Peculiarities without conditioned reflexes

In the specialized literature, in the conversations of specialists - cynologists and amateur trainers, the term "reflex" is often used, but at the same time there is no common understanding of the meaning of this term among cynologists. Now many are addicted to Western training systems, new terms are being introduced, but few people fully understand the old terminology. We will try to help systematize the ideas about reflexes for those who have already forgotten a lot, and to get these ideas for those who are just starting to master the theory and methodology of training.

A reflex is the body's response to a stimulus.

(If you haven't read the article on irritants, be sure to read it first and then skip to this material). Unconditioned reflexes are divided into simple (food, defensive, sexual, visceral, tendon) and complex reflexes (instincts, emotions). Some researchers to B. r. include indicative (orientation-research) reflexes. The instinctive activity of animals (instincts) includes several stages of animal behavior, and individual stages its executions are sequentially connected with each other by the type of a chain reflex. The question of the mechanisms of closure B. r. insufficiently studied. According to the teachings of I.P. Pavlova about the cortical representation of B. p., each unconditional irritation, along with the inclusion of subcortical structures, causes excitation of nerve cells in the cortex hemispheres brain. Studies of cortical processes using electrophysiological methods have shown that the unconditioned stimulus arrives in the cerebral cortex in the form of a generalized flow of ascending excitations. Based on the position of I.P. Pavlov about the nerve center as a morphological and functional set of nerve formations located in various departments of the central nervous system, the concept of the structural and functional architecture of B. r. The central part of the B.'s arc. does not pass through any one part of the central nervous system, but is multi-storey and multi-branched. Each branch passes through some important part of the nervous system: the spinal cord, medulla oblongata, midbrain, cerebral cortex. The higher branch, in the form of a cortical representation of one or another B. r., serves as the basis for the formation of conditioned reflexes. Evolutionarily more primitive animal species are characterized by simple B. r. and instincts, for example, in animals, in which the role of acquired, individually developed reactions is still relatively small and innate, albeit complex forms of behavior predominate, tendon and labyrinth reflexes dominate. With complication structural organization senior researcher and the progressive development of the cerebral cortex, complex unconditioned reflexes and, in particular, emotions acquire a significant role. B.'s studying r. is important for the clinic. So, in conditions of pathology, c.n.s. B. r. characteristic of the early stages of onto- and phylogenesis (sucking, grasping, reflexes of Babinsky, Bekhterev, etc.) may appear, which can be considered as rudimentary functions, i.e. functions that existed earlier, but suppressed in the process of phylogenesis by the higher divisions of the c.s.s. When the pyramidal tracts are damaged, these functions are restored due to the resulting separation between the phylogenetically ancient and later developed sections of the c.n.s.

Unconditioned reflexes

An unconditioned reflex is an innate response of the body to a stimulus. Each unconditioned reflex appears at a certain age and in response to certain stimuli. The puppy in the very first hours after its birth is able to find the mother's nipples and suck milk. These actions are provided by innate unconditioned reflexes. Later, a reaction to light and moving objects begins to appear, the ability to chew and swallow solid food. At a later age, the puppy begins to actively explore the territory, play with littermates, show an orienting reaction, an active-defensive reaction, a reaction of pursuit and prey. All these actions are based on innate reflexes, varying in complexity and manifested in different situations.

According to the level of complexity, unconditioned reflexes are divided into:

simple unconditioned reflexes

reflex acts

Behavior reactions

instincts

Simple unconditioned reflexes are elementary innate reactions to stimuli. For example, withdrawal of a limb from a hot object, blinking of the eyelid when a mote enters the eye, etc. Simple unconditioned reflexes to the corresponding stimulus always appear, they are not amenable to change and correction.

Reflex acts- actions determined by several simple unconditioned reflexes, always performed in the same way and independently of the dog's consciousness. Basically, reflex acts ensure the vital activity of the organism, therefore they always manifest themselves reliably and cannot be corrected.

Some examples of reflex acts:

Breath;

swallowing;

regurgitation

When training and raising a dog, it should be remembered that the only way to prevent the manifestation of one or another reflex act - to change or remove the stimulus that causes it. So, if you want your pet not to send natural needs while practicing obedience skills (and he will do it anyway, if necessary, despite your prohibition, because this is a manifestation of a reflex act), then walk the dog before training. Thus, you will eliminate the corresponding stimuli that cause a reflex act that is undesirable for you.

Behavioral reactions - the dog's desire to carry out certain actions, based on a complex of reflex acts and simple unconditioned reflexes.

For example, the reaction of fetching (the desire to pick up and wear objects, play with them); active-defensive reaction (the desire to show an aggressive reaction to a person); olfactory-search reaction (the desire to search for objects by their smell) and many others. Note that the reaction of a behavior is not the behavior itself. For example, a dog has a strong innate active-defensive reaction of behavior and at the same time is physically weak, small in stature, and also in the process of life constantly received a negative result when trying to implement aggression on a person. Will she act aggressively and will she be dangerous in a particular situation? Probably not. But the innate aggressive tendency of the animal must be taken into account, and this dog will be able to attack a weak opponent, for example, a child.

