How does the human brain work? How does the human brain work?

The biggest mystery for scientists is not the vastness of space or the formation of the Earth, but the human brain. Its capabilities exceed those of any modern computer. Thinking, forecasting and planning, emotions and feelings, and finally, consciousness - all these processes inherent in humans, one way or another, take place within a small space of the cranium. The work of the human brain and its study are much more closely related than any other objects and methods of research. In this case they are almost identical. The human brain is studied using the human brain. The ability to understand the processes occurring in the head actually depends on the ability of the “thinking machine” to know itself.

Structure

Today, quite a lot is known about the structure of the brain. It consists of two hemispheres resembling halves of a walnut, covered with a thin gray shell. This is the cerebral cortex. Each of the halves is conventionally divided into several shares. The most ancient parts of the brain in evolutionary terms, the limbic system and brainstem, are located under the corpus callosum, which connects the two hemispheres.

The human brain is made up of several types of cells. Most of them are glial cells. They perform the function of connecting other elements into a single whole, and also take part in amplifying and synchronizing electrical activity. About a tenth of brain cells are neurons various forms. They transmit and receive electrical impulses using processes: long axons, which transmit information from the neuron body further, and short dendrites, which receive signals from other cells. Contacting axons and dendrites form synapses, places where information is transmitted. The long process releases a neurotransmitter, a chemical substance that affects the functioning of the cell, into the synapse cavity; it enters the dendrite and leads to inhibition or excitation of the neuron. The signal is transmitted throughout all connected cells. As a result, the work of a large number of neurons is very quickly excited or inhibited.

Some development features

The human brain, like any other organ of the body, goes through certain stages of its formation. A child is born, so to speak, not in full combat readiness: the process of brain development does not end there. Its most active departments during this period are located in the ancient structures responsible for reflexes and instincts. The cortex functions less well because it consists of a large number of immature neurons. With age, the human brain loses some of these cells, but acquires many strong and orderly connections between the remaining ones. “Extra” neurons that have not found a place in the resulting structures die. How much the human brain works appears to depend on the quality of connections rather than the number of cells.

Common Myth

Understanding the features of brain development helps to determine the discrepancy between the reality of some common ideas about the work of this organ. There is an opinion that the human brain works 90-95 percent less than it can, that is, about a tenth of it is used, and the rest mysteriously sleeps. If you re-read the above, it becomes clear that neurons that are not used cannot exist for long - they die. Most likely, such an error is the result of ideas that existed some time ago that only those neurons that transmit an impulse work. However, per unit time in similar condition There are only a few cells associated with the actions that a person now needs: movement, speech, thinking. After a few minutes or hours, they are replaced by others who were previously “silent”.

Thus, over a certain period of time, the entire brain participates in the work of the body, first with some of its parts, then with others. Simultaneous activation of all neurons, which implies 100% brain function so desired by many, can lead to a kind of short circuit: a person will hallucinate, experience pain, and all possible sensations, shudder with your whole body.

Connections

It turns out that we cannot say that some part of the brain does not work. However, the abilities of the human brain are indeed not fully used. The point, however, is not in “sleeping” neurons, but in the quantity and quality of connections between cells. Any repeated action, sensation or thought is fixed at the neuronal level. The more repetitions, the stronger the connection. Accordingly, using the brain more fully involves building new connections. This is what training is built on. The child’s brain does not yet have stable connections; they are formed and strengthened in the process of the child’s acquaintance with the world. With age, it becomes more and more difficult to make changes to the existing structure, so children learn more easily. However, if you want, you can develop the abilities of the human brain at any age.

Unbelievable but true

The ability to form new connections and relearn produces amazing results. There are cases when she overcame all the limits of the possible. The human brain is a nonlinear structure. With all certainty, it is impossible to identify zones that perform one specific function and no more. Moreover, if necessary, parts of the brain can take over the “responsibilities” of the injured areas.

This is what happened to Howard Rocket, who was doomed to a wheelchair as a result of a stroke. He did not want to give up and, using a series of exercises, tried to develop his paralyzed arm and leg. As a result of everyday hard work, after 12 years he was able not only to walk normally, but also to dance. His brain very slowly and gradually rewired itself so that the unaffected parts of it could perform the functions necessary for normal movement.

Paranormal abilities

The plasticity of the brain is not the only feature that amazes scientists. Neuroscientists do not ignore such phenomena as telepathy or clairvoyance. Experiments are carried out in laboratories to prove or disprove the possibility of such abilities. Research by American and English scientists provides interesting results suggesting that their existence is not a myth. However, neuroscientists have not yet made a final decision: for official science there are still certain boundaries of what is possible, and the human brain, as it is believed, cannot cross them.

Work on yourself

In childhood, as neurons that have not found a “place” die off, the ability to remember everything at once disappears. The so-called eidetic memory occurs quite often in children, but in adults it is an extremely rare phenomenon. However, the human brain is an organ and, like any other part of the body, it can be trained. This means that you can improve your memory, improve your intelligence, and develop creative thinking. It is only important to remember that the development of the human brain is not a matter of one day. Training should be regular, regardless of your goals.

