A reflex understanding of mental activity is a necessary connecting link between the recognition of mental activity as the activity of the brain, inseparable from it, and understanding it as a reflection of the world. By reflex understanding of the activity of the brain, these two fundamental provisions are combined into one inseparable whole. The mental activity of the brain is, at the same time, a reflection of the world because the very activity of the brain is reflex in nature, due to influences outside world.

The reflex understanding of the mental activity of the brain suggests that it is determined by the objective world and is reflective in relation to it. At the same time, knowledge of the world by a person can be carried out only due to the fact that the functioning of the brain does not consist in simple reception of the influences falling on it, but in activity - in the analysis and synthesis, differentiation and generalization of these influences. The internal logic of the reflection theory necessarily leads to a reflex understanding of mental activity.

Just as the internal logic of the reflection theory of dialectical materialism naturally leads to a reflex understanding of brain activity, so the reflex theory of brain activity naturally leads to an understanding of mental activity as reflective.

The reflex theory of brain activity is, first of all, a statement about its determination. The recognition of mental activity as a reflex activity of the brain means not reducing mental activity to nervous, physiological, but extending the reflex concept to mental activity. The reflex theory is, at the same time, ultimately, nothing more than the extension of the principle of determinism to the activity of the brain.

The affirmation of the reflex theory of mental activity in the present work means, in fact, nothing more than the extension of the principle of determinism in its dialectical materialistic understanding to the reflective activity of the brain, to mental phenomena. A certain understanding of determinism corresponds to the corresponding understanding of the reflex theory. The reflex theory of Descartes and his immediate successors was nothing more than an extension of mechanistic determinism to the activity of the brain, the theory of cause as an external impulse. The reflex theory is essentially different, which corresponds to the dialectical-materialistic understanding of the determination of phenomena, their universal interconnection, their interaction. THEM. Sechenov and I.P. Pavlov laid the foundation for the construction of such a reflex theory.

We preface the analysis of the reflex understanding of mental activity and the determination of mental phenomena here. historical sketch dedicated to the teachings of I.M. Sechenov and I.P. Pavlova.

Neither I.M. Sechenov, nor I.P. Pavlov, whose worldview was formed under the influence of Russian revolutionary democrats, did not proceed in their scientific work from Marxist philosophy. However philosophical analysis of the reflex theory they created shows that, according to its objective internal logic, it follows the path of a concrete natural-science realization in the study of the brain and its basic activities. methodological principles dialectical materialism approaches it.

The principle of the reflex, as is known, was first formulated by Descartes (although the very term "reflex" was still absent from him). The idea of ​​a reflex in Descartes bore a vivid imprint of his mechanistic worldview. Later, in the 18th century, apparently for the first time in Asperukh Montpellier, the very term “reflex” appears. Despite the fact that the concept of "reflex" in physiology has a long history, there is every reason to talk about the reflex theory, the main provisions of which were formulated by I.M. Sechenov and received further development and specific scientific implementation in the teachings of I.P. Pavlov as a fundamentally new concept. THEM. Sechenov and I.P. Pavlov created a new concept of a reflex and, what is especially important, extended the principles of the reflex theory to mental activity.

When characterizing reflex activity in general, and hence mental activity, one usually notes what was rightly emphasized by I.M. Sechenov the position that its source lies outside, that through it the relations of the organism with the outside world are carried out. However, Sechenov-Pavlov's reflex theory, in its methodological meaning, is not a mechanistic theory of an external impulse. The theory of cause as an external impetus in explaining phenomena organic life suffers an obvious collapse: the same external influence causes a different response depending on the internal state of the organism, on which these external influences fall. External causes act through internal conditions. This dialectical-materialist position is the decisive methodological basis for the construction of any scientific theory.

Without disclosing internal laws reflex activity one would have to confine oneself to purely descriptive statements that such and such an external influence was followed in such and such a case by such and such a reaction, correlating them directly according to the scheme: stimulus - reaction. This is the path of behaviorism, corresponding to the pragmatic, positivistic methodology from which its representatives now proceed.

The reflex theory of brain activity, built on the methodological basis of dialectical materialism, is a concrete expression of the general proposition that any action is an interaction, that the effect of any cause depends not only on it, but also on what it affects, that the effect of any external cause , any external conditions are carried out through internal conditions. Hence the determinism of the reflex theory in its true sense. The activity of the brain, including its mental activity, has its cause, ultimately, in an external influence. However, there is no direct mechanical relationship between the external stimulus and the response. The dependence of the response on external influence is mediated by internal conditions. (These internal conditions themselves are formed as a result of external influences. Thus, determinism in its dialectical understanding acts at the same time as historicism: it means that the effect of each momentary impact depends on what influences the organism was subjected to before, on the entire history of the given individual and species to which it belongs.) Therefore, to construct a reflex theory of brain activity

it is necessary to reveal the internal patterns of the reflex activity of the brain. Such internal laws are open I.P. Pavlov laws of irradiation and concentration of excitation and inhibition and their mutual induction.

All of them express the internal interrelationships of the nervous processes that mediate the interrelationships of the organism with the conditions of its life carried out by the brain—their influence on it and its response activity, depending on external conditions.

The mediation of the effect of external influences by internal conditions lies not only in the characteristics and role of the laws of neurodynamics, but also in the whole doctrine of the conditioned reflex activity of the cortex, since, according to this doctrine, the effect of each conditioned stimulus, entering the cortex, enters the whole system of resulting past relationship experience. As a result, the reflex response of the organism, caused by the stimulus acting at the moment, is determined not only by it, but also by the entire system of connections that it finds in a given individual. Stimuli receive a variable value, changing depending on what they signal for a given individual due to previous experience deposited in the cortex in the form of a system of conditioned neural connections. The determinism of the Pavlovian reflex theory, regardless of its individual formulations, sounding mechanistic, is a particular expression in relation to understanding the activity of the brain of the general philosophical principle of determinism in its dialectical materialistic interpretation.

The core of the reflex understanding of mental activity is the position that mental phenomena arise in the process of interaction of the individual with the world through the brain; therefore, mental processes, inseparable from the dynamics of nervous processes, cannot be isolated either from the influence of the external world on a person, or from his actions, deeds, and practical activity, the regulation of which they serve.

Mental activity is not only a reflection of reality, but also a determinant of the significance of reflected phenomena for the individual, their relationship to his needs: therefore, it serves to regulate behavior and practical activity. Evaluation of phenomena, attitude towards them are associated with the mental from its very appearance, as well as their reflection. This evaluation, which in animals is reduced to biological significance, acquires a social content in man.

The reflex theory has as its first initial natural-science premise the proposition about the unity of the organism and the environment, about the active interaction of the organism with the external world.

Already in Sechenov, the proposition not only about interconnection, about unity, but also about the active interaction of the individual with the outside world in its special biological expression - in relation to the organism and the environment, to the organism and the conditions of its life, appears with complete certainty. This provision constituted the first, general biological, prerequisite for the discovery by Sechenov of the reflexes of the brain.

Therefore, mental phenomena contain the initial prerequisites for the development of a person not only cognition as a socio-historical process of development scientific knowledge but also for socially developed ethical norms of behavior.

THEM. Sechenov formulates this position (1861) as follows: “An organism without external environment supporting its existence is impossible; therefore, the scientific definition of an organism should also include the environment that influences it ”(Sechenov I.M. Two final lectures on the significance of the so-called plant acts in animal life // Selected production. M .: Publishing house of the USSR Academy of Sciences, 1952. T 1, p. 533). Later (1878), Sechenov writes about the influence on organisms of the “environment in which they live, or, more precisely, the conditions of their existence” (Sechenov I.M. Elements of thought // Selected Philosophical and Psychological Prod. M .: Gospolitizdat , 1947. S. 412). Thus, the environment, the conditions of existence, are introduced into the very definition of the organism: at the same time, the conditions of existence are distinguished from the environment, determined by the requirements that the organism makes to the environment.

brain. Conditioned by external influences, the reflex activity of the brain is the “mechanism” through which communication with the outside world of an organism that has a nervous system is carried out.

The second, physiological, premise of the reflex theory was Sechenov's discovery of central inhibition.