Thus, behavioral responses are the cause of many dog ​​actions, but in a real setting, their manifestation can be controlled. We have given a negative example showing undesirable dog behavior. But attempts to develop the desired behavior in the absence of the necessary reactions will end in failure. For example, it is useless to prepare a search dog from a candidate who lacks an olfactory-search reaction. You will not get a guard from a dog with a passive-defensive reaction (from a cowardly dog).

Instincts are an innate motivation that determines long-term behavior aimed at satisfying certain needs.

Examples of instincts: sexual instinct; the instinct of self-preservation; hunting instinct (often transformed into prey instinct), etc. The animal does not always perform actions dictated by instinct. A dog may, under the influence of certain stimuli, exhibit behavior that is in no way connected with the realization of one or another instinct, but in general the animal will strive to realize it. For example, if a female in heat appears near the training ground, the behavior of the male will be determined by sexual instinct. By controlling the dog, applying certain stimuli, you can make the dog work, but if your control weakens, the dog will again seek to realize sexual motivation. Thus, unconditioned reflexes are the main motivating force that determines the behavior of the animal. The lower the level of organization of unconditioned reflexes, the less they are controlled. Unconditioned reflexes are the basis of dog behavior, so careful selection of an animal for training, determination of abilities for a particular service (work) is extremely important. It is believed that the success of the effective use of the dog is determined by three factors:

Selection of a dog for training;

Training;

Proper use of the dog

Moreover, the importance of the first item is estimated at 40%, the second and third - 30% each.

Animal behavior is based on simple and complex innate reactions - the so-called unconditioned reflexes. An unconditioned reflex is an innate reflex that is persistently inherited. An animal for the manifestation of unconditioned reflexes does not need training, it is born with reflex mechanisms ready for their manifestation. For the manifestation of an unconditioned reflex, you need:

Firstly, the irritant that causes it,

Secondly, the presence of a certain conductor apparatus, i.e., a ready-made nerve path (reflex arc), which ensures the passage of nerve irritation from the receptor to the corresponding working organ (muscle or gland).

If a dog is poured hydrochloric acid of a weak concentration (0.5%) into his mouth, he will try to throw acid out of his mouth with vigorous movements of his tongue, and at the same time liquid saliva will flow, protecting the oral mucosa from acid damage. If you apply pain irritation to the limb of the dog, it will certainly pull back, tighten its paw. These reactions of the dog to the irritating effect of hydrochloric acid or to painful irritation will manifest themselves with a strict regularity in any animal. They certainly manifest themselves under the action of the corresponding stimulus, which is why they were named by I.P. Pavlov unconditioned reflexes. Unconditioned reflexes are caused by both external stimuli and stimuli coming from the body itself. All acts of activity of a newborn animal are unconditioned reflexes that ensure the existence of the organism for the first time. Breathing, sucking, urination, feces, etc. - all these are innate unconditional reflex reactions; moreover, the irritations that cause them come mainly from internal organs(crowded bladder causes urination, the presence of feces in the rectum causes attempts leading to fecal eruption, etc.). However, as the dog grows and matures, a number of other, more complex unconditioned reflexes appear. Such unconditioned reflexes include, for example, the sexual reflex. The presence of a female near a male to a state of estrus (in a pustovka) causes an unconditional reflex sexual reaction on the part of the male, which manifests itself in the form of a sum of rather complex, but at the same time natural actions aimed at sexual intercourse. The dog does not learn this reflex reaction, it naturally begins to manifest itself in the animal during puberty, in response to a certain (albeit complex) stimulus (bitch and estrus) and therefore should also be attributed to the group of unconditioned reflexes. The whole difference between, for example, the sexual reflex and withdrawal of the paw in response to painful stimulation lies only in the varying complexity of these reflexes, but in principle they do not differ from each other. Therefore, unconditioned reflexes can be divided according to the principle of their complexity into simple and complex. However, it must be borne in mind that in the manifestation of a complex unconditioned reflex, whole line simple unconditioned reflex acts. So, for example, the food unconditioned reflex reaction of even a newly born puppy is carried out with the participation of a number of simpler unconditioned reflexes - acts of sucking, swallowing movements, reflex activity of the salivary glands and glands of the stomach. At the same time, one unconditioned reflex act is a stimulus for the manifestation of the next, i.e. it is as if a chain of reflexes is completed, therefore they speak of the chain nature of unconditioned reflexes. Academician I.P. Pavlov drew attention to some of the basic unconditioned reflexes of animals, pointing out at the same time that this question had not yet been sufficiently developed.