Unusual

New connections are formed at the moment when a person does something differently than usual. The simplest example: There are several ways to get to work, but out of habit we always choose the same one. The task is to choose a new path every day. This elementary action will bear fruit: the brain will be forced not only to determine the path, but also to register new visual signals coming from previously unknown streets and houses.

Such training also includes using the left hand where the right hand is accustomed (and vice versa, for left-handed people). Writing, typing, holding a mouse is so inconvenient, but, as experiments show, after a month of such training, creative thinking and imagination will significantly increase.

Reading

We have been told about the benefits of books since childhood. And these are not empty words: reading increases brain activity, as opposed to watching TV. Books help develop imagination. Crosswords, puzzles, logic games, and chess match them. They stimulate thinking and force us to use those brain capabilities that are usually not in demand.

Physical exercise

How much the human brain works, at full capacity or not, also depends on the load on the whole body. It has been proven that physical training by enriching the blood with oxygen has a positive effect on brain activity. In addition, the pleasure the body receives from regular exercise improves general state and mood.

There are many ways to increase brain activity. Among them there are both specially designed and extremely simple ones, which we, without knowing it, resort to every day. The main thing is consistency and regularity. If you do each exercise once, there will be no significant effect. The feeling of discomfort that occurs at first is not a reason to quit, but a signal that this exercise makes the brain work.

The brain is the most mysterious and mysterious human organ. It’s paradoxical, but our ideas about his work and how it actually happens are diametrically opposed things. Next experiments and hypotheses will lift the curtain on some of the secrets of the functioning of this “stronghold of thinking,” which scientists have not been able to capture to this day.

1. Fatigue is the peak of creativity

Job biological clock — internal system organism, which determines the rhythm of its life activity - has a direct impact on daily life of a person and his productivity in general. If you are a morning person, then it is best to do complex analytical work that requires serious mental investment in the morning or before noon. For night owls, in other words - “night owls” - this is the second half of the day, smoothly turning into night.

On the other hand, scientists advise taking on more creative work that requires activation of the right hemisphere when the body feels physically and mentally exhausted, and the brain is simply no longer able to understand the proof of Goldbach’s ternary problem. It sounds crazy, but if you dig a little deeper, you can still find a rational grain in this hypothesis. Somehow, this explains why moments like "Eureka!" occur while riding public transport after a long day at work or, if history is to be believed, in the bathroom. :)

With a lack of strength and energy, it is extremely difficult to filter the flow of information, analyze statistical data, find and, most importantly, remember cause-and-effect relationships. When it comes to creativity, the listed negative aspects take on a positive connotation, since this type of mental work involves generating new ideas and irrational thinking. In other words, a tired nervous system while working on creative projects more effective.

One of the articles in the popular American magazine Scientific American talks about why distraction plays a role in important role in the process of creative thinking:

“The ability to be distracted is very often the source non-standard solutions and original thoughts. At these moments, a person is less concentrated and can perceive a wider range of information. This “openness” allows you to evaluate alternative solutions to problems from a new angle, promotes the acceptance and creation of completely new, fresh ideas.”

2. The effect of stress on brain size

Stress is one of the most powerful factors affecting the normal functioning of the human brain. Recently, Yale University scientists proved that frequent stress and depression literally reduce the size of the central part of the body's nervous system.

The human brain cannot synchronize decision-making processes in relation to two separate problems. Trying to do two things at the same time only exhausts our cognitive abilities by switching from one problem to another.

If a person is concentrated on one thing, the prefrontal cortex plays the main role, controlling all excitatory and depressive impulses.

“The anterior part of the brain is responsible for forming goals and intentions. For example, the desire “I want to eat that piece of cake” in the form of an exciting impulse passes through the neural network, reaches the posterior prefrontal cortex, and you already enjoy the treat.”

4. Short naps improve mental alertness

The impact of healthy sleep is well known. The question is, what impact does napping have? As it turned out, short “blackouts” throughout the day have an equally positive effect on mental activity.

Memory improvement

After finishing the experiment on memorizing 40 illustrated cards, one group of participants slept for 40 minutes, while the second was awake. As a result of subsequent testing, it turned out that participants who had the chance to take a short nap remembered the cards much better:

“It’s hard to believe, but the group that got enough sleep managed to recall 85% of the cards in their memory, while the rest remembered only 55%.”

Apparently, a short nap helps our central computer “crystallize” memories:

“Research shows that newly formed memories in the hippocampus are very fragile and can be easily erased from memory, especially if space is needed for new information. A short nap appears to “push” recently learned data to the new cortex (neocortex), the long-term storage site for memories, thus protecting them from destruction.”

Improving the learning process

In a study conducted by professors at The University of California, a group of students was given a rather complex task that required learning a lot of new information. Two hours after the start of the experiment, half of the volunteers, just as in the case of cards, continued short period slept for a while.

