Scientists of the Academy of Sciences who studied the functioning of the brain. International Journal of Applied and Basic Research
This review article presents the scientific achievements of many famous scientists in the study of the human brain. The human body is a coordinated work of the brain with other organs and systems. Studies of human brain functions were carried out by such famous scientists as I.M. Sechenov, I.P. Pavlov, N.P. Bekhterev and many others. They explored and demonstrated fundamental ideas about the functions of the brain. Despite many studies, the human brain remains the most mysterious and little-known organ to science. He doesn't reveal his secrets easily. The gray matter of the brain determines the unique, diverse inner world with memories, imagination, emotions and desires. With the development of modern research methods in the field of neurophysiology and the possibility of using the latest equipment, scientists have been able to uncover some of the secrets of the brain.
neurophysiology
medicine
excitation signal
1. Bekhterev V.M. Psyche and life // Book Club Knigovek. – 2015. – P. 220–221.
2. Bekhtereva N.P. The magic of the brain and the labyrinths of life. – M., 2013. – pp. 156–168.
3. Kobozev N.I. Research in the field of thermodynamics of information and thinking processes. – M., 1971. – P. 58–59.
4. Sechenov I.M. Reflexes of the brain. – M.: AST, 2014. – P. 70–80.
5. Medvedev S.V. Secrets of the human brain // Bulletin of the Russian Academy of Sciences - 2005. - No. 6.
6. Strauk B. Secrets of the adult brain. Amazing talents and abilities of a man who has reached the middle of his life. – M.: Career Press, 2011.
7. Stewart-Hamilton Y., Rudkevich L.A. Psychology of aging // Peter, 2010. – pp. 155–169.
With the development of new methods in neurophysiology, the hidden capabilities of the human brain are becoming an object scientific research. V.M. Bekhterev, N.P. Bekhtereva, N.I. Kobozev and many others have proven in their research that the physiological brain is not capable of fully providing conscious and especially unconscious functions due to the low speed of transmission of electrical impulses in interneuronal synapses. It is known that in synapses impulses are delayed by 0.2-0.5 milliseconds, while human thought arises much faster.
At this stage of development of neurophysiology, we have a good idea of how one nerve cell works. Based on the scientific research data of Academician P.K. Anokhin, the emergence of a temporary connection during the formation of conditioned reflexes lies in the sensory-biological convergence of impulses on each cell of the cortex. The PET method makes it possible to trace which areas function when performing certain mental functions, but what is still not well known is what happens inside these areas, in what sequence and what signals nerve cells send to each other and how they interact with each other. The brain map identifies the areas responsible for certain mental functions. But between the cell and the brain region there is another, very important level - a collection of nerve cells, the so-called ensemble of neurons, the functions of which are of great scientific interest.
In his work “Reflexes of the Brain” I.M. Sechenov was the first to assert that the basis of mental processes is the reflex principle of activity. He provided affirmative evidence of the reflex nature of mental activity, that is, all experiences, thoughts, feelings arise as a result of the influence of some physiological stimulus on the body. I.P. Pavlov created his theory of conditioned reflexes, according to which the horizontal cortical temporary connection in the formation of conditioned reflexes is based on the properties of nerve centers - irradiation, dominant excitation of the centers of unconditioned stimuli and pavement. A lot of research was carried out by V.M. Bekhterev, who studied the structure of the brain, associated its functions with it. He proposed a method that allows a thorough study of the pathways of nerve fibers and cells along which the “brain atlas” was created. A real breakthrough in the study of the brain occurs when it is possible to come into direct contact with a brain cell. The method involves direct implantation of electrodes into the brain for diagnostic and medicinal purposes. Electrodes are implanted into various parts of the brain, when stimulated, its activity increases, which makes it possible to study in detail the processes occurring in it.
It was assumed that the brain is divided into clearly demarcated areas, each of which is “responsible” for its own specific function. For example, this is the area responsible for bending the little finger, and this is the area responsible for love. These conclusions were based on simple observations: if a given area was damaged, then its function was accordingly impaired.
It is now becoming clear that everything is not so simple: neurons within different zones interact with each other in a very complex way, and it is impossible to clearly “link” a function to a brain area everywhere in terms of ensuring higher functions, that is, one can only say that this area is related to memory, speech, emotions. It is still difficult to explain that this neural ensemble is not a piece of the brain, but a widely spread network, and only it is responsible for the perception of letters, and another ensemble is responsible for the perception of words and sentences. The complex work of the brain to provide higher species mental activity is similar to the flash of fireworks: at first we see a lot of lights, and then they begin to go out and light up again, winking at each other, some pieces remain dark, others flash. In the same way, an excitation signal is sent to a certain area of the brain, but the activity of the nerve cells within it is subject to its own special rhythms, its own hierarchy. Thanks to these features, the destruction of some nerve cells may be an irreparable loss for the brain, while others may well replace neighboring “relearned” neurons, that is, the property of nerve centers - plasticity - is manifested. A number of neurons are ready to do their job from birth, and there are neurons that can be “educated” during development, so you can try to force them to take over the work of lost cells.
Neurons of the subcortical deep structures of the brain solve the problem with the whole world, together. Whereas the neurons of the cortex, which solve this problem on their own, actually increase its activity, and the frequency of impulses of neurons of deep structures decreases. The higher functions of the brain are ensured by deciphering the neural code, that is, understanding how individual neurons are combined into structures, and the structure into a system and into the whole brain.
According to scientists, a high-frequency field was identified around the brain, which differs from the general human biofield. It got its name - the psychofield. The psychofield ensures the normal high-speed flow of all neurophysiological processes. It has been determined that this psychofield is so high-energy that it requires special carriers, which are pineal gland crystals. They make it possible to hold a huge energy-informational volume in the protein body without denaturing the protein.
In the 60s of the 20th century, Moscow State University professor N.I. Kobozev, studying the phenomenon of consciousness, came to the conclusion that the material physiology of the brain in itself does not provide thinking and other mental functions. This is possible due to external sources of ultra-light particles-psychons, which are the energetic basis of mental and emotional impulses. The research identified an organoid capable of capturing psychon flows. It was found that pineal gland crystals are carriers of holograms that determine the spatiotemporal deployment of all psychogenetic programs laid down at birth. A huge amount of information about various positive and negative programs of human life is stored in the crystals of the pineal gland. The forces of mental and spiritual influence on the crystals of the pineal gland determine how and what programs will be implemented by a person during his life. For many people, this process occurs unconsciously, and they cannot fully realize their energy-informational potential. And for this reason even brilliant people realize their deposits by only 5-7 percent.
In a critical situation, when the problem must be solved immediately, the active production of psychic energy of enormous power begins. And then a spontaneous uncontrolled psychoenergetic process of influencing the crystals of the pineal gland takes place and the program for getting out of the crisis situation is activated in them. Only the production of powerful, highly spiritual energies is short-lived, and when the crisis is resolved, the greatest moments of psychoenergetic tension are forgotten. And not many people can consciously control psychic energy and solve various problems with its help.
Modern neurophysiological science pays special attention to the study of psychoenergetic processes in the brain. There are many institutes and laboratories developing theoretical problems in this area, the developments of which allow practical psychology to deal with the problems of activating the reserves of the human psyche, relying not only on empirical experience, but also on scientific data. Complex non-standard problems can be effectively solved only by activating development programs and awakening the hidden reserves of the psyche. This approach makes it possible to reveal the full potential of the individual and provide effective ways its implementation.
At the age of 40-70 years, the brain has its own characteristics. Intellectual “power” with a healthy lifestyle does not fall with age, but only increases. The maximum manifestation of cognitive functions is in the range of 40-60 years. From the age of 50, when solving problems, a person uses not one hemisphere at the same time, as in young people, but both (cerebral ambidexterity). It is believed that in middle age a person becomes more resistant to stress and can work more effectively under conditions of strong emotional stress. Brain neurons do not die off, as was believed, up to 30%, but connections between them may disappear if a person does not engage in serious mental work. The amount of myelin (the white matter of the brain) in the brain increases with age, and reaches a maximum after 60 years, while intuition increases significantly.
The brain at the age of 40-70 is usually considered not as mature, complete and ready for work, but as in decline and not fully coping with its functions. A number of Russian psychologists have come to the same conclusion: with age, a person’s brain begins to work more efficiently than in youth.
Bibliographic link
Zhumakova T.A., Ryspekova Sh.O., Zhunistaev D.D., Churukova N.M., Isaeva A.M., Alimkul I.O. SECRETS OF THE HUMAN BRAIN // International Journal of Applied and Fundamental Research. – 2017. – No. 6-2. – P. 230-232;URL: https://applied-research.ru/ru/article/view?id=11656 (access date: 09.19.2019). We bring to your attention magazines published by the publishing house "Academy of Natural Sciences"
Every day, your brain generates enough voltage to produce lightning. When you watch TV, your brain barely works, but when you solve elementary school problems, it works hard. And if you try to multitask, you may lose some gray matter.
We talk about the results of interesting research in the field of neurobiology described in our books.
CEO of the brain
When we learn something, the brain uses a number of interconnected areas and regions. For example, the hippocampus almost always operates under the close supervision of the prefrontal cortex. In general, the prefrontal cortex controls our activity - both physical and mental - by receiving signals from the outside and then issuing commands through the neural network of the brain. The prefrontal cortex can be thought of as a kind of boss. It is primarily responsible for assessing the surrounding situation, using working memory, forming impulses and issuing commands for actions, judgments, planning, foresight, and so on - that is, a variety of executive functions.
Illustration from the book “How the Body Works”
As general director The prefrontal cortex of the brain is always in close contact with the executive director - the motor zone of the cerebral cortex, as well as with its other parts.
The hippocampus is like a navigator that receives information from working memory, connects it with existing data, compares it, creates new associations, and sends it to the prefrontal cortex. Scientists believe that memory is a collection of pieces of information dispersed in the brain.
The hippocampus, like a kind of depot, receives fragments of information from the cortex, connects them and sends them back in the form of a new map of neural connections.