Firstly, animals have an unconditioned food reflex aimed at providing the body with food,

Secondly, the unconditioned sexual reflex, aimed at the reproduction of offspring, and the parental (or maternal) reflex, aimed at preserving the offspring,

Thirdly, defensive reflexes associated with the protection of the body.

Moreover, defensive reflexes are of two kinds

an active (aggressive) defensive reflex underlying the viciousness, and

passive defensive reflex underlying cowardice.

These two reflexes are diametrically opposed in the form of their manifestation; one is aimed at an attack, the other, on the contrary, at escaping from the irritant that causes it.

Sometimes in dogs, active and passive defensive reflexes appear simultaneously: the dog barks, rushes, but at the same time tucks its tail, rushes about, and runs away at the slightest active action from a stimulus (for example, a person).

Finally, animals have a reflex associated with the animal's constant familiarization with everything new, the so-called orienting reflex, which ensures that the animal is aware of all the changes taking place around it, and which underlies the constant "reconnaissance" in its environment. In addition to these basic complex unconditioned reflexes, there are a number of simple unconditioned reflexes associated with breathing, urination, feces and other functional functions of the body. Finally, each animal species has a number of its own, unique to it, complex unconditioned reflex acts of behavior (for example, the complex unconditioned reflexes of beavers associated with the construction of dams, houses, etc.; unconditioned bird reflexes associated with the construction of nests, spring and autumn flights, etc.). Dogs also have a number of special unconditioned reflex acts of behavior. Thus, for example, hunting behavior is based on a complex unconditioned reflex associated in the wild ancestors of the dog with the food unconditioned reflex, which turned out to be so modified and specialized in hunting dogs that it acts as an independent unconditioned reflex. Moreover, different breeds dogs this reflex has a different expression. In gun dogs, the irritant is mainly the smell of a bird, and quite specific birds; chicken (grouse, black grouse), waders (snipe, woodcock, great snipe), shepherds (corncrake, swamp chicken, etc.). Beagle dogs have the look or smell of a hare, fox, wolf, etc. Moreover, the very form of unconditioned reflex acts of behavior in these dogs is completely different. The gun dog, having found a bird, makes a stand over it; the hound dog, having got on the trail, drives the beast along it with barking. Service dogs often have a pronounced hunting reflex aimed at pursuing the animal. The question of the possibility of changing unconditioned reflexes under the influence of the environment is extremely important. A demonstrative experiment in this direction was carried out in the laboratory of Academician I.P. Pavlova.

Two litters of puppies were divided into two groups and brought up in sharply different conditions. One group was brought up in freedom, the other - in isolation from the outside world (indoors). When the puppies grew up, it turned out that they differ sharply from each other in behavior. Those who were raised in freedom did not have a passive defensive reaction, while those who lived in isolation had it in a pronounced form. Academician I. P. Pavlov explains this by the fact that all puppies at a certain age of their development show a reflex of primary natural caution to all new stimuli for them. As you get to know environment they have a gradual inhibition of this reflex and switching it into an orienting reaction. The same puppies, which during the period of their development did not have the opportunity to get acquainted with all the diversity of the outside world, do not get rid of this puppyish passive-defensive reflex and remain cowardly for the rest of their lives. The manifestation of an active-defensive reaction was studied on dogs raised in kennels, i.e. in conditions of partial isolation, and among amateurs, where puppies have the opportunity to more contact with the diversity of the outside world. The extensive material collected on this subject (Krushinsky) showed that dogs reared in kennels have a less pronounced active defensive reaction than dogs reared by individuals. Growing puppies in kennels where unauthorized access is restricted have fewer opportunities to develop an actively defensive reaction than puppies raised by amateurs. Hence the difference in the active-defensive reaction that is observed in dogs, both of these groups, brought up in different conditions. The examples cited confirm the enormous dependence of the formation of passive- and active-defensive reactions on the conditions for raising a puppy, as well as the variability of complex unconditional reflex behavior under the influence of the external conditions in which the dog lives and is brought up. These examples indicate the need for careful attention to the conditions for raising puppies. Isolated or partially isolated conditions for raising puppies contribute to the formation of a dog with a passive-defensive reaction, which is unsuitable for some types of dog service. Creation right conditions raising puppies, which would provide them with a constant acquaintance with all the diversity of the outside world and give the puppy the opportunity to show its active-defensive reaction (the first manifestations of which begin as early as one and a half to two months), helps to raise a dog with a developed active-defensive reaction and the absence of a passive- defensive. However, it must be borne in mind that in individual dogs brought up in the same conditions, there is a difference in the manifestation of defensive reactions, which depends on congenital individual features characteristic of the parents. Therefore, improving the conditions for raising puppies, it is necessary to Special attention and selection of parents. Of course, it is impossible to use animals with a passive-defensive reaction as producers for obtaining service dogs. We examined the role of the dog's individual experience in the formation of complex unconditioned reflex defensive behavior. However, the formation of other unconditioned reflexes in response to certain stimuli is closely dependent on the individual experience of the dog. Take for example the food unconditioned reflex. It should seem obvious to everyone that a dog's food reaction to meat is an unconditioned reflex. However, experiments conducted by one of the students of Academician I.P. Pavlov showed that this was not so. It turned out that dogs raised on a diet devoid of meat, when given a piece of meat for the first time, did not react to it as an edible substance. However, as soon as such a dog put a piece of meat in its mouth once or twice, it swallowed it and after that already reacted to it as to a food substance. Thus, the manifestation of the alimentary reflex even to such a seemingly natural stimulus as meat requires a very short, but still individual experience.

