What connects the brain and consciousness. Human consciousness and brain

About the author: Ivanitsky Alexey Mikhailovich, Corresponding Member of the Russian Academy of Sciences, Professor, Doctor of Medical Sciences. Head of the Laboratory of Human Higher Nervous Activity, Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences.
05.2005. No. 11 "IN THE WORLD OF SCIENCE"

Emergence of consciousness- one of greatest secrets nature, the solution of which physicists and writers, philosophers and clergy, doctors and psychologists have been struggling for thousands of years. In recent years, knowledge about how the brain works has accumulated very quickly. Therefore, science has come close to solving the riddle of consciousness. What is it like a modern view of the relationship between consciousness and processes occurring in the brain?

Human consciousness- is, in essence, his life, consisting of an endless change of impressions, thoughts and memories. The mystery of our brain is multifaceted and affects the interests of many sciences that study the mysteries of existence. One of the main questions is How is consciousness connected to the brain?. This problem is at the intersection of natural science and humanities, since consciousness arises on the basis of processes occurring in the brain, but its content is largely determined by social experience. The solution to this puzzle could build a bridge between the two main types of scientific knowledge and contribute to the creation of a unified picture of the universe that organically includes man and his spiritual world. This is probably the highest goal of science, the achievement of which is necessary to satisfy the inherent human desire for comprehensive knowledge. But great practical significance this problem for medicine, education, organization of work and leisure.

Interest in the relationship between consciousness and the brain arose a long time ago. For Russian physiology, starting from the time of I.M. Sechenov and I.P. Pavlova, he is to a certain extent traditional. However, for a long time the solution to such a complex problem was considered a matter of the distant future. The understanding that the study of the problem of consciousness is an urgent task of today came to physiologists relatively recently: the rapid progress of brain science has brought this topic on the front pages of neuroscience journals. There even arose, in the figurative expression of the English scientist John Taylor, a “race for consciousness.” The breakthrough in this field was largely due to the advent of “living brain imaging” techniques such as positron emission tomography, functional magnetic resonance, and multichannel recording of the brain’s electric and magnetic fields. The latest devices have made it possible to see on the display screen which zones are activated when performing various tasks that require mental effort, as well as to accurately determine the location of lesions in diseases of the nervous system. Scientists have gained the ability to obtain corresponding images in the form of colorful maps of the brain.

From a philosophical point of view, one may wonder how legitimate it is at all to try to explain by the movement of nerve impulses what we perceive as color or sound. Feeling- a purely personal feeling, the “inner theater” of each of us, and the task of brain science is to understand what nervous processes lead to the emergence of a subjective image. At the same time, the mystery of the human psyche is not unique in its methodological complexity and stands among other mysteries of nature. Essentially, the emergence of a new quality occurs at each stage of fundamental complication of natural processes. American scientists F. Crick and K. Koch consider the origin of life as a result of the action of DNA chains and enzyme proteins to be an example of a qualitative transition comparable in complexity to the emergence of consciousness. The properties inherent in living objects do not follow directly from the physicochemical properties of each of these molecules. This example seems especially convincing in the mouth of F. Crick, one of the discoverers of the genetic code.

The experience of scientific knowledge shows that a complex phenomenon, as a rule, does not arise out of nothing, but develops in the process of evolution from simpler forms. The same fully applies to subjective experiences. They progress from elementary manifestations, such as sensations and emotions, to higher-order consciousness associated with abstract thinking and speech. Based on these considerations, there are several approaches to the study of consciousness, which, however, do not exclude, but complement each other each other, explaining phenomena of varying degrees of complexity. At the same time, some basic principles of the organization of nervous processes, discovered in the early stages of the evolution of the psyche, gradually acquire more complex forms to ensure their highest manifestations.

Return of excitation and mechanism of sensations

The first approach to understanding the principles of the nature of the psyche is based on the idea that subjective experience arises as a result of a certain organization of processes occurring in the brain comparison in cortical areas of new information with that extracted from memory . Information about external events is, as it were, projected onto the individual experience of the subject. This occurs as a result of the circular movement of excitation, which, after additional processing in other brain structures, returns to the places of initial projections. We first put forward such a hypothesis in the 1970s. as a result of research into the brain mechanisms of sensation. Currently, it is shared by many specialists.

As already mentioned, this hypothesis was based on our studies of the mechanism of sensations. We studied evoked potentials (VP) of the brain, that is, its electrical reaction to a newly received signal. The EP is a complex oscillation consisting of a number of sequential components, and it was necessary to understand what information processes of the brain they reflect. Data analysis led to the conclusion that early waves of EP are associated with the receipt of impulses into the cortex along sensory pathways from the sense organs . They reflect the physical parameters of the stimulus. Late waves caused by the transfer of excitation from motivational centers characterize the significance of the signal . Next, the question arose of how these information processes relate to subjective experience. I turned to the director of the Institute of Psychology of the Russian Academy of Sciences - in those years this post was held by Corresponding Member of the USSR Academy of Sciences B.F. Lomov. His answer was unexpected and interesting. He said that in psychology there is a theory that is close in its provisions to our views. It was about the theory of signal detection, which considers perception as the result of the interaction of sensory and motivational factors , which are called, respectively, sensory sensitivity indicator and decision criterion . It is interesting that this approach was borrowed by psychology from technology, in particular, from the principle of radar design, consisting of a sensitive receiver and a signal identification system.

In the course of further research, it was necessary to compare two concepts in one experiment: physiological and psychological. The difficulty was that the detection theory works in the region of weak signals close to the threshold, since calculation of the corresponding perception indices is based on the ratio of correct and erroneous reactions . At the same time, recording EP with its early waves requires fairly intense stimuli. It was decided to use not absolute, but differential threshold. The participant in the experiment had to distinguish the intensity of two stimuli of similar strength (visual in one series, cutaneous in the other), while brain EPs to the presented stimuli were recorded. To obtain quantitative parameters of sensations, methods of signal detection theory were used to calculate the two mentioned indicators. Then a correlation was obtained between physiological and psychological indicators, with the results were, in principle, similar for vision and skin sense . As expected it was the correspondence of the early waves of EPs with the sensory factor of psychophysics was established, and the later ones - with the decision criterion . It turned out to be somewhat unexpected and therefore most interesting relationship between intermediate waves of EP projection cortex (where impulses from the senses are received) with both indices of perception, that is, both with an indicator of sensory sensitivity and with a decision criterion. This double correlation reflects the synthesis of information about the physical and signal properties of the stimulus on the neurons of the projection cortex. These waves appeared in the EP 150-180 ms after the stimulus.
It is fundamentally important that this time coincided quite accurately with the speed at which sensations arose , obtained earlier during psychophysical experiments.

Back in the 20-30s. last century it was found that sensations appear only 100-150 ms after the presentation of the stimulus . In this case, methods were used based mainly on the phenomenon " reverse masking ". Its essence is this: if after one weak stimulus a second, stronger one follows after a short interval, the first is not perceived . By gradually increasing the time interval between both signals, it is possible to calculate the moment when the masking effect disappears, since the sensation of the first stimulus has time to form. It was found that the sensation appears approximately 150 ms after the stimulus. The most reliable data, however, were obtained when direct stimulation of the cortex with a short magnetic pulse, which was applied to the scalp directly above the corresponding area of ​​the cerebral cortex, was used as a masking signal - the results obtained practically coincided with those given above. It is important that the magnetic pulse caused a masking effect only if it affected the occipital cortex, which projects for visual stimuli, then exists only where the above-described double correlation of EP waves with perception indicators was observed . An interval of 150 ms is called " psychological refractory period ", and mental experience cannot be shorter than it. It is interesting to compare the given indicators with physiological data on the duration of information processing for a single stimulus in the visual cortex, which is about 200 ms (I.A. Sheelev).

Based on data on the physiological mechanism of evoked potential waves and their connection with parts of the brain, we described the process that ensures the synthesis of information. It includes circular movement of excitation across parts of the brain . From the projection cortex, which receives signals from the sensory organs, excitation enters the associative cortex (inferotemporal for visual stimuli), where information is compared with a standard and recognized. Then the excitation moves to the entorhinal cortex, located on the inner surface of the temporal lobe of the hemispheres and related to memory. There the significance of the signal is determined, its relationship to one or another need of the body. Then the excitation impulses move to the motivational centers of the diencephalon, from where they return again through a system of diffuse projections to the cortex, including the primary projection zones. After 100 ms, connections also arise between the projection and frontal cortex. This cycle, which lasts about 150 ms, is called " circle of sensations". Its essence is that it provides comparison of the sensory signal with information extracted from memory , including data on the significance of the information received, which presumably underlies transition of a physiological process to the mental level , subjective experience . As a result, the resulting sensation not only accurately conveys the physical characteristics of the stimulus, but is also emotionally charged. The above concept is called the information synthesis hypothesis.

In subsequent years, it was confirmed by the results of many studies, including data on the topography of the parts of the brain included in the “circle of sensations”, and the use of the idea itself return of excitation to explain the mechanisms of consciousness. Among the most significant are the works of Nobel laureate J. Edelman, who used the term " re-entry(re-entering)", denoting not feedback, which is usually understood as a correction signal, but receipt of additional information obtained as a result of a survey of brain structures related to memory function and motivation.

