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A vindictive child and feelings of inferiority. An unenviable fate awaits the child

Some data demonstrating the stages of maturation of brain tissue. Different areas of the brain mature at different times. Knowing this helps explain the emotional and intellectual changes in children, adolescents and young adults. Although no two children develop identically, scientists, using magnetic resonance imaging done by the same children over several years, have established a relationship between certain stages of a child’s development and changes in brain tissue.

0 - 4 years
Early development - In the first few years of life, areas of the brain associated with basic functions change most rapidly. By the age of 4, the areas responsible for the basic senses and general motor skills are almost completely developed. The child can walk, hold a pencil and eat independently.

Sensations - areas responsible for sensations, for example, tactile, are developed almost completely.

Vision - The areas of the brain that control vision are fully mature.

6 years

Language, the region of the brain responsible for speech, is immature but continues to develop rapidly in children up to 10 years of age. The brain is already beginning the process of "thinning", destroying unnecessary connections. This process will intensify in subsequent years, which may be one of the reasons why young children, unlike adults, learn a new language so easily.

Mind - these parts of the brain responsible for abstract thinking, the ability to think rationally and emotional maturity, have not yet developed. Their lack of maturity is one of the reasons why it is difficult for young children to take in too much information, and when given too much choice, children have tantrums.

9 years

Fine motor skills - If gross motor skills are well developed by the age of 5, then the development of fine motor skills develops most actively between 8 and 9 years. It becomes easier for children to write, and in crafts they reach a new level of accuracy.

Mathematics. By the age of 9, the parietal lobes of the brain begin to mature. Their development allows children to master the skills of mathematics and geometry. The rate of learning at this age is very high.

13 years

Judgment - The prefrontal cortex is one of the last areas of the brain to mature. Until it develops, children lack the ability to adequately assess risk or make long-term plans.

Emotions - deep in the limbic system, the ability to experience emotions grows. But this ability is not held back by the prefrontal cortex, which is retarded. This is why teenagers often find it so hard to contain their emotions.

Logic - At this age, the parietal lobes develop very quickly, which are indicated in blue in the figure. The intelligence and analytical abilities of the child grow.

15 years

Specialization - in adolescence, the abundance of nerve connections continues to decrease. Underused links will die to help more active links develop. As a result, the child's brain becomes more specialized and efficient, productive.

17 years

Abstract thinking - in their late teens, children are able to deal with much more complex things than in childhood. The development of these areas leads to a surge in social activity and the manifestation of emotions among older adolescents. Planning, risk assessment and self-control become possible.

21 years old

Higher mental functions. Although, at first glance, it seems that the brain is almost fully developed during adolescence, however, a severe lack of emotional maturity, impulse control, and the ability to make decisions affects until adulthood.

Maturity - The brain of a 21-year-old young man is almost mature. Even after reaching the official "adult" age, we still have areas in the brain that have the potential for development. Emotional maturity and the ability to make decisions will continue to develop in subsequent years.


The cerebral cortex is the center of higher nervous (mental) human activity and controls the implementation of a huge number of vital functions and processes. It covers the entire surface of the cerebral hemispheres and occupies about half of their volume.

The cerebral hemispheres occupy about 80% of the volume of the cranium, and are composed of white matter, the basis of which consists of long myelinated axons of neurons. Outside, the hemisphere is covered with gray matter or the cerebral cortex, consisting of neurons, non-myelinated fibers and glial cells, which are also contained in the thickness of the departments of this organ.

The surface of the hemispheres is conditionally divided into several zones, the functionality of which is to control the body at the level of reflexes and instincts. It also contains centers of higher mental activity of a person, which provide consciousness, assimilation of the information received, allowing one to adapt to the environment, and through it, at the subconscious level, the autonomic nervous system (ANS) is controlled by the hypothalamus, which controls the organs of blood circulation, respiration, digestion, excretion , reproduction, and metabolism.

In order to understand what the cerebral cortex is and how its work is carried out, it is required to study the structure at the cellular level.

Functions

The cortex occupies most of the cerebral hemispheres, and its thickness is not uniform over the entire surface. This feature is due to the large number of connecting channels with the central nervous system (CNS), which ensure the functional organization of the cerebral cortex.

This part of the brain begins to form during fetal development and improves throughout life, by receiving and processing signals from the environment. Thus, it is responsible for the following functions of the brain:

  • connects the organs and systems of the body with each other and the environment, and also provides an adequate response to changes;
  • processes the information received from the motor centers with the help of mental and cognitive processes;
  • consciousness, thinking are formed in it, and intellectual work is also realized;
  • controls the speech centers and processes that characterize the psycho-emotional state of a person.