The fundamental significance of the discovery of central inhibition for the construction of a reflex theory lies primarily in the fact that it was the first step towards the discovery of the internal laws of brain activity, and the discovery of these latter was a necessary prerequisite for overcoming the mechanistic understanding of reflex activity according to the "stimulus-response" scheme, according to the mechanistic theory of cause as an external impulse, allegedly unambiguously determining

reaction effect.

The proposition about the unity of the organism and the conditions of its existence and the discovery of central inhibition are the main steps on the way to "Reflexes of the brain". They directly follow each other in time: in 1861 Sechenov published an article on the significance of the plant acts of an animal organism, in which he formulates a position on the unity of the organism and the environment, in 1862 the scientist carried out his experiments, which led to the discovery of the central braking. Having completed his first capital works on central inhibition, Sechenov immediately realized his plans in the field of psychology: already in 1863 he published Reflexes of the Brain.

We can safely say that Sechenov made two great discoveries in his scientific activity: central inhibition - in the field of physiology and reflex nature mental - in the field of psychology. It is the latter that belongs to the number of those that, while relating directly to the subject of one science, at the same time go far beyond its limits, acquiring a common philosophical significance.

These two discoveries, as well as Sechenov's scientific activity in the fields of psychology and physiology of the nervous system in general, were closely connected with each other. Sechenov himself noted the role that studies in psychology and interest in the problem of will played in his discovery of central inhibition.

On the other hand, without the discovery of the latter, Sechenov could not have understood mental processes, devoid of a visible effector, motor end, as reflex processes.

Spreading reflex principle on the brain could in no way be limited to a simple transfer of the same concept to a new sphere - this transfer necessarily required significant changes in the very concept of reflex. What are the main specific features brain reflexes? The reflex of the brain is, according to Sechenov, a learned reflex, i.e. not congenital, but acquired in the course of individual development and dependent on conditions, in

Another paragraph 3 of the "Abstracts", which were attached to the thesis by IM. Sechenov “Materials for the future physiology of intoxication”, said: “The most general nature of the normal activity of the brain (since it is expressed by movement) is a discrepancy between excitation and the action it causes - movement” (Sechenov IM. Izbr. prod. 1956. Vol. II. S. 864). This means that the prehistory of Sechenov's reflex theory already, in essence, contained the denial of the "stimulus-response" scheme and the mechanistic idea of ​​the ability of an external cause (an external push) to directly determine the result of brain activity.

The first explanation for this discrepancy between the response movement and the excitation caused by an external influence was inhibition; it - internal condition, causing one or another effect of external influence.

» See: Sechenov IM. Autobiographical notes. M.: Publishing House of the Academy of Sciences of the USSR, 1952. S. 183-186. Hence the famous position of "Reflexes of the Brain": "Thought is the first two-thirds mental reflex"(Sechenov I.M. Selected Philosophical and Psychological Works. P. 155). From “the ability to delay one’s movements,” according to Sechenov, “that huge series of phenomena follows, where mental activity remains, as they say, without external expression, in the form of thought, intention, desire, etc.” (Ibid., p. 154).

which it is formed. (Expressing the same thought in terms of his theory of higher nervous activity, Pavlov will say that this is a conditioned reflex, that this is a temporary connection.)

The reflex of the brain is the connection of the organism with the conditions of its life. This feature of the brain reflex appears with complete definiteness and fundamental sharpness in Pavlov's theory of conditioned reflexes. Pavlov figuratively characterizes a conditioned reflex, a temporal connection as a temporary closure of conductor circuits between the phenomena of the external world and the reactions of the animal organism to them. Reflex activity is an activity through which an organism that has a nervous system realizes its connection with the conditions of life, all its variable relations with the outside world. According to Pavlov, conditioned reflex activity as a signaling activity is aimed at finding in a constantly changing environment "the basic conditions of existence necessary for an animal, serving as unconditional stimuli ...". In the Pavlovian concept of reflex activity as a whole, in connection with this, the central place belongs to the concept of reinforcement: that reflex activity that is “reinforced” is carried out.

The third one is necessarily connected with the first two features of the brain reflex. Being "learned", temporary, changing with changing conditions, the brain reflex cannot be determined morphologically in fixed ways once and for all.

This trend was completed and fully implemented only by Pavlov. The Pavlovian reflex theory overcame the notion that the reflex is allegedly entirely determined by the paths morphologically fixed in the structure of the nervous system into which the stimulus enters. She showed that the reflex activity of the brain (always including both unconditioned and conditioned reflexes) is a product of the dynamics of nervous processes confined to brain structures, "expressing the variable relationship of the individual with the surrounding world."

Finally, and most importantly, the brain reflex is a reflex with a "mental complication." The promotion of the reflex principle to the brain led to the inclusion of mental activity in the reflex activity of the brain. This is a fundamentally important feature of Sechenov's concept of brain reflexes.

If we adhere to I.M. Sechenov, the reflex understanding of mental activity can be expressed in two positions.

1. General scheme mental process is the same as any reflex act: like any reflex act, the mental process originates in an external influence, continues with the central nervous activity and ends with the response activity of the individual (movement, deed, speech).

See Pavlov I.P. Poly. coll. op. 2nd ed. T. III. Book. 1M.; L. 1951. S. 116. » See Ibid. Book. 2. S. 108.

Characterizing the essence of his concept in the preface to the book "Physiology of nerve centers", I.M. Sechenov wrote that he wanted "first of all to submit to the judgment of specialists an attempt to introduce into the description of central nervous phenomena physiological system in place of the anatomical one that dominates to this day, i.e. put in the forefront not the form, but the activity, not the topographic isolation of organs, but the combination of central processes in natural groups ”(Sechenov I.M. Physiology of nerve centers. M .: Publishing House of the Academy of Sciences of the USSR, 1952. P. 21).

A similar opposition of the functional dynamic concept to the anatomical and morphological concept of preformed nerve pathways is clearly seen in Sechenov and in “Elements of Thought” (Sechenov I.M. Elements of Thought // Selected Philosophical and Psychological Prod. P. 443-444).

» It was this feature of the Pavlovian reflex theory that K.M. Bykov in his report at the 18th International Congress of Physiologists in Copenhagen on August 15-18, 1950 (See: Bykov KM. Teaching about conditioned reflexes and reflex theory // Vesti. -16.

Mental phenomena arise as a result of the "meeting" of the individual with the outside world.

2. Mental activity cannot be separated from the single reflex activity of the brain. She is the "integral part" of the latter.

Thus, psychic phenomena cannot be isolated either from objective reality or from the reflex activity of the brain.

If we analyze the general meaning of these provisions, it turns out that Sechenov's reflex understanding of mental activity means that 1) mental phenomena arise in the process of interaction of an individual with the outside world, 2) they are inseparable from the material nervous activity of the brain, due to which this interaction is carried out.

In these two propositions, the reflex theory of the mental is directly connected with the propositions of dialectical materialism.

Understanding mental activity as a “meeting” of the subject with objective reality, I.M. Sechenov overcomes the "separation" of the mental not only from the material, physiological substrate, but also from the object: the reflex understanding of mental activity with this aspect of its own opposes introspectionism, the closure of mental phenomena in inner world consciousness, isolated from the external material world.

THEM. Sechenov emphasizes the real vital significance of the psychic. Sechenov characterizes the first part of the reflex act, beginning with perception, with sensual excitation, as signaling. At the same time, sensory signals supreme bodies feelings "forewarn" about what is happening in environment. In accordance with the signals entering the central nervous system, the second part of the nervous regulator carries out the movement. Sechenov emphasizes the role of "feeling" in the regulation of movement. Sensual images - the appearance of a wolf for a sheep or a sheep for a wolf, using Sechenov's examples, entail a restructuring of all the vital functions of the wolf and sheep and cause in each animal motor reactions opposite meaning. In this active role Sechenov sees its "vital meaning", its "meaning". In the ability to serve to "distinguish the conditions of action" and thus open up the possibility for actions "corresponding to these conditions", Sechenov finds "two common values", which characterize the feeling.

In Sechenov's concept of the signal meaning of feeling and its "warning" role lie the origins of Pavlovian understanding of sensations as signals of reality.

