Our nervous system is a complex mechanism for the interaction of neurons that send impulses to the brain, and it, in turn, controls all organs and ensures their work. This process of interaction is possible due to the presence in a person of the main inseparable acquired and innate forms of adaptation - conditional and unconditional reactions. A reflex is a conscious response of the body to certain conditions or stimuli. Such well-coordinated work of nerve endings helps us interact with the outside world. A person is born with a set of simple skills - this is called An example of such behavior: the ability of an infant to suck on its mother's breast, swallow food, blink.

and animal

As soon as a living being is born, he needs certain skills that will help ensure his life. The body actively adapts to the surrounding world, that is, it develops a whole range of purposeful motor skills. This mechanism is called species behavior. Each living organism has its own set of reactions and innate reflexes, which is inherited and does not change throughout life. But the behavior itself is distinguished by the method of its implementation and application in life: congenital and acquired forms.

Unconditioned reflexes

Scientists say that an innate form of behavior is an unconditioned reflex. An example of such manifestations has been observed since the birth of a person: sneezing, coughing, swallowing saliva, blinking. The transfer of such information is carried out by inheritance of the parent program by centers that are responsible for reactions to stimuli. These centers are located in the brain stem or spinal cord. Unconditioned reflexes help a person quickly and accurately respond to changes in the external environment and homeostasis. Such reactions have a clear demarcation depending on biological needs.

• Food.
• Approximate.
• Protective.
• Sexual.

Depending on the species, living beings have different reactions to the world around them, but all mammals, including humans, have a sucking skill. If you attach an infant or a young animal to the mother's nipple, a reaction will immediately occur in the brain and the feeding process will begin. This is the unconditioned reflex. Examples of eating behavior are inherited in all creatures that receive nutrients from mother's milk.

Defense reactions

These types of reactions to external stimuli are inherited and are called natural instincts. Evolution has laid in us the need to protect ourselves and take care of our safety in order to survive. Therefore, we have learned to instinctively respond to danger, this is an unconditioned reflex. Example: Have you noticed how the head deviates if someone raises a fist over it? When you touch a hot surface, your hand withdraws. This behavior is also called hardly a person in their right mind will try to jump from a height or eat unfamiliar berries in the forest. The brain immediately starts the process of processing information that will make it clear whether it is worth risking your life. And even if it seems to you that you don’t even think about it, the instinct immediately works.

Try to bring your finger to the baby's palm, and he will immediately try to grab it. Such reflexes have been developed over the centuries, however, now such a skill is not really needed by a child. Even among primitive people, the baby clung to the mother, and so she endured him. There are also unconscious innate reactions, which are explained by the connection of several groups of neurons. For example, if you hit the knee with a hammer, it will twitch - an example of a two-neuron reflex. In this case, two neurons come into contact and send a signal to the brain, causing it to respond to an external stimulus.

Delayed reactions

However, not all unconditioned reflexes appear immediately after birth. Some arise as needed. For example, a newborn baby practically does not know how to navigate in space, but after about a couple of weeks he begins to react to external stimuli - this is an unconditioned reflex. Example: the child begins to distinguish the voice of the mother, loud sounds, bright colors. All these factors attract his attention - an indicative skill begins to form. Involuntary attention is the starting point in the formation of the assessment of stimuli: the baby begins to understand that when the mother speaks to him and approaches him, most likely she will take him in her arms or feed him. That is, a person forms a complex form of behavior. His crying will draw attention to him, and he uses this reaction consciously.

sexual reflex

But this reflex belongs to the unconscious and unconditioned, it is aimed at procreation. It occurs during puberty, that is, only when the body is ready for procreation. Scientists say that this reflex is one of the strongest, it determines the complex behavior of a living organism and subsequently triggers the instinct to protect its offspring. Despite the fact that all these reactions are inherently human, they are launched in a certain order.

Conditioned reflexes

In addition to the instinctive reactions that we have at birth, a person needs many other skills in order to better adapt to the world around him. Acquired behavior is formed both in animals and in humans throughout life, this phenomenon is called "conditioned reflexes". Examples: at the sight of food, salivation occurs, while observing the diet, there is a feeling of hunger at a certain time of the day. Such a phenomenon is formed by a temporary connection between the center or vision) and the center of the unconditioned reflex. An external stimulus becomes a signal for a certain action. Visual images, sounds, smells are able to form stable connections and give rise to new reflexes. When someone sees a lemon, salivation may begin, and with a sharp smell or contemplation of an unpleasant picture, nausea occurs - these are examples of conditioned reflexes in humans. Note that these reactions can be individual for each living organism, temporary connections are formed in the cerebral cortex and send a signal when an external stimulus occurs.

Throughout life, conditioned responses can come and go. Everything depends on For example, in childhood, a child reacts to the sight of a bottle of milk, realizing that this is food. But when the baby grows up, this object will not form an image of food for him, he will react to a spoon and a plate.