In addition to information synthesis, the return of excitation along diffuse projections also ensures the integration of individual stimulus features into a single image. Research in recent years has shown that important role plays the rhythm of the electroencephalogram (EEG) with a frequency of about 40 Hz. Exactly synchronization of brain biopotentials at a certain rhythm creates conditions for combining neural networks into a single system , which is necessary to maintain consciousness.

Sensation refers to fairly simple mental phenomena, which some scientists attribute to the so-called primary consciousness , which also includes emotions, to the study of which P.V. made an outstanding contribution. Simonov. He was the first to propose a formula according to which the strength of emotion E is proportional to the need P, multiplied by the difference between the information available to the individual and what he needs to satisfy this need :

E = P (Inf. available - Inf. required)

From this formula it follows that emotions, like sensations, arise as a result of comparison of two information flows . Thus, there is a certain universal pattern at work here.

Of interest is the question of how, in the course of evolution, a system for returning excitation and comparing two information flows could arise. In accordance with the concept of N. Humphrey, the psychic appeared as a result of the action of branches of motor fibers extending from the cortex to sensitive paths heading to the cortex, which made it possible directional regulation of information arriving to the cortex . In simpler systems, such a process could occur on the periphery, but gradually developed intracortical methods of filtering by executive centers the most significant information for determining behavior , which could act in the absence of motor commands. N. Humphrey called such a mechanism " sensual loop "(sentient loop), which is even terminologically close to our “circle of sensations”.
Speaking about the mechanisms of sensations, it is appropriate to recall the words once spoken by I. Goethe: “If I did not carry the whole world within me, I would be blind with healthy eyes.”

Consciousness and speech. Thinking. Frontal cortex

More complex psychic phenomena, primarily associated with the appearance of speech, are classified as higher-order consciousness. According to P.V. Simonov, it arose as a result of communication between people. This process is also associated with the specialization of the hemispheres. An interesting opinion was expressed by M. Corballis: he believes that speech developed from the need to convey fairly complex information, first at the level of exchanging gestures. Only later, when the forelimbs were occupied with tools, hand movements began to be combined with vocal signals, which gradually turned into the main means of communication. Since the vocal centers in many animals are located on the left, cortical speech centers also arose in the left hemisphere. At the same time, the functions of Broca's area - the motor center of speech, located in a person's left frontal region - also changed. Monkeys have similar cortical zones in both hemispheres, but their function is somewhat different: there are “mirror neurons” that control actions that repeat the movements of another individual (“monkeying”). It's interesting that in young children, speech motor centers are also bilateral , and damage to one of them does not lead to loss of speech, as happens in adults. Speaking about the mechanisms of higher mental functions, especially thinking, it is necessary to say about the works of N.P. Bekhtereva and her school.

The last years of the last century, declared the “decade of the brain,” were marked by the rapid accumulation of knowledge about the principles of the cortical organization of mental functions. Using "living brain imaging" it was found that certain fields of the cortex are responsible for individual cognitive, mental operations . However higher mental functionsarise as a result of the combination of specialized fields due to cortical connections .

In the study of connections - the central problem of brain integration - the idea put forward by the Russian neurophysiological school turned out to be particularly fruitful: a nerve connection is formedbased on coordinating the rhythms of work of neural ensembles located in different parts of the cortex, whichresembles the phenomenon of resonance . At the same time nerve impulses from one group of neurons constantly approach anotherin the increased phase of its excitability , that is, a phenomenon occurs that is to a certain extent similar to the “green wave” when traffic moves. Research by M.N. Livanov and V.S. Rusinov found that the indicator of connection is synchronization of EEG rhythms , including individual components of its spectrum.

In our work on the study of thinking using a new method of mapping cortical connections, we were the first to describe the pattern of connections typical for different types of thinking. The subject was offered tasks on figurative, spatial and abstract-verbal thinking on the monitor screen, and he reported the finished answer verbally or by moving the joystick. In this case, multichannel EEG recording was carried out during the period between the formulation of the problem and its solution.
As a result of the research, it was found that the pattern of connections, symmetrical in the resting state, changes when solving the problem: the connections begin to converge to certain fields of the cortex, which were designated as interaction focuses . At the same time, their topography varies depending on the type of mental activity . Yes, when imaginative thinking(let's say we need to determine what emotions the faces in the photographs express) the foci were localized in the parietotemporal cortex.
At abstract-verbal thinking(solving anagrams or categorizing words) they are located in the frontal cortex.
At spatial thinking, including elements of both figurative and abstract thinking, connections converged to the parietal and frontal cortex.
It was also found that information comes to focusfrom various parts of the cortexhaving their own specialization, communications,which are supported at different frequencies . A certain role is played in the synthesis. motivational component I, just like when sensations arise.

In the focus, the neural groups of which are connected by rigid connections, the synthesis of incoming information occurs, as a result of which, probably, a decision is made. In these works, the idea of ​​information synthesis was extended to thinking, since it turned out that the principle of organization of nervous processes during sensation and thinking is to a certain extent similar . The difference is that
in the first case, two streams of information are compared, and
in the second - several.
Besides, synthesis centers when thinking, they are not in the projection cortex, as when sensations arise, but in the associative cortex. I wonder what when solving any problems, not even requiring a verbal response, at the last stage of the thought process, foci arise in the left temporal region, where the center of speech perception is located (the so-called Wernicke's area), which suggests that verbalization - an important component of human thinking . So, mental perception arises on the basis of a certain organization of nervous processes during which return of excitation to the places of initial projections . With more complex functions, parts of the frontal cortex are involved in this process.

This conclusion was confirmed in our studies of the cortical mechanism of verbal associations, conducted jointly with the laboratory of M. Posner in the USA. The subject had to choose a verb associated with the proposed noun (for example, hammer - hit). Since such a search took less than one second, we developed a method whose time resolution was 100 ms, i.e. was close to duration of individual mental operations . When searching for associations, first a diffuse system of connections arose, which covered fairly large areas of the cortex, then more specialized connections were formed between the left and right frontal cortex . Then powerful connections arose between the frontal and left temporo-parietal cortex. Temporal cortex , thus activated twice : in the first 100-150 ms after the presentation of the word and then in the interval 185-460 ms. Semantics, that is, the meaning of a word, is determined mainly in the frontal, rather than in the temporal cortex. At the same time, to determine the meaning of a sentence - the elementary unit of verbal thinking - it is necessary to interact with the frontal cortex with a zone located in Wernicke's left temporal cortex, the defeat of which leads to impaired understanding of speech.

Remembering the sequence of events. Declarative memory and the hippocampus. Selective attention

An important property of consciousness is the ability to retain in the head the sequence of events that have taken place and to arbitrarily retrieve them from the depths of memory. The French philosopher Henri Bergson (1859-1944) called this property " memory of the soul", as opposed to " body memory", responsible for motor and other skills. Modern terminology calls them declarative and procedural memory, respectively.

Recent decades have seen breakthroughs in the study of their brain mechanisms. Long-term memory is thought to be associated with the association cortex. In addressing memory traces to certain areas of the cortex, an important role is played by the medial parts of the temporal region of the hemispheres, including the entorhinal cortex and the hippocampus (it is a curved strip of neurons, reminiscent of a seahorse in shape, hence the name /see first figure/). The above-mentioned formations have extensive connections both among themselves and with the projection (those where signals from the sensory organs arrive) and associative sections of the cortex. When memorizing, they send a signal to the associative cortex for long-term retention in memory, and if it is necessary to remember, they indicate the address where information related to the received signal is stored. Let's give a simple example. Long-term memory corresponds to a book depository in a library, and the hippocampal complex can be compared to a catalog that shows where the desired book is kept. The difference between the two structures of the hippocampal complex is that the entorhinal cortex is involved in storing information outside of its context (procedural and, for more complex signals, semantic memory), while the hippocampus is important for declarative memory.

To explain the differences between types of memory, we can give the following example. Suppose you meet a person whose face is familiar to you, but you cannot figure out who he is - this recognition, or semantic memory . If you remember who this person is and under what circumstances you met, we are talking about remembering , O declarative memory . Both types of memory have a certain electrophysiological expression in the EP pattern in the form of a positive shift of its late “cognitive” waves with a latency of about 400 ms for semantic and 500-700 ms for declarative memory, which was proven, in particular, using direct assignment of EPs from the hippocampal structures through implanted electrodes. Damage to the hippocampus leads to declarative memory impairment. Such patients can assimilate new information quite well, including language, acquire complex motor skills, study successfully at school and have a high intellectual quotient. At the same time, they are helpless in everyday life, since they do not remember the sequence of events, do not orient themselves in time, and cannot make a plan for the future. English-speaking authors talk about the violation of two properties: belongings (belonging) and appointments (event timing). It is interesting that this disease manifests itself only from the age of 5-6, that is, from the moment when a healthy person begins to remember himself.

Along with the hippocampus, the frontal cortex plays an important role in storing a sequence of events in memory. It is possible to highlight three groups of neurons: alone react to an active signal, others save its trace until the moment when it is necessary to give a behavioral response, and, finally, third include response. Neurons fire sequentially and, as it were, pass the baton from one group to another. We can conclude that the “memory of the soul,” the same one that the writer D. Granin compared to a read book, which you can leaf through, stopping at the desired page, is ensured by the interaction of the frontal cortex and the hippocampus.

