of nervous fibers is in 2 places - the sacroist-lumbar department and in the neck area. It is pronounced by peculiar seals responsible for the function of the limbs.

The brain spins, filling the spinal channel, has a strictly fixed position and unchanged parameters. Its length in an adult is about 41-45 cm, with this weight has no more than 38 g.

Gray substance

So, the brainstant on the cross section looks like a moth, and is inside a white tonality substance. The center for the entire length of the brain of the dorsal is the narrow channel, which is called the central one. This channel fills the liquid - a variety of liquid by the spinal surgery responsible for the operation of the system nervous.

Gray "Moth"

The brain and central dorsal canal are among themselves in relationships. Also are also compatible with spaces placed between the brain shells - they circulate the liquid of the spinal volume. It is her by means of puncture, they take research when a number of problems affect the spinal cord departments are diagnosed.

The gray substance is the similarity of pillars connected in cross-performance by plates. Spacks total 2: The back and front part constituting the central cerebral channel. They form a butterfly (Literature H).

In the sides of the substance, the horns are dismissed. Paired wide fill the front part, narrow - rear:

• In the front there are neurons of movement. Their processes (neurites) are formed in the spinal cord roots. The neurons are also created and the core of the brain of the dorsal, which in stock 5.
• The horn of the rear in the middle there is its own nucleus from neurons neurons. Each process (Akson) is located in the direction of the front horns crossing the spike. At the rear horn, an additional core has been formed from large neurons, which has the branching of dendrins in its structure.
• Between the main horns there is still an intermediate brain part. Here you can observe the branch of the horns of the side. But it does not appear on all segments, but only from the 6th cervical and to the 2nd lumbar. Nerves cells here create a lateral substance, which is responsible for the veguetative system.

White substance

Enveloping a gray substance The substance of a white shade is a set of 3 pairs of cakes. Between the furrows located the roots of the front rope. There are also rear and side, each of which is located between specific grooves.

Fibers forming a light substance pass through themselves signals emanating from nerves. Some are directed through the channel in the brain, others - in the dorsal and below the lying departments. Intersome relations are carried out by the fibers of a gray substance.

The roots of the spinal cord, located behind, are the fibers of the neurons of the ganglia of the spinal. The part is located in the horn of the rear, the rest diverge in different directions. A group of fibers included in the core is directed to the brain of the head - it is the ways of ascending type. Part of the fibers is in the back horns on the neurons of inserts, the rest goes to the Divines of the National Assembly.

Various paths

Above it has already been said that the brain receives signals emanating from neurons. On the same paths and in the opposite direction there is a movement of signals. A bundle of wedge-shaped neurons sends signals from endings located on the joints and muscles to the brain oblong.

The entire spinal cord filling the vertebral channel performs functions by bundles sending signals to the upper and lower part of the body. Each pulse group begins from the "its" site and moves according to their paths.

So, the core medial intermediate gives the beginning for the forefront. On the opposite side of the horns there is a path that is responsible for painful and thermal sensations. The signals are pre-entered into the brain intermediate, and then in the head.

Functional features

After examining the structure of the spinal cord, it is easy to conclude that this is a rather complicated system, "mounted" to the vertebral channel, and in the technical plan resembling an intricate circuit of an electronic device. In the perfect version, it should work safely and uninterrupted, performing certain functions programmed by nature.

System structure

From the described structure of the brain, it can be seen that it has 2 main responsibilities: to be conductor of impulses and provide motor reflexes:

• Under reflexes, they mean the ability to involuntarily pull the hand at risk randomly damage it with a hammer in the process of clogging the nails, or a sharp jump aside from the mouse running past. The reflex arc is caused by such actions that binds the muscles of the skeleton with the brain of the spinal. And it takes on the corresponding nerve impulses. At the same time there are reflexes congenital (laid by nature at the Gennel) and acquired, which developed in a vital process.
• The function of the conductor includes a pulse transmission on the rising paths from the scorn to the brain and in the reverse order - by descending. These pulses of the spinal cord distributes for all human bodies (according to the program). For example, the sensitivity of the fingers is developed precisely thanks to the conductor function - a person is adopted to the kitten, and the signal appears in the headquarters that form certain associations there.

