What parts of the cerebral cortex are called regulatory. Functions of the cerebral cortex: what are they

Shoshina Vera Nikolaevna

Therapist, education: Northern Medical University. Work experience 10 years.

Articles written

The brain of modern man and its complex structure is greatest achievement of this species and its advantage, difference from other representatives of the living world.

The cerebral cortex is a very thin layer of gray matter that does not exceed 4.5 mm. It is located on the surface and sides of the cerebral hemispheres, covering them from above and along the periphery.

Anatomy of the cortex or cortex, complex. Each site performs its function and is of great importance in the implementation of nervous activity. This site can be considered the highest achievement of the physiological development of mankind.

Structure and blood supply

The cerebral cortex is a layer of gray matter cells that makes up approximately 44% of the total volume of the hemisphere. The area of ​​the cortex of an average person is about 2200 square centimeters. Structural features in the form of alternating furrows and convolutions are designed to maximize the size of the cortex and at the same time fit compactly within the cranium.

Interestingly, the pattern of convolutions and furrows is as individual as the prints of papillary lines on a person's fingers. Each individual is individual in pattern and.

The cortex of the hemispheres from the following surfaces:

1. Upper lateral. It adjoins the inner side of the bones of the skull (vault).
2. Lower. Its anterior and middle sections are located on the inner surface of the base of the skull, and the posterior ones rest on the cerebellum.
3. medial. It is directed to the longitudinal fissure of the brain.

The most protruding places are called poles - frontal, occipital and temporal.

The cerebral cortex is symmetrically divided into lobes:

• frontal;
• temporal;
• parietal;
• occipital;
• islet.

In the structure, the following layers of the human cerebral cortex are distinguished:

• molecular;
• external granular;
• layer of pyramidal neurons;
• internal granular;
• ganglionic, internal pyramidal or Betz cell layer;
• a layer of multiformate, polymorphic, or spindle-shaped cells.

Each layer is not a separate independent formation, but represents a single, well-functioning system.

Functional areas

Neurostimulation revealed that the cortex is divided into the following sections of the cerebral cortex:

1. Sensory (sensitive, projection). They receive incoming signals from receptors located in various organs and tissues.
2. Motor, outgoing signals sent to effectors.
3. Associative, processing and storing information. They evaluate previously obtained data (experience) and issue an answer based on them.

The structural and functional organization of the cerebral cortex includes the following elements:

• visual, located in the occipital lobe;
• auditory, occupying the temporal lobe and part of the parietal;
• vestibular is less studied and is still a problem for researchers;
• olfactory is on the bottom;
• taste is located in the temporal regions of the brain;
• the somatosensory cortex appears in the form of two areas - I and II, located in the parietal lobe.

Such a complex structure of the cortex suggests that the slightest violation will lead to consequences that affect many functions of the body and cause pathologies of varying intensity, depending on the depth of the lesion and the location of the site.

How is the cortex connected to other parts of the brain?

All areas of the human cortex do not exist in isolation, they are interconnected and form inextricable bilateral chains with deeper brain structures.

The most important and significant is the connection between the cortex and the thalamus. When the skull is injured, the damage is much more significant if the thalamus is also injured along with the cortex. Injuries to the cortex alone are found to be much smaller and have less significant consequences for the body.

Almost all connections from different parts of the cortex pass through the thalamus, which gives reason to combine these parts of the brain into the thalamocortical system. Interruption of connections between the thalamus and the cortex leads to the loss of functions of the corresponding part of the cortex.

Pathways from sensory organs and receptors to the cortes also run through the thalamus, with the exception of some olfactory pathways.

Interesting facts about the cerebral cortex

The human brain is a unique creation of nature, which the owners themselves, that is, people, have not yet learned to fully understand. It is not entirely fair to compare it with a computer, because now even the most modern and powerful computers cannot cope with the volume of tasks performed by the brain within a second.

We are accustomed to not paying attention to the usual functions of the brain associated with the maintenance of our daily life, but even the smallest failure occurred in this process, we would immediately feel it "in our own skin".