Consciousness is closely related to attention : Only what is paid attention to is realized. Our research has shown that memory plays an important role in the mechanisms of selective perception of verbal signals, when a person must react only to certain words, distinguishing them from the mass of others. This situation occurs, for example, when a person is reading a book with the radio on. The difficulty lies in the fact that a word always has a certain significance and carries a semantic load. In our work, we used recordings of brain EPs to words that simultaneously appeared on the monitor screen and were heard through computer speakers. The subject's task was to remember as much as possible more words, coming through one of the channels, ignoring the others. In the next series of experiments, it was necessary to determine whether the word meant an abstract or concrete concept. As already mentioned, memorization and retrieval of verbal information from memory has a certain electrophysiological expression in the “cognitive” components of EP with a latency from 400 to 700 ms. It was found that the EP to a significant stimulus was characterized by a positive shift, while in response to an ignored signal there was a negative shift in potential, that is, a shift opposite in polarity to that which occurs during memorization, which indicates active inhibition of memorization processes (see . rice.). Apparently, selectivity of attention is ensured due to the fact that although unnecessary information is perceived (since the components of the EP responsible for this process are preserved; a person can also recognize this word if he is shown a list of words that he should have ignored), but then the transmission of information to the hippocampal structures is blocked. The advantages of such an organization of verbal attention are that a person can respond to an unexpected signal if a changed situation requires it (in our example, an important message on the radio). Under normal conditions, unnecessary information is simply not stored in the mind.

Thus, the idea of ​​the important role of memory in the emergence of subjective experience receives additional confirmation in attention studies. The results obtained provide grounds for approaching from a new perspective the understanding of the nature of some childhood and senile diseases. The first includes motor hyperactivity and attention deficit syndrome in school-age children, the second includes memory impairment in Alzheimer's disease and cerebral atherosclerosis. It can be assumed that in the latter case, especially in the early stages of the disease, not only memory is weakened, but also the ability to focus attention on necessary information(such attention disorders are known to clinicians). In this case, a new class of drugs may be recommended to combat the disease. The fact is that the parts of the brain that regulate attention and the structures responsible for memory use different mediators. In the first case it is dopamine, in the second it is acetylcholine and glutamate. Available clinical observations indicate the promise of this approach.

Let us summarize the ideas about the most probable mechanisms of consciousness. The fundamental principle is the return of excitation to the sites of original projections, which ensures information synthesis ; the frontal cortex plays an important role in the formation of abstract ideas and speech; The medio-basal regions of the temporal region of the hemispheres are important for maintaining declarative memory and ensuring the processes of selective attention. The comparison of newly received information with past experiences determines the content of consciousness as a constant adjustment of personal experience and what can be called the sense of the inner “I”. At the heart of consciousness is the idea of ​​renewal, which gives life its highest meaning and determines a person’s constant desire for novelty.

Consciousness and artificial intelligence

In conclusion, a few words about another problem that has recently attracted more and more attention - comparisons of the living brain with artificial intelligence. Let us dwell on that aspect of the problem that is most related to consciousness. According to the famous English mathematician and physicist R. Penrose, consciousness cannot be reduced to calculations, since a living brain differs from a computer in that it has the ability to understand. To the question of what understanding is and what its brain mechanisms are, the answer must be given by a physiologist. It appears that understanding arises as a result that, as already mentioned, again the information received is constantly compared in the brain with accumulated experience, with what is stored in memory as a result of learning. It is important that the role of the motivational component in information synthesis is very significant. Thanks to this, the external stimulus is correlated with the past actions of the subject and the satisfaction of a certain need. Understanding, therefore, has a deep vital, adaptive meaning. It is characteristic not only of humans, but also of animals. The animal learns to perform certain actions in order to satisfy a particular need, that is, it begins to understand the connection between external events, its behavior and the achievement of the desired result. Training is also based on this: in order to teach the dog to carry out, that is, understand, certain commands, the trainer uses reinforcement in the form of food or punishment. Essentially, all this initially applies to a person, starting from early childhood. Thus, gaining life experience, the child begins to understand “what is good and what is bad.” A good student receives high grades, a good worker has a higher salary, and a careless worker is fined, a hero receives a reward, and a criminal is sent to prison so that he understands that he cannot break the law. Almost all behavior is based on the same principles.

To substantiate his views, R. Penrose uses Gödel's theorem that it is impossible to prove by calculation the correctness of the basic operations of arithmetic, for example, that 1+1=2. But a living being is convinced of this when it receives two bananas, two enemies or two wives, adding a second (or second) to the first object (or subject) as a result of certain actions. At the same time understanding the essence of doubling(or addition in general) arises in evolution earlier than the ability to count. For example, a case is described when a native inhabitant of the north did not know how many deer he had, but could easily list each one according to their characteristics. The child can also sort out in his memory all the people around him or his toys, although he does not yet know the count. This may seem paradoxical, but understanding both in evolution and in the process of individual developmentprecedes calculation . The point is that calculation is based on abstraction, and this is a function of a more advanced brain. The adaptive effect is achieved when these complex functions, such as the ability to abstract, are combined with simpler ones.

Human consciousness is the result of a long evolution. As the higher functions of the brain improved, the understanding based on the fundamental principles of its operation became more complete.

The above is, of course, far from complete. There is still much we do not know about how the brain works, and especially about what underlies its higher functions and human consciousness. However, progress in this area in recent years is quite obvious, and brain science is gradually moving closer to revealing this secret of nature.

The work was carried out with the support of the Russian Humanitarian Science Foundation, the Russian Foundation for Basic Research, the program of the Presidium of the Russian Academy of Sciences "Basic Sciences for Medicine" and the program of the Russian Academy of Sciences "Integrative Mechanisms of Regulation of Functions and Organisms".

See further
article by academician P.V. Simonova" About two varieties of the unconscious: Sub- and Superconscious "
article "Mechanisms of memory and oblivion "
collections of short news articles" How memory is stored in the brain..."

Literature:
Ivanitsky A.M., Strelets V.B., Korsakov I.A. Information processes of the brain and mental activity. M.: Nauka, 1984. 200 p.
Ivanitsky A.M. The main mystery of nature: how subjective experiences arise based on brain processes// Psychological journal. 1999. T. 20. V. 3. P. 93-104.
Livanov M.N. Spatial organization of brain processes. M.: Nauka, 1972. 181 p.
Penrose R. Shadows of the Mind. In search of a science of consciousness. Part 1. Understanding the mind and new physics. M., Izhevsk: Institute of Computer Technologies, 2003. 368 p.
Simonov P.V. Lectures on the functioning of the brain. Need-information theory of higher nervous activity. M.: Nauka, 2001. 96 p.
Edelman G.M., Tononi G. Consciousness. How matter becomes imagination. London. Pinguin Books. 2000. 274 p.
Ivanitsky A.M., Nikolaev A.R., Ivanitsky G.A. Cortical connectivity during word association search//Int. J. Psychophysiol. 2001. Vol. 42. No. 1. P. 35-53.
Mishkin M., Suzuki W., Gadian D.G., Varha-Khadem F. Hierarchical organization of cognitive memory// Phi. Trans. R. Soc. Lond. B. 1997. V. 352. P. 1461-1467.
Posner M.I., Raichle M.E., 1997. Images of Mind. New York: Scientific American Library. 1997. 255 p.

Consciousness and brain

A person’s consciousness is his life, consisting of an endless change of impressions, thoughts and memories.

The emergence of consciousness is one of the greatest mysteries of nature, the solution of which physicists and writers, philosophers and clergy, doctors and psychologists have been struggling for thousands of years. In recent years, knowledge about how the brain works has accumulated very quickly. Therefore, science has come close to solving the riddle of consciousness. What is the modern view of the relationship between consciousness and processes occurring in the brain? Corresponding Member of the Russian Academy of Sciences, Doctor of Medical Sciences, Head of the Laboratory of Human Higher Nervous Activity at the Institute of Higher Nervous Activity and Neurophysiology of the Russian Academy of Sciences, Alexey Mikhailovich Ivanitsky, tried to answer this not only natural-scientific, but also philosophical question in the program “Obvious-Incredible.”

A person’s consciousness is, in essence, his life, consisting of an endless change of impressions, thoughts and memories. The mystery of our brain is multifaceted and affects the interests of many sciences that study the mysteries of existence. One of the main questions is how consciousness is connected to the brain. This problem is at the intersection of natural science and humanities, since consciousness arises on the basis of processes occurring in the brain, but its content is largely determined by social experience. The solution to this puzzle could build a bridge between the two main types of scientific knowledge and contribute to the creation of a unified picture of the universe that organically includes man and his spiritual world. This is probably the highest goal of science, the achievement of which is necessary to satisfy the inherent human desire for comprehensive knowledge. But the practical significance of this problem for medicine, education, organization of work and leisure is also great.

Interest in the relationship between consciousness and the brain arose a long time ago. For Russian physiology, starting from the time of I.M. Sechenov and I.P. Pavlova, he is to a certain extent traditional. However, for a long time the solution to such a complex problem was considered a matter of the distant future. The understanding that the study of the problem of consciousness is an urgent task of today came to physiologists relatively recently: the rapid progress of brain science brought this topic to the front pages of neuroscience journals. There even arose, in the figurative expression of the English scientist John Taylor, a “race for consciousness.” The breakthrough in this field was largely due to the advent of “living brain imaging” techniques such as positron emission tomography, functional magnetic resonance, and multichannel recording of the brain’s electric and magnetic fields. The latest devices have made it possible to see on the display screen which zones are activated when performing various tasks that require mental effort, as well as to accurately determine the location of lesions in diseases of the nervous system. Scientists have gained the ability to obtain corresponding images in the form of colorful maps of the brain.