The channel, which is performed by the functions of the motor, the beginning of its origin in the red core, turning gradually to the horns of the front. Here is a set of motion cells. Reflex impulses are transmitted on the front tracks, arbitrary - in lateral. The path to the brain is the front of the vestibular kernels ensures the execution of the equilibrium function.

Vascular system

The work of the brain is not possible without a normal blood supply, which is one for the whole organism. The spinal cord is constantly washed by blood passing by arteries - spinal and root-spinal. The number of such vessels is individually, because Sometimes additional arteries are observed in a number of people.

How does the blood supply for the brain

The rear roots (and therefore vessels) are always greater, but their arteries are less in diameter. Each vessel is washes his blood supply zone. But present in the system and the connection of the vessels between themselves (anastomosis), which ensures sufficient food for the brain of the dorsal.

Anastomosis is a spare channel used when functions are knocked out at the main vessel (for example, clogging thrombus). Then the spare element assumes the duty of blood transportation, immediately after the process.

Vessel plexes are formed in the shell. So each root of the nerve system is accompanied by veins and arteries that form a neuro-vascular bundle. It is his damage that leads to various pathologies manifested by pain symptoms.

To identify such a violation, you will have to go through a number of different diagnostic studies.

Each artery is accompanied by hollow veins, in which blood flows out of the spinal cord. So that the fluid has not returned back, on solid brain sheath A set of special enclosing valves is located, which determine the correct direction of movement of the circulatory "river".

Video. Spinal cord

Without the normal reliable operation of such an important organ as a spinal cord, it is impossible not only to move, but also breathe. Any activity (digestion, measurement and urination, heartbeat, libido, etc.) is unthinkable without his participation, because Brain functions are fully guided by all these actions.

It is they who warn a person from various bruises and injuries, because Impulses carry information not only about touch, odors, movements, but also orient the body in space, and also help respond to danger. Therefore, it is so important to maintain the performance of an important component pushed into the spinal channel.

Lecture 2. Nervous System

Building and function

Structure. It is anatomically divided into central and peripheral, the central nervous system includes a head and spinal cord, to the peripheral - 12 pairs of cunning nerves and 31 pair of cerebrospinal nerves and nerve nodes. A functionally nervous system can be divided into somatic and autonomous (vegetative). The somatic part of the nervous system regulates the operation of skeletal muscles, autonomous controls the operation of the internal organs.

Nerves can be sensitive (visual, olfactory, auditory), if they are excited to the central nervous system, motor (ooo), if the excitement goes from the central nervous system and mixed (wandering, spinal surge), if the excitation of one fibers goes into one -, and in others - in the other direction.

Functions. The nervous system regulates the activities of all organs and systems of organs, communicates with the external environment with the help of the senses, and is also the material basis for higher nervous activities, thinking, behavior and speech.

The structure and function of the spinal cord

Structure. The spinal cord is located in the spine from the first cervical vertebra to I - II lumbar, the length is about 45 cm, the thickness is about 1 cm. The front and rear longitudinal furrows divide it into two symmetric halves. The center passes the spinal channel in which spinal fluid. In the middle of the spinal cord, the gray substance is located near the spinal channel, on the cross cut resembling the contour of the butterfly. The gray substance is formed by the bodies of neurons, it distinguishes the front and rear horns. In the rear horns of the spinal cord are the bodies of inserts of neurons, in the front of the body of motor neurons. In the chest department there are also lateral horns, in which neurons of the sympathetic part of the autonomous nervous system are located. Around the gray substance is a white substance formed by nerve fibers. The spinal cord is covered with three shells: outside the connecting and tight is dense, then the web and the vascular one.

31 pair of mixed cerebral nerves are departed from the spinal cord. Each nerve begins with two roots, front (motor), in which there are processes of motor neurons and vegetative fibers, and rear (sensitive), according to which the excitation is transmitted to the spinal cord. In the rear roots there are spinal assemblies, accumulation of sensitive neurons.