At the end of the day, the well-rested participants not only completed the task better and learned the material better, but their “evening” productivity significantly exceeded the indicators obtained before the start of the study.

What happens during sleep?

Several recent studies have shown that during sleep, the activity of the right hemisphere increases significantly, while the left hemisphere remains extremely quiet. :)

This behavior is completely unusual for him, since in 95% of the world's population the left hemisphere is dominant. Andrey Medvedev, the author of this study, made a very funny comparison:

"While we sleep, right hemisphere constantly busy around the house.”

5. Vision is the main “trump card” of the sensory system

Despite the fact that vision is one of the five components of the sensory system, the ability to perceive electromagnetic radiation in the visible spectrum is significantly more important than the others:

“Three days after studying any text material, you will remember only 10% of what you read. A few relevant images can increase this figure by 55%.

Illustrations are much more effective than text, partly because reading itself does not produce the expected results. Our brain perceives words as tiny images. It takes more time and energy to understand the meaning of one sentence than to look at a colorful picture.”

There are actually several downsides to relying so heavily on our visual system. Here is one of them:

“Our brain is forced to constantly make guesses, since it has no idea where exactly the visible objects are. A person lives in three-dimensional space, while light falls on the retina of his eye in a two-dimensional plane. So we think of everything we can’t see.”

The picture below shows which part of the brain is responsible for processing visual information and how it interacts with other areas of the brain.

6. Influence of personality type

The mental activity of extroverts increases significantly when a risky deal “burns out” or they manage to pull off some kind of adventure. On the one hand, this is simply a genetic predisposition of sociable and impulsive people, and on the other, different levels of the neurotransmitter dopamine in the brain of different personality types.

“When it became known that the risky deal was successful, increased activity was observed in two areas of the brain of extroverts: the amygdala (corpus amygdaloidum) and the nucleus accumbens.”

The nucleus accumbens is part of the dopaminergic system, which produces feelings of pleasure and influences motivation and learning. Dopamine, produced in the brains of extroverts, pushes them to do crazy things and gives them the opportunity to fully enjoy the events happening around them. The amygdala, in turn, plays a key role in the formation of emotions and is responsible for processing excitatory and depressive impulses.

Other studies have demonstrated that the most a big difference between introverts and extroverts lies in the processes of processing various stimuli entering the brain. For extroverts, this path is much shorter - exciting factors move through the areas responsible for processing sensory information. For introverts, the trajectory of stimuli is much more complex - they pass through areas associated with the processes of remembering, planning and decision-making.

7. The “total failure” effect

Professor social psychology At Stanford University, Elliot Aronson substantiated the existence of the so-called “Pratfall Effect”. Its essence is that by making mistakes, people like us more.

“The one who never makes mistakes is less liked by others than the one who sometimes does stupid things. Perfection creates distance and an invisible aura of unattainability. That is why the winner is always the one who has at least some flaws.

Elliot Aronson conducted a remarkable experiment that confirmed his hypothesis. A group of participants was asked to listen to two audio recordings made during the interviews. In one of them, a man could be heard knocking over a cup of coffee. When participants were asked which applicant they liked most, everyone voted for the clumsy applicant.”

8. Meditation - recharge your brain

Meditation is useful not only for improving attention and maintaining calm throughout the day. Various psycho physical exercise have many positive effects.

Calm

The more often we meditate, the calmer we become. This statement is somewhat controversial, but quite interesting. As it turned out, the reason for this is the destruction of the nerve endings of the brain. Here's what the prefrontal cortex looks like before and after 20 minutes of meditation:

During meditation neural connections weaken significantly. At the same time, connections between the areas of the brain responsible for reasoning and decision-making, bodily sensations and the fear center, on the contrary, are strengthened. Therefore, when experiencing stressful situations, we can evaluate them more rationally.

Creativity

Researchers at Leiden University in the Netherlands, studying goal-oriented and clear-mind meditation, found that participants practicing a style of goal-oriented meditation showed no significant changes in areas of the brain that regulate the process. creative thinking. Those who chose clear-mind meditation far outperformed other participants in subsequent testing.

Memory

Catherine Kerr, Ph.D., a fellow at the MGH Martinos Center for Biomedical Imaging and the Osher Research Center at Harvard Medical School, says meditation improves many mental capacity, in particular, quick memorization of material. The ability to completely disengage from all distractions allows people who practice meditation to concentrate extremely on the task at hand.

9. Exercise - reorganization and training of willpower

Of course, exercise is great for our bodies, but what about our brains? There is exactly the same connection between training and mental activity as there is between training and positive emotions.

“Regular physical activity can significantly improve a person’s cognitive abilities. As a result of the testing, it turned out that people who are actively involved in sports, unlike couch potatoes, have good memory, quickly make the right decisions, without much difficulty concentrate on completing the task at hand and are able to identify cause-and-effect relationships.”