In revealing the meaning of the reflex understanding of the psyche, Sechenov renounced all attempts to deduce the content of the psyche from the nature of the brain. Defending the reflex theory in a polemic with Kavelin, Sechenov rejected, as based on a misunderstanding, Kavelin's assertion that he, Sechenov, is trying to deduce the essence of the psyche, its content from the "arrangement of nerve centers." This does not mean a certain limitation of the reflex theory, but just its inexorable consistent implementation. To try to deduce the content of the psychic from the structure of the brain would mean, in modern terms, to take the position of psycho-morphologism and inevitably slide into physiological idealism.

Recognition that the content of mental activity as a reflex activity cannot be deduced from the "nature of the nerve centers", that it is determined

"" Feeling plays essentially the same signal role everywhere" (Sechenov I.M. Physiology

nerve centers. M.: Publishing House of the Academy of Sciences of the USSR, 1952. S. 27). » Sechenoi I.M. The first lecture at the Moscow University // Izbr. prod. T. 1. S. 582. Sechenov I.M. Elements of thought. P. 416. See: Sechenov I.M. Remarks on the book of Mr. Kavelin "Problems of Psychology" // Izbr. philosophy and psychol.

prod. S. 192.

objective being and is its image - such is the cardinal position of Sechenov's reflex understanding of the psychic. The affirmation of the reflex character of the mental is naturally connected with the recognition of the mental as a reflection of being.

Thus, in whatever direction we follow the conclusions of the reflex theory of the psyche, we invariably arrive at conclusions leading to the reflection theory of dialectical materialism. Such is the case with the philosophical meaning of the reflex understanding of the psychic.

Sechenov reveals the psychological content of the reflex theory, primarily in relation to the process of cognition. This psychological content lies, in short, in the fact that mental activity is mainly the activity of analysis, synthesis and generalization. Putting forward and defending the reflex understanding of mental activity, Sechenov is far from reducing mental activity to physiological. It's about for him about something else - about how to extend the principles of the reflex theory to the study and mental activity.

Actually physiological regularities of the central cortical activity in general I.M. Sechenov was not yet known. He believed that their discovery is a matter of the distant future. These laws were discovered by I.P. Pavlov, thereby raising the reflex theory to a qualitatively new highest level. The reflex concept of brain activity, developed and enriched by Pavlov, for the first time turned into a strictly scientific physiological doctrine. In this regard, the physiological aspect of the reflex theory necessarily and naturally comes to the fore in Pavlov's works. Pavlov, at the same time, with complete certainty and utmost clarity, declares that central concept of his entire doctrine of higher nervous activity—the “conditioned reflex”—is both a physiological and a psychic phenomenon. He himself concentrated his attention on the physiological analysis of reflex activity and, although very weightily, but still only in passing, touched upon in his published works psychological aspect reflex concept.

Probably in this regard, some representatives of the doctrine of higher nervous activity, especially in last years, sought to completely exclude any psychological content from the Pavlovian reflex concept, despite the fact that Pavlov directly characterized the main object of his study - the conditioned reflex - as a phenomenon not only physiological, but also mental.

In its critical part, Sechenov's polemic with Kavelin, who defended the idea of ​​studying consciousness by the products of spiritual activity, was a struggle against the line of "objective idealism", against the path that German psychology from Wundt to Dilthey and Spranger. The study of the products of spiritual activity in isolation from the process led to a confusion of individual and public consciousness and meant the separation of the psychological from its material substrate, from the physiological, nervous activity.

To characterize the philosophical meaning of Sechenov's reflex concept, it is very instructive, in particular, that the logic of his reflex concept led him to criticize the mechanistic understanding of the cause as an external impulse and to the assertion that any action is an interaction. In the article “Objective Thought and Reality”, Sechenov notes that “in nature there is no action without reaction”, shows with a number of examples that the effect of an external influence depends not only on the body that has an impact on another, but also on this latter, and comes to a conclusion about the interaction of phenomena, a conclusion that brings him closer to the dialectical-materialistic understanding of the interdependence of phenomena.

(See: Sechenov I.M. Subject Thought and Reality // Selected Prod. T. 1. P. 48284).

So, in recent years one could hear statements that completely fence off the “strictly objective Pavlovian method” from any contact with subjective mental phenomena, such as sensations. (See: Ivanov-Smolensky A.G. Some issues in the study joint activities of the first and second signal systems // Zhurn. higher nervous activities. 1952. Vol. II. Issue. 6. S. 862-867). In the work "Interoreceptors and the doctrine of higher nervous activity". M.: Publishing House of the Academy of Sciences of the USSR, 1952) E.Sh. Hayrapetyants, in essence, proposes to exclude the concept of sensitivity from the doctrine of higher

Such an interpretation completely separates the Pavlovian doctrine of higher nervous activity from the line outlined by Sechenov; it essentially opposes Pavlov's concept of the reflex activity of the brain to Sechenov's. In fact, there are no grounds for such a contrast. Pavlov declared the impossibility of separating already “in the most complex unconditional reflexes (instincts) the physiological, somatic from the mental, i.e. from experiencing powerful emotions of hunger, sexual desire, anger, etc.” He directly called sensations, perceptions and representations "the first signals of reality", divided human types on artistic and mental, etc.

In his research, I.P. Pavlov actually took into account the mental aspect of higher nervous activity.

In order to be convinced of this, it is necessary to compare, for example, the Pavlovian interpretation of the trial and error method with the behavioristic, Thorndike's. According to Thorndike, when an animal placed in a cage solves the problem of getting food from behind bars, it all comes down to the fact that the animal makes various chaotic movements until, by accidentally opening the cage, it takes possession of the food. The entire process of solving a problem by an animal thus consists of movements and contains nothing but motor reactions.

Pavlov analyzes this process quite differently. When the monkey, in the course of previous trials, having differentiated the stick as an object certain form, so that this form has become a signal sign for getting food, a fetus, trying to reach a distant fruit with an insufficiently long stick, what happens in this case is not reduced, according to Pavlov, only to a movement that does not reach a certain point, but also includes a differentiation of the distance of the fetus from the animal and stick sizes: new features are differentiated, i.e. act in sensation (or perception) and acquire a signal value. This is the point. Therefore, Pavlov speaks of the elementary or concrete thinking of animals. In the process of action, they achieve "cognition" of reality, its reflection in sensations and perceptions. The process of sensory reflection of reality is included in all animal behavior. Without this, the behavior of animals, their adaptation to the conditions of life, is impossible, and even more so, the behavior of man, his activity. To turn off the role of sensory reflection of reality, as some interpreters of Pavlov try to do, too zealous guardians of the virginal purity of his teaching, seeking to protect him from sinful contact with anything mental, means, grossly distorting Pavlov, to reduce his position to that of Thorndike.

The interpreters of Pavlov mentioned above, of course, do not deny the presence of sensation not only in people, but also in animals. But sensations, perceptions, etc. appear to them as subjectively experienced phenomena that can only serve as indicators of certain objective physiological processes. AT scientific knowledge the latter, allegedly, are substituted for the former, which after that lose all meaning. Apparently, this is how they understand Pavlovian "imposition" of the psychic on the physiological and their merging. The attitude of these interpreters to the true teachings of Pavlov is objectively the same as the attitude of some neo-Darwinists to Darwin, who put the theory of their teacher in the Procrustean bed of dogmatic-nervous activity, replacing it with the concept of signaling. It is interesting that the same author in the messages. devoted to the same studies that he summarizes in the above book, before talking about interoreceptive sensations, more or less clearly registered by consciousness. See, for example, his article "Higher nervous activity and interoreception" (Vesti. Leningrad University, 1946. No. 4-5). He saw the main meaning and, so to speak, the "pathos" of his research in the fact that they open the way "to understanding the psychology of the subconscious" (see: Bykov K.M., Airamtyants E.Sh. psychology of the subconscious // Abstracts of reports at the meeting of physiologists in Leningrad, dedicated to the fifth anniversary of the death of IP Pavlov, Moscow, Leningrad: Izd-vo AN SSSR, 1941, pp. 3-4). » Pavlov I.P. Tsoln. coll. op. T. III. Book. 2. S. 335.

of a formally accepted scheme, erasing from it precisely that which is at the junction of various fields and conceals in itself the greatest possibilities for the further growth of science.