Scans of a person's brain show that when he learns a new word, the prefrontal cortex of his brain is activated (as is the hippocampus and some other adjacent areas, such as the auditory cortex). After the chemical signals from glutamate create a new neural circuit and the word is committed to memory, the activity of the prefrontal cortex decreases. She has overseen the initial stages of the project, and can now shift responsibility to other team members and deal with the next problems.
Teenagers' brains are reformatted
Over time, a constantly working neuron becomes covered with a sheath of a special substance called myelin. It significantly increases the efficiency of the neuron as a conductor of electrical impulses. This can be compared to the fact that insulated wires can withstand a significantly greater load than bare wires.
Neurons coated with myelin work without the extra effort that slow, “open” neurons have. Most of the covering of neurons with myelin is complete by the age of two years, as the child's body learns to move, see and hear.
By the age of seven, myelin production decreases, and during puberty it becomes more active.
This is due to the fact that the mammal has to carry out new setting your brain to find the best marriage partner. At this time, our ancestors were often forced to move to new tribes or clans and learn new customs and culture. The increase in myelin production during puberty contributes to all this. Natural selection designed the brain in such a way that it is during this period that it changes the mental model of the world around it.
Brain = movement
Only a moving living creature needs a brain. A study of a small, jellyfish-like sea animal called a sea squirt proves this. Born with a primitive spinal cord and three hundred neurons, this sac-like creature swims in shallow places until it finds a suitable coral extension to which it attaches itself. After the ascidian is born, it has only 12 hours to do this, otherwise it dies. Once attached to the coral, the sea squirt slowly eats its brain. For most of her life she looks more like a plant than an animal. Since the ascidian does not move, it does not need a brain.
As the human species evolved, the purely physical skills of its representatives turned into abstract abilities to anticipate, evaluate, make connections between phenomena, plan, observe themselves, make judgments, correct mistakes, change tactics, and then remember everything that was done in for survival purposes. Today we use the neural circuits that our distant ancestors used to make fire, for example, to learn French.
Lightning and white crows
Although the resting electrical potential of brain cells is less than that of a regular AA battery, the charge passing through their membranes has a colossal voltage - about 50 millivolts per cell. Multiply that by 100 billion cells - at least four times more than it takes to produce lightning during a thunderstorm!
From the moment of birth, the brain generates such electrical impulses throughout its entire structure. Every thought, sensation and action is accompanied by various combinations of them in the form of waves. The doctor sees them on an electroencephalogram (EEG), just as the heart rhythm is seen on an electrocardiogram (ECG). On a graph, the waves generated by the brain appear as continuous lines with increased or decreased frequency, that is, fast and slow.
Communicate. The anterior parts of the frontal lobes are also active during communication, especially when talking while looking into each other’s eyes.
During telephone conversations the frontal lobes have almost no function. That's why it's so important personal meetings and live communication.
Develop fine motor skills. It “turns on” the brain perfectly when a person, for example, cooks food, plays the musical instruments, draws, writes, sews or does other handicrafts. But if you simply move your fingers, that is, make movements that do not involve vision, the frontal parts of the frontal lobes of the brain do not work at all, so such movements are ineffective.
The gut protects the brain
The risk of developing brain diseases is influenced by big influence intestinal bacteria. Their balance and diversity regulate the degree of inflammation in the body. Inflammation is the basis of degenerative conditions, including diabetes, cancer, cardiovascular disease and Alzheimer's disease.
A healthy level of diversity of beneficial bacteria limits the production of inflammatory chemicals. Gut bacteria also produce chemicals important to brain health, including BDNF, various vitamins such as B12, and even neurotransmitters such as glutamate and GABA. They also ferment certain dietary substances, such as polyphenols, into smaller anti-inflammatory compounds that are absorbed into the bloodstream and protect the brain.
BOOK FOR THE 10TH ANNIVERSARY OF THE HUMAN BRAIN INSTITUTE
Medvedev Svyatoslav Vsevolodovich
Institute of Human Brain RAS
The problem of studying the human brain, the problem of the relationship between the brain and the psyche, is one of the most exciting problems posed in science. The goal is to cognize something equal in complexity to the instrument of cognition itself. After all, everything that has been studied so far: the atom, the galaxy, and the brain of an animal was simpler than the human brain. From a philosophical point of view, it is unknown whether a solution to this problem is possible in principle. Do we even have a fundamental opportunity to study this brain, to fully understand what is happening in it? After all, the main means of knowledge are not instruments or methods; again, it remains our human brain. Usually the brain + device that studies some phenomenon or object is more complex than this object, in this case we are trying to act on equal terms - the brain against itself.
It was the enormity of the task that attracted great minds. Hippocrates, Aristotle, Descartes, and many others expressed their ideas about the principles of the brain. In the last century, based on clinical and anatomical comparisons, brain regions responsible for speech were discovered (Broca and Wernicke). However, real scientific research of the brain began in the works of our brilliant compatriot I.M. Sechenov. Further V.M. Bekhterev, I.P. Pavlov. . . Here I will stop listing the names, since there were many outstanding brain researchers in the twentieth century and the danger of missing someone (especially those living today, God forbid) is too great. Great discoveries were made. However, the main difficulty in studying the human brain remained the extreme poverty of methodological approaches: psychological tests, clinical observations, and, starting in the thirties, electroencephalograms. Essentially, this is either a black box paradigm, or an attempt to learn how a TV works from the hum of lamps and transformers and the temperature of the case, or, finally, the functional role of the unit was studied based on what happens to the device if this unit is broken. However, it should be noted that the morphology of the brain has already been studied quite well.
There was another difficulty - the underdevelopment of ideas about the functioning of individual nerve cells. Thus, there was no complete knowledge of the bricks and there were no necessary tools for studying the whole. To a certain extent, we can say that the theoretical concepts were developed much more fully than the experimental basis. Since then, truly gigantic strides have been achieved by the works of Eccles and P.G. Kostyuk in understanding the mechanisms of functioning of the nerve cell. It has become much clearer how a neuron works. However, the question of how the community of nerve cells functions was not automatically resolved.
In fact, the first breakthrough in the study of the functioning of the human brain (as defined by Academician N.P. Bekhtereva) was associated with research in conditions of direct multipoint contact with the human brain when using the method of long-term and short-term implanted electrodes for the diagnosis and treatment of patients. In time, the deployment of this method coincided with the beginning of an understanding of how an individual neuron works, how information is transferred from neuron a to neuron y and along the nerve. For the first time in our country, Academician N.P. Bekhtereva and her staff began to work in direct contact with the human brain.
The results obtained from this first breakthrough allowed us to obtain essential information about the mechanisms of the brain to support higher types of activity. Data were obtained on the life of individual areas of the brain, on the relationship between the cortex and subcortex, on the compensatory capabilities of the brain, and much more. However, there was a problem here: the brain consists of tens of billions of neurons, and with the help of electrodes it was possible to observe dozens, and not always those that were needed for research, but those next to which the therapeutic electrode was located.
In the seventies, due to the dramatic improvement in the elemental base of electronics, a technical revolution took place in the world. Personal computers appeared. Methodological opportunities have emerged to explore the inner world of the nerve cell even more fully, and, what is very important for us, new methods of introscopy have appeared. These are magnetoencephalography, functional magnetic resonance imaging and positron emission tomography. New computing capabilities have practically revived research into the brain's support of higher functions using electroencephalography and evoked potentials. Thus, new technological capabilities built the foundation for a new breakthrough. This actually happened in the mid-eighties.
Thus, scientific interest and the possibility of satisfying it finally coincided. Apparently, this is why the US Congress declared the nineties to be a decade of studying the human brain. This initiative quickly became international. Research is currently underway all over the world human brain Hundreds of the best laboratories are working.
It must be said that at that time (this is not a comparison, but a statement) in the upper echelons of power there were many smart people who supported the state. Professionals who also think about the good of the country. Therefore, we also understood the need to study the human brain and proposed, on the basis of a team created and led by Academician N.P. Bekhtereva, to organize the Institute of the Human Brain of the Russian Academy of Sciences as a scientific and practical center for the study of the human brain and the creation on this basis of new methods for treating its diseases .
What distinguishes the IMP RAS from other physiological and medical institutes similar profile?
We examine first of all exactly what makes a person human. Our institute is specifically focused on research that cannot be studied in animals. Traditionally most of Brain research is carried out on animals, but data obtained on rabbits or rats does not always provide an adequate understanding of the functioning of the human brain. There are phenomena that can only be studied in humans. For example, one of the topics being developed in the positron emission tomography laboratory is the study of the brain organization of speech processing, its spelling and syntax. Agree that this is difficult to study in a rat. We conduct psychophysiological studies on volunteers using the so-called. non-invasive technique. Simply put, without “getting” inside the brain and without causing any particular inconvenience: for example, tomographic examinations or brain mapping using electroencephalographic techniques.
But it happens that a disease or accident “conducts an experiment” on the human brain: for example, the patient’s speech or memory is impaired. In this situation, it is possible to examine those areas of the brain whose functioning is impaired. Or, on the contrary, the patient has lost or damaged a piece of his brain, and scientists are given a unique opportunity to study what “duties” the brain cannot perform with such a violation. This methodology appeared in ancient times, flourished in the second half of the 19th century and is successfully used to this day. It is unacceptable to experiment on a person, but a disease is like an experiment set up by nature itself, and in the process of treating it, invaluable information is obtained about the mechanisms of the brain.
The main directions of the institute’s activities are fundamental research into the organization of the human brain and its complex mental functions: speech, emotions, attention, memory, creativity. In healthy subjects and in patients. At the same time, scientists must search for methods of treating those patients in whom these important brain functions are impaired. That is why one of the main directions of our work is to optimize the diagnosis and treatment of brain diseases. For this purpose, the institute has a clinic with 160 beds. Two tasks - research and treatment - are inextricably linked in the work of our employees. The combination of fundamental research and practical work with patients was one of the main principles of the institute’s work, developed by its scientific director Natalya Petrovna Bekhtereva.