At the same time, data is received, processed, and stored due to a significant number of impulses that pass through and are formed in neurons connected by long processes or axons. The level of cell activity can be determined by the physiological and mental state of the body and described using amplitude and frequency indicators, since the nature of these signals is similar to electrical impulses, and their density depends on the area in which the psychological process occurs.

It is still unclear how the frontal part of the cerebral cortex affects the functioning of the body, but it is known that it is not very susceptible to processes occurring in the external environment, therefore, all experiments with the impact of electrical impulses on this part of the brain do not find a clear response in the structures . However, it is noted that people whose frontal part is damaged experience problems in communicating with other individuals, cannot realize themselves in any work activity, and they are indifferent to their appearance and third-party opinions. Sometimes there are other violations in the implementation of the functions of this body:

  • lack of concentration on household items;
  • manifestation of creative dysfunction;
  • violations of the psycho-emotional state of a person.

The surface of the cerebral cortex is divided into 4 zones, outlined by the most clear and significant convolutions. Each of the parts at the same time controls the main functions of the cerebral cortex:

  1. parietal zone - responsible for active sensitivity and musical perception;
  2. in the back of the head is the primary visual area;
  3. the temporal or temporal is responsible for the speech centers and the perception of sounds coming from the external environment, in addition, it is involved in the formation of emotional manifestations, such as joy, anger, pleasure and fear;
  4. the frontal zone controls motor and mental activity, and also controls speech motor skills.

Features of the structure of the cerebral cortex

The anatomical structure of the cerebral cortex determines its features and allows it to perform the functions assigned to it. The cerebral cortex has the following number of distinctive features:

  • neurons in its thickness are arranged in layers;
  • nerve centers are located in a specific place and are responsible for the activity of a certain part of the body;
  • the level of activity of the cortex depends on the influence of its subcortical structures;
  • it has connections with all underlying structures of the central nervous system;
  • the presence of fields of different cellular structure, which is confirmed by histological examination, while each field is responsible for the performance of any higher nervous activity;
  • the presence of specialized associative areas makes it possible to establish a causal relationship between external stimuli and the body's response to them;
  • the ability to replace damaged areas with nearby structures;
  • this part of the brain is able to store traces of excitation of neurons.

The large hemispheres of the brain consist mainly of long axons, and also contains clusters of neurons in its thickness, forming the largest nuclei of the base, which are part of the extrapyramidal system.

As already mentioned, the formation of the cerebral cortex occurs even during intrauterine development, and at first the cortex consists of the lower layer of cells, and already at 6 months of the child all structures and fields are formed in it. The final formation of neurons occurs by the age of 7, and the growth of their bodies is completed at 18 years of age.

An interesting fact is that the thickness of the cortex is not uniform over its entire length and includes a different number of layers: for example, in the region of the central gyrus, it reaches its maximum size and has all 6 layers, and areas of the old and ancient cortex have 2 and 3 layers. x layer structure, respectively.

The neurons of this part of the brain are programmed to repair the damaged area through synoptic contacts, thus each of the cells actively tries to repair the damaged connections, which ensures the plasticity of neural cortical networks. For example, when the cerebellum is removed or dysfunction, the neurons that connect it with the final section begin to grow into the cerebral cortex. In addition, the plasticity of the cortex also manifests itself under normal conditions, when a process of learning a new skill takes place or as a result of pathology, when the functions performed by the damaged area are transferred to neighboring parts of the brain or even the hemisphere.

The cerebral cortex has the ability to retain traces of neuronal excitation for a long time. This feature allows you to learn, remember and respond with a certain reaction of the body to external stimuli. This is how the formation of a conditioned reflex occurs, the nervous path of which consists of 3 devices connected in series: an analyzer, a closing apparatus of conditioned reflex connections and a working device. Weakness of the closing function of the cortex and trace manifestations can be observed in children with severe mental retardation, when the conditioned connections formed between neurons are fragile and unreliable, which leads to learning difficulties.

The cerebral cortex includes 11 areas, consisting of 53 fields, each of which is assigned a number in neurophysiology.

Areas and zones of the cortex

The cortex is a relatively young part of the CNS, developed from the terminal part of the brain. The evolutionary formation of this organ occurred in stages, so it is usually divided into 4 types:

  1. The archicortex or ancient cortex, due to atrophy of the sense of smell, has turned into a hippocampal formation and consists of the hippocampus and its associated structures. It regulates behavior, feelings and memory.
  2. The paleocortex, or old cortex, makes up the bulk of the olfactory zone.
  3. The neocortex or neocortex is about 3-4 mm thick. It is a functional part and performs higher nervous activity: it processes sensory information, gives motor commands, and it also forms conscious thinking and speech of a person.
  4. The mesocortex is an intermediate variant of the first 3 types of cortex.