Such a comparison with neo-Darwinism is not only an external analogy. It touches the very essence of the matter. If we do not recognize the reflection of objective conditions in images, sensations and perceptions, then the adaptability of response actions to conditions will have to be reduced to "natural selection" adequate reactions from among those that arise randomly, selection carried out by inhibiting reactions that are not supported by reality, just as neo-Darwinism, and partly Darwinism in general, reduces the explanation of the adaptability of an organism to the environment to the natural selection of organisms. Neo-Darwinism reduces everything to the selection of organisms, being unable to explain their formation by the conditions of life. As a result, he is forced to consider this process as being entirely in the power of chance - random changes (mutations). Similarly, in a theory that separates action from the reflection of reality, the process of forming an action adapted to objective conditions is inevitably given over to the undivided power of chance. The proof is Thorndike's theory, according to which an action that meets conditions is selected from among completely random reactions, since there is no "mechanism" capable of bringing it into conformity with objective conditions in the process of the very formation of an action. This theory is an exact analogue of the theory that explains the adaptability of organisms to the conditions of their life solely by natural selection, without any consideration of the processes of metabolism between organisms and the conditions of their life that determine their formation.

Pavlov outlined a different path, fundamentally different from Thorndike's. According to Pavlov, the very process of forming an action that meets objective conditions, according to the “trial and error” method, does not act as a blind game of chance, but as natural process. Pavlov achieves this precisely by showing how, in the course of the animal's actions, analysis and synthesis, differentiation and generalization of stimuli are carried out, reflected in sensation, in the concrete "thinking" of animals.

If, concentrating on such a brilliantly solved task of the physiological analysis of reflex activity, Pavlov did not pay as much attention as Sechenov did to its psychological analysis, this does not mean that, in contrast to the latter, he ignored or even rejected the role of figurative reflection of reality in the reflex activity of the cerebral cortex. . Fundamental to the Pavlovian concept, the position that sensation, perception, representation are the “first signals of reality” is direct and indisputable evidence that they have a single line on this issue; there is not the slightest reason to oppose Pavlov to Sechenov or Sechenov to Pavlov in this matter.

Principal installations of I.M. Sechenov and I.P. Pavlova on the issue of place mental reflection in the activity of the brain are the same, they have a common line in this matter.

In this common cause, I.P. Pavlov made a contribution that can hardly be overestimated: he discovered the laws of reflex activity of the cortex - he created the doctrine of higher nervous activity.

The doctrine of higher nervous activity is a discipline bordering between

physiology and psychology; Being a physiological discipline in its method, at the same time, in its tasks it belongs to the field of psychology. Since its ultimate task is the explanation of mental phenomena (the emergence of sensations as a result of the differentiation of stimuli and the determination by means of signal connections of the meaning of objects and phenomena of reality for the life and activity of the individual), insofar as the doctrine of higher nervous activity passes into the field of psychology, but in no way exhausts it. The relation of the doctrine of higher nervous activity to psychology can be compared with the relation of biochemistry

(rather than chemistry) to biology. The Pavlovian doctrine of higher nervous activity belongs to those borderline scientific disciplines that lie at the junction of two sciences and form a transition between them, which play a leading role in modern system scientific knowledge. The role of the doctrine of higher nervous activity is especially great, since here we are talking about the transition from material physiological processes to mental ones, between which the dualistic worldview creates a gap, an abyss.

His doctrine of higher nervous activity, developed on animals, I.P. Pavlov significantly expanded in relation to man with his idea of ​​the second signal system of reality, interacting with the first and acting according to the same physiological laws as it.

Introduction to the doctrine of higher nervous activity of the second signaling system is of significant, one might say, fundamental importance, because it outlines a program for the physiological explanation of human consciousness as a product public life in its specific features.

For the second signal system, it is decisive that the stimulus in it is the word - a means of communication, a carrier of abstraction and generalization, the reality of thought. At the same time, the second signaling system, like the first, is not a system of external phenomena that serve as stimuli, but a system of reflex connections in their physiological expression; the second signaling system is not language, speech, or thinking, but the principle of cortical activity, which forms the physiological basis for their explanation. The second signaling system is not language, not the word as such, as a unit of language, but the system of connections and reactions that are formed to the word as a stimulus. The specific actual content of the concept of the second signal system lies primarily in experimental proof the fact that the word, both pronounced by a person and influencing him and perceived by him, is firmly "grounded" in all organic human life. The word spoken by a person has as its “basal component” speech-motor kinesthesias, conditioned reflexes associated with the entire activity of the cortex. The word, visible and audible, perceived by a person, is for him a real stimulus, capable of becoming stronger under certain conditions than the “primary signal” stimulus. This fact, established by physiological research, is of fundamental importance for the understanding of the whole psychology of man.

T p and interrelated features characterize the Pavlovian physiology of the brain.

1. Pavlov first created the physiology of the brain, its higher department. For the understanding of mental activity, this is of decisive importance. Before Pavlov, only sensation was subjected to physiological analysis; pre-Pavlovian physiology was the physiology of the sense organs as peripheral devices - receptors. For Pavlov, the cortex itself is a grandiose organ of sensitivity, consisting of the central cortical ends of the analyzer.

As is known, Pavlov also considers the so-called motor cortex as a motor analyzer, i.e. also as an organ of sensitivity, analyzing the signals coming from a moving organ. On the other hand, the so-called sensitive areas of the cortex inevitably perform and motor functions; because the

So, the experiments of K.M. Bykov and A.T. Pshonik showed that if, for example, a thermal stimulus-a heated plate is applied to the hand and the subject is told "cold", then, with a well-established system of appropriate conditioned connections, the subject's vascular reactions will follow the verbal stimulus in spite of the direct stimulus (See: Bykov K .M., Pshonik A.T. On the nature of the conditioned reflex // Physiological Journal of the USSR, 1949. V. XXXV, No. 5. P. 509-523. Function of an organism, Moscow, 1952.

the activity of the cortex is reflex, its final link is motor effect reactions. This proposition necessarily follows from all the works of Pavlov and his school, which show that the activity of the cortex has a reflex character. The idea of ​​the cortex as an organ of sensitivity, as a set of central cortical ends of the analyzers, overcomes the isolation of the peripheral receptor as an organ of sensitivity. In this way, it leads to the overcoming of the idealistic theory of sensation by Müller-Helmholtz and creates the prerequisites for the elimination of the gap between sensation, on the one hand, and perception and thinking, on the other. The same situation is overcome not only by the isolation of the peripheral receptor from the central cortical instruments, but also by the isolation of the central cortical instruments of the cerebral cortex from influences on peripheral receptors. Thus, the entire activity of the brain is placed under the control of the influences of the external world and excludes the idealistic idea of ​​supposedly purely "spontaneous" activity of the brain.

The concept of the cortex, which comes from the theory of analyzers, is a necessary prerequisite for the realization of the reflex principle in all brain activity. It is easy, therefore, to understand the full significance of such a conception of the cortex.

The difference between the concepts of brain physiology and peripheral physiology of the sense organs is fundamental.

The Physiology of the Sense Organs, which limited its competence to elementary forms of sensitivity, left full scope for an idealistic interpretation of all "higher" mental processes. Physiology of the Brain excludes this possibility.

It is not for nothing that the American behaviorists, who openly oppose Pavlov's teachings (as, for example, Gasri), or disguise themselves, classifying themselves as members of the "neo-Pavlovian" school (for example, Hull and his followers), direct their efforts precisely to ensure that the very Pavlovian concepts of excitation, inhibition , irradiations, etc., meaning in I.P. Pavlova, the central and cortical processes, to present as peripheral phenomena. They use the same peripheral concept that Müller and Helmholtz carried out in their study of the receptor functions of the sense organs. The peripheral, mechanistic understanding of the “conditioning” of reactions, which is substituted for the Pavlovian teaching, in its apparent inability to explain complex shapes behavior directly leads to building over them more and more frank idealistic concepts of behavior, allegedly based on "insight", etc.