It is the presence of the clinic that largely determines the possibilities of fundamental and applied research into HMI. Therefore, first of all, a few words about her. We have excellent, highly qualified doctors and nurses. It is impossible without this: after all, we are at the forefront, and we need the highest qualifications to perform non-routine, new things. We perform almost all standard manipulations and, along with them, surgical treatment of epilepsy and parkinsonism, psychosurgical operations are carried out, including surgical treatment of obsessive-compulsive syndrome caused by heroin, the famous “brain transplant”, or rather implantation of fetal brain tissue, treatment of magnetism. brain simulation, treatment of aphasia using electrical stimulation and much more. We have accumulated ten years of experience in clinical examinations using positron emission tomography. The figures show a small fraction of what this tomography method can diagnose. We have seriously ill patients, and we try to help using the above methods even when all other attempts have been unsuccessful. Of course, this is not always possible. But it is impossible to give unlimited guarantees in the treatment of people, and if someone gives them, it always raises very serious doubts.
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Consequences of acute cerebrovascular accident.
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Almost every laboratory of the institute is connected to departments of the clinic, and this is the key to the continuous emergence of new methods and approaches to treatment.
A kind of inevitable direction for our Institute of the Human Brain is the study of higher functions of the brain: attention, memory, thinking, speech, emotions, creativity. Several laboratories are working on these problems, including the one I head, the laboratory of Academician N.P. Bekhtereva, laboratory of Doctor of Biological Sciences, USSR State Prize laureate Yu.D. Kropotov. These fundamental studies are one of the main theoretical lines of IMP. Brain functions that are unique to humans or that are especially pronounced in humans are studied using various approaches: a “regular” electroencephalogram, but at a new level of brain mapping, evoked potentials are also at a new level, registration of these processes together with the impulse activity of neurons in direct contact with brain tissue in the conditions of therapeutic and diagnostic use of implanted electrodes and, finally, the technique of positron emission tomography.
The works of Academician N.P. Bekhtereva in this area were widely covered in the scientific and popular science press. She began a systematic study of the cerebral support of mental phenomena even when the overwhelming majority of scientists considered it practically impossible, that is, “it is possible, of course,” but only in principle, in the distant future, using a different technology. How good it is that, at least in science, the truth does not depend on the position of the majority, which, by the way, now says that this research is necessary, a priority, etc.!
I would like to note some interesting results, not the most important ones, but those that I would like to mention within the article. Error detector. Each of us has encountered his work. You leave home, and already on the street a strange feeling begins to torment you: “Something is wrong.” You come back - that's it, you forgot to turn off the light in the bathroom. That is, you missed the stereotypical action, and the control mechanism in the brain immediately turns on. This mechanism was found in the mid-sixties and described by N.P. Bekhtereva and her colleagues in the literature, including Western literature. In the early nineties, error detection was discovered not only in deep structures, but also in the cortex. Studies of the neural mechanisms of error detection in the process of mental activity have statistically reliably confirmed the difference in the reaction of a limited number of neural populations of the parietal cortex of the right hemisphere (field 7) and the Rolandic sulcus (field 1-4) in the form of a phasic increase in the frequency of discharges only in trials with erroneous execution tasks. In the superior parietal cortex, two neuronal populations were found in which selective reactions to erroneous test performance were observed only during retrieval from short-term memory. In one neuronal population, in the perirolandic cortex, such reactions were found only during memorization, and in another, in the parietotemporal region, these reactions were found both during memorization and during retrieval from short-term memory when the test was performed incorrectly.
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In studies of the human brain using intracerebral electrodes, populations of neurons were reliably discovered that selectively react to the erroneous classification of presented images - “error detection”. In the presented post-stimulus histograms (patterns of the current frequency) of discharges, one can see significant differences in the behavior of such a neuronal population (the boundary of putamen and globus pallidum) with different reactions to stimuli. M1 - correct classification; M2 - lack of classification (non-identification); M3 - misclassification. The ordinate axis of the histograms shows relative deviations from the average frequency of discharges in the background. The x-axis is time (bins are marked with dots on the underlying line, each dot is 100ms). The green dotted line indicates the moments of presentation of the image, the signal for the beginning of the answer, and the signal for the end of the subject’s answer. Red lines are indicators of a statistically significant difference in the frequency of neuronal discharges in the corresponding bins: under the histograms - from the frequency in the background; on the lines marked M12, M13, M23 - between the corresponding types of reactions. The length of the red line corresponds to the confidence level. |
Now the error detector has been “rediscovered” in the West by people who know the work of our scientists, but who do not hesitate to directly, say, borrow from “those Russians.” It was even named exactly as in the works of N.P. Bekhtereva. In general, by the way, the disappearance of a great power, to put it mildly, changed the attitude towards us. Cases of direct plagiarism have increased.
Research on so-called brain micromapping. Our studies revealed microcorrelates of various activities. Micro here means at the level of individual groups of cells. We even found such unexpected mechanisms as a detector for the grammatical correctness of a meaningful phrase. For example, "blue ribbon" and "blue ribbon". The meaning is clear in both cases. But there is one small but proud group of neurons that “springs up” when the grammar is broken and signals the brain about it. Why is this necessary? It is likely that the understanding of speech often comes precisely from the analysis of grammar (remember the “glowing bush” of Academician Shcherba), and if there is something wrong with the grammar, additional analysis must be carried out.
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When micromapping the human brain using intracerebral electrodes, correlates of various types of activity were discovered at the level of individual groups of cells (microcorrelates). Post-stimulus histograms (current frequency patterns) of discharges in this case show significant differences in the behavior of the neuronal population in fields 1-4 of the left hemisphere cortex in one of the patients when comparing the reaction to a grammatically correct and grammatically incorrect phrase (difference 1-2). The ordinate axis of the histograms shows relative deviations from the average frequency of discharges in the background. The x-axis is time (bins are marked with dots on the underlying line, each dot is 100ms). The green dotted line indicates the moments of presentation of the image, the signal for the beginning of the answer, and the signal for the end of the subject’s answer. Red lines are indicators of a statistically significant difference in the frequency of neuronal discharges in the corresponding bins: under the histograms - from the frequency in the background; on the lines marked 1-2, 1-3, 1-4, 2-3, 2-4, 3-4 - between the corresponding types of reactions. The length of the red line corresponds to the confidence level. |
Correlates of the difference between concrete and abstract words and accounts were found. In addition to the widespread point of view about the localization of centers of counting and arithmetic operations in the human cerebral cortex, it has been shown that certain neuronal populations in subcortical structures play an important role in the brain mechanisms for supporting digit processing processes. At the same time, in the subcortical structures, as well as in the human cerebral cortex, there are neuronal populations that selectively provide various stages of the processes of processing numbers: such as the perception of the physical characteristics of the presented information, the actual counting and arithmetic operations, naming numbers, preparation future motor response. The data obtained confirm the theory of brain support of mental activity by the cortical-subcortical system with links of varying degrees of rigidity.
Differences in the functioning of neurons during the perception of a word in the native language (cup), a quasi-word in the native language (chokhna) and a foreign word (waht - time in Azerbaijani) are shown. This means that the neural population (together with the entire brain, of course) almost instantly analyzes the phonetic(?) structure of the word and classifies it into types: I understand, I don’t understand, but something is familiar and I obviously don’t understand.
Various involvement of neurons in the cortex and deep structures in ensuring the activity was discovered. In deep structures, an increase in the frequency of discharges is mainly observed, which is not very specific relative to the zone. It’s as if every problem is solved by the whole world. A completely different picture in the cortex. High local specificity of responses. Neuron says: “Come on, guys, shut up, this is my business, and I will decide it myself.” And indeed, all neurons, except for a few, reduce the frequency of impulses, and only those chosen by the brain for a given activity increase it.
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The use of methods for recording complementary physiological indicators with the same test structure makes it possible to see the localization, temporal structure and characteristics of the spatial interaction of the processes of development of emotional reactions in the human brain. Top left - evoked potentials (EP) in tests with the presentation of positive and negative assessments of activity in various structures of the temporal lobe of the human brain, recorded using intracerebral electrodes. Average potentials of seven patients. The red line is the average VP for presenting “5” ratings. The blue line is the average VP for presenting ratings of “2”. The shaded areas are areas of statistically significant differences between EPs for the presentation of positive and negative evaluations.
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One of the main directions of the laboratory’s work is the study of the mechanisms of brain support for emotions. Using the analysis of evoked potentials recorded from implanted electrodes and from the scalp, using the analysis of PET results, the participation of a number of formations of the cortex and subcortex in ensuring the triggering of emotions, the development of positive and negative emotions is shown. The figure demonstrates a complex system of connections between cortical structures that arises during the provision of emotions.
Currently, under the leadership of N.P. Bekhtereva, research has been organized into the brain support of creativity, that is, activity the result of which is not mechanical or pre-programmed actions with the information presented in the task. Let us explain with an example of a task similar to the one we actually used in the study. If the subject is presented with the words: “I, evening, go out, garden, breathe, fresh, air” and asked to compose a story from them, then its content is obvious. What if the same task, but the words: “me, evening, existentialism, electron, duck, radar, ballet, wild boar?” Try to tie them into a story. At present, we cannot yet talk about the completeness of this research, but we can say that it was possible to detect correlates of creative activity both in the EEG and in the cerebral blood flow studied using PET. But this means that it was possible to spy on the organization of perhaps the most human of known activities.
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A study of the brain organization of creative thinking. When comparing the physiological processes of the brain recorded during the process of subjects composing a story from words of different semantic fields (a task with pronounced elements of creativity) and during the process of restoring a coherent text with changes in word forms (such elements are absent), reliable localized differences were revealed. |
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Average data for the group of subjects. The connections are represented by lines connecting the locations of the corresponding electrodes. Red color corresponds to an increase in connections, blue - a decrease. The thickness of the lines reflects the level of statistical significance of the differences in connections.
Electrode mapping of brain activity clearly demonstrates that one of the human hemispheres is not silent at all, as some “scientific” mystics claim, but is active along with the opposite one. |
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In general, thanks to the technique of positron emission tomography (or PET for short), it has become possible to simultaneously study in detail all areas of the brain responsible for complex “human” brain functions. The essence of the method is that a small amount of an isotope is introduced into a substance that participates in chemical transformations inside brain cells, and then we observe how the distribution of this substance changes in the area of the brain that interests us. If the flow of radioactively labeled glucose to this area increases, it means that metabolism has increased, which indicates increased work of nerve cells in this area of the brain.