“Little gray cells,” as the unforgettable Hercule Poirot said, or from the point of view of science, the cerebral cortex is an organ that still remains a mystery to scientists. We found out a lot, for example, we know that the size of the brain does not affect the level of intelligence in any way, because the recognized genius - Albert Einstein - had a brain that was below average, about 1230 grams. At the same time, there are beings that have brains of a similar structure and even larger size, but have not yet reached the level of human development.

A striking example is the charismatic and intelligent dolphins. Some people believe that once in the deepest antiquity the tree of life split into two branches. Our ancestors went one way, and dolphins went the other way, that is, we may have had common ancestors with them.

A feature of the cerebral cortex is its indispensability. Although the brain is able to adapt to injury and even partially or completely restore its functionality, if part of the cortex is lost, the lost functions are not restored. Moreover, scientists were able to conclude that this part largely determines the personality of a person.

With an injury to the frontal lobe or the presence of a tumor here, after the operation and removal of the destroyed part of the cortex, the patient changes radically. That is, the changes concern not only his behavior, but also the personality as a whole. There have been cases when a good kind person turned into a real monster.

Based on this, some psychologists and criminologists have concluded that intrauterine damage to the cerebral cortex, especially its frontal lobe, leads to the birth of children with antisocial behavior, with sociopathic tendencies. These kids have a high chance of becoming a criminal and even a maniac.

CHM pathologies and their diagnostics

All violations of the structure and functioning of the brain and its cortex can be divided into congenital and acquired. Some of these lesions are incompatible with life, for example, anencephaly - the complete absence of the brain and acrania - the absence of cranial bones.

Other diseases leave a chance for survival, but are accompanied by mental disorders, such as encephalocele, in which part of the brain tissue and its membranes protrude outward through a hole in the skull. The same group also includes an underdeveloped small brain, accompanied by various forms of mental retardation (oligophrenia, idiocy) and physical development.

More a rare variant pathology is macrocephaly, that is, an increase in the brain. Pathology is manifested by mental retardation and convulsions. With it, the increase in the brain can be partial, that is, asymmetric hypertrophy.

Pathologies in which the cerebral cortex is affected are represented by the following diseases:

1. Holoprosencephaly is a condition in which the hemispheres are not separated and there is no full division into lobes. Children with such a disease are born dead or die on the first day after birth.
2. Agyria is the underdevelopment of the gyri, in which the functions of the cortex are impaired. Atrophy is accompanied by multiple disorders and leads to the death of the infant during the first 12 months of life.
3. Pachygyria is a condition in which the primary gyri are enlarged to the detriment of the others. At the same time, the furrows are short and straightened, the structure of the cortex and subcortical structures is disturbed.
4. Micropolygyria, in which the brain is covered with small convolutions, and the cortex does not have 6 normal layers, but only 4. The condition is diffuse and local. Immaturity leads to the development of plegia and muscle paresis, epilepsy, which develops in the first year, mental retardation.
5. Focal cortical dysplasia is accompanied by the presence in the temporal and frontal lobes of pathological areas with huge neurons and abnormal ones. Incorrect cell structure leads to increased excitability and seizures, accompanied by specific movements.
6. Heterotopia is an accumulation of nerve cells that, in the process of development, did not reach their place in the cortex. A solitary condition may appear after the age of ten, large accumulations cause seizures such as epileptic seizures and mental retardation.

Acquired diseases are mainly the consequences of serious inflammations, injuries, and also appear after the development or removal of a tumor - benign or malignant. Under such conditions, as a rule, the impulse emanating from the cortex to the corresponding organs is interrupted.

The most dangerous is the so-called prefrontal syndrome. This area is actually a projection of all human organs, therefore damage to the frontal lobe leads to memory, speech, movements, thinking, as well as partial or complete deformation and a change in the patient's personality.

A number of pathologies accompanied by external changes or deviations in behavior are easy to diagnose, others require more careful study, and removed tumors are subjected to histological examination to rule out a malignant nature.

Alarming indications for the procedure are the presence of congenital pathologies or diseases in the family, fetal hypoxia during pregnancy, asphyxia during childbirth, and birth trauma.