Heredity

As we have already found out, unconditioned reflexes are inherited in every species of living beings. But conditioned reactions affect only the complex behavior of a person, but are not transmitted to descendants. Each organism "adjusts" to a particular situation and the reality surrounding it. Examples of innate reflexes that do not disappear throughout life: eating, swallowing, reaction to the taste of the product. Conditioned stimuli change constantly depending on our preferences and age: in childhood, at the sight of a toy, the baby experiences joyful emotions; in the process of growing up, the reaction is caused, for example, by visual images of a film.

Animal reactions

Animals, like humans, have both unconditioned innate reactions and acquired reflexes throughout their lives. In addition to the instinct of self-preservation and the production of food, living beings also adapt to the environment. They develop a reaction to the nickname (pets), with repeated repetition, an attention reflex appears.

Numerous experiments have shown that it is possible to instill in a pet many reactions to external stimuli. For example, if at each feeding you call the dog with a bell or a certain signal, he will have a strong perception of the situation, and he will immediately react. In the process of training, rewarding a pet for an executed command with a favorite treat forms a conditioned reaction, walking a dog and the type of leash signals an imminent walk where he should relieve himself are examples of reflexes in animals.

Summary

The nervous system constantly sends a lot of signals to our brain, they form the behavior of humans and animals. The constant activity of neurons allows us to perform habitual actions and respond to external stimuli, helping to better adapt to the world around us.

Each person, as well as all living organisms, has a number of vital needs: food, water, comfortable conditions. Everyone has the instincts of self-preservation and continuation of their kind. All mechanisms aimed at satisfying these needs are laid down at the genetic level and appear simultaneously with the birth of the organism. These are innate reflexes that help to survive.

The concept of an unconditioned reflex

The very word reflex for each of us is not something new and unfamiliar. Everyone has heard it in their life, and enough times. This term was introduced into biology by IP Pavlov, who devoted much time to the study of the nervous system.

According to the scientist, unconditioned reflexes arise under the influence of irritating factors on the receptors (for example, pulling the hand away from a hot object). They contribute to the adaptation of the organism to those conditions that remain practically unchanged.

This is the so-called product of the historical experience of previous generations, which is why it is also called the species reflex.

We live in a changing environment, it requires constant adaptations that cannot be foreseen by genetic experience. The unconditioned reflexes of a person are constantly inhibited, then modified or reappeared, under the influence of those stimuli that surround us everywhere.

Thus, already familiar stimuli acquire the qualities of biologically significant signals, and the formation of conditioned reflexes occurs, which form the basis of our individual experience. This is what Pavlov called higher nervous activity.

Properties of unconditioned reflexes

The characteristic of unconditioned reflexes includes several mandatory points:

1. Congenital reflexes are inherited.
2. They are the same in all individuals of this species.
3. For a response to occur, the influence of a certain factor is necessary, for example, for a sucking reflex, this is irritation of the lips of a newborn.
4. The zone of perception of the stimulus always remains constant.
5. Unconditioned reflexes have a constant reflex arc.
6. They persist throughout life, with some exceptions in newborns.

The meaning of reflexes

All our interaction with the environment is built on the level of reflex responses. Unconditioned and conditioned reflexes play an important role in the existence of the organism.

In the process of evolution, there was a division between those that are aimed at the survival of the species, and those responsible for adaptability to constantly changing conditions.

Congenital reflexes begin to appear already in utero, and their role is as follows:

• Maintaining the indicators of the internal environment at a constant level.
• Maintaining the integrity of the body.
• Preservation of the species through reproduction.

The role of innate reactions immediately after birth is great; it is they that ensure the survival of the infant in completely new conditions for him.

The body lives in an environment of external factors that are constantly changing, and it is necessary to adapt to them. This is where higher nervous activity comes to the fore in the form of conditioned reflexes.

For the body, they have the following meaning:

• Improve the mechanisms of its interaction with the environment.
• They clarify and complicate the processes of contacting the body with the external environment.
• Conditioned reflexes are an indispensable basis for the processes of learning, education and behavior.

Thus, unconditioned and conditioned reflexes are aimed at maintaining the integrity of a living organism and the constancy of the internal environment, as well as effective interaction with the outside world. Between themselves, they can be combined into complex reflex acts that have a certain biological orientation.

Classification of unconditioned reflexes

The hereditary reactions of the body, despite their innate nature, can be very different from each other. It is not at all surprising that the classification can be different, depending on the approach.

Pavlov also divided all unconditioned reflexes into:

• Simple (the scientist attributed the sucking reflex to them).
• Difficult (sweating).
• The most complex unconditioned reflexes. Examples can be given in a variety of ways: food reactions, defensive, sexual.

Currently, many adhere to a classification based on the meaning of reflexes. Depending on this, they are divided into several groups:

The first group of reactions has two features:

1. If they are not satisfied, then this will lead to the death of the body.
2. For satisfaction, there is no need for the presence of another individual of the same species.

The third group also has its own characteristic features:

1. Reflexes of self-development are in no way connected with the adaptation of the organism to a given situation. They are directed towards the future.
2. They are completely independent and do not follow from other needs.