Now imagine that a person is performing some complex task that requires him to know the rules of spelling or logical thinking. At the same time, his nerve cells are most active in the area of the brain “responsible” for these skills. Strengthening the work of nerve cells can be recorded using PET indirectly, by increasing local blood flow in the activated zone. (More than a hundred years ago, it was shown that increased nerve cell activity leads to an increase in local cerebral blood flow in this area.)
Thus, it was possible to determine which areas of the brain are “responsible” for syntax, spelling, the meaning of speech and for solving other problems. We present subjects with variously organized tasks, during which it is necessary to “use” certain properties of speech. For example, individual words, sentences, connected text. By comparing PET images obtained from this activity, we can determine where in the brain processing of an individual word occurs, where is the syntax, and where is the meaning of the text. Zones are visible that are activated when words are presented, no matter whether they had to be read or not. Zones responsible for the meaning of the text, and others. Interestingly, and this will be discussed below, it was possible to discover zones that are activated to “do nothing.”
In studies of the brain mechanisms of speech perception based on the results of a PET study using local blood flow, it was found that when reading a text, the main changes occur in the area of the left temporal lobe (38, 22, 43, 41, 42, 40 and 38 fields), 3, 4, 6 , 44, 45, and 46 fields and on the right in the area of 22, 41, 42, 38, 1, 3, and 6 fields. Comparison with data from other researchers allows us to correlate some of these results with the processes of memorizing, reading words, and understanding the meaning of a. It became possible to separate areas associated with the perception of meaning and memorization of text from areas that are associated with the processing of individual words. These results correlate with those previously obtained using analysis of neural activity. The results obtained from the study of neural activity about the involvement of brain areas located in other areas in the production of speech, along with classical zones, were also confirmed. When studying the cerebral support of speech, areas of the human cerebral cortex involved in providing various stages of analysis of orthographic and syntactic characteristics were mapped. The medial extrastriate cortex has been shown to be involved in processing the orthographic structure of words; a significant part of the left superior temporal cortex (Wernicke's area) is most likely involved in voluntary semantic analysis, and less likely in the processing of syntactic structure; the inferior frontal cortex of the left hemisphere is a link in the system of verbal semantic analysis, its possible participation in syntactic processing is limited to the processing of word forms and functional words, but not the order of their occurrence in a sentence; The anterior part of the superior temporal cortex is involved in determining the syntactic structure of a phrase based on the analysis of word order. Based on the analysis of cerebral blood flow, it was possible to show that when a person is presented with a coherent text, even without the need to read it - the task was to count the appearance of a certain letter - the brain is nevertheless significantly, more intensively involved in processing the linguistic characteristics of the stimuli, which is expressed in the activation of certain zones than when presented with the same task of the same words, but unrelated, mixed in random order.
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The brain's system of involuntary syntactic processing. Projections onto the lateral surfaces of the cerebral hemispheres of activation areas (p< 0,01), полученных в условиях поиска буквы в связном тексте, предъявляемого бегущей строкой, в сравнении с аналогичной задачей при предъявлении синтаксически |
Brain activation during text processing. Areas of local increase in the functional activity of nervous tissue obtained under conditions of the comprehension task readable text, compared to the task of finding a letter in a meaningless letter sequence. Shown are projections of significant zones (p< 0,0001) активаций на три ортогональных плоскости (вид справа, сзади и сверху, соответственно, в верхнем ряду справа и слева, в нижнем ряду - слева). Внизу справа показаны проекции кортикальных латерал ьных активций в левом полушарии на реконструированную поверхность левого полушария «стандартного» мозга. |
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Brain activation at rest.
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The problem of brain support for human attention is very important. Both my laboratory and the laboratory of Yu.D. Kropotov are working on this at our institute. Research is being conducted jointly with a team of scientists led by Finnish professor R. Naatanen, who discovered the electrophysiological correlates of the so-called mechanism of involuntary attention. To understand what we are talking about, imagine the situation: a hunter sneaks through the forest, tracking down his prey. But he himself is prey for a predatory animal, which he does not notice, because he is only determined to search for a deer or a hare. And suddenly a random crackling sound in the bushes, perhaps not very noticeable among the chirping of birds and the noise of the stream, instantly switches his attention and gives a signal: “danger is nearby.” The mechanism of involuntary attention was formed in humans in ancient times as a security mechanism, but it still works today: for example, a person is driving a car, listening to the radio, hears the screams of children playing on the street, perceives all the sounds of the surrounding world, his attention is scattered, and suddenly the quiet knock of an engine instantly switches his attention to the car - he realizes that something is wrong with the engine (by the way, this is a phenomenon fundamentally similar to an error detector). This attention switch works for every person. We discovered PET correlates of this mechanism, and Yu.D. Kropotov discovered electrophysiological correlates in patients with implanted electrodes. Funny. We completed this work before a very important and prestigious symposium. In a hurry. We went there, and where we both had reports, with surprise and a “feeling of deep satisfaction” we unexpectedly noticed that the activation was in the same zones. Yes, sometimes two people sitting next to each other need to travel to another country to talk.
What did we get? PET correlates of unconscious attention, the so-called. the phenomenon of mismatch negativity - involuntary switching of attention to deviant acoustic stimuli. Studies have been carried out on the negativity of mismatch when presenting both simple auditory stimuli (tones) and more complex ones: chords and phonemes. For all these types of stimuli, similar correlates of mismatch negativity were found. The first activation pattern is located in the superior temporal regions (auditory cortex) of both hemispheres, indicating a response to changes in tone, even minor ones, with more pronounced activation of the temporal cortex occurring when deviant stimuli are mixed with standard ones than when only deviant stimuli are presented. More pronounced activation was present in the right hemisphere, consistent with previous electrophysiological findings. The second pattern was activation of the frontal lobe, and they were present both when stimulated with only deviant stimuli and when combined with standard and deviant stimuli. There were foci of prefrontal activation in the frontal lobe, which also corresponds to previous electrophysiological data, as well as in the region of the middle and superior frontal gyri. Activations of the anterior cingulate cortex and bilateral activations of the posterior parietal areas were also noted (right-sided parietal activation was described with magnetoencephalography). Activations of the frontal lobe most likely underlie the subject's conscious belief in changing a stimulus that has already been unconsciously identified by the auditory cortex of both hemispheres. This role of the frontal lobe as an attentional shifting structure is supported by the pronounced activation patterns that are evoked by deviant tones when presented alone at relatively long, irregular intervals, as known from previous studies. Activations of the anterior cingulate cortex and parietal cortex may be involved in brain mechanisms of attention switching. Additionally, activation of the cortex of the Reilly insula was revealed, which was not known from previous electro- and magnetoencephalographic studies, but similar activations were also obtained from the results of direct registration of evoked potentials from these structures through implanted electrodes in the action programming laboratory of the Institute of Chemistry of Chemistry of the Russian Academy of Sciences. The role of this structure in supporting attention processes is currently unknown and is subject to further study. Thus, patterns of brain activation were identified that shed light on the mechanisms by which deviant auditory stimuli cause involuntary shifts of attention.
If attention mechanisms are disrupted, then we can talk about illness. In the laboratory of Yu.D. Kropotov study children with so-called attention deficit hyperactivity disorder. These are difficult children, often boys, who cannot concentrate in class, they are often scolded at home and at school, but in fact they need to be treated because some certain mechanisms of brain function are disrupted. Until recently, this phenomenon was not considered a disease, and “forceful” methods were considered the best method of combating it. We can now not only determine the presence of this disease, but also offer treatment for such difficult children.
Attention deficit disorder is characterized by three components: 1) inattention - the inability to concentrate on one thing for a long time; 2) impulsiveness - the inability to delay a response to changes in the environment in order to more carefully analyze these changes; 3) pathological distractibility - an excessive orienting reaction to any external stimulus that is not related to the task. Very often these disorders are accompanied by hyperactivity, i.e. such a condition when general motor and speech activity significantly exceeds that normally. It occurs in 5-10% of schoolchildren. This behavioral disorder does not allow children suffering from this disease to adapt to school and family; it causes negative reactions from parents, teachers and even peers, entails poor academic performance and very often ultimately leads to alcoholism, drug addiction and other antisocial manifestations. It is because of these consequences that attention deficit disorder is under close attention among doctors, teachers and scientists in the USA, Japan and Western Europe. In these countries, significant funds from the budget and private capital are spent on the prevention, diagnosis and treatment of this disease. Since 1995, the Laboratory of Neurobiology of Action Programming at the Institute of Human Brain of the Russian Academy of Sciences has included in its scientific work plan research into electrophysiological correlates of attention deficit with the aim of using them for objective diagnosis of this disease.
However, I would like to upset some young readers. Not every prank is associated with this disease, and then. . . “forceful” methods are justified.
A person, living in a complex and constantly changing world, has a huge repertoire of action programs that he is able to carry out in various situations. These actions include simple and complex perceptual functions (such as judging the color or shape of a visual image), various mental operations (such as arithmetic calculation or playing chess), and goal-directed motor acts (such as turning the head in the desired direction and moving a chess piece). At each moment of time, a person chooses (selects) from this entire huge set of action programs only those that are most adequate in a given situation. The brain processes responsible for this choice are usually grouped under the name control processes (in the broad sense e) or selective attention and motor control (in the narrow sense e). Research from Kropotov’s laboratory has shown that central control mechanisms are divided into processes of involvement in a necessary action (initiation, selection of a sensory-motor-cognitive act) and processes of suppression of unnecessary action. These two mechanisms involve forward and backward pathways in circuits connecting the cortex, basal ganglia, thalamus, and cortex in a complex loop feedback. It has been shown that the processes of involvement and suppression are detected in the positive components of evoked potentials recorded from the surface of the scalp, and in children with attention deficit hyperactivity disorder the components of involvement and suppression are significantly reduced in amplitude. Based on the results of these studies, it can be assumed that in children with attention deficit hyperactivity disorder, the mechanisms of engagement and inhibition of actions are impaired due to hypofunction of the basal ganglia.
Why is this important now? Because an objective criterion has appeared for diagnosing this syndrome and monitoring its treatment. As it turned out in the course of numerous studies, in some cases it is not children who need to be treated (they have nothing wrong with their brains), but their parents, who place too high demands on their children. The use of a new diagnostic method made it possible not only to make a correct diagnosis, but also to monitor how effective a particular method is in treating the disease.