From a philosophical point of view, one may wonder how legitimate it is at all to try to explain by the movement of nerve impulses what we perceive as color or sound. Sensation is a purely personal feeling, the “inner theater” of each of us, and the task of brain science is to understand what neural processes lead to the emergence of a subjective image. At the same time, the mystery of the human psyche is not unique in its methodological complexity and stands among other mysteries of nature. Essentially, the emergence of a new quality occurs at each stage of fundamental complication of natural processes. American scientists F. Crick and K. Koch consider the origin of life as a result of the action of DNA chains and enzyme proteins to be an example of a qualitative transition comparable in complexity to the emergence of consciousness. The properties inherent in living objects do not follow directly from the physicochemical properties of each of these molecules. This example seems especially convincing in the mouth of F. Crick, one of the discoverers of the genetic code.

The experience of scientific knowledge shows that a complex phenomenon, as a rule, does not arise out of nothing, but develops in the process of evolution from simpler forms. The same fully applies to subjective experiences. They move from elementary manifestations, such as sensations and emotions, to higher-order consciousness associated with abstract thinking and speech. Based on these considerations, there are several approaches to the study of consciousness, which, however, do not exclude, but complement each other, explaining phenomena of varying degrees of complexity. At the same time, some basic principles of the organization of nervous processes, discovered in the early stages of the evolution of the psyche, gradually acquire more complex forms to ensure their highest manifestations.

Return of excitation and mechanism of sensations

The first approach to understanding the principles of the nature of the psyche is based on the idea that subjective experience arises as a result of a certain organization of processes occurring in the brain and the comparison of new information in the cortex with that extracted from memory. Information about external events is, as it were, projected onto the individual experience of the subject. This occurs as a result of the circular movement of excitation, which, after additional processing in other brain structures, returns to the places of initial projections. We first put forward such a hypothesis in the 1970s. as a result of research into the brain mechanisms of sensation. Currently, it is shared by many specialists.

As already mentioned, this hypothesis was based on our studies of the mechanism of sensations. We studied evoked potentials (EPs) of the brain, that is, its electrical response to a newly received signal. The EP is a complex oscillation consisting of a number of sequential components, and it was necessary to understand what information processes of the brain they reflect. Analysis of the data led to the conclusion that early EP waves are associated with the arrival of impulses into the cortex along sensory pathways from the sense organs. They reflect the physical parameters of the stimulus. Late waves caused by the transfer of excitation from motivational centers characterize the significance of the signal. Next, the question arose of how these information processes relate to subjective experience. I turned to the director of the Institute of Psychology of the Russian Academy of Sciences - in those years this post was held by Corresponding Member of the USSR Academy of Sciences B.F. Lomov. His answer was unexpected and interesting. He said that in psychology there is a theory that is close in its provisions to our views. The discussion was about the theory of signal detection, which considers perception as the result of the interaction of sensory and motivational factors, which are called, respectively, an indicator of sensory sensitivity and a decision criterion. It is interesting that this approach was borrowed by psychology from technology, in particular, from the principle of radar design, consisting of a sensitive receiver and a signal identification system.

The synthesis of information about the physical and signal properties of the stimulus on the neuron of the visual cortex leads to the emergence of a sensation, which is then recognized and categorized with the participation of the frontal cortex. Sensations arise as a result of the cyclic movement of nerve impulses and the synthesis in the projection cortex of sensory information with information extracted from memory.
The numbers in the boxes are milliseconds after stimulus presentation.

In the course of further research, it was necessary to compare two concepts in one experiment: physiological and psychological. The difficulty was that the detection theory works in the region of weak signals close to the threshold, since the calculation of the corresponding perceptual indices is based on the ratio of correct and erroneous reactions. At the same time, recording EP with its early waves requires fairly intense stimuli. It was decided to use a differential threshold rather than an absolute one. The participant in the experiment had to distinguish the intensity of two stimuli of similar strength (visual in one series, cutaneous in the other), while brain EPs to the presented stimuli were recorded. To obtain quantitative parameters of sensations, methods of signal detection theory were used with the calculation of the two mentioned indicators. Then a correlation was obtained between physiological and psychological indicators, and the results, in principle, turned out to be similar for vision and skin sense. As expected, the early waves of EPs were found to correspond with the sensory factor of psychophysics, and the later ones - with the decision criterion. Somewhat unexpected and therefore most interesting was the relationship between intermediate waves of EP of the projection cortex (where impulses from the sensory organs arrive) with both indices of perception, that is, with both the indicator of sensory sensitivity and the decision criterion. This double correlation reflects the synthesis of information about the physical and signal properties of the stimulus on the neurons of the projection cortex. These waves appeared in the EP 150-180 ms after the stimulus.

It is fundamentally important that this time coincided quite accurately with the rate of occurrence of sensations obtained earlier during psychophysical experiments. Back in the 20-30s. last century, it was found that sensations appear only 100-150 ms after the presentation of the stimulus. In this case, methods were used mainly based on the phenomenon of “reverse masking”. Its essence is this: if after one weak stimulus a second, stronger one follows after a short interval, the first is not perceived. By gradually increasing the time interval between both signals, it is possible to calculate the moment when the masking effect disappears, since the sensation of the first stimulus has time to form. It was found that the sensation appears approximately 150 ms after the stimulus. The most reliable data, however, were obtained when direct stimulation of the cortex with a short magnetic pulse, which was applied to the scalp directly above the corresponding area of ​​the cerebral cortex, was used as a masking signal - the results obtained practically coincided with those given above. It is important that the magnetic pulse caused a masking effect only if it affected the occipital cortex, which projects for visual stimuli, that is, only where the above-described double correlation of EP waves with perceptual indices was observed. The 150 ms interval is called the “psychological refractory period,” and the mental experience cannot be shorter than it. It is interesting to compare the given indicators with physiological data on the duration of information processing for a single stimulus in the visual cortex, which is about 200 ms (I.A. Sheelev).

Src="mind/ochevidnoe2.jpg" width="470">
On brain maps, cortical areas are color coded, depending on the normalized number of connections that connect to them. With figurative thinking, the foci are located in the parietotemporal cortex, and with verbal thinking, in the frontal cortex. The speech perception center in the left temporal cortex (Wernicke's area) is involved in both cases.

Based on data on the physiological mechanism of evoked potential waves and their connection with parts of the brain, we described the process that ensures the synthesis of information (see inset). It involves the circular movement of excitation across parts of the brain. From the projection cortex, which receives signals from the sensory organs, excitation enters the associative cortex (inferotemporal for visual stimuli), where information is compared with a standard and recognized. Then the excitation moves to the entorhinal cortex, located on the inner surface of the temporal lobe of the hemispheres and related to memory. There the significance of the signal is determined, its relationship to a particular need of the body. Then the excitation impulses move to the motivational centers of the diencephalon, from where they return again through a system of diffuse projections to the cortex, including the primary projection zones. After 100 ms, connections also arise between the projection and frontal cortex. This cycle, which lasts about 150 ms, is called the “circle of sensations.” Its essence is that it provides a comparison of the sensory signal with information extracted from memory, including data on the significance of the information received, which presumably underlies the transition of the physiological process to the level of mental, subjective experience. As a result, the resulting sensation not only accurately conveys the physical characteristics of the stimulus, but is also emotionally charged. The above concept is called the information synthesis hypothesis.

In subsequent years, it was confirmed by the results of many studies, including data on the topography of the brain regions included in the “circle of sensations”, and the use of the very idea of ​​\u200b\u200breturn of excitation to explain the mechanisms of consciousness. Among the most significant are the works of Nobel laureate J. Edelman, who used the term “re-entry,” which denotes not feedback, which is usually understood as a correction signal, but input additional information, obtained from a survey of brain structures associated with memory function and motivation.

In addition to information synthesis, the return of excitation along diffuse projections also ensures the integration of individual stimulus features into a single image. Research in recent years has shown that the rhythm of the electroencephalogram (EEG) with a frequency of about 40 Hz plays an important role. It is the synchronization of the biopotential of the brain at a certain rhythm that creates the conditions for combining neural networks into a single system, which is necessary to maintain consciousness.

Sensation refers to fairly simple mental phenomena, which some scientists attribute to the so-called primary consciousness, which also includes emotions, to the study of which P.V. made an outstanding contribution. Simonov. He was the first to propose a formula according to which the strength of emotion E is proportional to the need P, multiplied by the difference between the information available to the individual and what he needs to satisfy this need:

E = P (Inf. available - Inf. required)

From this formula it follows that emotions, as well as sensations, arise as a result of comparing two information flows. Thus, there is a certain universal pattern at work here.

Of interest is the question of how, in the course of evolution, a system for returning excitation and comparing two information flows could arise. In accordance with the concept of N. Humphrey, the mental appeared as a result of the action of branches of motor fibers extending from the cortex to sensory pathways heading to the cortex, which made possible the directed regulation of information arriving to the cortex. In simpler systems, such a process could occur in the periphery, but intracortical methods gradually developed for executive centers to filter the most significant information for determining behavior, which could act in the absence of motor commands. N. Humphrey called such a mechanism a “sentient loop”, which is even terminologically close to our “circle of sensations”.