Physiology of the cerebral cortex

The cerebral cortex has a complex anatomical structure and includes sensory cells, motor neurons and internerons that have the ability to stop the signal and be excited depending on the received data. The organization of this part of the brain is built on a columnar principle, in which the columns are made into micromodules that have a homogeneous structure.

The system of micromodules is based on stellate cells and their axons, while all neurons respond in the same way to an incoming afferent impulse and also send an efferent signal synchronously in response.

The formation of conditioned reflexes that ensure the full functioning of the body occurs due to the connection of the brain with neurons located in various parts of the body, and the cortex ensures the synchronization of mental activity with the motility of organs and the area responsible for the analysis of incoming signals.

Signal transmission in the horizontal direction occurs through transverse fibers located in the thickness of the cortex, and transmit an impulse from one column to another. According to the principle of horizontal orientation, the cerebral cortex can be divided into the following areas:

  • associative;
  • sensory (sensitive);
  • motor.

When studying these zones, various methods of influencing the neurons included in its composition were used: chemical and physical irritation, partial removal of areas, as well as the development of conditioned reflexes and registration of biocurrents.

The associative zone connects the incoming sensory information with previously acquired knowledge. After processing, it generates a signal and transmits it to the motor zone. Thus, it is involved in remembering, thinking and learning new skills. Associative areas of the cerebral cortex are located in proximity to the corresponding sensory area.

The sensitive or sensory zone occupies 20% of the cerebral cortex. It also consists of several components:

  • somatosensory, located in the parietal zone is responsible for tactile and autonomic sensitivity;
  • visual;
  • auditory;
  • taste;
  • olfactory.

Impulses from the limbs and tactile organs on the left side of the body are sent along afferent pathways to the opposite lobe of the cerebral hemispheres for further processing.

The neurons of the motor zone are excited by impulses received from muscle cells and are located in the central gyrus of the frontal lobe. The input mechanism is similar to that of the sensory area, as the motor pathways form an overlap in the medulla oblongata and follow to the opposite motor area.

Crinkles furrows and fissures

The cerebral cortex is formed by several layers of neurons. A characteristic feature of this part of the brain is a large number of wrinkles or convolutions, due to which its area is many times greater than the surface area of ​​the hemispheres.

Cortical architectonic fields determine the functional structure of sections of the cerebral cortex. All of them are different in morphological features and regulate different functions. Thus, 52 different fields are allocated, located in certain areas. According to Brodman, this division looks like this:

  1. The central sulcus separates the frontal lobe from the parietal region, the precentral gyrus lies in front of it, and the posterior central gyrus lies behind it.
  2. The lateral furrow separates the parietal zone from the occipital zone. If you spread its lateral edges, then inside you can see a hole, in the center of which there is an island.
  3. The parieto-occipital sulcus separates the parietal lobe from the occipital lobe.

The core of the motor analyzer is located in the precentral gyrus, while the upper parts of the anterior central gyrus belong to the muscles of the lower limb, and the lower parts belong to the muscles of the oral cavity, pharynx and larynx.

The right-sided gyrus forms a connection with the motor apparatus of the left half of the body, the left-sided - with the right side.

The retrocentral gyrus of the 1st lobe of the hemisphere contains the core of the analyzer of tactile sensations and is also connected with the opposite part of the body.

Cell layers

The cerebral cortex performs its functions through the neurons located in its thickness. Moreover, the number of layers of these cells may differ depending on the site, the dimensions of which also vary in size and topography. Experts distinguish the following layers of the cerebral cortex:

  1. The surface molecular layer is formed mainly from dendrites, with a small interspersed with neurons, the processes of which do not leave the layer boundary.
  2. The outer granular consists of pyramidal and stellate neurons, the processes of which connect it with the next layer.
  3. The pyramidal neuron is formed by pyramidal neurons, the axons of which are directed downward, where they break off or form associative fibers, and their dendrites connect this layer with the previous one.
  4. The inner granular layer is formed by stellate and small pyramidal neurons, the dendrites of which go into the pyramidal layer, and its long fibers go into the upper layers or go down into the white matter of the brain.
  5. Ganglionic consists of large pyramidal neurocytes, their axons extend beyond the cortex and connect various structures and departments of the central nervous system with each other.

The multiform layer is formed by all types of neurons, and their dendrites are oriented to the molecular layer, and the axons penetrate the previous layers or go beyond the cortex and form associative fibers that form a connection between gray matter cells and the rest of the functional centers of the brain.

Video: Cerebral cortex

As the cerebral cortex matures, neurons migrate from its depths to the outer layers. Two proteins help neurons to pass through the thickness of already formed zones, while one of them belongs to the class of cadherin proteins that resist all kinds of cell migration. One of the biggest and most interesting mysteries in biology has to do with the process of germ cell migration in the developing embryo. Obviously, in order to form an organ, the cells must line up in a certain order. If we take into account that new cells are formed not "at their destination", but in special zones, from where they then travel to their "workplace", it becomes clear how important the routing and control of the movement of such cells is. An incorrectly indicated direction of migration will lead to defects in the structure and functioning of tissues and organs. Actually, there is a whole class of malformations associated with a violation of the "navigation" of cells in the embryo.