Methods for diagnosing congenital abnormalities

Modern medicine helps prevent the birth of children with severe malformations of the cerebral cortex. For this, screening is performed in the first trimester of pregnancy, which makes it possible to identify pathologies in the structure and development of the brain at the earliest stages.

In a baby born with suspected pathology, neurosonography is performed through the "fontanelle", and older children and adults are examined by conducting. This method allows not only to detect a defect, but also to visualize its size, shape and location.

If the family encountered hereditary problems associated with the structure and functioning of the cortex and the entire brain, a genetic consultation and specific examinations and analyzes are required.

The famous "gray cells" - the greatest achievement of evolution and highest good for a person. Damage can be caused not only by hereditary diseases and injuries, but also by acquired pathologies provoked by the person himself. Doctors urge you to take care of your health, give up bad habits, allow your body and brain to rest and not let your mind be lazy. Loads are useful not only for muscles and joints - they do not allow nerve cells to grow old and fail. The one who studies, works and loads his brain, suffers less from wear and tear and later comes to the loss of mental abilities.

Layer of gray matter covering the cerebral hemispheres of the cerebrum. The cerebral cortex is divided into four lobes: frontal, occipital, temporal, and parietal. The part of the cortex that covers most of the surface of the cerebral hemispheres is called the neocortex because it was formed during the final stages of human evolution. The neocortex can be divided into zones according to their functions. Different parts of the neocortex are associated with sensory and motor functions; the corresponding areas of the cerebral cortex are involved in the planning of movements (frontal lobes) or are associated with memory and perception (occipital lobes).

Cortex

Specificity. Upper layer hemispheres of the brain, consisting primarily of nerve cells with a vertical orientation (pyramidal cells), as well as bundles of afferent (centripetal) and efferent (centrifugal) nerve fibers. In neuroanatomical terms, it is characterized by the presence of horizontal layers that differ in width, density, shape and size of the nerve cells included in them.

Structure. The cerebral cortex is divided into a number of areas, for example, in the most common classification of cytoarchitectonic formations by K. Brodman, 11 areas and 52 fields are identified in the human cerebral cortex. Based on phylogenesis data, a new cortex, or neocortex, old, or archicortex, and ancient, or paleocortex, are distinguished. According to the functional criterion, three types of areas are distinguished: sensory areas that provide reception and analysis of afferent signals coming from specific relay nuclei of the thalamus, motor areas that have bilateral intracortical connections with all sensory areas for the interaction of sensory and motor areas, and associative areas that do not have direct afferent or efferent connections with the periphery, but associated with sensory and motor areas.

CORTEX

The surface covering the gray matter that forms the uppermost level of the brain. In an evolutionary sense, this is the newest neural formation, and approximately 9-12 billion of its cells are responsible for basic sensory functions, motor coordination and control, participation in the regulation of integrative, coordinated behavior and, most importantly, for the so-called "higher mental processes"speech, thinking, problem solving, etc.

CORTEX

English cerebral cortex) - the surface layer covering the cerebral hemispheres, formed mainly by vertically oriented nerve cells (neurons) and their processes, as well as bundles of afferent (centripetal) and efferent (centrifugal) nerve fibers. In addition, the cortex includes neuroglia cells.

A characteristic feature of the structure of C. g. m. is horizontal layering, due to the ordered arrangement of the bodies of nerve cells and nerve fibers. In K. m., 6 (according to some authors, 7) layers are distinguished, differing in width, arrangement density, shape and size of their constituent neurons. Due to the predominantly vertical orientation of the bodies and processes of neurons, as well as bundles of nerve fibers, K. m. has a vertical striation. For the functional organization of K. m., the vertical, columnar arrangement of nerve cells is of great importance.