If you have just started exercising, your brain will perceive this event as nothing other than stress. Rapid heartbeat, shortness of breath, dizziness, convulsions, muscle pain etc. - all these symptoms occur not only in gyms, but also in more extreme life situations. If you have felt something similar before, these unpleasant memories will definitely come to mind.

To protect against stress, the brain produces the protein BDNF (brain-derived neurotrophic factor) during exercise. This is why we feel relaxed and ultimately even happy after exercising. Besides - how defensive reaction in response to stress, the production of endorphins increases:

“Endorphins minimize discomfort during exercise, block pain, and promote feelings of euphoria.”

10. New information slows down the passage of time

Have you ever wished that time didn't fly so fast? Probably more than once. Knowing how a person perceives time, you can artificially slow down its progress.

By absorbing a huge amount of information coming from different senses, our brain structures the data in such a way that we can easily use it in the future.

“Since the information perceived by the brain is completely disordered, it must be reorganized and assimilated in a form that is understandable to us. Despite the fact that the data processing process takes milliseconds, new information is absorbed by the brain a little longer. Thus, it seems to a person that time drags on forever.”

What's more strange is that almost every area of ​​the nervous system is responsible for the perception of time.

When a person receives a lot of information, the brain needs a certain time to process it, and the longer this process lasts, the more the passage of time slows down.

When we once again work on painfully familiar material, everything happens exactly the opposite - time flies by almost unnoticed, since we don’t have to put in much mental effort.

In addition, the cerebellum is also responsible for regulation balance and balance muscle tone, while simultaneously working with muscle memory.

Also interesting is the ability of the cerebellum to adapt to any changes in the perception of information in the shortest possible time. It is implied that even with visual impairment (experiment with an invertoscope), a person adapts to the new state in just a few days and can again coordinate the position of the body, relying on the cerebellum.

Frontal lobes

Frontal lobes- This is a kind of dashboard of the human body. She supports him in vertical position, allowing you to move freely.

Moreover, precisely due to frontal lobes a person’s curiosity, initiative, activity and independence are “calculated” at the time of making any decisions.

Also one of the main functions of this department is critical self-assessment. Thus, this makes the frontal lobes something of a conscience, at least in relation to social markers of behavior. That is, any social deviations that are unacceptable in society do not pass the control of the frontal lobe, and, accordingly, are not carried out.

Any injuries to this part of the brain are fraught with:

• behavioral disorders;
• mood changes;
• general inadequacy;
• the meaninglessness of actions.

Another function of the frontal lobes is arbitrary decisions, and their planning. Also, the development of various skills and abilities depends on the activity of this department. The dominant share of this department is responsible for the development of speech and its further control. Equally important is the ability to think abstractly.

Pituitary

Pituitary often called a medullary appendage. Its functions are limited to the production of hormones responsible for puberty, development and functioning in general.

Essentially, the pituitary gland is something like a chemical laboratory in which it is decided what kind of person you will become as your body grows.

Coordination

Coordination, as the skill of navigating in space and not touching objects with different parts of the body in a random order, is controlled by the cerebellum.

In addition, the cerebellum controls such brain functions as kinetic awareness– in general, this is the highest level of coordination, allowing one to navigate the surrounding space, noting the distance to objects and calculating the possibilities of moving in free zones.

Speech

Such important function, as we speak, heads several departments at once:

• Dominant part of the frontal lobe(above), which is responsible for the control of oral speech.
• Temporal lobes are responsible for speech recognition.

Basically, we can say that speech is responsible left hemisphere brain, if you do not take into account the division of the telencephalon into various lobes and sections.

Emotions

Emotional regulation is an area controlled by the hypothalamus, along with a number of other important functions.

Strictly speaking, emotions are not created in the hypothalamus, but it is there that influence is produced. endocrine system person. Already after a certain set of hormones has been produced, a person feels something, however, the gap between the orders of the hypothalamus and the production of hormones can be completely insignificant.

Prefrontal cortex

Functions prefrontal cortex lie in the area of ​​mental and motor activity of the body, which correlates with future goals and plans.

In addition, the prefrontal cortex plays a significant role in creating complex thought patterns,
action plans and algorithms.

home peculiarity is that this part of the brain does not “see” the difference between regulation internal processes organism and following the social framework of external behavior.

When you find yourself faced with a difficult choice that was created largely by your own conflicting thoughts, give thanks for it. prefrontal cortex brain. It is there that differentiation and/or integration of various concepts and objects is carried out.

Also in this department it is predicted the result of your actions, and an adjustment is made in comparison with the result that you want to get.

Thus, we're talking about about volitional control, concentration on the subject of work and emotional regulation. That is, if you are constantly distracted while working and cannot concentrate, then the conclusion drawn prefrontal cortex, was disappointing, and you will not be able to achieve the desired result this way.

The latest proven function of the prefrontal cortex is one of the substrates short term memory.

Memory

Memory is a very broad concept that includes descriptions of higher mental functions that allow one to reproduce previously acquired knowledge, skills and abilities at the right time. All higher animals possess it, however, it is most developed, naturally, in humans.