Different organs are sometimes formed in very different ways. Scientists from the Hutchinson Center for Basic Research on Cell Division (USA) attempted to find out the details of the formation of the cerebral cortex.

Rice.

The mature cortex is like a layer cake: it is represented by horizontal layers of nerve cells; neurons in different layers differ in their prescribed functions, but are combined into vertical conducting circuits. If, during the formation of the cortex, the neuron gets into the wrong layer, then in the future there may be violations in the correct transmission of the signal, up to the development of diseases such as epilepsy, schizophrenia and autism.

In the fetus, the brain is formed as if turning inside out: new neurons form in the depths of the maturing cortex and then make their way through the thickets of already fully differentiated neurons of the overlying layers. Having reached the top, they calm down, lose signs of immaturity and form another layer. It was the details of the journey of neurons that remained a mystery to researchers for a long time.

In a paper published in the journal Nature Neuroscience, the scientists describe a signaling system that guides germline neurons in the right direction. At first, nerve cells purposefully move towards the surface of the cortex until they reach a special zone in the germinal brain called the medulla. There are few actual neurons, but many long conductive processes of nerve cells - axons. Once in this zone, migrating neurons seem to lose their orientation and begin to wander in different directions. But above the intermediate zone lie layers of mature nerve cells, and if a "lost" neuron finds itself in such a layer, it again acquires a clear direction of movement.

A special protein reelin helps young nerve cells to get on the right track. It is produced by the neurons of the overlying nerve layers and, thus, it is as if they light a signal beacon for those wandering in the intermediate zone. Mutations in its gene cause disruption in the formation of nerve layers in the cortex of rodents and humans, but it has not yet been clear what exactly this protein does there.

Reelin is synthesized by the uppermost layer of neurons and diffuses down through all layers to the intermediate zone. But at the same time, it does not itself lead young nerve cells upward, but acts through an intermediary in the form of another protein, N-cadherin. This is a membrane protein, which is generally responsible for communication, stabilization, and fastening of cells to each other. Due to cadherins, cells stay in place (these proteins just counteract migration), so the effect of N-cadherin on cell movement turned out to be a big surprise. Under the action of reelin, the content of cadherin in the neuronal membrane increases, and this plays a decisive role in choosing the direction of movement.

Modern science has long proven that a child is not a small adult. Psychologists, relying on the research of scientists, are trying to convey to parents that it is impossible to demand from children what they are not yet ready for. It's not because they don't want to, they're lazy, or they weren't brought up well, it's just that their bodies and brains haven't matured to meet the demands. Therefore, knowledge of the characteristics of child physiology and psychology explains a lot in the behavior of the child and helps modern parents in matters of education.

How does a child's brain mature?

The Caring Alpha website, with a link to The New York Times, acquaints readers with the stages of maturation of brain tissue. For several years, scientists have done MRI of a group of children and have established a connection between the stages of their development and changes in the cerebral cortex. Now it has been scientifically proven: you should not expect analytical abilities from a four-year-old child, he is not physically ready to analyze and predict.

By the age of 4, children have almost fully developed areas responsible for gross motor skills and basic senses. The child can walk, hold a pencil and eat independently. Areas responsible for tactile sensations are fully developed. The part of the brain that controls vision has matured.

At the age of 6, the active development of speech continues: despite the fact that the area of ​​speech development in the diagram is orange, that is, immature, the process is quite intensive. This may explain why young children learn foreign languages ​​so easily. The parts of the brain (yellow and red areas of the prefrontal cortex) responsible for abstract thinking, emotional maturity, and the ability to think rationally have not yet evolved. This is the cause of emotional overload and tantrums.

At the age of 9, the child masters fine motor skills: it becomes easier for schoolchildren to write, crafts are more accurate. Great strides are being made in the development of mathematical sciences: geometry and mathematics.

By the age of 13, the limbic system already allows you to experience strong emotions, but the area of ​​\u200b\u200bthe brain responsible for containing them is not yet developed, hence the problems of adolescent emotionality. Intelligence, analytical skills and logic develop.

15 years - the age when the efficiency of the brain increases. Unnecessary nerve connections die off, but more active connections are strengthened: the brain becomes more “specialized”. At this time, children can choose one area of ​​​​knowledge that is most interesting to them and delve into its study.

At the age of 17, the development of areas of the prefrontal cortex of the brain leads to a surge in social activity, abstract thinking, risk assessment and self-control appear.