In addition, the laboratory has proposed a new treatment method based on the phenomenon of biofeedback, when the discrepancy between those biopotentials that should be normal and those that actually exist is displayed in one form or another on the monitor, and the patient tries to “train” » your brain so as to get as close to normal as possible. Strange as this description may sound, this method brings good results and, most importantly, unlike drug therapy, it is absolutely harmless. In the laboratory of Yu.D. Kropotova are also trying to find other effective treatment methods. Methods are used to activate the metabolic activity of the brain: the method of micropolarization and electrical stimulation of the brain through cutaneous electrodes, as well as herbal medicine methods.
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Direct and indirect pathways in cortico-subcortical-cortical interactions (left), prestimulus histograms (PSTH) and thalamic evoked potentials (ERPs) in response to go-go (GO) and inhibition of prepared action (NOGO) stimuli (right) . “Switching on” of the direct pathway leads to activation of thalamic neurons and a positive wave in evoked potentials. |
Conducted psychophysiological studies with registration of evoked potentials of the brain showed the presence of several subgroups of patients diagnosed with attention disorders, related to the violation of various attention functions in humans, and each of these subgroups requires its own adequate treatment methods. What can give good results in children with a dominant disorder of the processes of involvement in activities does not work in children with a dominant disorder of the inhibition processes and vice versa. This is why it is important to have a range of treatments for attention deficit disorder. By treating such children, we contribute to the prevention of drug addiction and alcoholism, since these children are at risk for these vices. As foreign statistics show, the likelihood of becoming a drug addict or alcoholic for such children is an order of magnitude higher than for normal children. Children without “brakes” are easily involved in criminal companies and begin to stimulate themselves with drugs and alcohol. Let us note in parentheses that in the West, psychostimulants (such as Ritlin), the mechanism of action of which is similar to the action of cocaine, are used to treat children with attention disorders. Therefore, in the United States they jokingly talk about two drug mafias: Colombian and pharmaceutical. In Russia, at our Institute, we are trying to find other alternative methods of treatment. And we succeed!
In addition to involuntary attention, there is also selective attention. The so-called attention to the cocktail reception. Everyone is talking at once, and you only follow your interlocutor, suppressing the uninteresting chatter of your neighbor on the right. A similar situation is shown in the figure. Stories are told in both ears. Different. In the first case, we follow the story in the right ear, and in the third, in the left. You can see how the activation of brain regions changes. Note, by the way, that the activation for history in the right ear is much less. Why? But because most people take the phone in their right hand and put it to their right ear. Therefore, it is easier to follow the story in the right ear.
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Lateralization of brain support for selective attention. On the left, focus on the left ear, on the right, naturally, on the right. It can be seen that different zones are activated. |
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Comparison of auditory and visual selective attention. In the task of left-sided auditory selective attention compared to visual attention during dichotic listening and simultaneous visual presentation of various texts, activation of the auditory cortex of the opposite hemisphere is also determined, which, as in the previous figure, reflects the selective tuning of the auditory cortex, independent of the type and complexity of the presented incentives. The process of suppressing the processing of irrelevant but significant visual stimuli during auditory attention causes pronounced activation of the visual cortex (occipital). |
It has been shown that auditory selective attention during binaural stimulation selectively activates areas of the temporal cortex specific to the auditory presentation of signals. These results are consistent with global data, confirming that the severity of this hemispheric lateralization also depends on the direction of attention. Our data indicate that this lateralization (one-sidedness) effect is concentrated in the primary auditory cortex, with selective attention to lateralized sounds increasing the activity of the auditory cortex predominantly in the primary auditory areas contralateral to the direction of stimulus delivery. That is, the auditory cortex is selectively tuned in accordance with the direction of attention, which is usually not detected by extracranial recording of electrical or magnetic activity of the brain. It is most likely that the hemispheric lateralization of activation of the auditory cortex that occurs, associated with spatially focused auditory attention, is caused by the preparatory tuning to attention of the left and right auditory cortex in accordance with the direction of attention, preceding the presentation of stimuli and occurring during the focusing of spatial attention. The prefrontal cortex appears to be involved in the control of attention because... in a number of studies, an increase in local cerebral blood flow and an increase in electrical activity was revealed. In our studies, increased prefrontal activity, especially in its dorsolateral region, is associated with the control of attention adjustment in the right and left auditory cortex, and the greater severity of activation in the frontal region during auditory compared to visual selective attention is most likely caused by a greater cognitive effort to perform auditory discrimination when attention had to be directed to one of two competing streams of stimuli, whereas performance in a visual attention task did not require intramodal selective attention. Thus, it was shown that the auditory cortex is selectively adjusted in accordance with the direction of attention. This tuning is controlled by the prefrontal executive mechanism, as evidenced by increased prefrontal activity during auditory selective attention.
What will happen if there is also a third text on the monitor, and you need to follow the auditory or the text on the monitor. We mentioned zones being activated to avoid doing something. Remember the famous “don’t think about the white monkey.” It turned out that if three stories are presented simultaneously: one in one ear, one in the other and one on the monitor, and asked to follow one (selective attention), then the activations that appear are not so easy to explain. It would seem that when paying attention to a visually presented story, the occipital (visual) parts of the cortex should be more activated, and when paying attention to a story presented to the ear, the temporal (auditory) cortex. No! During auditory attention, the cuneus and precuneus regions, that is, the associative visual cortex, are activated. Why? We still cannot answer for sure, but it seems very likely that significant and adequate, visually presented information is still analyzed by the brain and it passes through various structures, is compared with the contents of memory and returns back to the wedge region with the verdict: “Yes, this is meaningful.” valuable and meaningful information, and it means such and such.” But the task is different, this information is not only unnecessary, on the contrary, it is harmful, it interferes. And the observed activation reflects work in the “abnormal” mode, when “you can’t think about a white monkey.”
Another PET study that has access to the clinic. There is such a thing as anxiety. In general, from the name you can understand what it is. Each person is characterized at some point by a certain level of it, determined using a special and fairly simple questionnaire. The respondents can be roughly divided into three groups: high level, medium and low. What brain structures determine this level? It turned out that not just one structure, but a whole set. It is their coordinated state that determines the level of anxiety. In this case, it would be logical to assume that the higher the anxiety, the greater (or less) the activation of the structure. It turned out that everything was more complicated and interesting. Indeed, in one area, the level of activation is linearly correlated with the level of anxiety. But in the parahippocampal gyrus on the left, activation is minimal at an average level of anxiety, and when it increases or decreases, it increases. Thus, there is a system of a large number of structures, with each link playing its own special role.
Separately, I would like to say about the method of electrical stimulation for restoring vision and hearing. This is seemingly impossible with almost complete atrophy of the optic or auditory nerve - after a series of stimulations a person begins to see or hear. The theoretical substantiation of this phenomenon is still far from being fully understood, however, it has been shown that when electrical stimulation of the eye occurs, complex changes occur in the electrical activity of the entire brain, that is, complex compensatory processes are activated, and various biologically active substances are released that sharply stimulate the restoration of damaged nerves.
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Dynamics of visual fields during the course of treatment. Expansion of visual fields after a course of pulsed modulating electrical effects on the afferent inputs of the visual system. |
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Electroencephalogram power spectral mapping before (A) and after (B) treatment. The appearance of a regular alpha rhythm in the posterior parts of the brain in a patient with positive clinical dynamics of visual functions. |
Here I want to talk about a treatment method that has a fantastic name: brain transplant. This operation was performed for the first time in our country at ICH. Its essence, schematically, is that a section of the brain of a human embryo is transplanted into the brain and begins to produce substances, the deficiency of which leads to a disease, for example Parkinson's disease. This foreign piece of the brain can take root because there is no rejection reaction in the brain. However, it turned out that not only such a targeted brain transplant, when foreign cells are taken from certain structures of the brain of an embryo (obtained through a legal abortion) and introduced into certain structures of the recipient’s brain, has a therapeutic effect. If you “simply” take and plant the nervous tissue of an embryo into the abdominal wall, it, of course, will not take root, but the active substances contained in it have an extremely stimulating effect on the human body, and such treatment helps with epilepsy, coma, etc.
This task is due to the fact that a person's brain is located in his body. It is impossible to understand its work without considering the richness of the interaction of brain systems with various systems of the whole organism. Sometimes this is obvious: the release of adrenaline into the blood forces the brain to switch to a new mode of operation. A healthy mind in a healthy body is all about the interaction between body and brain. However, not everything here is clear. This interaction is certainly important to explore.
Today we can say that much is known about how one nerve cell works, many white spots are saturated with meaning on the brain map, and areas responsible for many mental functions have been identified. But between the cell and the brain region there is another, very important level - a collection of nerve cells, an ensemble of neurons. There is still a lot of uncertainty here. Using PET, we can trace which areas of the brain are “switched on” when performing certain tasks, but what happens inside these areas, what signals nerve cells send to each other, in what sequence, how they interact with each other, we’ll talk about this for now we know little. Although there is some progress in this direction. Here, micromapping made it possible to decipher what physiological processes occur in the inferior posterior parts of the frontal lobe, according to PET data, associated with the provision of semantics.
Previously, it was believed that the brain is divided into clearly demarcated areas, each of which is “responsible” for its own function - this is the zone of flexion of the little finger, and this is the zone of love for parents. These conclusions were based on simple observations: if a given area is damaged, then the function associated with it is also impaired. Over time, it became clear that everything is more complicated: neurons within different zones interact with each other in a very complex way, and it is impossible to carry out a clear “link” of a function to a brain area everywhere in terms of ensuring higher functions. We can only say that this area is related to speech, memory, and emotions. But to say that this neural ensemble of the brain (not a piece, but a network, distributed), and only it is responsible for the perception of letters, and this and that happens in it (definitely at the cellular level), and this one - words and sentences, is a task for the future .