It is almost impossible to determine exactly which part of the brain is responsible for memory (long-term or short-term). Physiological studies show that the areas responsible for storing memories are distributed over the entire surface of the cerebral cortex.

Mechanism The same way memory works is that a certain combination of neurons is excited in the brain in a strict sequence. These sequences and combinations are called neural networks. Previously, the more common theory was that individual neurons were responsible for memories.

Brain diseases

The brain is an organ like all others in the human body, and therefore also susceptible to various diseases. The list of such diseases is quite extensive.

It will be easier to consider it if you divide them into several groups:

1. Viral diseases. The most common ones are viral encephalitis(muscle weakness, severe drowsiness, coma, confusion and difficulty thinking in general), encephalomyelitis (fever, vomiting, impaired coordination and motor skills of the limbs, dizziness, loss of consciousness), meningitis (high temperature, general weakness, vomiting), etc.
2. Tumor diseases. Their number is also quite large, although not all of them are malignant. Any tumor appears as the final stage of a failure in cell production. Instead of the usual death and subsequent replacement, the cell begins to multiply, filling all the space free from healthy tissue. Symptoms of tumors include headaches and seizures. Their presence can also be easily determined by hallucinations from various receptors, confusion and problems with speech.
3. Neurodegenerative diseases. By general definition, these are also violations in life cycle cells in different parts of the brain. Thus, Alzheimer's disease is described as impaired conduction nerve cells, which leads to memory loss. Huntington's disease, in turn, is the result of atrophy of the cerebral cortex. There are other options. The general symptoms are as follows: problems with memory, thinking, gait and motor skills, the presence of convulsions, tremors, spasms or pain. Also read our article about.
4. Vascular diseases are also quite different, although, in essence, they come down to disturbances in the structure of blood vessels. So, an aneurysm is nothing more than a protrusion of the wall of a certain vessel - which does not make it any less dangerous. Atherosclerosis is a narrowing of blood vessels in the brain, but vascular dementia is characterized by their complete destruction.

The human brain is the most complex biological mechanism created by nature. It has enormous potential, which will probably never be fully realized. The mysterious life of gray matter is huge White spot on the map of human knowledge. How the brain works, how it works - not a single inhabitant of the earth can give a complete and clear answer to these questions.

Everything about the brain is mysterious: from how it arose on the blue planet to its connections with the subtle world of the Universe, which directly affect the depths of a person’s subconscious. These mysteries excite the imagination, spur people to search for new and new unconventional methods of studying the brain matter.

It just so happens that this most perfect mechanism is forced to study itself, but the process of cognition, unfortunately, is not very successful. All the processes that occur in the gray matter are too complex, incomprehensible, different from each other and diverse. Their reflections find themselves in the outside world every second, giving people the opportunity to live an interesting, full life, to cognize the surrounding reality and admire its unity and the struggle of opposites.

The brain occupies a privileged position in the human body. From outside world its delicate tissues are protected cranium, inside - cerebrospinal fluid reliably protects against concussions. Constituting only two percent of the total body weight, this organ, dotted with hundreds of thousands of blood vessels, absorbs twenty percent of the oxygen received by our lungs.

In extreme conditions, when the body is starving, the brain takes the overwhelming share of nutrients. If he loses fifty percent of his body weight, he only loses fifteen percent.

On top of the brain is covered with a thin gray layer with grooves and convolutions. This is nerve tissue called cerebral cortex. Its thickness in different parts of the cerebral hemispheres ranges from 1.3 mm to 4.5 mm. It consists of fourteen to sixteen billion neurons, the main functional element of the nervous system.

It is here that the thinking center is located with direct and feedback connections that are carried out through vertical bundles of fibers. Information comes from the senses to the cortex through nerve impulses and chemical signals. After processing, it is sent back in the form of commands and serves as a guide to action for various parts of the human body.

The bulk of the brain (about 70%) is located in cerebral hemispheres. They are symmetrical and connected to each other by the corpus callosum (a bundle of neuron processes), which ensures the exchange of information between them.

The hemispheres consist of the frontal, temporal, parietal and occipital lobes. In the frontal lobes there are centers that regulate motor activity, in the parietal lobes - zones of bodily sensations. The temporal lobes are responsible for hearing, speech centers, memory, and the occipital lobes convert light rays striking the retina into visual sensations.

Beneath the cortex lie the brain nuclei, which are made up of clusters of neurons, such as the hypothalamus and thalamus. Hypothalamus- a small area of ​​the brain that controls the homeostatic functions of the body. Thalamus responsible for wakefulness and attention.

Responsible for the position of the head, torso and limbs, that is, for ensuring that a person feels comfortable while standing vertically on the ground. cerebellum, which hides under the occipital lobes of the cerebral hemispheres. It also plays a decisive role in developing various skills needed for everyday life.

Average adult brain weight one and a half kilograms. There are individual specimens of gray matter that weigh two kilograms. But large volume and mass are by no means signs of an extraordinary mind and powerful intellect. There are completely different criteria at play here, which have not yet been practically studied.