The main type of nerve cells that make up the K. m. are pyramidal cells. The body of these cells resembles a cone, from the top of which one thick and long, apical dendrite departs; heading towards the surface of the K. g. m., it becomes thinner and fan-shaped divided into thinner terminal branches. Shorter basal dendrites and an axon depart from the base of the body of the pyramidal cell, heading to the white matter, located under the K. m., or branching within the cortex. The dendrites of pyramidal cells bear a large number of outgrowths, the so-called. spines, which take part in the formation of synaptic contacts with the endings of afferent fibers that come to K. m. from other sections of the cortex and subcortical formations (see Synapses). The axons of the pyramidal cells form the main efferent pathways coming from the C. g. m. The size of the pyramidal cells varies from 5-10 microns to 120-150 microns (Betz giant cells). In addition to pyramidal neurons, stellate, fusiform, and some other types of interneurons, which are involved in the reception of afferent signals and the formation of functional interneuronal connections, are part of the cgm.

Based on the peculiarities of the distribution in the layers of the cortex of nerve cells and fibers of various sizes and shapes, the entire territory of the K. g. fields that differ in their cellular structure and functional significance. The classification of cytoarchitectonic formations of K. g. m., proposed by K. Brodman, who divided the entire K. g. m. of a person into 11 regions and 52 fields, is generally accepted.

Based on the data of phylogenesis, K. g. m. is divided into new (neocortex), old (archicortex) and ancient (paleocortex). In the phylogenesis of the KGM, there is an absolute and relative increase in the territories of the new crust, with a relative decrease in the area of ​​the ancient and old. In humans, the new cortex accounts for 95.6%, while the ancient one occupies 0.6%, and the old one - 2.2% of the entire cortical territory.

Functionally, there are 3 types of areas in the cortex: sensory, motor, and associative.

Sensory (or projection) cortical zones receive and analyze afferent signals along fibers coming from specific relay nuclei of the thalamus. Sensory zones are localized in certain areas of the cortex: visual is located in the occipital (fields 17, 18, 19), auditory in the upper parts of the temporal region (fields 41, 42), somatosensory, analyzing the impulse coming from the receptors of the skin, muscles, joints, - in the region of the postcentral gyrus (fields 1, 2, 3). Olfactory sensations are associated with the function of phylogenetically older parts of the cortex (paleocortex) - the hippocampal gyrus.

The motor (motor) area - field 4 according to Brodman - is located on the precentral gyrus. The motor cortex is characterized by the presence in layer V of giant pyramidal Betz cells, the axons of which form the pyramidal tract - the main motor tract descending to the motor centers of the brain stem and spinal cord and providing cortical control of voluntary muscle contractions. The motor cortex has bilateral intracortical connections with all sensory areas, which ensures close interaction between sensory and motor areas.

association areas. The human cerebral cortex is characterized by the presence of a vast territory that does not have direct afferent and efferent connections with the periphery. These areas, connected through an extensive system of associative fibers with sensory and motor areas, are called associative (or tertiary) cortical areas. In the posterior cortex, they are located between the parietal, occipital, and temporal sensory areas, and in the anterior, they occupy the main surface of the frontal lobes. The associative cortex is either absent or poorly developed in all mammals up to primates. In humans, the posterior associative cortex occupies about half, and the frontal regions a quarter of the entire surface of the cortex. In terms of structure, they are distinguished by a particularly powerful development of the upper associative layers of cells in comparison with the system of afferent and efferent neurons. Their feature is also the presence of polysensory neurons - cells that perceive information from various sensory systems.

In the associative cortex there are also centers associated with speech activity (see Broca's center and Wernicke's center). Associative areas of the cortex are considered as structures responsible for the synthesis of incoming information, and as an apparatus necessary for the transition from visual perception to abstract symbolic processes.

Clinical neuropsychological studies show that damage to the posterior associative areas disrupts complex forms of orientation in space, constructive activity, makes it difficult to perform all intellectual operations that are carried out with the participation of spatial analysis (counting, perception of complex semantic images). With the defeat of speech zones, the ability to perceive and reproduce speech is impaired. Damage to the frontal cortex leads to the impossibility of exercising complex programs behaviors that require highlighting meaningful cues based on past experience and anticipation of the future. See Brain Blocks, Cortpicalization, Brain, Nervous system, Development of the cerebral cortex, Neuro-psychological syndromes. (D. A. Farber.)

Reading functions are provided by the lexical center (the center of the lexicon). The center of the lexia is located in the angular gyrus.