Speaking about the mechanisms of sensations, it is appropriate to recall the words once spoken by I. Goethe: “If I did not carry the whole world within me, I would be blind with healthy eyes.”

Consciousness and speech. Thinking e. Frontal cortex

More complex mental phenomena, primarily associated with the appearance of speech, are classified as consciousness of a higher order. According to P.V. Simonov, it arose as a result of communication between people. This process is also associated with the specialization of the hemispheres. An interesting opinion was expressed by M. Corballis: he believes that speech developed from the need to convey rather complex information, first at the level of exchange of gestures. Only later, when the forelimbs were occupied with tools, hand movements began to be combined with vocal signals, which gradually turned into the main means of communication. Since the vocal centers in many animals are located on the left, cortical speech centers also arose in the left hemisphere. At the same time, the functions of Broca's area - the motor center of speech, located in a person's left frontal region - also changed. Monkeys have similar cortical zones in both hemispheres, but their function is somewhat different: there are “mirror neurons” that control actions that repeat the movements of another individual (“monkeying”). It is curious that in young children the speech motor centers are also bilateral, and damage to one of them does not lead to loss of speech, as happens in adults. Speaking about the mechanisms of higher mental functions, especially thinking, it is necessary to say about the works of N.P. Bekhtereva and her school.

The last years of the last century, declared the “decade of the brain,” were marked by the rapid accumulation of knowledge about the principles of cortical organization of mental functions. Using “images of the living brain,” it was established that certain fields of the cortex are responsible for individual cognitive and mental operations. However, higher mental functions arise as a result of the unification of specialized fields due to cortical connections.

In the study of connections - the central problem of brain integration - the idea put forward by the Russian neurophysiological school that a nervous connection is formed on the basis of coordinating the rhythms of the work of neural ensembles located in different parts of the cortex, which resembles the phenomenon of resonance, turned out to be especially fruitful. In this case, nerve impulses from one group of neurons constantly approach another in an increased phase of its excitability, that is, a phenomenon occurs that is to a certain extent similar to the “green wave” during traffic movement. Research by M.N. Livanov and V.S. Rusinov established that an indicator of communication is the synchronization of EEG rhythms, including individual components of its spectrum.

Cortical connections in two subranges of beta rhythm frequencies when solving a spatial (left) and verbal (right) task. In the first case, the subject had to determine whether the two figures shown to him were identical or mirror symmetrical; in the second, he had to find a word that belonged to a different category than the other three. Connections are shown as they appear in the process of solving the problem, in accordance with the given time scale.

In our work on the study of thinking using a new method of mapping cortical connections, we were the first to describe the pattern of connections typical for different types of thinking. On the monitor screen, the subject was offered tasks for figurative, spatial and abstract-verbal thinking, and he reported the finished answer verbally or by moving the joystick. In this case, multichannel EEG recording was carried out during the period between the formulation of the problem and its solution.

As a result of the research, it was found that the pattern of connections, symmetrical in the resting state, changes when solving a problem: connections begin to converge to certain fields of the cortex, which were designated as foci of interaction. Moreover, their topography differs depending on the type of mental activity. Thus, during figurative thinking (for example, it is necessary to determine what emotions the faces in photographs express) the foci were localized in the parietotemporal cortex. During abstract-verbal thinking (solving anagrams or categorizing words), they are located in the frontal cortex (see figure). With spatial thinking, which included elements of both figurative and abstract thinking, connections converged to the parietal and frontal cortex (see figure below). It was also found that information comes to the foci from various parts of the cortex, which have their own specialization, through connections that are maintained at different frequencies. A certain motivational component plays an important role in synthesis, just as when sensations arise.

In the focus, the neural groups of which are connected by rigid connections, the synthesis of incoming information occurs, as a result of which, probably, a decision is made. In these works, the idea of ​​information synthesis was extended to thinking, since it turned out that the principle of organization of nervous processes in sensation and thinking is to a certain extent similar. The difference is that in the first case there is a comparison of two streams of information, and in the second - several. In addition, the centers of synthesis during thinking are not located in the projection cortex, as when sensations arise, but in the associative cortex. It is interesting that when solving any problems, even those that do not require a verbal response, at the last stage of the thought process, focuses appear in the left temporal region, where the center of speech perception is located (the so-called Wernicke's area), which suggests that verbalization is an important component of human thinking I. So, mental perception arises on the basis of a certain organization of nervous processes, during which the return of excitation to the places of initial projections occurs. With more complex functions, parts of the frontal cortex are involved in this process.

This conclusion was confirmed in our studies of the cortical mechanism of verbal associations, conducted jointly with the laboratory of M. Posner in the USA. The subject had to choose a verb associated with the proposed noun (for example, hammer - hit). Since such a search took less than one second, we developed a method whose temporal resolution was 100 ms, i.e., was close to the duration of individual mental operations. When searching for associations, a diffuse system of connections first emerged, which covered fairly large areas of the cortex, then more specialized connections were formed between the left and right frontal cortex. Then powerful connections arose between the frontal and left temporo-parietal cortex, thus being activated twice: in the first 100-150 ms after the presentation of the word and then in the interval 185-460. ms. Semantics, that is, the meaning of a word, is determined mainly in the frontal, and not in the temporal cortex. At the same time, to determine the meaning of a sentence - the elementary unit of verbal thinking - interaction of the frontal cortex with the area located in the left temporal cortex of Wernicke is necessary. , the defeat of which leads to impaired speech understanding.

BRAIN STRUCTURES ASSOCIATED WITH MEMORY FUNCTION

Remembering the sequence of events. Declarative memory and the hippocampus. Selective attention

An important property of consciousness is the ability to retain in the head the sequence of events that have occurred and to voluntarily retrieve them from the depths of memory. The French philosopher Henri Bergson (1859-1944) called this property “memory of the soul,” in contrast to “memory of the body,” responsible for motor and other skills. Modern terminology refers to them as declarative and procedural memory, respectively.

Recent decades have seen breakthroughs in the study of their brain mechanisms (see figure below). Long-term memory is thought to be associated with the association cortex. In addressing memory traces to certain areas of the cortex, the medial parts of the temporal region of the hemispheres, including the entorhinal cortex and the hippocampus (it is a curved strip of neurons, reminiscent of a seahorse in shape, hence the name), play an important role. The above-mentioned formations have extensive connections both among themselves and with the projection (those where signals from the sensory organs arrive) and associative sections of the cortex. When memorizing, they send a signal to the associative cortex for long-term retention in memory, and if it is necessary to remember, they indicate the address where information related to the received signal is stored. Let's give a simple example. Long-term memory corresponds to a book depository in a library, and the hippocampal complex can be compared to a catalog that shows where the desired book is kept. The difference between the two structures of the hippocampal complex is that the entorhinal cortex is involved in storing information outside of its connection with the context (procedural, and for more complex signals - semantic memory), and the hippocampus is important for declarative memory. To explain the differences between types of memory, we can give the following example. Suppose you meet a person whose face is familiar to you, but you cannot understand who he is - this is recognition, or semantic memory. If you remember who this person is and under what circumstances you met, we are talking about remembering, about declarative memory. Both types of memory have a certain electrophysiological expression in the EP pattern in the form of a positive shift of its late “cognitive” waves with a latency of about 400 ms for semantic and 500-700 ms for declarative memory, which was proven, in particular, using direct assignment of EPs from the hippocampal structures through implanted electrodes. Damage to the hippocampus leads to declarative memory impairment. Such patients can assimilate new information quite well, including language, acquire complex motor skills, study successfully at school and have a high intellectual quotient. At the same time, they are helpless in everyday life, since they do not remember the sequence of events, do not orient themselves in time, and cannot make a plan for the future. English-speaking authors talk about the violation of two properties: belongings (belonging) and appointments (event timing). It is interesting that this disease manifests itself only from the age of 5-6, that is, from the moment when a healthy person begins to remember himself.

Along with the hippocampus, the frontal cortex plays an important role in storing a sequence of events in memory. In it, three groups of neurons can be distinguished: some react to the current signal, others retain its trace until the moment when it is necessary to give a behavioral response, and, finally, others turn on the response. Neurons discharge sequentially and, as it were, pass the baton from one group to another. We can conclude that the “memory of the soul,” the same one that the writer D. Granin compared to a read book, which you can leaf through, stopping at the right page, is ensured by the interaction of the frontal cortex and the hippocampus.

Consciousness is closely related to attention: only what is paid attention to is realized. Our research has shown that memory plays an important role in the mechanisms of selective perception of verbal signals, when a person must react only to certain words, distinguishing them from the mass of others. This situation occurs, for example, when a person is reading a book with the radio on. The difficulty lies in the fact that a word always has a certain significance and carries a semantic load. Our work used recordings of brain EPs to words that simultaneously appeared on a monitor screen and were heard through computer speakers. The subject's task was to remember as many words as possible that came through one of the channels, ignoring the others. In the next series of experiments it was necessary to determine whether the word meant an abstract or concrete concept. As already mentioned, memorizing and retrieving verbal information from memory has a certain electrophysiological expression in the “cognitive” components of EP with a latency from 400 to 700 ms. It was found that the EP to a significant stimulus was characterized by a positive shift, while in response to an ignored signal there was a negative shift in the potential a, that is, a shift opposite in polarity to that which occurs during memorization, which indicates active inhibition of memorization processes (see inset above). Apparently, selectivity of attention is ensured due to the fact that although unnecessary information is perceived (since the EP components responsible for this process are preserved; a person can also recognize this word if he is shown a list of words that he should have ignored), but then the transmission of information to the hippocampal structures is blocked. The advantages of such an organization of verbal attention are that a person can respond to an unexpected signal if a changed situation requires it (in our example, an important message on the radio). Under normal conditions, unnecessary information is simply not stored in the mind.