The brain, in general, is a biological mechanism that is very difficult to study. It is too complex and mysterious to reveal all its secrets to pilgrims to the Land of Consciousness just like that.

Hemispheres
brain

Eg, left and right hemispheres- it's like two brains in one skull. Each of them manages their own affairs, but at the same time helps their colleague. The left deals with logical, abstract thinking, the right with concrete, figurative thinking.

If the left hemisphere takes control of the psyche, then the happy person’s mood will improve. He will become friendly, optimistic, soft and cheerful. But if the right begins to dominate, then the oars will dry up. Depression, irritability, outbursts of anger, aggression are common in this case.

It is also interesting that the specialization of the hemispheres in men is much more pronounced than in the fair sex. By the age of six, in boys, the right hemisphere completely takes over its assigned functions. But in girls it remains more plastic for a long time. Almost throughout life, in women, the ability to spatially perceive the surrounding world is equally characteristic of both halves of the brain.

Such universal specificity can play a positive role in case of physical injury to one of the hemispheres. The second hemisphere will calmly take over the fulfillment of the lost functions of its brother. So men can only envy.

Great interest in studying the work of the brain is given to feelings, thoughts, emotions, which in all their enormous diversity are characteristic only of the crown of nature, that is, you and me. Animals, although they also have brain matter, are not even close to humans.

Spiritual life is a consequence of the work of the brain, which is purely physical and chemical processes or something else, mysterious and incomprehensible? This question has always worried people, but there is still no answer to it.

Back in the 19th century, the rector of the Kyiv Theological Seminary, Archimandrite Boris, outlined his views on this issue in the essay “On the Impossibility of a Purely Physiological Explanation of Human Mental Life.” A high-ranking minister of the Orthodox Church, agreeing that mental life is the work of the brain, at the same time argued that psychic phenomena have their true existence outside the brain. Where then? “This is unknown to us, since it is God’s revelation.”

For the sake of objectivity, it must be said that people of science largely agree with the servant of God. For example, the English physiologist C. Sherrington believed that thought is born outside of matter, but arises in the heads of people, thus misleading them that they themselves brought it into the world.

But the Australian anatomist F. Hallem tried to explain this mystery from a materialistic point of view. He argued that our spiritual life is reproduced in the cerebral cortex. However, this formulation of the question did not lead to anything good. Plunging headlong into the study of physiological processes, trying to attract the spiritual riches of a person to them, this learned man went so far as to create phrenology - a science according to which one can judge the character of people by the configuration of the skull. Subsequently, this hypothesis was adopted by racists of all stripes and shades.

The brain is not sensitive to pain. He can be irritated electric shock, cutting with a scalpel - a person will not feel it. Why didn’t such a rational and practical nature take care of the most important protective function for the most important organ of our body? Apparently because the gray matter cannot be restored. Once it is damaged, nothing can be fixed.

But every cloud has a silver lining. The lack of pain effect allowed gray matter researchers to use electricity in their work. By implanting the thinnest electrodes into various parts of the brain, they were able to find out how individual parts of it work and what they are responsible for.

If you touch the neurons of the temporal region of the cerebral cortex with an electrode, the subject may burst into memories (say, from distant childhood) that would be simply impossible with normal conditions. Irritation of the hypothalamus will cause aggressiveness, and if an electrode is implanted into the reticular formation, fear can be controlled.

The brain tends to remember lost organs. A person loses an arm, years pass after that, and the amputated limb continues to “live” and “sore unbearably.” Such pains are called phantom pains and are well known to doctors. By the way, just implanting electrodes allows you to get rid of this unpleasant factor forever.

This is how, in general terms, the human brain works. In conclusion, I would like to say a few words about rather strange things that, although very rarely, are observed in individual individuals. This is the absence of brain matter. During an autopsy, instead of neurons and glial cells, ordinary water is found in the skull of such a person.

Thus, the German pathologist Joachim Hoffmann, while autopsying the corpse of a patient who had suffered from a mental disorder during his lifetime, discovered a liquid mass in his head instead of the usual picture. The venerable doctor was shocked to the core, but could not explain this phenomenon.

Here's another example. Came home for the holidays English student went to the local hospital complaining of a severe headache. Doctors could not determine the cause for a long time poor condition patient, but after x-ray brains were horrified. This one has young man the gray matter was completely absent: instead of it, liquid splashed. It is interesting that the young man behaved quite adequately, and was in good standing at the university and studied quite successfully.

It is no secret to anyone that when opening the skull of the “leader of the world proletariat” Mr. Ulyanov V.I. (Lenin), Russian medical luminaries also did not find gray matter in his head. Instead of billions and billions of nerve cells, there was water in the head of the Bolshevik terrorist.

The human brain is a perfect, perfectly tuned biological mechanism. There is nothing superfluous in it, but modern people use only 10% of what is necessary and even necessary. As much as 90% of gray matter is unused throughout life. Great amount neurons are never put into operation and do not benefit a person.