Graphic analyzer, graphic center, writing function

Writing functions are provided by the graphic center (graphic center). The center of the graph is located in the posterior part of the middle frontal gyrus.

Counting Analyzer, Calculation Center, Counting Function

The functions of the account are provided by the counting center (calculation center). The center of calculation is located at the junction of the parieto-occipital region.

Praxis, praxis analyzer, praxis center

Praxis is the ability to perform purposeful motor acts. Praxis is formed in the process of human life, starting from infancy, and is provided by a complex functional system of the brain with the participation of the cortical fields of the parietal lobe (lower parietal lobule) and the frontal lobe, especially the left hemisphere in right-handed people. For normal praxis, the preservation of the kinesthetic and kinetic basis of movements, visual-spatial orientation, programming processes and control of purposeful actions are necessary. The defeat of the praxic system at one level or another is manifested by such a type of pathology as apraxia. The term "praxis" comes from the Greek word "praxis" which means "action". - this is a violation of a purposeful action in the absence of muscle paralysis and the preservation of its constituent elementary movements.

Gnostic center, center of gnosis

In the right hemisphere of the brain in right-handers, in the left hemisphere of the brain in left-handers, many gnostic functions are represented. With damage to the predominantly right parietal lobe, anosognosia, autopagnosia, and constructive apraxia may occur. The center of gnosis is also associated with ear for music, orientation in space, and the center of laughter.

memory, thinking

The most complex cortical functions are memory and thinking. These functions do not have a clear localization.

Memory, memory function

Various sections are involved in the implementation of the memory function. The frontal lobes provide active purposeful mnestic activity. The posterior gnostic sections of the cortex are associated with particular forms of memory - visual, auditory, tactile-kinesthetic. The speech zones of the cortex carry out the process of encoding incoming information into verbal logical-grammatical systems and verbal systems. The mediobasal regions of the temporal lobe, in particular the hippocampus, translate current impressions into long-term memory. The reticular formation ensures the optimal tone of the cortex, charging it with energy.

Thinking, the function of thinking

The function of thinking is the result of the integrative activity of the entire brain, especially the frontal lobes, which are involved in the organization of the purposeful conscious activity of a person, man, woman. Programming, regulation and control take place. At the same time, in right-handers, the left hemisphere is the basis of predominantly abstract verbal thinking, and the right hemisphere is mainly associated with concrete figurative thinking.

The development of cortical functions begins in the first months of a child's life and reaches its perfection by the age of 20.

In subsequent articles, we will focus on topical issues of neurology: areas of the cerebral cortex, areas of the cerebral hemispheres, visual, area of ​​the cortex, auditory area of ​​the cortex, motor motor and sensitive sensory areas, associative, projection areas, motor and functional areas, speech areas, primary areas cerebral cortex, associative, functional zones, frontal cortex, somatosensory zone, cortical tumor, absence of the cortex, localization of higher mental functions, problem of localization, cerebral localization, concept of dynamic localization of functions, research methods, diagnostics.

Cortex treatment

Sarclinic uses proprietary methods for restoring the work of the cerebral cortex. Treatment of the cerebral cortex in Russia in adults, adolescents, children, treatment of the cerebral cortex in Saratov in boys and girls, boys and girls, men and women allows you to restore lost functions. In children, the development of the cerebral cortex, the centers of the brain, is activated. In adults and children, atrophy and subatrophy of the cerebral cortex, cortical disturbance, inhibition in the cortex, excitation in the cortex, damage to the cortex, changes in the cortex, sore cortex, vasoconstriction, poor blood supply, irritation and dysfunction of the cortex, organic damage, stroke, detachment , damage, diffuse changes, diffuse irritation, death, underdevelopment, destruction, disease, question to the doctor If the cerebral cortex has suffered, then with proper and adequate treatment it is possible to restore its functions.

. There are contraindications. Specialist consultation is required.

Text: ® SARCLINIC | Sarclinic.com \ Sarlinic.ru Photo: MedusArt / Photobank Photogenica / photogenica.ru The people shown in the photo are models, do not suffer from the described diseases and / or all coincidences are excluded.