Thus, the idea of ​​the important role of memory in the emergence of subjective experience receives additional confirmation in attention studies. The results obtained provide a basis for approaching the understanding of the nature of some childhood and senile diseases from a new perspective. The first includes motor hyperactivity and attention deficit syndrome in school-age children, the second includes memory impairment in Alzheimer's disease and cerebral atherosclerosis. It can be assumed that in the latter case, especially in the early stages of the disease, not only memory is weakened, but also the ability to focus attention on the necessary information (such attention disorders are known to clinicians). In this case, a new class of drugs may be recommended to combat the disease. The fact is that the parts of the brain that regulate attention and the structures responsible for memory use different mediators. In the first case it is dopamine, in the second it is acetylcholine and glutamate. Available clinical observations indicate the promise of this approach.

Let us summarize the ideas about the most probable mechanisms of consciousness. The fundamental principle is the return of excitation to the places of initial projections, which ensures information synthesis; the frontal cortex plays an important role in the formation of abstract ideas and speech; The medio-basal regions of the temporal region of the hemispheres are important for maintaining declarative memory and ensuring the processes of selective attention. The comparison of newly received information with past experiences determines the content of consciousness as a constant adjustment of personal experience and what can be called the sense of the inner “I”. At the heart of consciousness is the idea of ​​renewal, which gives life its highest meaning and determines a person’s constant desire for novelty.

Consciousness and artificial intelligence

In conclusion, a few words about another problem that has recently attracted more and more attention - comparisons of the living brain with artificial intelligence. Let us dwell on that aspect of the problem that is most related to consciousness. According to the famous English mathematician and physicist R. Penrose, consciousness cannot be reduced to calculations, since a living brain differs from a computer in that it has the ability to understand. To the question of what understanding is and what its brain mechanisms are, the answer must be given by a physiologist. It seems that understanding arises as a result of the fact that, as already mentioned, newly received information is constantly compared in the brain with accumulated experience, with what is stored in memory as a result of learning. It is important that the role of the motivational component in information synthesis is very significant. Thanks to this, the external stimulus is correlated with the past actions of the subject and the satisfaction of a certain need. Understanding, therefore, has a deep vital, adaptive meaning. It is characteristic not only of humans, but also of animals. The animal learns to perform certain actions in order to satisfy a particular need, that is, it begins to understand the connection between external events, its behavior and the achievement of the desired result. Training is also based on this: in order to teach the dog to carry out, that is, understand, certain commands, the trainer uses reinforcement in the form of food or punishment. Essentially, all this initially applies to a person, starting from early childhood. Thus, gaining life experience, the child begins to understand “what is good and what is bad.” A good student receives high grades, a good worker has a higher salary, and a careless worker is fined, a hero receives a reward, and a criminal is sent to prison so that he understands that he cannot break the law. Almost all behavior is based on the same principles.

To substantiate his views, R. Penrose uses Gödel’s theorem that it is impossible to prove by calculation the correctness of the basic operations of arithmetic, for example, that 1+1=2. But a living being is convinced of this when it receives two bananas, two enemies or two wives, adding a second (or second) to the first object (or subject) as a result of certain actions. Moreover, understanding the essence of doubling (or addition in general) appears in evolution earlier than the ability to count. For example, a case is described when a native inhabitant of the north did not know how many deer he had, but could easily list each one according to their characteristics. The child can also sort out in his memory all the people around him or his toys, although he does not yet know the count. It may seem paradoxical, but understanding, both in evolution and in the process of individual development, precedes calculation. The point is that calculation is based on abstraction, and this is a function of a more advanced brain. The adaptive effect is achieved when these complex functions, such as the ability to abstract, are combined with simpler ones.

Human consciousness is the result of a long evolution. As the higher functions of the brain improved, the understanding based on the fundamental principles of its operation became more complete.

The above is, of course, far from complete. There is still much we do not know about how the brain works, and especially about what underlies its higher functions and human consciousness. However, progress in this area in recent years is quite obvious, and brain science is gradually moving closer to revealing this secret of nature.

The work was carried out with the support of the Russian Humanitarian Science Foundation, the Russian Foundation for Basic Research, the program of the Presidium of the Russian Academy of Sciences "Basic Sciences for Medicine" and the program of the Russian Academy of Sciences "Integrative Mechanisms of Regulation of Functions and Organisms".

ABOUT THE AUTHOR:
Ivanitsky Alexey Mikhailovich, Corresponding Member of the Russian Academy of Sciences, Professor, Doctor of Medical Sciences. Head of the Laboratory of Human Higher Nervous Activity, Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences.

LITERATURE:
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Simonov P.V. Lectures on the functioning of the brain. Need-information theory of higher nervous activity. M.: Nauka, 2001. 96 p.
Edelman G.M., Tononi G. Consciousness. How matter becomes imagination. London. Pinguin Books. 2000. 274 p.
Ivanitsky A.M., Nikolaev A.R., Ivanitsky G.A. Cortical connectivity during word association search//Int. J. Psychophysiol. 2001. Vol. 42. No. 1. P. 35-53.
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Modern science proceeds from the idea of ​​the biological unity of animals and humans. And because of this, sometimes conclusions are drawn about the complete analogy of mental processes in humans and animals. But human consciousness arose and developed in close dependence with the emergence and development of the human brain, this is indicated by the fact that the level of reflective ability of consciousness also depends on the level of complexity of the organization of the brain.

The main function of the human brain is the storage and processing of information received by a person in the process of cognitive activity. The human brain is symmetrical (hemispheres), but functionally there is a great difference between the hemispheres.

The left hemisphere is responsible for all types of speech activity (understanding, speaking), ensures the processes of speech and writing, reading, carries out counting operations, and classifies objects into certain classes.

The right hemisphere controls orientation in one’s own body (perception of spatial relationships, correct coordination).

Consciousness not only reflects reality, but also allows us to express certain attitudes towards it. Therefore, the structure of consciousness includes: memory, emotions, feeling, will, motivation.

Spirkin's concept

By consciousness we mean the ability to ideally reflect reality, the transformation of the objective content of an object into the subjective content of a person’s mental life.

Consciousness is not just an image, but a mental (ideal) form of activity that is focused on reflecting and transforming reality.

Consciousness is the highest function of the brain, peculiar only to humans and associated with speech, which consists in a generalized, evaluative and purposeful reflection and transformation of reality, as well as in the preliminary mental construction of actions and the anticipation of their results.

Ivanov's concept (consciousness according to Ivanov)

Ivanov represents the field of consciousness in the form of a circle. Each sector is responsible for a specific function.

First sector: the sphere of bodily-perceptual abilities and knowledge obtained on their basis. These abilities include: sensations, perception, specific ideas, with the help of which a person receives primary information about the external world, about his own body and about its relationships with other bodies. The main goal of this sphere of knowledge is the usefulness and expediency of the behavior of the human body in the natural, social, and natural world around it. human bodies.

Second sector: logical-conceptual components of consciousness. With the help of thinking, a person goes beyond the immediate sensory data into the essential levels of cognizable objects. This area includes: general concepts, analytical-synthetic mental operations, hard logical proofs. The main goal is truth.

Sectors 1 and 2 form the external-cognitive component of consciousness.

Third sector: it is associated with the emotional component of consciousness. She is deprived of direct communication with the outside world. This is the sphere of personal, subjective psychological experiences, memories, premonitions. This area includes:

Instinctive-affective states (premonition, vague experiences, stress, hallucinations)

· Emotions (anger, fear, delight)

Feelings that are more distinct (pleasure, love, sympathy, antipathy)

The main goal of the sphere is the principle of pleasure.

Fourth sector: value-motivational component. It contains the highest motives of activity and spiritual ideals of the individual, as well as the ability to form them and creatively understand them in the form of fantasies and imagination. The main goal of the sector is beauty, truth and justice.

Sectors 3 and 4 form the value-emotional component of consciousness.

The problem of consciousness is related to the question of self-awareness. It is believed that objective consciousness is focused on understanding the world around a person; with self-awareness, the subject makes himself an object. The object of analysis becomes one’s own ideas, thoughts, feelings, experiences, goals, actions, position in the family and team.

Sources of consciousness

1. External subject and spiritual world, natural social and spiritual phenomena that are reflected in consciousness in the form of conceptual images

2. Sociocultural environment, general concepts, ethical and aesthetic attitudes, social ideals, legal norms, knowledge accumulated by society

3. The spiritual appearance of the individual, his own unique experience of life, experiences, i.e. in the absence of direct external influences, a person is able to rethink his past and control his future

4. Brain. The chemical and biological state of the brain is one of the factors influencing the nature of perception of the world.