Thus, the above examples show that the manifestation of complex unconditioned reflexes depends on the previous life.

Let us now dwell on the concept of instinct.

Under the instinct understand the complex actions of the animal, leading without prior training to the best adaptation of it to certain environmental conditions. A duckling that first encounters water will swim in exactly the same way as an adult duck; the chick of the swift, which flew out of the nest for the first time, has perfect flight techniques; young migratory birds fly south in autumn, all examples of so-called instinctive actions, which ensure the adaptation of the animal to certain and constant conditions of its life. Academician IP Pavlov, comparing instincts with complex unconditioned reflexes, pointed out that there is no difference between them. He wrote: “both reflexes and instincts are natural reactions of the organism to certain agents, and therefore there is no need to designate them different words. The word reflex has the advantage, because it has been given a strictly scientific meaning from the very beginning. Can these innate, unconditioned reflex acts of animal behavior fully ensure its existence. This question has to be answered in the negative. Despite the fact that unconditioned reflexes are capable of ensuring a normal existence in a newly born animal, they are completely insufficient for the normal existence of a growing or adult animal. This is clearly proved by the experiment with the removal of the hemispheres of the dog's brain, that is, the organ that is associated with the possibility of acquiring individual experience. A dog with remote hemispheres of the brain eats and drinks if food and water are brought to its mouth, shows a defensive reaction to painful irritation, urinates and stools. But at the same time, such a dog is a profoundly disabled person, completely incapable of independent existence and adaptation to living conditions, because such adaptation is achieved only with the help of individually acquired reflexes, the emergence of which is associated with the cortex of the cerebral hemispheres. Unconditioned reflexes are thus the base, the foundation on which all animal behavior is built. But they alone are still insufficient for the adaptation of the higher vertebrate animal to the conditions of existence. The latter is achieved with the help of the so-called conditioned reflexes, which are formed during the life of an animal on the basis of its unconditioned reflexes.

Topic 22. Characteristics and properties of conditioned reflexes

One of the main elementary acts of higher nervous activity is a conditioned reflex.

The concept of conditioned reflex activity is inextricably linked with the name of Ivan Petrovich Pavlov, who at the beginning of the last century discovered and studied the mechanisms of the formation of a conditioned reflex. Today, in any textbook of physiology published in any country in the world, such reflexes are called classical or Pavlovian. studying digestive system dogs, Pavlov discovered that animals begin to salivate long before they receive food at the mere sight of a white-coated attendant who usually brings it. As Pavlov continued his experiments, he discovered that the sound of a bell or a flash of light preceding the appearance of food can also cause dogs to salivate. Thus, the development of a conditioned reflex occurs when the stimulus that causes vivo a certain reaction (for example, food), is combined several times with some other, previously neutral stimulus (for example, a call). After that, a neutral stimulus begins to evoke the same response. I. P. Pavlov showed that while in the underlying parts of the central nervous system - the subcortical nuclei, the brain stem, the spinal cord - reflex reactions are carried out along innate, hereditarily fixed nerve pathways, in the cerebral cortex, nerve connections are developed and created in the process individual life of animals and humans, as a result of a combination of countless stimuli acting on the body.

The discovery of this fact made it possible to divide the entire set of reflex reactions occurring in the body into two main groups: unconditioned and conditioned reflexes.

Differences between conditioned and unconditioned reflexes:

Unconditioned reflexes	Conditioned reflexes
these are congenital, hereditary reactions of the body	these are reactions acquired by the body in the process of individual development on the basis of "life experience"
are specific, i.e. characteristic of all representatives of a given species	are individual: some representatives of the same species may have them, while others may not
relatively constant, usually persisting throughout life	are unstable and, depending on certain conditions, they can develop, gain a foothold or disappear
carried out in response to adequate stimuli applied to one specific receptive field	can form in response to a wide variety of stimuli applied to various receptive fields
are closed mainly at the level of the spinal cord and the brain stem	closed at the level of the cortex. After removal of the cerebral cortex, the developed conditioned reflexes disappear
are carried out through a phylogenetically fixed, anatomically expressed reflex arc.	carried out through functional temporary connections

It should be noted, however, that in humans and monkeys, which have a high degree of corticalization of functions, many complex unconditioned reflexes are carried out with the obligatory participation of the cerebral cortex. This is proved by the fact that its lesions in primates lead to pathological disturbances of unconditioned reflexes and the disappearance of some of them.