What is this benefit? There is no clear answer here. Maybe it's brilliant intuition, maybe teleportation. Ideal memory, spiritual perfection, universal knowledge also cannot be excluded. If all this lies very close, under the skull, then you need to work and work on yourself in order to awaken those sleeping extraordinary forces that can radically change the life of each of us, and therefore all of humanity as a whole.

The article was written by ridar-shakin

Sources: F. Bloom, A. Leiserson “Brain, Mind and Behavior”

HUMAN BRAIN
an organ that coordinates and regulates all vital functions of the body and controls behavior. All our thoughts, feelings, sensations, desires and movements are associated with the work of the brain, and if it does not function, the person goes into a vegetative state: the ability to perform any actions, sensations or reactions to external influences is lost. This article is devoted to the human brain, which is more complex and highly organized than the animal brain. However, there are significant similarities in the structure of the brain of humans and other mammals, as well as most vertebrate species. The central nervous system (CNS) consists of the brain and spinal cord. She is connected with various parts body with peripheral nerves - motor and sensory.
see also NERVOUS SYSTEM . The brain is a symmetrical structure, like most other parts of the body. At birth, its weight is approximately 0.3 kg, while in an adult it is approx. 1.5 kg. When examining the brain externally, attention is primarily drawn to the two cerebral hemispheres, which hide deeper formations. The surface of the hemispheres is covered with grooves and convolutions, increasing the surface of the cortex (the outer layer of the brain). At the back is the cerebellum, the surface of which is more finely indented. Below the cerebral hemispheres is the brain stem, which passes into the spinal cord. Nerves extend from the trunk and spinal cord, along which information from internal and external receptors flows to the brain, and in the opposite direction signals go to the muscles and glands. 12 pairs of cranial nerves arise from the brain. Inside the brain, there is gray matter, consisting mainly of nerve cell bodies and forming the cortex, and white matter - nerve fibers that form pathways (tracts) connecting various parts of the brain, and also form nerves that extend beyond the central nervous system and go to to various organs. The brain and spinal cord are protected by bone cases - the skull and spine. Between the substance of the brain and the bone walls there are three membranes: outer - hard meninges, the inner one is soft, and between them there is a thin arachnoid membrane. The space between the membranes is filled with cerebrospinal fluid, which is similar in composition to blood plasma, is produced in the intracerebral cavities (ventricles of the brain) and circulates in the brain and spinal cord, supplying it with nutrients and other factors necessary for life. Blood supply to the brain is provided primarily by the carotid arteries; at the base of the brain they are divided into large branches going to its various parts. Although the brain weighs only 2.5% of the body's weight, it constantly receives, day and night, 20% of the blood circulating in the body and, accordingly, oxygen. The energy reserves of the brain itself are extremely small, so it is extremely dependent on the supply of oxygen. There are protective mechanisms that can maintain cerebral blood flow in the event of bleeding or injury. A feature of cerebral circulation is also the presence of the so-called. blood-brain barrier. It consists of several membranes that limit the permeability of the vascular walls and the flow of many compounds from the blood into the brain matter; thus, this barrier performs protective functions. For example, many medicinal substances do not penetrate through it.
BRAIN CELLS
The cells of the central nervous system are called neurons; their function is information processing. There are from 5 to 20 billion neurons in the human brain. The brain also includes glial cells; there are about 10 times more of them than neurons. Glia fill the space between neurons, forming a supporting frame nerve tissue, and also performs metabolic and other functions.