The cortex is the most complex highly differentiated section of the CNS. It is divided morphologically into 6 layers, which differ in the content of neurons and the position of nerve variables. 3 types of neurons - pyramidal, stellate (astrocytes), spindle-shaped, which are interconnected.

The main role in the afferent function and excitation switching processes belongs to astrocytes. They have short but highly branched axons that do not extend beyond the gray matter. Shorter and more branching dendrites. They participate in the processes of perception, irritation and unification of the activity of pyramidal neurons.

Bark layers:

Molecular (zonal)

outer granular

Small and medium pyramids

Internal grainy

Ganglionic (layer of the great pyramids)

Layer of polymorphic cells

Pyramidal neurons carry out the efferent function of the cortex and connect the neurons of the cortical regions remote from each other. The pyramidal neurons include Betz's pyramids (giant pyramidal), they are located in the anterior central gyrus. The longest processes of axons are at the pyramids of Betz. A characteristic feature of pyramidal cells is their perpendicular orientation. The axon goes down, and the dendrites go up.

On each of the neurons, there can be from 2 to 5 thousand synaptic contacts. This suggests that the control cells are under a great influence of other neurons in other zones, which makes it possible to coordinate the motor response in response to the external environment.

Fusiform cells are characteristic of layers 2 and 4. In humans, these layers are most widely expressed. They perform an associative function, connect the cortical zones with each other when solving various problems.

The structural organizing unit is the cortical column - a vertical interconnected module, all cells of which are functionally interconnected and form a common receptor field. It has multiple inputs and multiple outputs. Columns that have similar functions are combined into macro columns.

CBP develops immediately after birth, and until the age of 18 there is an increase in the number of elementary bonds in the CBP.

The size of the cells contained in the cortex, the thickness of the layers, their interconnection determine the cytoarchitectonics of the cortex.

Broadman and Fog.

The cytoarchitectonic field is a section of the cortex that is different from others, but similar inside. Each field has its own specifics. Currently, 52 main fields are distinguished, but some of the fields are absent in humans. In a person, areas are distinguished that have corresponding fields.

The bark bears the imprint of phylogenetic development. It is divided into 4 main types, which differ from each other in the differentiation of neuronal layers: paleocortex - an ancient cortex related to olfactory functions: olfactory bulb, olfactory tract, olfactory groove; archeocortex - old cortex, includes areas of the medial surface around the corpus callosum: cingulate gyrus, hippocampus, amygdala; mesocortex - intermediate cortex: outer-lower surface of the island; The neocortex is a new cortex, only in mammals, 85% of the entire cortex of the IBC lies on the convexital and lateral surfaces.

The paleocortex and archeocortex are the limbic system.

The connections of the cortex with subcortical formations are carried out by several types of pathways:

Associative fibers - only within 1 hemisphere, connect neighboring gyrus in the form of arcuate bundles, or neighboring lobes. their purpose is to ensure the holistic work of one hemisphere in the analysis and synthesis of multimodal excitations.

Projection fibers - connect peripheral receptors with KGM. They have different entrances, as a rule, they cross, they all switch in the thalamus. The task is to transmit a monomodal impulse to the corresponding primary zone of the cortex.

Integrative-starting fibers (integrative pathways) - start from the motor zones. These are descending efferent paths, they have crosshairs at different levels, the zone of application is muscle commands.

Commissural fibers - provide a holistic joint work of 2 hemispheres. They are located in the corpus callosum, optic chiasm, thalamus and at the level of 4-cholomium. The main task is to connect equivalent convolutions of different hemispheres.

Limbico-reticular fibers - connect the energy-regulating zones of the medulla oblongata with the CBP. The task is to maintain a general active / passive background of the brain.

2 body control systems: reticular formation and limbic system. These systems are modulating - amplify / attenuate impulses. This block has several levels of response: physiological, psychological, behavioral.

The cerebral cortex is part of most creatures on earth, but it is in humans that this area has reached the greatest development. Experts claim that this contributed to the age-old labor activity that accompanies us throughout our lives.