2. The physiology of the brain differs from the peripheral physiology of receptors and effectors not only in where, according to one and the other theory, the main activity of the nervous apparatus is carried out, but also in what it consists of. And this is the main point. According to the peripheral theory, the role of the brain is reduced to elementary functions simple transfer of excitation from the receptor to the effector; peripheral devices - receptors and effectors - obviously cannot perform the functions that, according to Pavlov, are performed by the brain, the cortex.

Research by Pavlov and his school showed that the brain produces complex analysis and synthesis, differentiation and generalization of stimuli. It is in this - analysis and synthesis, differentiation and generalization - that the higher nervous, or mental activity of the brain consists. Through analysis, synthesis, etc. and the relationship of the organism, the individual with the outside world is carried out. At the same time, the (higher) analysis carried out by the cortex is an analysis of stimuli not only in terms of their composition, but also in terms of their significance for the organism. That is why Pavlovian physiology is the physiology of behavior-activity, through which the relationship of the individual, the organism with the environment is carried out, and not just the reaction of a separate organ - the effector (as in the American representatives of the doctrine of conditioning).

3. The object of Pavlov's study was the unified holistic activity of the cortex - the higher part of the brain, the higher nervous activity, both physiological and mental. This single higher nervous activity of I.P. Pavlov subjected consistently to physiological research. The task of his research is to give this higher nervous, i.e. materialistically understood mental activity, physiological explanation. To do this, he turns to the study of the dynamics of those nervous processes through which the reflex activity of the cortex is carried out - analysis, synthesis, differentiation and generalization of stimuli - and builds his "real" (as he himself qualifies it) physiology of the higher part of the brain.

Excitation and inhibition - their irradiation, concentration and mutual induction - these are the physiological processes through which analysis, synthesis, etc. are carried out. The function that these processes perform is reflected in the very physiological characteristics of cortical processes and their dynamics. The change in the basic processes, excitation and inhibition, is subject to the task in the resolution of which they are included - to carry out the relationship of the individual with the conditions of his life. This is most clearly seen in the fact that physically one and the same stimulus can turn from the stimulus of a certain reaction into its brake if this reaction has not received "reinforcement". This means that the very property of the stimulus to be the stimulus or inhibitor of certain reactions depends on the behavioral effect of the reaction to it. This very clearly and sharply expresses the most important proposition that it is impossible to understand the activity of the brain outside the interaction of the individual with the surrounding world, without taking into account both the influence of the world on the brain and the response of the individual.

At the same time, all Pavlovian laws of nervous processes are internal, i.e. specific physiological laws. The laws of irradiation, concentration and mutual production determine the internal relationships of nervous processes to each other. These internal relations nervous processes to each other and the internal laws that express them mediate all the responses of the individual to external influences. It is thanks to the discovery of these internal laws of brain activity, which mediate the effect of all external influences, that the determinism of Pavlov's reflex theory acquires a dialectical-materialistic rather than a mechanistic character. If there were no such internal laws that determine the internal relationships of the nervous cortical processes to each other, there would be no physiology of the brain as a science.

Analysis of the teachings of I.P. Pavlov about higher nervous activity allows, as well as the analysis of the works of I.M. Sechenov, to isolate from their special natural-science content the fundamental philosophical framework of the reflex theory. The most general and fundamental content of the reflex theory, isolated from the works of I.M. Sechenov and I.P. Pavlov, can be briefly formulated in the following provisions.

1. Mental phenomena arise in the process of interaction of an individual with the outside world.

2. Mental activity, during which mental phenomena arise, is the reflex activity of the nervous system, the brain. Reflex theory I.M. Sechenov-I.P. Pavlova concerns not only physiological foundations mental activity, but also itself.

Psychic activity as reflexive, reflective is an analytical-synthetic activity.

3. Due to the reflex nature of mental activity, mental phenomena are a reflection of the reality that affects the brain.

“We ... having left physiology, we all the time strictly adhere to the physiological point of view and study and systematize the whole subject only physiologically” (Pavlov I.P. Complete collection of works. Vol. IV. P. 22).

4. The reflective activity of the brain is determined by external conditions acting through internal ones.

Thus, from the specific natural science content of the reflex theory, a general theoretical core is singled out, which, according to its internal logic, according to its objective methodological meaning (regardless of the personal views of I.M. Sechenov and I.P. Pavlov in their historical conditionality) naturally leads to the theory of reflection and determinism in their dialectical materialistic understanding. It is precisely because of this that the reflex theory, which implements these general principles in the concrete natural-science content of the doctrine of the activity of the brain, has acquired such fundamental significance for Soviet psychology. However, it is necessary to distinguish between a special form of manifestation of general philosophical principles, in which they act in the reflex theory of brain activity as a physiological doctrine of higher nervous activity, and these philosophical principles themselves. Otherwise, it creates the possibility of substituting a particular form of manifestation of philosophical propositions in place of these latter. Thus, what is the content of a proper philosophical theory is transferred to the reflex theory of brain activity as a theory of natural science, and the role of this latter is masked. And so it turns out that the principle of determinism now often appears for psychologists as one of the provisions of the reflex theory in the doctrine of higher nervous activity, while in reality the reflex theory itself is a particular expression of the principle of determinism of dialectical materialism.

The danger and harm of such a substitution in place of the general philosophical principle of a special form of its manifestation in one or another particular science, in this case in the doctrine of higher nervous activity, lies in the false position that such a substitution creates for other, related sciences - in this case for psychology. This latter is faced with a false alternative: either not to implement this principle at all, or to accept it in that special form its manifestation, which is specific to another science; meanwhile, the real task of every science, including psychology, is to find for the initial philosophical principles common to a number of sciences a form of manifestation specific to the given science. The generality of principles, which, in this way, would appear in their own way in the doctrine of higher nervous activity and psychology, is the only reliable basis for psychology to "overlap" the doctrine of higher nervous activity and close with it without prejudice to the specifics of each from these sciences. Summing up, we must be clear about the following.

1. In the real construction of his doctrine of higher nervous activity, I.P. Pavlov, having discovered the internal physiological laws of neurodynamics, made of the greatest importance a step that actually leads to the realization of the dialectical materialist position, according to which external causes act through internal conditions.

2. This general methodological side of the issue is inextricably linked with the specific, factual. One cannot think that the “mechanisms” discovered by I.P. Pavlov and his school completely, completely explain the activity of human consciousness, not only in general, but also in its specific features. To think in this way means to methodologically stand on mechanistic positions, to reduce the specific to the general. Often in recent times encountered attempts to explain all phenomena by means of all the same schemes without any development, concretization, changes threaten to give the operation of Pavlovian teaching or, more precisely, Pavlovian terms and schemes a touch of verbality and formalism. When verbalism or formalism mindlessly churns out the same formulas various phenomena, regardless of their specificity, it ceases to be only thoughtlessness or personal helplessness of this or that researcher. When it is associated with the tendency to absolutize what has already been achieved in science and turn its concepts into universal ones.

master keys, it becomes a symptom of trouble in science and a threat to its further development. No matter how great what has already been achieved, it should not close the way for further research, the discovery of ever new “mechanisms” for explaining new phenomena in their specific features, in particular, the specific features of ever higher forms of mental activity. Least of all is this an underestimation of the general provisions of the reflex theory; just here we have taken the generalization of the principle of reflexivity to its limit - to its coincidence with general principle determinism; in this general form it is universal and extends to all phenomena. This is not about denying or belittling the significance of the principles of the Pavlovian reflex theory, but about formal use results relating to investigated and really explained phenomena, do not close the way for further research and a genuine, rather than verbal explanation of the specific features of not yet studied higher forms. Fetishization of what has already been achieved and stagnation in science are inseparable,

Genuine science does not stand still; it, like a human thought, is in in constant motion. She knows only temporary parking. She is always on the go. Everything that has already been done is a stage on this path, only a stepping stone for further deepening into the essence of phenomena and climbing to new heights of knowledge.

REFLECTOR THEORY OF BEHAVIOR. Reflex is the main form of activity of the nervous system. The simplest reflexes belong to the innate, or unconditioned; they are inherited and ensure the adaptation of the body to constant environmental conditions. Without conditioned reflexes refer to the species characteristics of animal behavior. Already in a newborn child, the simplest unconditioned reactions are observed: sucking (food unconditioned reflex), blinking eyes (defensive unconditioned reflex), reflex, “what is it?” (orienting unconditioned reflex).