The rear of the rear roots leads to the loss of sensitivity in those areas that are innervated by the corresponding roots, the cut of the front roots leads to paralysis of the innervated muscles.

The spinal cord, Medulla Spinalis lies in the spinal Channel and in adults is a long (45cm in men and 41-42cm in women), a somewhat flattened in front of the cylindrical litter, which is at the top (cranial) goes directly into the oblongable brain, and below (caudally) ends with a conical aconution, Conus Medullaris, at the level II of the lumbar vertebra

The spinal cord at its length has 2 thickens corresponding to the roots of the nerves of the upper and lower extremities: the top of them is called cervical thickening, Intumescentia Cervicalis, A Lower - lumbar-sacral, Intumescentia Lumbosacralis. From these thickens is more pronounced lumbosacral, but the cervical is more differentiated, which is associated with a more complex arm innervation as an organ of labor. Formed as a result of the thickening of the side walls of the spinal tube and passing along the middle line of the front and rear longitudinal furrows: deep Fissiira Mediana Anterior and the surface Siilcus Medianus Posterior - the spinal cord is divided into 2 symmetric half - right and left; Each of them, in turn, has a weakly pronounced longitudinal furrow, running along the entry line of the rear roots (Siilcus Posterolateralis) and along the front of the front root (Siilcus ANTEROLATERIS).

These furrows divide each half of the spinal cord white on 3 longitudinal cords: front, funiculus anterior, side, funiculus lateralis, and rear, funiculus posterior. The rear rope in the cervical and uppergrochny departments is still an intermediate groove, Sulcus Intermedius Posterior, 2 beam: Fasciculus Gracilis and FasciCULUS CUNEATUS. Both of these beams under the same names are moving at the top of the rear side of the oblong brain. On the other side of the spinal cord there are two longitudinal rows of spinal nerves roots. Front root, Radix Ventralis s. Anterior, leaving the Siilcus ANTEROLATERIS, consists of neurites of motor (centrifugal, or efferent) neurons whose cellular bodies lie in the spinal cord, while the rear root, Radix Dorsalis s. RosteriR, which is part of Siilcus Posterolateralis, contains sensitive processes (centripetal, or afferent) neurons whose bodies lie in the spinal nodes.

5.2 The internal structure of the spinal cord

The spinal curt consists of a gray substance containing nervous cells, and a white substance, composed of myeline nerve fibers.

A. Gray substance, Substantia grisea is laid inside the spinal cord and is surrounded by white substance from all sides. The gray substance forms 2 vertical columns placed in the right and left half of the spinal cord. In the middle there is a narrow central channel, Canalis Centralis, spinal cord, passing through the entire length of the latter and containing the cerebrospinal fluid. The central channel is the residue of the primary nervous tube cavity. Therefore, it is reported to the IV ventricle of the brain, and in the Conus Medullaris area ends with an expansion - end ventricular, Ventriculus Terminalis.

Gray substance surrounding central channel, is called intermediate, SUBSTANTIA INTERMEDIA CENTRALIS. In each column of the gray substance there are 2 posts: front, Coliimna Anterior, and rear, Coliimna Posterior.

On transverse cuts of the spinal cord, these pillars have the kind of horns: front, extended, Cornu Anterius, and rear, pointed, Cornu Rosterius. Therefore, the general view of the gray substance against the background of the White resembles the letter N.