In this article, we will look at the structure, as well as what the cerebral cortex is responsible for.

The cortical part of the brain plays the main functioning role for the human body as a whole and consists of neurons, their processes and glial cells. The cortex consists of stellate, pyramidal and spindle-shaped nerve cells. Due to the presence of warehouses, the cortical area occupies a fairly large surface.

The structure of the cerebral cortex includes a layered classification, which is divided into the following layers:

• Molecular. It has distinctive differences, which is reflected in the low cellular level. A low number of these cells, consisting of fibers, are closely interconnected
• External granular. The cellular substances of this layer are sent to the molecular layer
• layer of pyramidal neurons. It is the widest layer. Reached the greatest development in the precentral gyrus. The number of pyramidal cells increases within 20-30 microns from the outer zone of this layer to the inner
• Internal granular. Directly the visual cortex of the brain is the area where the inner granular layer has reached its maximum development.
• Internal pyramidal. It consists of large pyramidal cells. These cells are carried down to the molecular layer
• Layer of multimorphic cells. This layer is formed by nerve cells of a different nature, but mostly of a spindle-shaped type. The outer zone is characterized by the presence of larger cells. Cells internal department characterized by a small size

If we consider the layered level more carefully, we can see that the cerebral cortex of the cerebral hemispheres takes on the projections of each of the levels occurring in different parts of the CNS.

Areas of the cerebral cortex

Peculiarities cellular structure The cortical part of the brain is subdivided into structural units, namely: zones, fields, regions and sub-regions.

The cerebral cortex is classified into the following projection zones:

• Primary
• Secondary
• Tertiary

In the primary zone, certain neuron cells are located, to which a receptor impulse (auditory, visual) is constantly supplied. The secondary department is characterized by the presence of peripheral analyzer departments. The tertiary receives processed data from the primary and secondary zones, and is itself responsible for conditioned reflexes.

Also, the cerebral cortex is divided into a number of departments or zones that allow you to regulate many human functions.

Allocates the following zones:

• Sensory - areas in which the zones of the cerebral cortex are located:
  • Spotting
  • Auditory
  • Flavoring
  • Olfactory
• Motor. These are cortical areas, the stimulation of which can lead to certain motor reactions. They are located in the anterior central gyrus. Its damage can lead to significant motor impairment.
• Associative. These cortical regions are located next to the sensory areas. Impulses of nerve cells that are sent to the sensory zone form an exciting process of associative divisions. Their defeat entails severe impairment of the learning process and memory functions.

Functions of the lobes of the cerebral cortex

The cerebral cortex and subcortex perform a number of human functions. The lobes of the cerebral cortex themselves contain such necessary centers as:

• Motor, speech center (Broca's center). It is located in the lower region of the frontal lobe. Its damage can completely disrupt speech articulation, that is, the patient can understand what is being said to him, but cannot answer
• Auditory, speech center (Wernicke's center). Located in the left temporal lobe. Damage to this area can result in the person being unable to understand what the other person is saying, while still remaining able to express themselves. Also in this case, written speech is seriously impaired.

Speech functions are performed by sensory and motor areas. Its functions are related to written speech, namely reading and writing. The visual cortex and the brain regulate this function.

Damage to the visual center of the cerebral hemispheres leads to a complete loss of reading and writing skills, as well as to a possible loss of vision.

In the temporal lobe there is a center that is responsible for the memorization process. A patient with a lesion in this area cannot remember the names of certain things. However, he understands the very meaning and functions of the object and can describe them.

For example, instead of the word "cup", a person says: "this is where liquid is poured in order to then drink."

Pathologies of the cerebral cortex

There are a huge number of diseases that affect the human brain, including its cortical structure. Damage to the cortex leads to disruption of its key processes, and also reduces its performance.