It should also be emphasized that not all unconditioned reflexes appear immediately at the time of birth. Many unconditioned reflexes, for example, those associated with locomotion, sexual intercourse, occur in humans and animals a long time after birth, but they necessarily appear under the condition of normal development of the nervous system.

Conditioned reflexes are developed on the basis of unconditioned reflexes. The essence of the conditioned reflex activity of the body is reduced to the transformation of an indifferent stimulus into a signal, meaning, due to the repeated reinforcement of irritation with an unconditioned stimulus.. Due to the reinforcement of the conditioned stimulus by the unconditioned previously indifferent stimulus, in the life of the organism it is associated with biologically important event and thereby signals the onset of this event. In this case, any innervated organ can act as an effector link of the reflex arc of the conditioned reflex. There is no organ in the human and animal organism, the work of which could not change under the influence of a conditioned reflex. Any function of the organism as a whole or its individual physiological systems can be modified (enhanced or suppressed) as a result of the formation of the corresponding conditioned reflex.

General rules the formation of conditioned reflexes are reduced to the following.

1) The indifferent stimulus should appear a little earlier than the unconditioned one. If you turn on the bell or light bulb after feeding, the reflex will not develop. If an indifferent stimulus is used half an hour before feeding, and not a few seconds before it, then nothing will work either.

2) The indifferent stimulus must be weaker than the unconditioned one.. A powerful searchlight instead of a light bulb or a fire siren instead of a bell can only frighten the animal, while a light bulb or a bell at first causes an orienting reflex (“what is it?”), which usually disappears soon due to the habituation reaction. After that, the stimulus becomes indifferent or indifferent. The strength of the unconditioned stimulus can be determined, for example, by the feeling of hunger, and therefore, with a full stomach, digestive conditioned reflexes are poorly formed.

3) Must, so that other stimuli do not interfere with the development of conditioned reflexes. It is no coincidence that by order of Pavlov, special “towers of silence” were built at his institute for experiments, since external stimuli (for example, noise or the arrival of an outsider) can interfere with the manifestation of already developed reflexes and slow down the formation of new ones.

To develop a conditioned reflex the normal physiological state of the cortical and subcortical structures is also necessary, forming the central representation of the corresponding conditioned and unconditional stimuli, the absence of significant pathological processes in the body.

If these conditions are met, a conditioned reflex can be developed for almost any stimulus. Conditioned reflexes can be developed not only with positive, but also with negative views reinforcements, for example, in case of pain. So, if you turn on the bell shortly before the painful irritation of the dog's paw electric shock, she will soon begin to bend this paw at the mere inclusion of a bell, which becomes a conditioned stimulus. People also form similar conditioned reflex connections. In this way, in particular, certain emotional reactions, especially fear, can be developed. The child, while he is not yet grown enough to understand why doctors and nurses prick him with needles and in general torture him in every possible way against his will, often begins to cry at the sight of a man in a white coat. He learned to associate cold instruments, unpleasant odors, hypodermic injections with white coats, and he developed a conditioned response - fear - to a previously neutral stimulus (white coat).

The physiological mechanism underlying the conditioned reflex. In the zone of cortical representation of the conditioned stimulus and cortical (or subcortical) representation of the unconditioned stimulus, two foci of excitation are formed. The focus of excitation, caused by an unconditioned stimulus of the external or internal environment of the body, as a stronger (dominant) one, attracts excitation from the focus of a weaker excitation caused by a conditioned stimulus. After several repeated presentations of the conditioned and unconditioned stimuli between these two zones, a stable path of movement of excitation is "blazed": from the focus caused by the conditioned stimulus to the focus caused by the unconditioned stimulus. As a result, the isolated presentation of only the conditioned stimulus now leads to the response evoked by the previously unconditioned stimulus.

Intercalary and associative neurons of the cerebral cortex act as the main cellular elements of the central mechanism for the formation of a conditioned reflex.

IP Pavlov initially assumed that the conditioned reflex is formed at the level of the cortex - subcortical formations (a temporary connection is closed between the cortical neurons in the zone of representation of the indifferent conditioned stimulus and the subcortical nerve cells that make up the central representation of the unconditioned stimulus). In later works, I. P. Pavlov explained the formation of a conditioned reflex connection by the formation of a connection at the level of the cortical zones of the representation of conditioned and unconditioned stimuli. The data of modern neurophysiology indicate the possibility different levels closure, formation of a conditioned reflex connection (cortex - cortex, cortex - subcortical formations, subcortical formations - subcortical formations) with a dominant role in this process of cortical structures. Obviously, the physiological mechanism for the formation of a conditioned reflex is a complex dynamic organization of cortical and subcortical structures.