5. Cosmic information-semantic field (the brain takes information from space)

Unconscious

consciousness brain spiritual human

Along with consciousness, in the human psyche there is a sphere of the unconscious.

The unconscious is a set of mental phenomena and actions that lie outside the sphere human mind, unaccountable and not amenable (in at the moment) control by knowledge. The unconscious includes:

Hypnotic state

State of insanity

Reservations, clerical errors

Everything that is not currently in the focus of the individual’s consciousness, but can be included in consciousness through memory, should not be classified as unconscious.

Instincts can and do generate subconscious desires, emotions, and volitional impulses in a person, but later they can enter the sphere of consciousness, or the other way around can happen. The so-called “Automatisms” and intuition can arise with the help of consciousness, but then move into the sphere of the unconscious.

The unconscious according to Freud.

S. Freud came to the conclusion about the essential, and sometimes even decisive, role of the unconscious. According to Freud, the human psyche has three spheres: “It”, “I”, “super-self”.

“It” is the sphere of the unconscious, in which various biological influences are concentrated: sexual desires, and ideas repressed from consciousness. The principles of pleasure and enjoyment dominate here.

“I” is the sphere of the conscious, a kind of mediator between a person’s unconscious influences and external reality, cat. includes the natural and social environment. The “I” level seeks to replace the principle of pleasure with the principle of reality, although it does not always succeed.

“Super-th” - intrapersonal conscience, attitudes of society, ideals, norms, values, i.e. a kind of moral censorship.

“I” strives to be a mediator between the world and “It” and for the world “It”.

Freud exaggerated the importance of the unconscious. Freud exaggerated the importance of the “id” in relation to the “I” and said that a person is forced to constantly be tormented and torn between biological influences and perceived social norms. According to Freud, the biological unconscious is decisive.

G. Jung identified the so-called “archetypes” in the sphere of the unconscious. If the complexes of experiences repressed from consciousness into the unconscious in Freud are the result of individual life, then Jung’s archetypes are associated with the collective life of people and are fixed in a person’s life, passed on from generation to generation.

The “Shadow” archetype represents the image of the base and antisocial in a person.

The “Persona” archetype is a mask; underneath it lies the “shadow” archetype; a person very often uses it to hide an antisocial essence.

The “Anime” archetype is the feminine principle of a man.

Archetype "Animus" - the masculine principle of a woman

They lead to mutual understanding between men and women, but can lead to mental crises when idealized ideas do not coincide with a real person.

The “Self” archetype predetermines all human life activities aimed at achieving values ​​and unity of its constituent parts.

The unconscious and the conscious are two relatively independent sides of a single psychological reality of a person. Contradictions and conflicts often arise between them, but they are still interconnected, interact with each other and are capable of achieving harmonious unity.

Language and thinking

Language - specific method human - the way of being consciousness. It serves to record, reproduce, transmit and receive thoughts. Although thoughts usually arise before they are expressed in language, it is through language that they gain their clarity. There are 2 language functions:

thinking

Thinking is a complex, multifaceted mental process that has its own structure. From the point of view of the method of its external expression, it has 2 forms:

silent inner speech, wordless thinking, outwardly expressed by silence.

A physically expressed form of thinking, having a verbal or non-verbal form, forms of words, gestures and facial expressions (verbal and non-verbal)

Thinking can also be classified depending on the nature of the objects it reflects:

concrete thinking, which is expressed in terms, words, signs, denoting individual specific things. This type of thinking is associated with material reality.

Abstract thinking, expressed in generalizing, abstract concepts, denoting invisible connections between types, genera, classes of objects and phenomena. He is separated from material reality.

Both abstract and concrete thinking are expressed in signs, symbols, words, in oral and written speech, in language.

Language is a material medium of expression of the ideal spirit, consciousness, thinking.

Types of languages:

speech form - oral and written speech

non-verbal - facial expressions, gestures, body movements.

Special languages ​​- language of sciences (mathematics, chemistry)

Various signaling systems - road signs, marine signals, diagrams.

Language could only arise in society, i.e. it is socially conditioned. Language, as a means of communication, plays an important role in the social and labor activities of people.

The commonality between consciousness and language is that they 1) historically arose simultaneously, i.e. ideas cannot exist separately from language. 2) both thinking and language are the product of a long socio-historical process. Language and thinking are not identical.

a word reflects only the essence of an object, not the entire object, with all its diverse properties. Thought embraces larger number properties of an object.

In the triad, consciousness, word, reality, the word occupies the middle position, connecting consciousness with reality. Thus, the word influences both thinking (explaining it) and reality (transformation).

Thought is fleeting, unstable, mortal. The word is more stable, stable and immortal. The word is a sparrow - if it flies out, you won’t catch it.

website- The role of the brain as a source of consciousness and thinking is questioned by neurophysiologist, academician of the Russian Academy of Sciences Natalya Bekhtereva. In her book “The Magic of the Brain and the Labyrinths of Life” she writes: “Deepening into brain research, including on the basis of fundamentally new technologies that have not yet been created, can answer the question of whether there is a brain code for thinking. If the answer (final!) is negative and what we observe is not the code of thinking itself, then the restructuring of impulse activity, correlated with the areas of the brain activated during mental activity, is a kind of “code for the entry of a link into the system.” If the answer is negative, it will be necessary to reconsider both the most general and most important positions in the problem “Brain and Psyche”. If nothing in the brain is connected specifically to the subtle structure of our thinking, then what is the role of the brain in this process? Is this just the role of “territory” for some other processes that do not obey brain patterns? And what is their connection with the brain, what is their dependence on the brain substrate and its state?

At the same time, it has been scientifically proven that consciousness is always connected with processes occurring in the brain and does not exist apart from them.

The brain is a vital organ. Even its insignificant damage can cause serious harm to a person, causing loss of consciousness, amnesia, and mental disorder. At the same time, medical practice has documented cases of severe brain damage, including congenital defects up to the absence of a brain, in which, however, the person continued to live and function normally.

In medical practice, there are enough cases of people living without a brain, which forced us to reconsider the accepted dogmas in neurophysiology.

Cases from practice

There is evidence from the 16th century of a boy without a brain. The boy died 3 years later after a severe skull injury. During the autopsy, no brain was found.

In the 19th century, Professor Hufland (Germany) described and documented in detail an amazing case. He had the opportunity to perform an autopsy of the skull of a very elderly man who died as a result of paralysis. Until the very last minutes, the patient retained his mental and physical abilities. The result left the professor extremely confused: instead of the brain, there were 28 grams of water in the skull of the deceased.

In 1940, Dr. Augusto Iturricha, in his report at a meeting of the Bolivian Anthropological Society, spoke about a 14-year-old boy who was in his clinic diagnosed with a brain tumor. The patient remained conscious and of sound mind until his death, only complaining of severe headache. During the autopsy, the doctors were extremely amazed. The entire brain mass was separated from the internal cavity of the skull and looked long rotten. Blood had no access to it. In other words, the boy simply did not have a brain. The normal functioning of the boy’s consciousness remained a mystery to doctors.

1980 An article was presented in the American journal Science that described interesting case no less than the previous one, a young student went to the hospital with a slight malaise. The doctor who examined the student drew attention to the head volume exceeding the norm. As a result of the scan, the student, like the clerk, was diagnosed with hydrocephalus, but his level of intelligence was many times higher than the norm.

In 2002, a girl from Holland survived a serious operation. She had the left hemisphere of her brain removed, which is still believed to contain the speech centers. Today, the child amazes doctors by the fact that he has perfectly mastered two languages ​​and is learning a third. Dr. Johannes Borgstein, who is observing the little Dutch girl, says that he has already advised his students to forget all the neurophysiological theories that they are studying and will still study.

In 2007, a British medical journal wrote an article called “The Clerk’s Brain.” It told the absolutely fantastic story of a French clerk who sought medical help. A 44-year-old resident of Marseille had pain in his leg. As a result of long examinations in order to find the cause of the disease, doctors prescribed a tomography (brain scan), as a result of which the doctors discovered that the clerk does not have a brain, instead of brain cells, the main volume in his head is occupied by cerebrospinal fluid. Hydrocephalus or (dropsy of the brain) is a well-known phenomenon in medicine, but the fact that a clerk with such a disease functioned quite normally and his IQ was no different from the IQ normal person, amazed the doctors.

In another case, an American named Carlos Rodriguez lives practically without a brain after an accident. More than 60% of his brain was removed, but this did not affect his memory or cognitive abilities.

The above facts force scientists to admit the fact of the existence of consciousness independent of the brain.

The fact that consciousness exists independently of the brain is confirmed, for example, by studies conducted by Dutch physiologists under the leadership of Pim van Lommel. The results of a large-scale experiment were published in the most authoritative English biological journal, The Lancet. “Consciousness exists even after the brain has ceased to function. In other words, Consciousness “lives” on its own, absolutely independently. As for the brain, it is not thinking matter at all, but an organ, like any other, performing strictly defined functions. It may very well be that thinking matter does not even exist in principle,” says study leader Pim van Lommel.

The human brain is an amazingly complex formation, a delicate nervous apparatus. It is an independent system and at the same time a subsystem, included in the composition of the whole organism and functioning in unity with it, regulating its internal processes and relationships with the outside world. What facts irrefutably prove that the brain is the organ of consciousness, and consciousness is a function of the human brain?