The brain's provision of higher types of activity is similar to the flash of fireworks: at first we see a lot of lights, and then they begin to go out and light up again, winking at each other, some pieces remain dark, others flash. In the same way, an excitation signal is sent to a certain area of the brain, but the activity of the nerve cells inside it is subject to its own special rhythms, its own hierarchy. Due to these features, the destruction of some nerve cells may be an irreparable loss for the brain, while others may well be replaced by neighboring, “relearned” neurons. Each neuron must be considered within the entire cluster of nerve cells. Now the main task is to decipher the nervous code, that is, to understand how exactly higher functions are ensured. Most likely, this can be done through the study of cooperative effects in the brain and the interaction of its elements. The study of how individual neurons are combined into a structure, and the structure into a system and into the whole brain. This is the main task of the next century.
Laboratory functional states, which is headed by professor, laureate of the USSR State Prize V.A. Ilyukhina, is conducting developments in the field of neurophysiology of functional states of the brain. What it is? Everyone knows that the same influence, the same phrase is sometimes perceived in diametrically opposite ways by a person, depending on what is called the current functional state of the brain and body. This is similar to how the same note played from an organ has a different timbre depending on the register. Our brain and body are a complex multi-register system, where the role of the register is played by the state. In practice, we can say that the entire range of relationships between a person and the environment is largely determined by his functional state. This also applies to whether a “breakdown” is possible for a human operator at the control panel of a complex machine and the characteristics of the patient’s reaction to the medicine taken.
The task of the laboratory is to study functional states, what parameters they are determined by, how these parameters and the states themselves depend on the state of the body’s regulatory systems, how external and internal influences change states, sometimes causing disease, and how, in turn, the states of the brain and the body influence on the course of the disease and the effect medicines. It is shown that, like the reaction of the whole organism, the reactions of individual structures are modulated and depend on their state or, in the author’s terminology, on the level of relatively stable functioning (LSF). Based on these studies, ideas about the hierarchical principle of organization of brain systems and the role of infraslow processes as controlling the state of brain structures were formulated. It was found that the spatial distribution of OCSF on large areas brain and maintaining the relative stability of the brain state is due to the reciprocal balancing of the levels of relatively stable functioning of the zones of brain structures. This phenomenon works in such a way as to preserve the current state of the structure and a number of functionally related structures without significant changes, with the possibility of local changes in individual zones. In quantitative terms, the UOSF is determined by the sign, magnitude, and time of stability of the values of one of the types of ultra-slow physiological processes - the stable potential a of the millivolt range (omega potential a). In the conditions of long-term studies of many days and many months, it was found that the UOSF determines the amplitude-time characteristics of spontaneous multicellular impulse activity of neurons (impulse flow power), the type of ESCoG or ECoG, the amplitude-time characteristics of infraslow oscillations of the neuron potential in the range from 0.05 to 0 .5 oscillations per second (zeta, tau, epsilon waves), recorded simultaneously in the same areas of the brain structures. Spontaneous or induced changes in the state and physiological activity of areas of brain formations were reflected in the variability of different types of neurodynamics, which made it possible to observe complex spatio-temporal transformations occurring in parallel with different speeds neurophysiological processes, their subordination and relative independence, that is, to actually observe the dynamic work of this complex hierarchical system.
When performing emergency stereotypical types of activity (activation of attention, readiness for action, mobilization of short-term memory), the brain systems that support them are formed from potentially physiologically active links, i.e. ready to demonstrate this activity under specific conditions. At the same time, depending on the structure of activity, the physiological activity of the system units unfolds in a certain time sequence with the possible appearance of a reaction first in the dynamics of the impulse activity of neurons and the early phases of evoked potentials (EPs). Further, delayed in time (latent period - tens and hundreds of msec), changes in the late components of EP, weak in intensity (tens of μV amplitude) of ultra-slow physiological processes of the second range (CNV, typical phasic changes of zeta waves) can occur. It was found that the links in the system for providing emergency stereotypical activities retain physiological activity until their current state changes due to exogenous or endogenous influence (USF). It should be emphasized that a change in the UOSF zones of brain structures under these conditions entails the disappearance of the physiological activity of some units and, conversely, the manifestation of the physiological activity of others.
The reciprocity of changes in different zones and the redistribution of their activation appears to be one of the basic properties of the brain, determining its stability and richness of capabilities and protective functions. This was especially evident in studies of the brain support of emotions conducted under the leadership of N.P. Bekhtereva in the eighties. It was found that in an emotionally balanced person, during the development of any emotion, certain shifts in ultra-slow physiological processes, determined by the magnitude and sign of omega potential a in some structures, are usually accompanied by changes of this indicator of opposite sign in other structures. This mechanism prevents the excessive development of any emotion, keeps a person emotionally balanced and balanced. When it is violated, severe emotional disorders develop precisely because the mechanism that makes it possible to restrain the excessive development of a certain emotion does not work. In studies of impulse activity (Medvedev, Krol), it was shown that even when performing extremely monotonous activities, in an attempt to completely stabilize the functioning of the brain, endogenous spontaneous rearrangements occur in the functioning of its structures. In other words, even when performing monotonous stereotypical mental activity, the system that supports it is continuously reorganized. Thus, we can say that in order to complete a task, a temporary work collective is formed, which changes all the time, and all its members, firstly, are trained to perform various tasks, and, secondly, regularly have the opportunity to take a break.
By taking into account the characteristics of the conditions of the brain and body, one can correctly choose between alternative treatment paths. The definition of a person’s adaptive capabilities is interesting: one can predict how stable a given individual will be under any influence or stress. It turned out that some, even young people, have already exhausted their adaptive capabilities and even moderate stress can cause a pathological reaction in them. It is possible to identify such people and provide them with timely corrective treatment.
The laboratory of neuroimmunology (Professor, Doctor of Medical Sciences I.D. Stolyarov) is engaged in the current task. It is now known that many nervous diseases are associated with improper functioning of the immune system. Immunoregulation disorders often lead to severe brain diseases. The nervous and immune systems carry out their protective functions in close interaction. They are united by common principles of organization, common intermediary molecules, and regulatory functions that are significant for the organism as a whole. The discovered patterns of the neuroimmune reaction to a foreign stimulus made it possible to use the data obtained for the diagnosis and treatment of a number of brain diseases. Clinicians have previously noted that, on the one hand, the destruction or underdevelopment of brain structures is accompanied by immunodeficiency, on the other hand, primary and secondary immunodeficiencies lead to functional disorders or diseases of the brain. In the development of many chronic diseases of the nervous system, infectious viral and further immunopathological mechanisms are of much greater importance than expected.
Multiple sclerosis is a severe chronic disease of the brain and spinal cord that affects relatively young people between 20 and 40 years old. The ambiguity of many questions regarding the occurrence and mechanisms of development of the disease, the difficulties of diagnosing early stages development, a variety of clinical variants of the course with rapid disability, and the lack of effective treatment methods have brought the study of multiple sclerosis to the circle of the most pressing problems of modern medicine. The Laboratory of Neuroimmunology of the Institute of Human Brain of the Russian Academy of Sciences has developed a new approach that allows, simultaneously with the use of specific immunological methods for assessing damage to cells of the central nervous system, the use of magnetic resonance and positron emission tomography to visualize the pathological process. The fundamental novelty is that this approach allows simultaneous assessment of both systemic autoimmune disorders in multiple sclerosis and local functional and morphological changes in the central nervous system. A comprehensive neuroimmunological, instrumental, and clinical examination of patients with multiple sclerosis made it possible to establish the important role of lesions of the cortex and subcortical structures in the mechanisms of development of this disease.
If previously the diagnosis of “multiple sclerosis” sounded like a death sentence, now the use of modern genetically engineered immunocorrective drugs can significantly improve the patient’s quality of life and maintain ability to work for a long time. To increase the effectiveness of the use of these drugs, the laboratory of neuroimmunology developed immunological criteria for assessing the effectiveness of immunocorrective and genetically engineered drugs in patients with multiple sclerosis.
Immunological mechanisms play a role not only in multiple sclerosis. The destruction of part of the brain tissue during strokes also causes immunological changes. Moreover, infectious complications caused by secondary immunodeficiency are one of the most severe, often ending in the death of the patient from these stroke complications. Research by employees of the laboratory of neuroimmunology has shown that the side of the brain lesion during cerebral ischemia in experiments and clinics can determine the peculiarity of changes in immunological reactivity. And as part of the comprehensive development of new methods of treatment and rehabilitation of post-stroke patients, it has been proven for the first time that electrical stimulation of cerebral cortex structures in subacute ischemic strokes, used by current IMC employees since 1972, is accompanied by normalization of immunological parameters. Timely immunocorrective therapy can significantly reduce the severity of complications or avoid them altogether. Not long ago, the head of this laboratory joined the board of the European Committee for the Research and Treatment of Multiple Sclerosis.
The second half of the nineteenth and most of the twentieth centuries had the motto of victory over nature. And indeed, man celebrated one victory after another over nature. He conquered rivers and conquered diseases. But it turned out that these were not subjugations of nature, but a tactical retreat to regroup its forces. Now we can give many examples of, so to speak, successful counterattacks of nature. This includes AIDS, hepatitis C, and much more. Nature responded in particular by the fact that now the problems created by man himself, the so-called man-made, have become especially acute. We live in strong magnetic fields (trams, subways, power lines, etc.), in the light of gas lamps - blinking 50 hertz, we look at the computer display for hours - the same hertz, we speak in mobile phone and further. . . All this is far from indifferent to a person, and increased fatigue is not the worst thing. These studies are carried out by a laboratory under the direction of Doctor of Medical Sciences. E.B.Lyskova.
We can no longer live without a telephone, a television, without electric current and other achievements of civilization. Therefore, research is needed on how to coexist peacefully with them. For example, it is well known that flashing lights can even cause an epileptic seizure. However, it is amazing how the simplest measures can dramatically reduce the danger. Counteraction - close one eye and generalization will not occur. To dramatically reduce the “damaging effect” of a radiotelephone - by the way, it has not yet been definitely proven - you can simply change the design so as to point the antenna down, and the brain will not be irradiated. For example, the laboratory has shown that exposure to an alternating magnetic field has a negative effect on learning. However, not any field, but one with a certain frequency and amplitude. Therefore, it is these parameters that you should try to avoid. A monitor with a refresh rate of 50-60 Hz is harmful, especially if you sit close to it. However, if the frequency is set to at least 80 Hz, the harmful effect will sharply decrease. We have now learned to identify people at risk - those who are hypersensitive to man-made impacts. Thus explaining seemingly causeless nervous disorders. This work is carried out within the framework of very close international cooperation.