The biological significance of conditioned reflexes is that they make it possible to much better and more accurately adapt to the conditions of existence and survive in these conditions. As a result of the formation of conditioned reflexes, the body reacts not only directly to unconditioned stimuli, but also to the possibility of their action on it; reactions appear some time before unconditional irritation. This very organism turns out to be prepared in advance for the actions that it has to carry out in a given situation. Conditioned reflexes help to find food, avoid danger in advance, eliminate harmful influences, etc. The adaptive significance of conditioned reflexes is also manifested in the fact that the precedence of a conditioned stimulus to an unconditioned one strengthens the unconditioned reflex and accelerates its development.

Orthodox followers of Pavlov after his death tried almost any form mental activity fit under the theory of conditioned reflexes. So, for example, if a conditioned salivary reflex to a bell is formed, then the bell can be used as a reinforcement after, for example, turning on a light bulb and this will ensure that just turning on the light bulb will also cause salivation. Reflexes of this type, where a previously formed temporary connection is used as a reinforcement, are called conditioned reflexes. reflexes of the second order. It is not difficult to imagine education on the same principle of reflexes of the third, fourth, etc. orders. A person can form, for example, a reflex of the 12th order or more. However, from all this kind of evidence, it still does not come out that the creation of the theory of relativity or the Mona Lisa is just the result of conditioned reflex activity. Conditioned reflexes of the second and more complex order are more difficult to form and differ less strength. Conditioned reflexes of the second and higher order include conditioned reflexes developed to a verbal signal (the word here represents a signal to which a conditioned reflex was previously formed when reinforced with an unconditioned stimulus).

Inhibition of conditioned reflexes. Unlike unconditioned, conditioned reflexes are easily amenable to inhibition.

depending on the nature physiological mechanism, underlying the inhibitory effect on the conditioned reflex activity of the body, distinguish unconditional(external and beyond) and conditional(internal) braking conditioned reflexes.

External braking conditioned reflex occurs under the influence of extraneous stimuli that cause a new reflex reaction. This inhibition is called external because it develops as a result of processes occurring in areas of the cortex that are not involved in the implementation of this conditioned reflex. External inhibition occurs at the first presentation of the corresponding signal. So, if before the beginning of the conditioned food reflex, an extraneous sound suddenly appears or some extraneous smell appears, or the lighting changes sharply, then the conditioned reflex decreases or even completely disappears. This is explained by the fact that every new stimulus causes an orienting reflex, which inhibits the conditioned reaction.

Extreme braking conditioned reflex develops either with excessive great strength stimulus, or at a low functional state of the central nervous system, at the level of which ordinary threshold stimuli acquire the character of excessive, strong ones. Outrageous braking has a protective value.

The biological meaning of unconditional external inhibition of conditioned reflexes is to provide a reaction to the most important for the body in this moment time, a stimulus with simultaneous suppression, suppression of the reaction to a secondary stimulus, which in this case is a conditioned stimulus.

Conditional inhibition conditioned reflex requires special development. Since the development of the inhibitory effect is associated with the neurophysiological mechanism of the formation of a conditioned reflex, such inhibition belongs to the category of internal inhibition, and the manifestation of this type of inhibition is associated with certain conditions (for example, repeated use of a conditioned stimulus without reinforcement), such inhibition is also conditional.

The biological meaning of the internal inhibition of conditioned reflexes is that the changed conditions of the external environment (the cessation of reinforcement of the conditioned stimulus by the unconditioned one) requires a corresponding adaptive adaptive change in conditioned reflex behavior. The conditioned reflex is oppressed, suppressed, because it ceases to be a signal foreshadowing the appearance of an unconditioned stimulus.

There are four types of internal inhibition: extinction, differentiation, conditional inhibition, delay.

If a conditioned stimulus is presented without reinforcement by an unconditioned stimulus, then some time after the isolated application of the conditioned stimulus, the reaction to it fades away. This inhibition of the conditioned reflex is called fading(fading). The extinction of the conditioned reflex- this is a temporary inhibition, inhibition of the reflex reaction. It does not mean the destruction, the disappearance of this reflex reaction. After some time, a new presentation of a conditioned stimulus without reinforcing it with an unconditioned stimulus at first again leads to the manifestation of a conditioned reflex reaction.

If a dog develops a food salivary-excretory conditioned reflex to metronome beats with a frequency of 60 times per minute, then the animal will first respond with saliva to metronome beats of any frequency. If you give the animal two stimuli - metronome beats with a frequency of 60 and 100 times per minute and the first of them, as before, is reinforced with food, and the second is not, then gradually the secretion of saliva at a frequency of 100 beats will stop and will remain only for 60. This type of internal ( conditional) inhibition is called differential inhibition(differentiation). Differential inhibition underlies many forms of learning related to the development of fine skills.