First of all, the fact that the level of reflective-constructive ability of consciousness also depends on the level of complexity of the organization of the brain. The brain of primitive, gregarious man was poorly developed and could serve only as an organ of primitive consciousness. Brain modern man, formed as a result of long-term biosocial evolution, is a complex organ. The dependence of the level of consciousness on the degree of organization of the brain is also confirmed by the fact that the consciousness of a child is formed, as is known, in connection with the development of his brain, and when the brain of a very old man becomes decrepit, the functions of consciousness also fade away.

A normal psyche is impossible without a normally functioning brain. As soon as the refined structure of the organization of brain matter is disrupted, and even more so, destroyed, the structures of consciousness are also destroyed. When the frontal lobes are damaged, patients are unable to produce and implement complex behavioral programs; they do not have stable intentions and are easily excited by side stimuli. When the occipito-parietal parts of the cortex of the left hemisphere are damaged, orientation in space, handling of geometric relationships, etc. are impaired. It is known how the spiritual world of a person is deformed, and how complete degradation often occurs if a person systematically poisons his brain with alcohol and drugs.

Experimental data from various sciences, such as psychophysiology, physiology of higher nervous activity, etc., irrefutably indicate that consciousness is inseparable from the brain: it is impossible to separate thought from the matter that thinks. The brain with its complex biochemical, physiological, and nervous processes is the material substrate of consciousness. Consciousness is always connected with these processes occurring in the brain and does not exist apart from them. But they do not constitute the essence of consciousness. The reflection of things, their properties and relationships in the brain, of course, does not mean their movement into the brain or the formation of their physical imprints in it like imprints on wax. The brain does not become deformed, does not turn blue, or become cold when it is exposed to hard, blue and cold objects. The experienced image of an external thing is something subjective, ideal. It is not reducible either to the material object itself, located outside the brain, or to those physiological processes that occur in the brain and give rise to this image. The ideal is nothing more than the material, “transplanted” into human head and transformed in it.

The spiritual world of man cannot be touched, seen, heard, or detected by any instruments or chemical reagents. No one has yet directly found a single thought in the human brain: a thought that is ideal has no existence in the physical and physiological sense of the word. At the same time, thoughts and ideas are real. They exist. Therefore, an idea cannot be considered something “invalid”. However, its reality, reality is not material, but ideal. This is our inner world, our personal, individual consciousness, as well as the entire world of the “transpersonal” spiritual culture of humanity, that is, externally objectified ideal phenomena. Therefore, it is impossible to say which is more real - matter or consciousness. Matter - objective, and consciousness - subjective reality.

Consciousness belongs to man as a subject, and not to the objective world. There are no “anyone’s” sensations, thoughts, feelings. Every sensation, thought, idea is a sensation, thought, idea of ​​a specific person. The subjectivity of the image is by no means an arbitrary introduction of something from the subject: objective truth is also a subjective phenomenon. At the same time, the subjective also appears in the sense of incomplete adequacy of the image to the original.

The content of the mental image of an object is determined not by the anatomical and physiological organization of a person and not by what the cognizing subject finds directly in nature on the basis of his individual experience. Its content is a synthetic characteristic of an object obtained in the course of subject-transforming activity. This opens up the fundamental possibility of an objective study of consciousness: it can be known through the forms of its identification in sensory and practical activity.

The subjective image as knowledge, as spiritual reality, and physiological processes as its material substrate are qualitatively different phenomena. Misunderstanding of this qualitative specificity gave rise to a mechanical tendency to identify them. The absolutization of the specificity of consciousness as a subjective image gives rise to a tendency to contrast the ideal and the material and bring the opposition to the complete disintegration of the world into two substances - spiritual and material.

Consciousness and the objective world are opposites that form a unity. Its basis is practice, the sensory-objective activity of people. It is precisely this that gives rise to the need for mental conscious reflection of reality. The need for consciousness, and at the same time a consciousness that gives a true reflection of the world, lies in the conditions and requirements of life itself.

41. TEACHING ABOUT TRUTH. OBJECTIVITY OF TRUTH CRITERIA OF TRUTH.

Truth is usually defined as the correspondence of knowledge to an object. Truth is adequate information about an object, obtained through sensory or intellectual comprehension or communication about it and characterized in terms of its reliability. That. truth exists as subjective reality in its information and value aspects. The value of knowledge is determined by the measure of its truth. Truth is a property of knowledge, not an object of knowledge.

Knowledge is a reflection and exists in the form of a sensory or conceptual image. An image can be not only a reflection of existing existence, but also of the past. And the future - can it be reflected? Can an idea in the form of a plan be assessed as true? Apparently not. Of course, the plan is built on the basis of knowledge. And in this sense, he relies on the truth. However, the plan is assessed in terms of expediency and feasibility, and not in terms of truth or falsity.

That. truth is defined as an adequate reflection of an object by a cognizing subject, reproducing reality as it is in itself, outside and independently of consciousness. Truth is an adequate reflection of reality in the dynamics of its speed. This gives it particular value as a predictive measurement. True knowledge gives people the opportunity to intelligently organize their practices in the present and foresee the future.

But humanity rarely achieves truth except through extremes and errors. Delusion is the content of consciousness that does not correspond to reality, but is accepted as true. Misconceptions also reflect, albeit one-sidedly, objectively, reality, and have a real source. Every fiction contains threads of reality. Misconceptions are also caused by the relative freedom to choose the paths of knowledge, the complexity of the problems being solved, and the desire to realize plans in a situation of incomplete information.

So, both epistemologists have psychological and social foundations for misconceptions. But they should be distinguished from lies as a moral and psychological phenomenon. A lie is a distortion of the actual state of affairs, with the purpose of deceiving someone. A lie can be either an invention about something that did not happen, or a deliberate concealment of something that did happen. The source of lies may be and logically incorrect thinking.

Scientific knowledge is inherently impossible without clashes of different opinions and beliefs, just as it is impossible without errors. Errors are often made during observation, measurement, calculations, judgments, and assessments. As long as a person strives forward, he wanders,” said Goethe.

Everything is much more complicated in Nuk societies, particularly in history. This includes the availability of sources and their reliability and politics.

Truth is historical. The concept of ultimate or unchangeable truth is just a ghost. Any object of knowledge is inexhaustible, it changes, has many properties and is connected by an infinite number of connections with the surrounding world. Each stage of knowledge is limited by the level of development of society, science... Scientific knowledge is therefore relative. Relates knowledge to its incompleteness and probabilistic nature. Truth is therefore relative, because it does not reflect the object completely, not in an exhaustive way. Relative truth is limited-true knowledge about something.

Absolute truths include reliably established facts, dates of events, births, deaths, etc. Absolute truth is a content of knowledge that is not refuted by the subsequent development of science, but is enriched and constantly confirmed by life.

The term absolute is applicable to any truth: since it is objective, then at the very moment it contains something absolute. And in this sense, any truth is absolutely relative. The development of any truth is an increase in moments of the absolute. The new theories are more complete and profound compared to the previous ones. But new truths do not derail old stories, but complement, specify or include them as moments of more general and deeper truths. (The theory relates to Einstein and Newtonian mechanics).

Concreteness is a property of truth, based on knowledge of real connections, the interaction of all sides of an object, the main, essential properties, trends of its development. So the truth or falsity of certain judgments may not be determined. established if the conditions of place, time... are not known, in which they are formulated. A judgment that correctly reflects an object in given conditions becomes false in relation to the same object in other circumstances (boiling water at 100 degrees).

Each object along with general features The individual is also endowed with characteristics. Because of this, along with the generalized, a specific approach to the object is also necessary: ​​there is no abstract truth, it is always concrete. For example, are the principles of classical mechanics true? Yes, but within certain limits. And so for love of truth.

What gives people a guarantee of the truth of knowledge? Descartes, Spinoza, Leibniz - the crit of truth - clarity and distinctness of thinking. Example: a square has 4 sides. However, clarity and evidence are a subject of the state of consciousness and they need support on something more durable.

Such a critique of truth as universal validity was also put forward: what is true is what corresponds to the opinion of the majority. However, let us remember Copernicus. He alone was right, and the rest were wrong.

There is also a pragmatic criterion for truth: true ideas are those that work well. (useful) What works best for us, leads us, what best suits every part of life and is compatible with the totality of our experience. If ideas about God satisfy these criteria, then they are true.

The crit of truth is sealed in practice. It is in practice that a person must prove the truth, i.e. the reality of your thinking. One of the principles of thinking is that something is true if it can be proven that it applies in a particular situation. This principle is expressed in the term realizability. Through the implementation of an idea in practical action, knowledge is measured and compared with its object, thereby revealing the real measure of objectivity, the truth of its content.

As a criterion of truth, practice is not only an objective activity. It also appears in indirect form - as logic, tempered in the crucible of practice. We can say that logic is mediated pactiak. Our mind is disciplined by the logic of things, reproduced in the logic of practical actions and the entire system of the spirit of culture.

We must not forget that practice cannot completely confirm or refute any preconception or knowledge. “The atom is indivisible” - this was believed for many centuries and practice confirmed this. Practice remains silent regarding what is beyond its historically limited capabilities. However, it is constantly developing and improving. In the process of developing true knowledge and increasing its volume, science and practice increasingly appear in an inseparable unity.