The neuron, like all other cells, is surrounded by a semipermeable (plasma) membrane. Two types of processes extend from the cell body - dendrites and axons. Most neurons have many branching dendrites but only one axon. Dendrites are usually very short, while the length of the axon varies from a few centimeters to several meters. The body of a neuron contains a nucleus and other organelles, the same as those found in other cells of the body (see also CELL).
Nerve impulses. The transmission of information in the brain, as well as in the nervous system as a whole, is carried out through nerve impulses. They spread in the direction from the cell body to the terminal section of the axon, which can branch, forming many endings that contact other neurons through a narrow gap - the synapse; the transmission of impulses through the synapse is mediated by chemicals - neurotransmitters. A nerve impulse usually originates in dendrites - thin branching processes of a neuron that specialize in receiving information from other neurons and transmitting it to the neuron's body. There are thousands of synapses on dendrites and, to a lesser extent, on the cell body; It is through synapses that the axon, carrying information from the neuron body, transmits it to the dendrites of other neurons. The axon terminal, which forms the presynaptic part of the synapse, contains small vesicles containing the neurotransmitter. When the impulse reaches the presynaptic membrane, the neurotransmitter from the vesicle is released into the synaptic cleft. The axon terminal contains only one type of neurotransmitter, often in combination with one or more types of neuromodulators (see Brain Neurochemistry below). The neurotransmitter released from the presynaptic membrane of the axon binds to receptors on the dendrites of the postsynaptic neuron. The brain uses a variety of neurotransmitters, each of which binds to its own specific receptor. Connected to receptors on dendrites are channels in the semipermeable postsynaptic membrane, which control the movement of ions across the membrane. At rest, a neuron has an electrical potential of 70 millivolts (resting potential), with the inner side of the membrane being negatively charged relative to the outer. Although there are various transmitters, they all have either an excitatory or inhibitory effect on the postsynaptic neuron. The exciting influence is realized through increasing the flow of certain ions, mainly sodium and potassium, through the membrane. As a result, a negative charge inner surface decreases - depolarization occurs. The inhibitory effect is carried out mainly through a change in the flow of potassium and chlorides, as a result of which the negative charge of the inner surface becomes greater than at rest, and hyperpolarization occurs. The function of a neuron is to integrate all the influences perceived through the synapses on its body and dendrites. Because these influences can be excitatory or inhibitory and not coincident in time, the neuron must calculate the overall effect of synaptic activity as a function of time. If the excitatory effect prevails over the inhibitory one and the depolarization of the membrane exceeds the threshold value, activation of a certain part of the neuron membrane occurs - in the region of the base of its axon (axon tubercle). Here, as a result of the opening of channels for sodium and potassium ions, an action potential (nerve impulse) occurs. This potential propagates further along the axon to its end at a speed of 0.1 m/s to 100 m/s (the thicker the axon, the higher the conduction speed). When the action potential reaches the axon terminal, another type of ion channel that depends on the potential difference is activated: calcium channels. Through them, calcium enters the axon, which leads to the mobilization of vesicles with the neurotransmitter, which approach the presynaptic membrane, merge with it and release the neurotransmitter into the synapse.
Myelin and glial cells. Many axons are covered with a myelin sheath, which is formed by the repeatedly twisted membrane of glial cells. Myelin consists primarily of lipids, which gives characteristic appearance white matter brain and spinal cord. Thanks to the myelin sheath, the speed of the action potential along the axon increases, since ions can move through the axon membrane only in places not covered with myelin - the so-called. Ranvier interceptions. Between interceptions, impulses are conducted along the myelin sheath as if through an electrical cable. Since the opening of a channel and the passage of ions through it takes some time, eliminating the constant opening of the channels and limiting their scope to small areas of the membrane that are not covered with myelin speeds up the conduction of impulses along the axon by about 10 times. Only a portion of glial cells participate in the formation of the myelin sheath of nerves (Schwann cells) or nerve tracts (oligodendrocytes). Much more numerous glial cells (astrocytes, microgliocytes) perform other functions: they form the supporting framework of nervous tissue, provide its metabolic needs and recovery after injuries and infections.
HOW THE BRAIN WORKS
Let's look at a simple example. What happens when we pick up a pencil lying on the table? The light reflected from the pencil is focused in the eye by the lens and directed to the retina, where the image of the pencil appears; it is perceived by the corresponding cells, from which the signal goes to the main sensitive transmitting nuclei of the brain, located in the thalamus (visual thalamus), mainly in that part of it called the lateral geniculate body. There, numerous neurons are activated that respond to the distribution of light and darkness. The axons of the neurons of the lateral geniculate body go to the primary visual cortex, located in the occipital lobe of the cerebral hemispheres. Impulses coming from the thalamus to this part of the cortex are converted into a complex sequence of discharges of cortical neurons, some of which react to the boundary between the pencil and the table, others to the corners in the pencil’s image, etc. From the primary visual cortex, information travels along axons to the associative visual cortex, where image recognition occurs, in this case a pencil. Recognition in this part of the cortex is based on previously accumulated knowledge about the external outlines of objects. Planning a movement (i.e., picking up a pencil) probably occurs in the frontal cortex of the cerebral hemispheres. In the same area of ​​the cortex there are motor neurons that give commands to the muscles of the hand and fingers. The approach of the hand to the pencil is controlled visual system and interoceptors that perceive the position of muscles and joints, information from which enters the central nervous system. When we take a pencil in our hand, the pressure receptors in our fingertips tell us whether our fingers have a good grip on the pencil and how much force must be exerted to hold it. If we want to write our name in pencil, other information stored in the brain will need to be activated to enable this more complex movement, and visual control will help improve its accuracy. The example above shows that performing a fairly simple action involves large areas of the brain, extending from the cortex to the subcortical regions. In more complex behaviors involving speech or thinking, other neural circuits are activated, covering even larger areas of the brain.
MAIN PARTS OF THE BRAIN
The brain can be roughly divided into three main parts: the forebrain, the brainstem, and the cerebellum. IN forebrain secrete the cerebral hemispheres, thalamus, hypothalamus and pituitary gland (one of the most important neuroendocrine glands). The brain stem consists of the medulla oblongata, pons (pons) and midbrain. Large hemispheres are the most most of brain, accounting for approximately 70% of its weight in adults. Normally, the hemispheres are symmetrical. They are connected to each other by a massive bundle of axons (corpus callosum), which ensures the exchange of information.