Brain research is significantly hampered by the difficulty of direct access to it.
In a conventional abdominal operation, the skin is incised, and almost immediately the surgeon has access to the organ of interest. At the end of the operation, the skin is sutured and after two to three weeks only a scar remains. The brain is covered by the skull, and to access it the surgeon has to perform trepanation of the skull, that is, destroy some part of it, sometimes not a small one. But this is not the worst. If the lesion is located deep in the brain, then it is necessary to reach it by moving apart (and sometimes destroying “along the way”) other areas of the brain. This dramatically increases the morbidity of the operation and sometimes makes it impossible, since this collateral damage can cause worse consequences than the disease itself.
This contradiction can be resolved using stereotactic technique. Stereotaxis is a high-tech medical technology that provides the possibility of low-traumatic, gentle, targeted access to the deep structures of the brain and dosed effects on them. Stereotaxis is in many ways the neurosurgery of the future; it is capable of replacing a number of “open” neurosurgical interventions with wide osteoplastic trepanations with low-traumatic, sparing effects.
Modern neurosurgery uses time-tested techniques for precise localization of lesions in the brain, and today this is primarily carried out using magnetic resonance imaging methods, the resolution of which covers the needs for determining the location surgical intervention. In typical conditions of a modern clinic http://hospital.ukr/neurosurgery, almost the entire range of neurosurgical care is performed, including the most modern methods of localizing the site of impact.
The essence of stereotaxis: to know very precisely where in the brain there is a structure (target) that needs to be influenced - coagulate, freeze, evacuate, stimulate, and through a small hole in the skull - about a centimeter - insert a thin instrument, about two millimeters in diameter, which often does not pierce, but rather pushes apart the brain tissue with minimal traumatic impact. At the end of this instrument there is an effector, which produces the necessary effect. In this case, it is still extremely important to accurately hit the target structure with the tool.
In developed countries, primarily in the USA, clinical stereotaxis has taken its rightful place in neurosurgery. There are currently about 300 stereotactic neurosurgeons in the United States who are members of the American Stereotactic Society. The basis of stereotaxis is mathematics and precision instruments that provide targeted immersion of subtle instruments into the brain. Important role Stereotaxis is played by modern methods and devices of introscopy, which allow you to “look” into the brain of a living person. As mentioned above, these are positron emission tomography, magnetic resonance imaging, computed x-ray tomography. “Stereotaxy is a measure of the methodological maturity of neurosurgery” - the opinion of the late neurosurgeon L.V. Abrakov. And finally, it is very important for the stereotactic method of treatment to know the role of individual nuclei, “points” in the human brain, understanding their interaction, i.e. knowledge of where and what exactly needs to be done in the brain to treat a particular disease.
Laboratory of Stereotactic Methods of the Institute of Human Brain of the Russian Academy of Sciences under the direction of Dr. med. USSR State Prize laureate A.D. Anichkov is the leading stereotactic center in Russia. Here the most modern direction of stereotaxis was born - computer stereotaxis with software and mathematics implemented on a computer (before these developments, stereotactic calculations were carried out by neurosurgeons during surgery, or the patient in a traumatic frame had to undergo introscopy (MRI or CT) immediately before the operation. ). Dozens of stereotactic devices have also been developed here, some of which have undergone clinical testing and have been used to solve the most complex problems of stereotactic guidance. Together with colleagues from the Elektropribor Central Research Institute, a computerized stereotactic system was created and for the first time in Russia is mass-produced, which is superior to similar foreign models in a number of key indicators. “Finally, the timid rays of civilization illuminated our dark caves,” - unknown author.
At our Institute, stereotaxis is used in the treatment of patients suffering from movement disorders (Parkinson's disease, Huntington's chorea, other hemihyperkinesis, etc.), epilepsy, indomitable pain (in particular phantom pain syndrome), and some mental disorders. In addition, stereotaxis can be and is used for precise diagnosis and treatment of certain brain tumors, treatment of hematomas, abscesses, and brain cysts. It is important to emphasize that stereotactic interventions (like all other neurosurgical interventions) are offered to the patient only if all possibilities of non-surgical (drug) treatment have been exhausted, and the disease itself poses a danger to the patient (or deprives him of his ability to work, desocializes him). Naturally, all operations are performed in the ICH clinic only with the consent of the patient and his relatives, after a consultation of specialists of various profiles.
We can talk about two types of stereotaxis. The first, non-functional, is used when there is some kind of organic damage deep in the brain. For example, a tumor. When you try to remove it using conventional technology, you will have to go through healthy structures that perform important functions, and the patient may be harmed, sometimes even incompatible with life. However, this tumor is clearly visible using modern intravision tools: magnetic resonance and positron emission tomographs. You can calculate its coordinates and destroy it, or, for example (another method developed in the IMC), introduce radioactive sources using a low-traumatic thin probe, which will burn out the tumor and disintegrate during the same time. Damage when passing through the brain tissue is minimal, only the tumor will be destroyed, sometimes of a very complex shape, very aggressive, and destroyed radically. We carried out a number of such operations several years ago, and there are still patients living for whom there was no hope with traditional methods of treatment.
The essence of this method is that we eliminate the “defect” that is clearly visible. The problem is how to get to it, which path to choose so as not to affect important areas, which adequate method of eliminating the “defect” to choose: implantation of sources, thermocoagulation or cryodestruction, but the essence is the same: we eliminate what we clearly see.
The situation is fundamentally different with “functional” stereotaxis, which is used in the treatment of a number of diseases described above. The cause of disease is often that one small group of cells, or several groups close or far apart, are not working properly. They either do not release the necessary substances or release too much of them. They can be pathologically excited and provoke healthy cells to “bad” activity. These bad cells must be found and either destroyed, isolated, or (which is very interesting) “re-educated” using electrical stimulation. The important thing is that the affected area cannot be seen here. We must calculate it, just as Le Verrier calculated the orbit of Neptune.
This is where fundamental knowledge about the principles of the brain, the interaction of its parts, and the functional role of each part of the brain is critically important. It is important to use the results of a new direction developed by a member of our team, the late Professor V.M. Smirnov - stereotactic neurology. This is aerobatics. However, it is precisely on this path that the possibility of treating many serious diseases, including mental ones, lies.
The results, including our research, have shown that almost any complex activity, and especially mental activity, is ensured in the brain by a complex system distributed in space and fundamentally variable in time, consisting of links of varying degrees of rigidity . It is clear that interfering with the operation of the system is much more difficult. However, now in a number of cases, which will be discussed below, we can do this.
There are nerve cells that are ready for their work from birth. These are, for example, neurons in the primary visual cortex. Others are brought up during ontogenesis and learn something. How does this happen? First, a large group of cells is involved in providing new activity. Then, as it is “stereotyped,” the territories are minimized and the number of neurons providing it is radically reduced. The remaining cells seem to forget what they knew how to do. But, as we were able to show, not forever. Even after this specialization, they are, in principle, able to take on some other tasks; they have not completely “forgot” how to work differently. Therefore, you can try to force them to take over the work of the lost nerve cells and replace them.
Neurons of the brain work like the crew of a ship: one is good at guiding the ship along its course, another at shooting, and a third at preparing food. But a gunner can be taught to cook borscht, and a cook can be trained to aim a gun. You just need to explain to them how it's done. In principle, this is a natural mechanism: if a brain injury occurs in a child, his nerve cells spontaneously “relearn.” In adults, special methods must be used to “retrain” cells.
This is the basis of the treatment method: with the help of point electrical or distributed magnetic stimulation, some nerve cells are trained to perform the work of others, which can no longer be restored. Most likely, electrical stimulation here sharply and nonspecifically activates a region of the brain, while increasing the level of its plasticity. Good results have already been obtained in this direction: for example, some patients with traumatic lesions of Broca's and Wernicke's areas, which are responsible for speech formation, were able to be taught to speak and understand speech again.
This was the re-education of neurons. But a number of brain diseases, in particular those leading to serious mental disorders, such as obsessive-compulsive syndrome (obsessive states), Gilles de la Tourette's disease, pathological aggressiveness, arise due to the hyperactivity of certain brain structures. Here, the task of stereotactic surgery is to eliminate this focus of excitation. This, in principle, is a “own” task for functional stereotaxis. Unlike the method of electrical stimulation, it is used when there is a “plus” phenomenon (pathological excitation, overproduction of a substance and associated hyperkinesis, emotional arousal, etc.) and it needs to be destroyed, and is not used when it is “minus” phenomena when, for example, plegia occurs due to hypoactivity of any part of the brain.
Let's look at an example that has now become a hot topic: surgical treatment for drug-related obsessive-compulsive disorder. One of the terrible properties of a drug is addiction to it, so addictive that the addict becomes dependent on it and cannot live without it. There are two types of addiction: physical and psychological. The first type of addiction is due to the integration of heroin into the energy consumption mechanism of the brain cell. The cell gets used to eating a lighter (but not effective) version and does not want to return to the old and effective one. Therefore, when you stop taking the drug, “withdrawal” occurs - abstinence, which is extremely painful and can even end in the death of the drug addict. However modern medicine I learned to deal with this relatively easily and painlessly; there are various, very effective ways to eliminate physical addiction, which are successfully used in many clinics. So, the drug addict is “laundered”. His body no longer needs drugs. But he remembers the wonderful feeling that he experienced when using them, and with every fiber of his soul he dreams of experiencing it again. This is not a whim, this is a serious mental illness: obsessive-compulsive syndrome - and it is impossible to resist this attraction. Reasonable arguments do not work on him. Unfortunately, the effectiveness of treatment for psychological dependence on drugs is still extremely low and ranges from 3 to 8 percent. Considering that the average lifespan of a heroin addict is four years, we can say that the patient is doomed. In this sense, heroin can be compared to a malignant tumor, and, as a rule, one can talk not about a cure, but about a period of survival, a delay in the terrible end.