The gray substance consists of Nervous cells grouping in the nucleus, the location of which mainly corresponds to the segmental structure of the spinal cord and its primary three-membered reflex arc. First, sensitive, Neuron This arc lies in the cerebrospinal nodes, the peripheral processes begins with receptors in organs and tissues, and centralas part of the rear sensitive roots penetrates through Sulcus Lateralis Posterior in the spinal cord. A borderline zone of white substance is formed around the top of the rear horns, which is a combination of central processing cells of spinal assemblies ending in the spinal cord. Cells of the rear horns form separate groups, or kernels that perceive the nervous impulses that provide various types of sensitivity - somatic sensitive kernels. Among them, the thoracicus nucleus (Columna Thoracica) is distinguished among them (Columna Thoracica), the most pronounced in the breast segments of the brain, located on the top of the horn of a journalist substance, Substantia Gelantines, as well as the so-called own nuclei, Nuclei Proprii. The cells embedded in the back rog form the second, insert, neurons. In the gray substance of the rear horns, scattered cells are also scattered, the so-called bundled cells whose axons pass in the white substance with separate bunches of fibers. These fibers carry nerve impulses from certain spinal cord nuclei into its other segments or serve to communicate with third neurons of the reflex arc embedded in the front horns of the same segment. The processes of these cells coming from the rear horns to the front, are located near the gray substance, along its periphery, forming a narrow border of the white substance surrounding gray on all sides. These are your own spinal cord beams, Fasciculi Proprii. As a result, irritation comes from a certain area of \u200b\u200bthe body can not only be transmitted to the corresponding segment of the spinal cord, but also to capture others. As a result, a simple reflex may involve a whole group of muscles in response, providing a complex coordinated movement, remaining, however, unconditioned.

Front horns contain Third, motor, neurons, whose axons, leaving the spinal cord, make up the front, motor, roots. These cells form the cores of efferent somatic nerves, innervating skeletal muscles, are somatic motor kernels. The latter have the form of short columns and lie in the form of two groups - medial and lateral. The neurons of the medial group innervate the muscles that developed from the dorsal part of the Miotomes (autochthonous muscles of the back), and the lateral - muscles originating from the ventral part of the Miotomes (Ventroleteral Muscles of the Torch and Muscles of Limits); At the same time, the innervirus muscles are located distal than, the lancer is innervating their cells.

The largest number of nuclei is contained in the front horns of cervical Thickening the spinal cord where the upper limbs come from, which is determined by the participation of the latter in human work. In the latter, due to the complication of the movements of the hand as the organ of labor of these nuclei, much more than animals, including anthropoids. Thus, the rear and front horns of the gray substance are related to the innervation of animal life organs, especially the device of the movement, due to the improvement of which in the process of evolution and developed spinal cord.

The front and rear horns in each half of the spinal cord are connected together by the intermediate zone of the gray substance, which is in breast and lumbar Department The spinal cord, throughout the 1st thoracic to 2-3rd lumbar segments, is especially expressed and acts as a side horns, Cornu Laterale. As a result, in these departments, the gray substance on the cross section acquires the appearance of the butterfly. In lateral horns, cells innervating vegetative organs and a group-grouped in the core, which is called intermediolateralis column. Neurites of cells of this nucleus come from the spinal cord in the composition of the front roots.

B. White substance, SUBSTANTIA ALBA, the spinal cord consists of nerve processes, which make up 3 system of nerve fibers:

1) short bundles of associative fibers connecting the spinal cord areas at various levels (afferent and inserting neurons);

2) long centripetal (sensitive, afferent);

3) Long centrifugal (motor, efferent).

The first system (short fibers) refers to its own spinal cord apparatus, and the remaining two (long fibers) make up the conductive apparatus of bilateral ties with the brain.

Own apparatus includes a gray spinal cord substance with rear and front roots and white substance bundles (FasciCuli Proprii), barking gray in the form of a narrow strip. In the development of its own apparatus is the formation of phylogenetically older and therefore retains some primitive structure - segmentality, which is also called the segmental apparatus of the spinal cord, in contrast to the rest of the non-neutral apparatus of bilateral bonds with the brain.

In this way, nervous segment is The cross segment of the spinal cord and the right and left spinal nerves associated with it, developed from one necrometer (non-district). It consists of a horizontal layer of white and gray substance (rear, front and lateral horns) containing neurons whose processes are held in one pair (right and left) spinal nerve and its roots (see Fig. 2). In the spinal cord, 31 segments are distinguished, which are topographically divided by 8 cervical, 12 thoracic, 5 lumbar, 5 sacrats and 1 smokers. Within the nervous segment, a short, simple reflex arc is closed.