More complex forms of innate behavior are called instincts.

In the conditions of the external world, which is constantly changing, in addition to unconditioned reflexes, each individual organism has its own, individual experience. Same unconditioned reflexes can be performed both in response to hereditarily given stimuli, and to those signals that a given organism encounters only in its individual life. Such reflexes are called conditional.

Conditional reflexes are reactions acquired during the life of each person, with the help of which her body adapts to the changing influences of the environment. Conditioned reflexes are not inherited, but are acquired in the process of learning. A conditioned reflex is formed when some external event coincides in time with one or another activity of the organism or is reinforced by an unconditioned reflex.

During life, many complex conditioned reflexes are produced, which become part of our life experience. Motor conditioned reflexes that are produced by a person throughout life are called skills, or automated actions, with the help of which a person masters new motor skills, produces new forms of behavior.

Consequently, our behavior is determined by: 1) internal needs and 2) specific external conditions to which we constantly adapt with the help of unconditioned and conditioned reflexes. Consequently, our behavior is not only active and purposeful, but also subtly and precisely adapted to the surrounding conditions.

ADAPTIVE CHARACTER OF BEHAVIOR. For the normal existence of an organism in a changeable external environment, it is necessary to change its behavior in time, to adapt it to specific conditions.

The ability to manage one's behavior, change it in time, and sometimes completely restrain certain behavioral reactions is one of the “important features of a well-mannered person.

Distinguish between unconditioned inhibition (when the unconditioned orienting reflex inhibits the corresponding behavior) and conditioned inhibition (when the conditioned reflex gradually fades as a result of its non-stimulation by the unconditioned stimulus). Those conditional reflexes and skills that cease to be of vital importance for a person or are not reinforced, go out. Instead, in the process of learning, other forms of behavior (conditioned reflexes) are produced that better adapt the human body to environmental conditions.

Reflex theory and its basic principles

The provisions of the reflex theory developed by I. M. Sechenov. I. P. Pavlov and developed by N. E. Vvedensky. A. A. Ukhtomsky. V. M. Bekhterev, P. K. Anokhin and other physiologists are the scientific and theoretical basis of Soviet physiology and psychology. These positions find their creative development in the studies of Soviet physiologists and psychologists.

The reflex theory, which recognizes the reflex essence of the activity of the nervous system, is based on three main principles:

1) the principle of materialistic determinism;

2) the principle of structure;

3) the principle of analysis and synthesis.

Principle of materialistic determinism means that each nervous process in the brain is determined (caused) by the action of certain stimuli.

Structural principle lies in the fact that the differences in the functions of different parts of the nervous system depend on the features of their structure, and the change in the structure of parts of the nervous system in the process of development is due to a change in functions. Thus, in animals that do not have a brain, the higher nervous activity is much more primitive than the higher nervous activity of animals that have a brain. In humans, in the course of historical development, the brain has reached especially complex structure and perfection that is associated with it labor activity and social conditions life, requiring constant verbal communication.

Principle of analysis and synthesis is expressed as follows. When centripetal impulses enter the central nervous system, excitation occurs in some neurons, inhibition occurs in others, i.e., a physiological analysis occurs. The result is the distinction between specific objects and phenomena of reality and processes occurring inside the body.

At the same time, during the formation of a conditioned reflex, a temporary neural connection(closure) between two centers of excitation, which physiologically expresses a synthesis. The conditioned reflex is the unity of analysis and synthesis.

Reflex - a concept, its role and significance in the body

Reflexes (from the Latin slot reflexus - reflected) are the body's responses to irritation of receptors. In the receptors there are nerve impulses, which through sensory (centripetal) neurons enter the central nervous system. There, the received information is processed by intercalary neurons, after which motor (centrifugal) neurons are excited and nerve impulses actuate the executive organs - muscles or glands. Intercalary neurons are called neurons, the bodies and processes of which do not go beyond the central nervous system. The path along which nerve impulses pass from the receptor to the executive organ is called the reflex arc.

Reflex actions are holistic actions aimed at satisfying a specific need for food, water, security, etc. They contribute to the survival of an individual or species as a whole. They are classified into food, water-producing, defensive, sexual, orienting, nest-building, etc. There are reflexes that establish a certain order (hierarchy) in a herd or flock, and territorial reflexes that determine the territory captured by one or another individual or flock.

There are positive reflexes, when the stimulus causes a certain activity, and negative, inhibitory, in which the activity stops. The latter, for example, include the passive-defensive reflex in animals, when they freeze at the appearance of a predator, an unfamiliar sound.

Reflexes play an exceptional role in maintaining constancy internal environment organism, its homeostasis. So, for example, with an increase in blood pressure, a reflex slowdown of cardiac activity and an expansion of the lumen of the arteries occur, so the pressure decreases. With its strong fall, opposite reflexes arise, strengthening and speeding up the contractions of the heart and narrowing the lumen of the arteries, as a result, the pressure rises. It continuously fluctuates around a certain constant value, which is called the physiological constant. This value is genetically determined.

The famous Soviet physiologist P. K. Anokhin showed that the actions of animals and humans are determined by their needs. For example, the lack of water in the body is first replenished by internal reserves. There are reflexes that delay the loss of water in the kidneys, the absorption of water from the intestines increases, etc. If this does not lead to the desired result, excitation occurs in the centers of the brain that regulate the flow of water and a feeling of thirst appears. This arousal causes goal-directed behavior, the search for water. Thanks to direct connections, nerve impulses going from the brain to the executive organs, the necessary actions are provided (the animal finds and drinks water), and thanks to feedback, nerve impulses going in the opposite direction - from peripheral organs: the oral cavity and stomach - to the brain, informs the latter about the results of the action. So, while drinking, the center of water saturation is excited, and when the thirst is satisfied, the corresponding center is inhibited. This is how the controlling function of the central nervous system is carried out.

A great achievement of physiology was the discovery by IP Pavlov of conditioned reflexes.

Unconditioned reflexes are inborn, inherited by the body reactions to environmental influences. Unconditioned reflexes are characterized by constancy and do not depend on training and special conditions for their occurrence. For example, the body responds to pain irritation with a defensive reaction. There is a wide variety of unconditioned reflexes: defensive, food, orientation, sexual, etc.

The reactions that underlie unconditioned reflexes in animals have been developed over thousands of years in the course of adaptation of various animal species to the environment, in the process of struggle for existence. Gradually, under conditions of long evolution, the unconditioned reflex reactions necessary to satisfy the biological needs and preserve the vital activity of the organism were fixed and inherited, and those of the unconditioned reflex reactions that lost their value for the life of the organism lost their expediency, on the contrary, disappeared. not recovering.

Under the influence of a constant change in the environment, more durable and perfect forms of animal response were required to ensure the adaptation of the organism to the changed conditions of life. In the process of individual development, highly organized animals form a special type of reflexes, which IP Pavlov called conditional.

Conditioned reflexes acquired by an organism during its lifetime provide an appropriate response of a living organism to changes in the environment and, on this basis, balance the organism with the environment. Unlike unconditioned reflexes, which are usually carried out by the lower parts of the central nervous system (spinal cord, medulla oblongata, subcortical nodes), conditioned reflexes in highly organized animals and humans are carried out mainly by the higher part of the central nervous system (cerebral cortex).

The observation of the phenomenon of "psychic secretion" in a dog helped IP Pavlov discover the conditioned reflex. The animal, seeing food at a distance, intensively salivated even before the food was served. This fact has been interpreted in different ways. The essence of "mental secretion" was explained by IP Pavlov. He found that, firstly, in order for a dog to start salivating at the sight of meat, it had to see and eat it at least once before. And, secondly, any stimulus (for example, the type of food, a bell, a flashing light, etc.) can cause salivation, provided that the time of action of this stimulus and the time of feeding coincide. If, for example, feeding was constantly preceded by the knock of a cup in which there was food, then there always came a moment when the dog began to salivate just at one knock. Reactions that are caused by stimuli that were previously indifferent. I. P. Pavlov called conditioned reflex. The conditioned reflex, I. P. Pavlov noted, is a physiological phenomenon, since it is associated with the activity of the central nervous system, and at the same time, a psychological one, since it is a reflection in the brain of the specific properties of stimuli from the outside world.