Our clinic uses a surgical method to treat heroin-related obsessive-compulsive syndrome. The theoretical explanation of both the syndrome itself and the mechanism of action of the proposed treatment method cannot yet be considered completely complete, so below we will present one of the concepts that we consider the most probable. Naturally, in this article, intended for the general reader, it will be presented in a simplified form, for which I apologize to the specialists.
Pathological craving for drugs is caused by the imprinting of emotional memory of the feelings experienced after taking it. This emotional excitement is so strong that it overshadows almost everything. The entire life of a drug addict is subordinated to the idea of achieving the same state again. Like all psychological phenomena, this corresponds to certain neurophysiological processes. The most important system that provides emotions is the limbic system. Schematically, it can be depicted as a vicious circle consisting of various brain structures, and emotional phenomena correspond to a certain impulse (activation or deactivation) of neurons in these structures. According to the concept that we adhere to, an obsessive state manifests itself in the appearance of pathological hyperexcitation in this circle, which, circulating in a circle, through a positive feedback mechanism, reaches the level of saturation, suppresses any other emotions and becomes uncontrollable. (See above about balancing emotions.) This mechanism is the same for an obsessive state of any nature.This is the same reverberating excitation that determines the main essence of short-term memory. Only usually such arousals are extinguished during sleep, but an obsessive state is so strongly aroused and supported by some external stimuli that it is not. It continues to be active even after sleep, which is why it manifests itself as obsessive and constant. Naturally, the idea arises to break this vicious circle. Therefore, back in the sixties, structures of the limbic system were proposed as target structures for operations for obsessive-compulsive syndrome. In particular, the target we use in the treatment of drug addicts was proposed in 1962. However, the insufficient methodological level that existed at that time did not allow this operation to become widely used. The situation changed radically with the introduction of modern stereotaxis, developed, among other things, at our institute. It turned out to be possible, through a low-traumatic approach using a cryoprobe with an outer diameter of 2.6 mm, to freeze a small section of the cingulate gyrus between its anterior and middle sections and thereby cut this vicious circle. The operation itself is extremely low-traumatic, it’s like an injection into the brain. The chosen method of exposure - freezing - differs favorably from thermocoagulation and other tissue-destroying influences in that it leaves the walls of arteries and arterioles intact, thereby minimizing the risk of bleeding. As a rule, the patient already on the operating table says that he is no longer drawn to drugs. Why? Yes, because despite the fact that he remembers about drugs, this pathological hyperimpulsiveness no longer exists, and this memory is not emotionally colored. Yes. He remembers that he injected himself, but he doesn’t remember why it was so great. This emotional excitement that sweeps away everything in its path disappears, and what remains is just memory. It is interesting that specially conducted studies have shown that the personality profile does not change, except, perhaps, for the natural expansion of the emotional sphere. Naturally, he was only thinking about the drug, but now he noticed that there were also beautiful girls.
This is a possible mechanism for the stereotactic treatment of obsessive states of various natures. This includes phantom pain syndrome, during the treatment of which we discovered the disappearance of cravings for drugs (patients were forced to take drugs to relieve pain), and others.
Naturally, however, the operation remains an operation. It is always potentially dangerous, so we only go for it when all other methods of conservative treatment have been exhausted. Thus, the mechanisms of the therapeutic effect of psychosurgical operations aimed at turning off the structures of the limbic system can be explained by the partial interruption of pathological impulses that circulate along the nerve pathways. This impulse, which is a consequence of hyperactivity (excessive activity) of different (for different diseases) areas of the brain, is a mechanism common to a number of chronic diseases of the nervous system, such as epilepsy, obsessive-compulsive disorder. These paths must be found and turned off as gently as possible. Stereotactic psychosurgical interventions (many hundreds of them have been carried out and most of them in the USA) are a modern method of treating patients suffering from certain mental disorders (primarily OCD - obsessive-compulsive disorders, i.e. obsessive states), for which non-surgical methods have proven ineffective treatment.
At the cellular level, all brain work is associated with chemical transformations of various substances, so the results obtained in the laboratory of molecular neurobiology, headed by Professor S.A. Dambinova, are important to us. The laboratory explores the neurochemical basis of the functional integrity of the brain and body using modern molecular approaches. In other words, the laboratory studies molecular processes that are associated with the transformation of simple chemical signals into complex integrative ones that ensure the functions of the whole organism. Let's look at how this happens.
For example, in parallel with physiological studies of brain activity in movement disorders, the metabolism of neurotransmitters (substances that transmit information from neuron a to neuron y) was studied: glutamate, GABA, dopamine and serotonin. It was found that their clinical dynamics in patients with parkinsonism stabilized with the positive effect of therapeutic electrical stimulation (TES). However, compensation for dopamine and serotonin deficiency using pharmaceutical therapy did not produce the expected effect in patients with parkinsonism. Only after low molecular weight peptide fractions were first discovered, which appeared immediately after LES and accompanied an improvement in the clinical condition of patients - a decrease in tremor, rigidity and the appearance of positive emotional reactions, their fundamental role in the neurochemistry of movement became clear.
With further study of these peptide fractions, peptides of the tachykinin group or peptides of the substance P group were isolated and characterized. The introduction of these peptides into the cerebrospinal fluid of the patient using the autohemolytic cerebrospinal fluid transfusion method developed by us together with neurosurgeons repeated the therapeutic effect of LES and the simultaneous stimulation of positive emotions in patients with parkinsonism.
It turned out that these peptides regulate anticholinergic and dopaminergic pathways and have properties that inhibit prolactin hyperfunction. The long-term effects of LES are associated, first of all, with the normalization and compensation of molecular deficits in the neurotransmitter-neuropeptide-neurohormones system in the organization of motor and closely related emotional reactions. It is especially interesting that similar patterns were discovered later in patients with heroin addiction, who showed significant changes in the content of dopamine and serotonin in biological fluids. Therefore, the creation of new pharmacological agents based on the discovered neuropeptides is a very promising direction in the treatment of parkinsonism, drug addiction and depressive conditions.
In order to understand the specific mechanisms underlying the motor and emotional functions of the brain, it was necessary to study the next intercellular neuroreceptor level in the hierarchy of signal transmission.
Neuroreceptors are macromolecules on the membrane of a neuron, the mosaic of which determines the specificity of its functions, the functions of a zone or brain structure. The polyreceptor structure of the brain reflects the multifunctionality of systems that support diverse activities of the same cells and zones in the nervous tissue.
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Localization of mu- and delta opiate receptors in brain structures. |
Administration of opiates leads to the activation of dopaminergic neurons and the release of dopamine in the ventral tegmental area and nucleus accumbens. This effect of opiates is mediated through inhibition of GABAergic neuron activity. |
Therefore, in the laboratory, special attention is paid to studying the structure and functions of neuroreceptors for glutamate, opiates and their metabolites, which are involved in the development of cerebral ischemia and convulsive reactions and the emergence of mental and physical dependence on psychotropic drugs. It is assumed that it is these excitatory brain receptors that are primarily involved in the interaction and reorganization of systems that provide complex functions of the human brain associated with movement and emotional behavior.
How neuroreceptors work in a cell, how they interact within the system and their intersystem connections, what their properties are in health and disease, is the subject of in-depth neurochemical research.
Based on many years of research in the laboratory, it was possible to establish that glutamate and opiate receptors change their functions in brain tissue during hyperexcitation and are capable of changing the state of the entire organism when stimulated by pharmacological agonists and antagonists. The study of the molecular properties of these receptors revealed their similarity in the dynamics of reorganization of various functions in the “brain-body” system associated with impaired metabolism of receptor metabolites (glutamate, aspartate, opiates) in biological fluids. Let us give the following examples of the participation of opiate receptors in the mechanisms of organizing emotional experiences using an experimental model of heroin self-administration in rats. The following patterns were identified:
It has been established that the rewarding effects of drugs (heroin and morphine) are mediated through opiate receptors located in the mesolimbic system and regulating an increase in the content of dopamine in the intercellular space.
- it has been shown that chronic activation of opiate receptors by heroin leads to stimulation of additional receptors, which require new portions of the drug to perform their functions and are involved in the formation of an irresistible craving for heroin consumption.
- it was revealed that at the initial stage there is an increase in the expression of opiate receptor genes and a significant stimulation of brain activity - activation of behavioral reactions, stimulation of emotional experiences (lack of fear, pain, euphoria).
On the other hand, long-term and systematic consumption of heroin disrupts the stability of the brain-body system and gradually leads to the destruction of excess and then necessary amounts of neuroreceptors, which reflect the restructuring of the system of organizing brain functions and the degree of destructive processes of nerve cells in its structures. The body reacts to these disorders by producing “autoantibodies” to specific fragments of opiate receptors, as “witnesses” to “foreign” antigens of the nervous tissue. It turned out that the appearance and amount of autoantibodies to individual fragments of opiate receptors correlates with the severity of drug addiction symptoms. Therefore, by analyzing blood for the content of autoantibodies to neuroreceptors in the brain, it became possible to determine the functional state of the brain and body of animals and humans, and a diagnostic kit “Drug Test” was created, which allows one to objectively assess the degree of drug addiction and monitor the effectiveness of treatment for drug addicts.
Similar patterns were identified when studying the molecular mechanisms of the development of epilepsy and ischemic brain lesions, which made it possible to develop original and objective indicators for assessing brain function (PA test and CIS test) for early laboratory diagnosis of paroxysmal activity and cerebral ischemia in humans. These laboratory diagnostic methods are already used in some scientific and medical institutions in the country and abroad.
Thus, fundamental research in the field of neurochemistry is already providing practical results for medicine. In this case, neurochemistry acts as a basic molecular “language” that makes it possible to decipher complex integrative processes in the brain and body in pathological conditions in humans.
It should be noted that the Laboratory of Molecular Neurobiology is one of the leading neurochemical centers in Russia and has its own research groups in Italy and the USA. Over the past year, I, like probably many others, have been asked about the greatest achievements of the past century and the prospects for the century to come. One can argue about specific achievements, but in general we can say that the twentieth century was the century of technology and physics. However, recent years have clearly shown that the next century will be the century of biology, and we can expect that understanding the mechanisms of brain activity and, above all, code nervous activity will occupy priority positions. What I have said here briefly about the institute and its laboratories is set out much more fully in the articles, a list of which is attached.