Since its own segmental apparatus of the spinal cord arose when it was not yet a head, then the function of it is the implementation of those reactions in response to the external and internal irritation, which in the process of evolution arose before, i.e., innate reactions.

In addition to the cakes, the white substance is located in a white spike, Comissura Alba, which is generated due to the crossroads of the fibers from the front from the Substantiae intermediae centralis; Behind the white spike is absent.

Rear cores contain the fibers of the rear roots of the spinal nerves, which are composed of 2 systems:

1) medially located thin bundle, fasciculus gracilis;

2) laterally located wedge-shaped beam, FasciCULUS CUNEATUS.

Bundles Thin and wedge shaped are carried out from the corresponding parts of the body to the cerebral cortex pulses, providing conscious proprio-chain (muscular-articular feeling) and a skin of a stereogeneity - recognition of items to the touch) sensitivity related to the determination of body position in space, as well as Tactile sensitivity. Side canals contain the following bundles.

A. Rising.

To the back of the brain:

1) Rear spinal cerebelling path, Tractus SpinoCerebellaris Posterior, is located in the back of the side rope by its periphery;

2) Front spinal cerebelling path, Tractus SpinoCerebellaris Anterior, lies with a centralmost of the previous one.

Both spinal cerebelling tract carry out unconscious proprioceptive impulses (unconscious coordination of movements).

To the middle brain:

3) The spinal coat path, TRACTUS Spinotectalis, adjacent to the medial side and front of the Tractus Spinocerbellaris Anterior.

To intermediate brain:

4) lateral spinatelamic path, Tractus Spinothalamicus Lateralis, adjacent from the medial side to Tractus SpinoCerebellaris Anterior, immediately behind Tractus Spinotectalis; It conducts temperature irritations in the dorsal part of the path, and in ventral - pain;

5) Front spinatelamic path, Tractus Spinothalamicus Anterior s. VENTRALIS, similar to the previous one, is located the kleon from the co-lateral and is by carrying out the touch pulses, touch (tactile sensitivity). According to the latest data, this path is located in the front corticle.

B. descending.

From big brain cortex:

1) lateral cortical-spinal (pyramid) path, Tractus CorticOSPinalis (Pyramidalis) Lateralis. This tract is a conscious efferent motorway.

From the middle brain:

2) red-cerebral pathway, Tractus Rubrospinalis; It is an unconscious efferent motorway.

From the back of the brain:

3) Olivospinal Path, Tractus Olivospinalis, lies with a central Tractus Spinocerbellaris Anterior, near the front edge.

Front cable contains downward paths. From the cortex of the brain:

1) The front cortical-spinal (pyramid) path, Tractus CorticOSPinalis (Pyramidalis) Anterior, is a common pyramid system with a lateral pyramid beam.

From the middle brain:

2) TRACTOSPINALIS TRACTOSPINALIS, TRACTUS TECTOSPINALIS, LIRS MEDIA Pyramid Bunch, Limiting Fissiira Mediana Anterior; Thanks to it, reflex protective movements are carried out with visual and auditory irritation - a visual and auditory reflex tract.

A row of beams goes to the front horns of the spinal cord from various cores of the oblong brain relating to the equilibrium and coordination of movements, namely:

3) from the vestibular nerve nuclei - the predvevo-cerebrospinal path, Tractus Vestibulospinalis, - lies on the border of the front and side cords;

4) from Formatio Reticularis - the reticular-spinal path, Tractus Reticulospinalis Anterior, lies in the middle part of the front rope;

5) Own beams, Fasciculi Proprii, directly adjacent to the gray substance and belong to their own spinal cord apparatus.

Spinal cord shells

The spinal cord is dressed in three connective tissue shells, meninges. The shells are following, if you go deep away from the surface: solid shell, DURA MATER; arachnoid, ARACHNOIDEA, and soft shell, Ria Mater. Cranially all 3 shells continue in the same shells of the brain.