Conditioned reflexes in animals in the experiments of I. P. Pavlov were most often developed on the basis of an unconditioned food reflex, when food served as an unconditioned stimulus, and one of the stimuli (light, sound, etc.) indifferent (indifferent) to food served as the conditioned stimulus. .).

There are natural conditioned stimuli, which serve as one of the signs of unconditioned stimuli (the smell of food, the squeak of a chicken for a chicken, which causes a parental conditioned reflex in it, the squeak of a mouse for a cat, etc.), and artificial conditioned stimuli that are completely unrelated to unconditioned reflex stimuli. (for example, a light bulb, to the light of which a salivary reflex was developed in a dog, the ringing of a gong, on which moose gather for feeding, etc.). However, any conditioned reflex has a signal value, and if the conditioned stimulus loses it, then the conditioned reflex gradually fades away.

Reflex principle construction of the nervous system Feedback principle

From point of view modern science the nervous system is a collection of neurons connected by synapses into cell chains that act on the principle of reflection, that is, reflexively. Reflex (from Latin reflexus - “turned back”, “reflected”) - the body's reaction to irritation, carried out with the help of the nervous system. The first ideas about the reflected activity of the brain were expressed in 1649 by the French scientist and philosopher Rene Descartes (1590-1650). He considered reflexes as the simplest movements. However, over time, the concept has expanded.

In 1863, the creator of the Russian school of physiologists, Ivan Mikhailovich Sechenov, uttered a phrase that went down in the history of medicine: "All acts of conscious and unconscious activity are, by way of origin, reflexes." Three years later, he substantiated his claim in the classic Reflexes of the Brain. Another Russian scientist I. P. Pavlov built on the statement of a brilliant compatriot the doctrine of higher nervous activity. The reflexes underlying it, Pavlov divided into unconditional, with which a person is born, and conditional, acquired during life.

The structural basis of any reflex is the reflex arc. The shortest consists of three neurons and functions within the torso. It turns on when the receptors are irritated (from Latin recipio - “take”); they are sensitive nerve endings or special cells that convert this or that effect (light, sound, etc.) into biopotentials (from the Greek "bios" - "life" plat. potentia - "strength").

Through centripetal - afferent (from Latin affero - “I bring”) fibers, signals arrive at the so-called first (sensitive) neuron located in the spinal ganglion. It is he who passes through himself the initial information, which the brain transforms in a fraction of a second into familiar sensations: touch, prick, warmth ... Along the axon of a sensitive nerve cell, impulses follow to the second neuron - intermediate (intercalary). It is located in the posterior sections, or, as experts say, the posterior horns of the spinal cord; a horizontal section of the spinal cord really looks like the head of a strange animal with four horns.

From here, the signals have a direct road to the anterior horns: to the third - motor - neuron. The axon of the motor cell extends beyond the spinal cord along with other efferent (from Latin effero - “I take out”) fibers as part of the nerve roots and nerves. They transmit commands from the central nervous system to the working organs: the muscle, for example, is ordered to contract, the gland - to secrete juice, the vessels - to expand, etc.

However, the activity of the nervous system is not limited to the “highest decrees”. She not only gives orders, but also strictly monitors their execution - she analyzes signals from receptors located in the organs that work on her instructions. Due to this, the amount of work is adjusted depending on the state of the “subordinates”. In fact, the body is a self-regulating system: it carries out vital activity according to the principle of closed cycles, with feedback on the result achieved. Academician Pyotr Kuzmich Anokhin (1898-1974) came to this conclusion back in 1934, when he combined the theory of reflexes with biological cybernetics.

Sensory and motor neurons are the alpha and omega of a simple reflex arc: it starts with one and ends with another. In complex reflex arcs, ascending and descending cell chains are formed, connected by a cascade of intercalary neurons. This is how extensive bilateral connections are made between the brain and the spinal cord.

The formation of a conditioned reflex connection requires a number of conditions:

1. Multiple coincidence in time of the action of the unconditioned and conditioned stimuli (more precisely, with some precedence of the action of the conditioned stimulus). Sometimes a connection is formed even with a single coincidence of the action of stimuli.

2. Absence of extraneous irritants. The action of an external stimulus during the development of a conditioned reflex leads to inhibition (or even cessation) of the conditioned reflex reaction.

3. Greater physiological strength (factor of biological significance) of the unconditioned stimulus in comparison with the conditioned stimulus.

4. Active state of the cerebral cortex.

According to modern concepts, nerve impulses are transmitted during the implementation of reflexes along the reflex rings. The reflex ring includes at least 5 links.

It should be noted that the latest research data of scientists (P.K. Anokhin and others) confirm just such an annular reflex scheme, and not a reflex arc scheme that does not fully reveal this complex process. The body needs to receive information about the results committed action, information about each stage of the ongoing action. Without it, the brain cannot organize purposeful activity, cannot correct the action when any random (interfering) factors intervene in the reaction, cannot stop the activity at the necessary moment, when the result is achieved. This led to the need to move from the idea of ​​an open reflex arc to the idea of ​​a cyclic innervation structure in which there is feedback - from the effector and the object of activity through receptors to the central nervous structures.

This connection (the reverse flow of information from the object of activity) is a mandatory element. Without it, the organism would be cut off from the environment in which it lives and to change which its activity is directed, including human activity associated with the use of tools of production.



The rapid development of physiology and biology, discoveries in psychophysics and psychophysiology also stimulated the development of an anatomical and morphological model of the reflex, which filled the rather speculative concepts of Descartes and Hartley with real content.

In the works of the psychophysiologist and physician I. Prochazka, a “common sensory” was discovered - an area of ​​the brain where nerves originate, the irritation of which causes a transition from sensation to a motor response of the body to an external impulse, i.e. from sensitive (sensory, centripetal) nerves to motor (motor, centrifugal). The lower levels of innervation of behavior, which I wrote about, are not associated with the work of the brain, but of the spinal cord, which is involved in the organization of elementary forms of behavior, a kind of automatisms, which, however, do not act purely mechanically, but in accordance with the biological needs of the organism.

The study of the reflex system was continued in the works of the English anatomist and physiologist C. Bell and the French scientist F. Magendie, who identified the fibers that go from the roots through the spinal cord to the fibers that actuate the muscular apparatus. Thus, the reflex model was defined as a kind of automaton, consisting of three blocks: centripetal, central and centrifugal. This anatomical and morphological model of the work of the central nervous system was called the Bell-Magendie law. This law describes the distribution pattern nerve fibers in the roots of the spinal cord: sensory fibers enter the spinal cord as part of the posterior roots, and motor fibers enter the anterior roots.

Research by I.M. Sechenov systematized the previous concepts, transforming the reflex system in accordance with the experimental data of physiology. In the structure of the analyzer, he singled out three parts - centripetal, i.e. receptor, central part, processing information, and centrifugal, transmitting signals to the muscle. An important point for the modern understanding of the reflex is the image put forward by Sechenov - a signal that not only "triggers" the reflex, but also regulates its course. In other words, not an external stimulus, but its reflection in the sense organ is a signal that triggers a reflex act. At the same time, a signal (i.e., an image of an object or situation), which makes it possible to distinguish the properties of objects in the external environment, directs and corrects the course of the reflex, optimizing its course.

In the central part, several information processing centers are distinguished, the main of which are: the center of inhibition (volitional regulation), information storage (memory), pre-notification (thinking) and signal amplification (emotions).

Having put forward the principle of "coordination of movement with feeling," Sechenov fundamentally reconsidered the role of muscular efforts in the reflex act. His idea that the muscular sense contains a system of signals about the spatio-temporal parameters of the external world has been proven by a significant number of works. modern psychologists and physiologists. Thus, the muscle is not only an organ of movement, but also an organ of cognition, since objective actions are external analogues of some mental operations (analysis, synthesis, classification, etc.), helping to develop internal, proper mental operations.