If the conditioned stimulus to which the conditioned reflex is formed is applied in combination with some other stimulus and their combination is not reinforced by an unconditioned stimulus, inhibition of the conditioned reflex evoked by this stimulus occurs. This type of conditional inhibition is called conditional brake.

delayed braking occurs when the reinforcement of the conditioned signal with an unconditioned stimulus is carried out with a great delay (2-3 minutes) in relation to the moment of presentation of the conditioned stimulus.

Such habitual actions as breathing, swallowing, sneezing, blinking - occur without the control of consciousness, are innate mechanisms that help a person or animal survive and ensure the preservation of the species - all these are unconditioned reflexes.

What is an unconditioned reflex?

I.P. Pavlov, a physiologist, devoted his life to the study of higher nervous activity. In order to understand what unconditioned human reflexes are, it is important to consider the meaning of the reflex as a whole. Any organism that has a nervous system carries out reflex activity. Reflex - a complex reaction of the body to internal and external stimuli, carried out in the form of a reflex response.

Unconditioned reflexes are innate stereotypical reactions laid down at the genetic level in response to changes in internal homeostasis or environmental conditions. For the emergence of unconditioned reflexes, special conditions are automatic reactions that can fail only in severe illnesses. Examples of unconditioned reflexes:

• withdrawal of limb from contact with hot;
• knee jerk;
• sucking, grasping in newborns;
• swallowing;
• salivation;
• sneezing
• blinking.

What is the role of unconditioned reflexes in human life?

Human evolution over the centuries has been accompanied by a change in the genetic apparatus, the selection of traits that are necessary for survival in nature. became highly organized matter. What is the importance of unconditioned reflexes - the answers can be found in the works of physiologists Sechenov, I.P. Pavlova, P.V. Simonov. Scientists have identified several important functions:

• maintaining homeostasis (self-regulation of the internal environment) in optimal balance;
• adaptation and adaptation of the body (mechanisms of thermoregulation, respiration, digestion);
• preservation of species characteristics;
• reproduction.

Signs of unconditioned reflexes

The main feature of unconditioned reflexes is innateness. Nature has made sure that all functions important for life in this world are reliably recorded on the nucleotide chain of DNA. Other characteristic features:

• prior learning and mind control are not required;
• are specific;
• strictly specific - occur when in contact with a specific stimulus;
• permanent reflex arcs in the lower parts of the central nervous system;
• most unconditioned reflexes persist throughout life;
• a set of unconditioned reflexes helps the body in the early stages of development to adapt to the environment;
• are the basic basis for the emergence of conditioned reflexes.

Types of unconditioned reflexes

Unconditioned reflexes have different kind classification, I.P. Pavlov first divided them into: simple, complex and complex. In the distribution of unconditioned reflexes by the factor of certain space-time regions occupied by each creature, P.V. Simonov divided the types of unconditioned reflexes into 3 classes:

1. Role unconditioned reflexes- appear in interaction with other intraspecific representatives. These are reflexes: sexual, territorial behavior, parental (maternal, paternal), phenomenon.
2. Unconditioned vital reflexes- all the basic needs of the body, the deprivation or dissatisfaction of which leads to death. Provide individual safety: drinking, food, sleep and wakefulness, indicative, defensive.
3. Unconditioned reflexes of self-development- are included in the development of a new, previously unfamiliar (knowledge, space):

• reflex of overcoming or resistance (freedom);
• game;
• imitative.

Types of inhibition of unconditioned reflexes

Excitation and inhibition are important innate functions of higher nervous activity that ensure the coordinated activity of the organism and without which this activity would be chaotic. Inhibitory unconditioned reflexes in the process of evolution turned into a complex response of the nervous system - inhibition. I.P. Pavlov distinguished 3 types of inhibition:

1. Unconditional braking (external)- the reaction "What is it?" allows you to assess whether the situation is dangerous or not. In the future, with the frequent manifestation of an external stimulus that does not carry danger, inhibition does not occur.
2. Conditional (internal) braking- the functions of conditioned inhibition ensure the extinction of reflexes that have lost their value, help to distinguish signals that are useful with reinforcement from useless ones, and form a delayed reaction to a stimulus.
3. Outrageous (protective) braking- an unconditional safety mechanism provided by nature, triggered by excessive fatigue, excitement, severe injuries(fainting, coma).

CHAPTER 5

5.1. Characteristics of unconditioned and conditioned reflexes

The hypothesis of the reflex nature of brain activity was first expressed by I. M. Sechenov in his famous work"Reflexes of the Brain" (1862). According to this theory: “All acts of conscious and unconscious life are by their mode of origin reflexes, mental activity -is a reflex or reflective activity. The provisions of the reflex theory, formulated by I. M. Sechenov, were further developed by I. P. Pavlov, N. E. Vvedensky, A. A. Ukhtomsky, V. M. Bekhterev, P. K. Anokhin.