Solid shell Spinal cord, Dura Mater Spinalis, covers in the shape of a bag outside the spinal cord. It does not fit close to the walls of the vertebral channel, which are covered with periosteum. The latter is also called an outer leaflet of a solid shell. Epidural space, Cavitas epiduralis, Cavitas Epiduralis is located between the perception and solid shell. It lies with fatty tissue and venous plexus, Plexus Vendsi Vertebreles Interni, in which the venous blood is poured from the spinal cord and vertebrae.

The cranially solid sheath is growing with the edges of the large opening of the occipital bone, and caudally ends at the level of II-III sacral vertebrae, narrowing in the form of a thread, Filum Dirae Matris Spinalis, which is attached to the pad.

Arachnoid The spinal cord, ARACHNOIDEA Spinalis, in the form of a thin transparent insavidial leaf adjacent from the inside to a solid cerebral shell, separated from the last sloping, penetrated subtle crossbars with subdural space, Spatium Subdurale. Between the spider shell and directly covering spinal cord is a soft shell there is a subpatotic space, Cavitas Subarachnoidalis, in which the brain and nerve roots lie freely, surrounded by a large amount of spinal fluid, Liquor Cerebrospinalis. From this space take the spinal fluid for analysis. This space is especially wide in the lower part of the arachnoid bag, where it surrounds the Cauda Equina spinal cord (Cisterna Terminalis). Filling the subpautical space The liquid is in a continuous message with the liquid of the subset spaces and ventricles of the brain.

Between a spider shell and coating spinal cord with a soft cerebral shell in the cervical area from the back, along the midline, partition is formed, Septum Cervie Ale Intermedium. In addition, on the sides of the spinal cord in the front plane there is a gear bunch, a ligamentum denticulatum, consisting of 19-23 teeth, passing between the front and rear roots. The gears serve to strengthen the brain on the spot, not allowing it to be pulled out. Through both Ligg. Denticulatae Podpautic space is divided into front and rear departments.

Soft shell The spinal cord, the Ria Mater Spinalis, covered with the endothelium surface, directly clothe the spinal cord and contains between the two sheets of the vessels, together with which it comes into its furrow and the brainstorm, forming perivascular spaces around the vessels.

Central nervous system (CNS) in human organism represented by two brain elements: head and spinal. In the skeleton of man there is a vertebral channel, where the spinal cord is localized. What functions does he carry out?

It exercises two vitality functions:

• conductive (transmission paths of impulse signals);
• reflex-segmental.

The conductor function is carried out by the transmission of the pulse along the ascending brainstamps to the brain and back to the executing executors on the downstream brainways. The long transmission paths of pulse signals allow them to be transmitted from the spinal cord into different functional departments of the head, and short - provide a link between adjacent segments of the spinal chute.

The reflex function is reproduced by activating a simple reflex arc (knee reflex, extension and bending of hands and legs). Complex reflexes are reproduced with the participation of the brain. The spinal seas is also responsible for performing vegetative reflexes that control the work of the internal environment of a person - digestive, urinary, cardiovascular, sexual systems. The diagram illustrates the functions of the autonomic system in the body. The management of vegetative and motor reflexes is carried out due to proproporeceptors in the thickness of the cerebrospide. The structure and functions of the spinal cord have a number of features in humans.

Consider the structure of the cerebrospinal tightness for a better understanding of which functions it performs.

Anatomical features

The structure of the cerebrospinal tightness of man is not such a simple, as it may seem at the beginning. Externally, the brain resembles a cord with a diameter of up to 1 cm, length in the range of 40-45 cm. Its beginning it takes from the oblong brain department and ends with a horse tail to the end of the spinal column. The vertebrae protect the spinal cord from damage.

The spinal cord is litter, it is formed by a cerebral cloth. On all its length, it has a rounded form in section, exceptions are only the thickening zones, where it is sealing. The cervical thickening is located from the third vertebra of the neck to the first thoracic. Lumbar-sacral flattening is localized in the region of 10-12 vertebra of the chest department.