Sechenov's thoughts about feedback (i.e., signals from the muscle to the sense organs), for self-regulation of behavior, were developed by N.A. Bernstein, who studied the mechanisms of movement construction.

Bernstein showed that automatic execution by muscles of commands sent by nerve centers cannot underlie a complex movement, since it is continuously corrected in the process of execution. This is due to the fact that there is a cyclic connection between the muscle and the center. From the centers, signals are sent to the periphery in advance (Bernstein called them sensory corrections), which reflect, in accordance with the changing situation, the final result.

That is, the body, working, solves the motor problem. At the same time, there are five various levels movement building. Each level has its own, in his language, "afferent syntheses". This means that in the nerve centers there is, as it were, encoded information that carries information in advance about the outside world, in the space of which this or that class of movements is to be performed - “advanced reflection”. Thanks to this, the body is able to anticipate, predict the conditions in which it will have to act in the future, and not only store information about the past and respond to stimuli that affect its nervous system at the moment.

The organism faces the world already having a stock of projects of possible movements. In the creation of these projects, the activity of the organism is manifested, the ability to be creative, to create something new, to build, as Bernstein wrote, a model of the “required result”. Thus, the reflex model was finally formulated, while the most important reason for the activity was not direct action stimulus to the organs of its perception, but a blank model of a possible future action.

In addition to the structure of the reflex act, scientists were also interested in the ways of its transformation, changes under the influence of training and education. The works of I.P. Pavlov and V.M. Bekhterev.

Having studied the regularities of the dynamics of nervous processes (inhibition, irradiation, concentration, etc.), which determine external manifestations behavior, scientists have identified two levels of reflex behavior - unconditioned (simple) and conditioned (or combination) reflexes. Having a biological basis, the conditioned reflex is formed on the basis of an innate, unconditional (certain need, for example, for food, protection from harmful effects and others), and the body is constantly learning to distinguish, differentiate signals. If the signal leads to success, i.e. is reinforced, a connection is formed between it and the response action of the organism, which, with repetition, becomes more and more strong. This is how a conditioned reflex arises and is fixed.

The orienting reflex discovered by Pavlov, or, as he called it, the “What is it?” reflex, was also of great importance. It lies in the fact that the organism, as it were, continuously asks this question to the world around it, trying to find out the meaning of the situation in which it finds itself, and in the best way to “calculate” what is of the greatest value to it. The orienting reflex not only helps adaptation in an unfamiliar environment, but is also biological basis any cognitive motivation, stimulating interest in unfamiliar, new stimuli.

Exploring biological mechanisms reflex activity, Bekhterev proved that the flexibility and plasticity of the nervous system makes it possible to change in the right direction reflexes of any degree of complexity. That is, in the behavior of living beings, inherited reflexes play a minimal role, while the leading one belongs to acquired, conditional ones.

Reflex is the main form of nervous activity. It reflects the basic principle of the relationship between the body and the environment, linking them into a single system, and the idea of ​​a reflex arc explains the mechanism of this relationship.

The main provisions of the reflex principle of the activity of the central nervous system were developed over a period of about two and a half centuries. There are five main stages in the development of this concept.

First stage- the foundations for understanding the reflex principle of CNS activity were laid by the French naturalist and mathematician R. Descartes (XVII century). Descartes believed that "all things and phenomena can be explained by natural science." This starting position allowed him to formulate two important provisions of the reflex theory: 1) the activity of the body under external influence is reflected (later it was called reflex: lat. reflexus - reflected), 2) the response to irritation is carried out with the help of the nervous system. According to Descartes, nerves are tubes through which animal spirits, material particles move at great speed. unknown nature, along the nerves they enter the muscle and the muscle swells (contracts).

Second phase- experimental substantiation of materialistic ideas about the reflex (XVII-XIX centuries), which was developed by the Czech researcher T. Prochazka, who significantly expanded the doctrine of reflective actions. In particular, it was found that the reflex reaction in spinal animals occurs in response to irritation of certain areas of the skin, i.e. can be carried out on one frog metamere (segment of the spinal cord associated with a "piece of the body"), and the destruction of the spinal cord leads to their disappearance.

It was revealed that stimuli can be not only external, but also internal, the role of the posterior (sensory) and anterior (motor) roots of the spinal cord (Bell-Magendie law) was established. Very actively segmental reflexes were studied by C. Sherrington ( late 18th in. - early XIX in.).

Third stage- the victory of materialistic ideas about mental activity (I.M. Sechenov, 60s of the 19th century). Watching the development of children, I.M. Sechenov came to the conclusion that the principle of reflex underlies the formation of mental activity. He expressed this position next sentence: "All acts of conscious and unconscious life are, by way of origin, reflexes." Thus, I.M. Sechenov took the path of determinism in matters of human mental activity. IM Sechenov raised the question of the existence of two kinds of reflexes. First, permanent, congenital carried out by the lower parts of the nervous system. He called them: "pure" reflexes. Secondly, the reflexes of the brain are changeable, acquired in individual life. I. M. Sechenov imagined these reflexes simultaneously both physiological and psychic. Thus, the inseparability of mental processes from the brain and, at the same time, the conditionality of the psyche by the external world was shown for the first time..

In the study of reflexes, I. M. Sechenov also substantiated the adaptive nature of the variability of the reflex, discovered inhibition of reflexes (1863, central inhibition), summation, and excitation in the central nervous system (1868).

Fourth stage- the foundations of the doctrine of higher nervous activity were developed (IP Pavlov, early 20th century). I.P. Pavlov experimentally confirmed the possibility of the formation of conditioned reflexes and used them as objective method the study of mental activity (higher nervous activity, according to IP Pavlov).

As a result, ideas about the reflex mechanisms of the activity of the nervous system were formed into a single reflex theory. reflex theory - a theory of behavior that considers it as an activity of the body that occurs in response to the emergence of stimuli from the external world or the internal environment.

According to I.P. Pavlov's reflex theory is based on three main principles:

· principle of determinism (causality)- according to which a reflex reaction occurs only in response to an irritating stimulus. The principle of determinism establishes complete conditionality material reasons all phenomena in the body, including higher nervous activity. The study of the functions of the cerebral cortex allowed Pavlov to know the laws governing conditioned reflex activity so accurately that it became possible to largely control this activity in animals (dogs) and predict in advance what changes would occur under certain conditions.

· structural principle- establishes that all nervous processes are the result of the activity of certain structural formations - nerve cells, and depend on the properties of these cells. However, if before Pavlovian properties various cells and cell groups of the central nervous system were considered constant, Ivan Petrovich showed in his theory of conditioned reflexes that the properties of these cells change in the process of development. The localization of functions in the cerebral cortex should not, therefore, be interpreted only as a spatial distribution of cells with different properties. In addition, it provides that a reflex reaction is possible only if all components of the reflex arc are in an anatomically and physiologically intact state. In this formulation, it is known as the integrity principle.

· finally principle of analysis and synthesis establishes that each response is always adequate to the qualities and nature of the acting stimulus. According to this principle, in the process of reflex activity, on the one hand, fragmentation surrounding nature on a huge mass of separately perceived phenomena, and on the other hand, the transformation of simultaneously or sequentially acting stimuli ( different nature) into complex ones. A rough analysis can already be carried out by the lower parts of the nervous system, since stimulation of different receptors, each group of which perceives certain environmental influences, causes only certain unconditioned reflexes. However higher analysis, thanks to which the existence of an animal organism in a constantly changing environment is possible, is carried out by the cerebral cortex and is based on the ability to form conditioned reflexes, as well as on the ability to differentiate stimuli.

Fifth stage- the doctrine of functional systems was created (P.K. Anokhin, mid-20th century)

The reflex, according to Anokhin, is a closed ring or spiral, consisting of a number of successive processes:

1) processes nervous excitement resulting from external or internal stimulation of the senses ( initial link);

2) processes of afferent synthesis, carried out by analyzing the incoming information to the brain and making a decision in connection with this ( central link);

3) the body's response to the command of the brain (motor link);

4) feedback on the results of the actions performed (final link). Feedback in this case, it creates the possibility of assessing the compliance or non-compliance of the results obtained with the programmed actions. The exclusion of back afferent signals leads to an incorrect response of the body to incoming external or internal stimuli.