The most common diseases of the cortical part include:

• Pick's disease. It develops in people in old age and is characterized by the death of nerve cells. At the same time, the external manifestations of this disease are almost identical to Alzheimer's disease, which can be seen at the stage of diagnosis, when the brain looks like a dried walnut. It is also worth noting that the disease is incurable, the only thing that therapy is aimed at is the suppression or elimination of symptoms.
• Meningitis. This infection indirectly affects the parts of the cerebral cortex. It occurs as a result of damage to the cortex by infection with pneumococcus and a number of others. It is characterized by headaches, fever, pain in the eyes, drowsiness, nausea
• Hypertonic disease. With this disease, foci of excitation begin to form in the cerebral cortex, and outgoing impulses from this focus begin to constrict blood vessels, which leads to sharp jumps in blood pressure
• Oxygen starvation of the cerebral cortex (hypoxia). This pathological condition most often develops in childhood. It occurs due to a lack of oxygen or a violation of blood flow in the brain. Can lead to irreversible changes in neuronal tissue or death

Most pathologies of the brain and cortex cannot be determined based on the symptoms and external signs that appear. Their detection requires the passage of special diagnostic methods that allow you to examine almost any, even the most hard-to-reach places and subsequently determine the state of a particular section, as well as analyze its work.

The cortical area is diagnosed using various techniques, which we will discuss in more detail in the next chapter.

Conducting a survey

For high-precision examination of the cerebral cortex, methods such as:

• Magnetic resonance and computed tomography
• Encephalography
• Positron emission tomography
• X-ray

An ultrasound examination of the brain is also used, but this method is the least effective in comparison with the above methods. Of the advantages of ultrasound, the price and speed of the examination are distinguished.

In most cases, patients are diagnosed with cerebral circulation. For this, an additional series of diagnostics can be used, namely;

• Doppler ultrasound. Allows you to identify the affected vessels and changes in the speed of blood flow in them. The method is highly informative and absolutely safe for health.
• Rheoencephalography. The job of this method is to register electrical resistance tissues, which allows you to form a line of pulsed blood flow. Allows you to determine the state of blood vessels, their tone and a number of other data. Less informative than the ultrasonic method
• X-ray angiography. This is a standard X-ray examination, which is additionally carried out using intravenous administration of a contrast agent. Then the X-ray is taken. As a result of the spread of the substance throughout the body, all blood flows in the brain are highlighted on the screen.

These methods provide accurate information about the state of the brain, cortex and blood flow parameters. There are also other methods that are used depending on the nature of the disease, the patient's condition and other factors.

The human brain is the most complex organ, and many resources are spent on studying it. However, even in the era of innovative methods of its research, it is not possible to study certain parts of it.

The processing power of processes in the brain is so significant that even a supercomputer is not even close to the corresponding indicators.

The cerebral cortex and the brain itself are constantly being explored, as a result of which the discovery of various new facts about it becomes more and more. The most common discoveries:

• In 2017, an experiment was conducted in which a person and a supercomputer were involved. It turned out that even the most technically equipped equipment is able to simulate only 1 second of brain activity. It took 40 minutes to complete the task.
• The amount of human memory in an electronic unit of measurement of the amount of data is about 1000 terabytes.
• The human brain consists of more than 100 thousand vascular plexuses, 85 billion nerve cells. Also in the brain there are about 100 trillion. neural connections that process human memories. Thus, when learning something new, the structural part of the brain also changes.
• When a person wakes up, the brain accumulates electric field power of 25 W. This power is enough to light an incandescent lamp
• The mass of the brain is only 2% of the total mass of a person, however, the brain consumes about 16% of the energy in the body and more than 17% of oxygen
• The brain is 80% water and 60% fat. Therefore, in order to maintain normal functions, the brain needs healthy eating. Eat foods rich in omega-3 fatty acids (fish, olive oil, nuts) and drink the required amount of fluid daily
• Scientists have found that if a person "sits" on a diet, the brain begins to eat itself. And low levels of oxygen in the blood for several minutes can lead to undesirable consequences.
• Human forgetfulness is a natural process, and the destruction of unnecessary information in the brain allows it to remain flexible. Also, forgetfulness can occur artificially, for example, when drinking alcohol, which inhibits natural processes in the brain

The activation of mental processes makes it possible to generate additional brain tissue that replaces the damaged one. Therefore, it is necessary to constantly develop mentally, which will significantly reduce the risk of dementia in old age.