The front and rear of the spinal cord on its surface has a groove, which divide the organ into two halves. Brain gravity has three shells:

• solid - represents a white shiny dense fibrous tissue rich in elastic fibers;
• cowital - made of connective tissue-coated endothelium;
• vascular - shell from loose connective tissue with rich vessels to ensure the nutrition of the spinal cord.

Between the two lower layers there is a liquid (spinal fluid).

The central deposits of the spinal aliment are made with a gray substance. On the drug cutting of the organ, this substance in the outline has similarity with a butterfly. This component of the brain from the bodies of nerve cells (inserted and motor-type). This section of the nervous system is divided into functional zones: front and rear horns. The first contains the neurons of the motor type, the second have insert nerve cells. Throughout the segment of the spinal aliment from the 7th cervical segment to the 2nd lumbar there are additional side horns. Here are the centers responsible for the functioning of the vegetative NA (nervous system).

The rear horns are characterized by the heterogeneity of its structure. As part of these spinal cord areas there are special kernels performed inserted neurons.

The outer part of the spinal aliment is formed by a white substance made by the butterfly neurons axon. The spinal grooves are conditionally crushed white substance for 3 pairs of cakes, known as: side, rear and front. Axons are combined into several conductive paths:

• associative fibers (short) - provide the relationship of various spinal segments;
• ascending fibers, or sensitive, - transmit nerve signals to the head unit of the CNS;
• downward fibers, or motor, - transmit pulse signals from the bark of the hemispheres to the front horns controlling the executive officers.

Rear channels contain conductors only ascending, and the remaining two pairs are characterized by the presence of descending and upward routes. The number of conductive paths in the corders is different. The table showers the location of the conducting paths in the spinal part of the CNS.

Side rope of conductors:

• the spinal cerebellar path (rear) - transmits in the cerebellum pulse signals of proprioceptive nature;
• the spinal cerebelling path (front) is responsible for contacting the cerebellum bark, where and translates pulse signals;
• the spinal thalamic tract (outdoor side) is responsible for transmitting pulse signals to the brain from receptors that react to pain and temperature change;
• the pyramid tract (outer side) - conducts from the bark of the large hemispheres of motor pulse signals to the cerebrospinal seal;
• the red-cerebral-spinal tract - controls the maintenance of the tone of the skeleton muscles and adjusts the execution of subconscious (automatic) motor functions.

Front channel conductors:

• the pyramid tract (front) - broadcasts the motor signal from the cortex of the UPS TSNS to the bottom;
• the spinal thalax tract (front) - transfers the transfer of pulse signals from tactile receptors;
• the predver-spindy - coordination of conscious movements and equilibrium, and is also characterized by the presence of communication with the oblong brain.

Rear wire conductors:

• the slim bundle of the Gully fibers - is responsible for the transfer of pulse signals from proprigororeceptors, interior beams and skin receptors of the lower body and legs to the brain;
• the wedge-shaped bundle of Burdach fibers - is responsible for the transfer of the same receptors in the brain from the hands and upper parts of the body.

A man's spinal cord in its structure refers to segmental authorities. What number of segments does he have in the human body? Total brain litter contains 31 segments, respectively, spinal departments:

• in cervical - eight segments;
• in breast - twelve;
• in the lumbar - five;
• in the sacrum - five;
• in the smoking - one.

Cerage segments have four roots forming spinal nerves. Rear flares are formed from axons of sensitive neurons, they are included in the rear horns. Rear roots have sensitive ganglia (one at each). Then, in this place, synaps is formed between the sensitive and motor cells of the NA. Axons of the latter form the front roots. The shown scheme demonstrates the structure of the spinal cord and its roots.

In the center of the cerebrospide, the channel is localized on all its length, it is filled with liquor. To the head, hand, light and heart muscle conducting fibers stretch from cervical and uppergrate segments. The belt segments and the pectoral section of the brain give the nerve ending to the muscles of the body and abdominal cavity with its contents. The lower-friendly and sacral segments of a person give the nerve fibers of the legs and muscles of the lower press.