I. P. Pavlov divided the entire set of reflexes occurring in the body into two groups: unconditional and conditional reflexes.

Unconditioned reflexes are congenital, hereditarily fixed, the same in all animals of a given species. They are relatively constant throughout life and are carried out with the participation of all departments of the central nervous system. Unconditioned reflexes arise in response to stimulation of certain receptors and serve to maintain the normal functioning of the body and its relationship with the environment.

Unconditioned reflexes can be simple or complex. simple reflexes are expressed in a single reflex act, for example, pulling back the hand during pain stimulation. Compound reflexes are a series of successive reactions, where the end of one reaction causes another to begin. Such complex reflex acts are instincts that ensure the behavior of humans and animals under changing environmental conditions.

Conditioned reflex this is the body's response to any impact, with the participation of the cortex. Conditioned reflexes are individual reactions acquired during life. They are formed with the obligatory participation of the cerebral cortex. Conditioned reflexes are developed by combining stimulation of any receptors with some kind of unconditional reflex activity. Conditioned reflexes arise and are fixed during reinforcement or disappear if reinforcement is absent and the need for them disappears. The mechanism of formation of a conditioned reflex lies in the fact that a temporary connection is formed in the cerebral cortex between neurons excited by unconditioned and conditioned signals.

Conditioned reflexes expand the relationship of the organism with the external environment and provide expedient adaptation to changing conditions. In the conditioned reflex, I. P. Pavlov saw higher form reflex activity: a reaction not to a direct stimulus, but to a signal that precedes this irritation. Thus, the conditioned reflex can be considered as an early adaptive reaction, which is formed by the conditions of life. Under natural conditions, unconditioned reflexes, with which a child is born, in the course of life "acquire" various conditioned reflexes and in fact cease to exist in their pure form.

Reflex- the response of the body is not an external or internal irritation, carried out and controlled by the central nervous system. The development of ideas about human behavior, which has always been a mystery, was achieved in the works of Russian scientists I. P. Pavlov and I. M. Sechenov.

Reflexes unconditioned and conditional.

Unconditioned reflexes- these are innate reflexes that are inherited by offspring from parents and persist throughout a person's life. Arcs of unconditioned reflexes pass through the spinal cord or brain stem. The cerebral cortex does not participate in their formation. Unconditioned reflexes provide only those changes in the environment that many generations of a given species often encountered.

To include:

Food (salivation, sucking, swallowing);
Defensive (coughing, sneezing, blinking, pulling the hand away from a hot object);
Approximate ( skew eyes, turns);
Sexual (reflexes associated with reproduction and care of offspring).
The significance of unconditioned reflexes lies in the fact that thanks to them the integrity of the body is preserved, the maintenance of constancy and reproduction occurs. Already in a newborn child, the simplest unconditioned reflexes are observed.
The most important of these is the sucking reflex. The irritant of the sucking reflex is the touch of an object on the child's lips (mother's breasts, nipples, toys, fingers). The sucking reflex is an unconditioned food reflex. In addition, the newborn already has some protective unconditioned reflexes: blinking, which occurs if a foreign body approaches the eye or touches the cornea, constriction of the pupil when strong light is applied to the eyes.

Particularly pronounced unconditioned reflexes in various animals. Not only individual reflexes can be innate, but also more complex forms of behavior, which are called instincts.

Conditioned reflexes- these are reflexes that are easily acquired by the body during life and are formed on the basis of an unconditioned reflex under the action of a conditioned stimulus (light, knock, time, etc.). IP Pavlov studied the formation of conditioned reflexes in dogs and developed a method for obtaining them. To develop a conditioned reflex, an irritant is needed - a signal that triggers a conditioned reflex, repeated repetition of the action of the stimulus allows you to develop a conditioned reflex. During the formation of conditioned reflexes, a temporary connection arises between the centers and centers of the unconditioned reflex. Now this unconditioned reflex is not carried out under the influence of completely new external signals. These irritations from the outside world, to which we were indifferent, can now become of vital importance. During life, many conditioned reflexes are developed, which form the basis of our life experience. But this life experience makes sense only for this individual and is not inherited by its descendants.

into a separate category conditioned reflexes allocate motor conditioned reflexes developed during our life, i.e. skills or automated actions. The meaning of these conditioned reflexes is the development of new motor skills, the development of new forms of movements. During his life, a person masters many special motor skills associated with his profession. Skills are the basis of our behavior. Consciousness, thinking, attention are freed from performing those operations that have become automated and become skills. Everyday life. Most successful way mastery of skills is systematic exercises, correction of mistakes noticed in time, knowledge of the ultimate goal of each exercise.

If the conditioned stimulus is not reinforced for some time by the unconditioned stimulus, then the conditioned stimulus is inhibited. But it doesn't disappear completely. When the experiment is repeated, the reflex is very quickly restored. Inhibition is also observed under the influence of another stimulus of greater force.