You can also divide by the level of their complexity, then the following groups will appear before us:

1. simple reflexes. These are the body's normal responses to external stimuli. For example, pulling your hand away from a hot object or blinking when a mote gets into your eye.
2. reflex acts.
3. behavioral reactions.
4. instincts.
5. Imprinting.

Each group has its own characteristics and differences.

Reflex acts

Almost all reflex acts are aimed at ensuring the vital activity of the organism, therefore they are always reliable in their manifestation and cannot be corrected.

These include:

• Breath.
• swallowing.
• Vomit.

In order to stop the reflex act, you just need to remove the stimulus that causes it. This can be practiced in animal training. If you want natural needs not to distract from training, then before that you need to walk the dog, this will eliminate the irritant that can provoke a reflex act.

Behavior reactions

This variety of unconditioned reflexes can be well demonstrated in animals. Behavioral responses include:

• The desire of the dog to carry and pick up objects. Aportation reaction.
• The manifestation of aggression at the sight of a stranger. Active defensive reaction.
• Search for items by smell. Olfactory-search reaction.

It is worth noting that the reaction of behavior does not yet mean that the animal will certainly behave this way. What is meant? For example, a dog that has a strong active-defensive reaction from birth, but is physically weak, most likely will not show such aggression.

These reflexes can determine the actions of the animal, but it is quite possible to control them. They should also be taken into account when training: if an animal has no olfactory-search reaction at all, then it is unlikely that it will be possible to raise a search dog out of it.

instincts

There are also more complex forms in which unconditioned reflexes appear. Instincts are just here. This is a whole chain of reflex acts that follow each other and are inextricably linked.

All instincts are connected with changing inner needs.

When a baby is just born, his lungs practically do not function. The connection between him and his mother is interrupted by cutting the umbilical cord, and carbon dioxide accumulates in the blood. It begins its humoral action on the respiratory center, and an instinctive inhalation takes place. The child begins to breathe independently, and the first cry of the baby is a sign of this.

Instincts are a powerful stimulant in human life. They may well motivate for success in a certain field of activity. When we cease to control ourselves, then instincts begin to lead us. As you can imagine, there are several of them.

Most scientists are of the opinion that there are three basic instincts:

1. Self-preservation and survival.
2. Procreation.
3. Leader instinct.

All of them can give rise to new needs:

• In safety.
• In material abundance.
• Looking for a sexual partner.
• In caring for children.
• Influencing others.

You can still list the varieties of human instincts for a long time, but, unlike animals, we can control them. To do this, nature has endowed us with reason. Animals survive only due to instincts, but we are also given knowledge for this.

Don't let your instincts get the best of you, learn to control them and become the master of your life.

imprinting

This form of unconditioned reflex is also called imprinting. In the life of every individual there are periods when the whole environment is imprinted in the brain. For each species, this time period can be different: for some it lasts several hours, and for some it can take several years.

Remember how easy it is for young children to master the skills of foreign speech. While students put a lot of effort into this.

It is thanks to imprinting that all babies recognize their parents, distinguish individuals of their own species. For example, a zebra, after the birth of a cub, is alone with him for several hours in a secluded place. This is just the time it takes for the cub to learn to recognize its mother and not confuse her with other females in the herd.

This phenomenon was discovered by Konrad Lorenz. He conducted an experiment with newborn ducklings. Immediately after the hatching of the latter, he presented them with various objects, which they followed like a mother. Even they perceived him as a mother, and pursued him on his heels.

Everyone knows the example of hatchery chickens. Compared to their relatives, they are practically tame and are not afraid of a person, because from birth they see him in front of them.

Congenital reflexes of an infant

After his birth, the baby goes through a complex path of development, which consists of several stages. The degree and speed of mastering various skills will directly depend on the state of the nervous system. The main indicator of its maturity are the unconditioned reflexes of the newborn.

Their presence in the baby is checked immediately after birth, and the doctor makes a conclusion about the degree of development of the nervous system.

Of the huge number of hereditary reactions, the following can be distinguished:

1. Kussmaul's search reflex. When the area around the mouth is irritated, the child turns the head towards the irritant. Usually the reflex fades by 3 months.
2. Sucking. If you put your finger in the baby's mouth, then he begins to perform sucking movements. Immediately after feeding, this reflex fades away and is activated after a while.
3. Palmar-oral. If the child presses on the palm, then he opens his mouth.
4. Grasping reflex. If you put your finger in the palm of the baby and lightly press it, then there is a reflex squeezing and holding it.
5. The lower grasp reflex is elicited by light pressure on the front of the sole. There is flexion of the toes.
6. crawling reflex. In the prone position, pressure on the soles of the feet causes a forward crawling motion.
7. Protective. If you put the newborn on his stomach, he tries to raise his head and turns it to the side.
8. Support reflex. If you take the baby under the armpits and put it on something, then it reflexively unbends the legs and rests on the whole foot.

The unconditioned reflexes of a newborn can be listed for a long time. Each of them symbolizes the degree of development of certain parts of the nervous system. Already after examination by a neurologist in the maternity hospital, it is possible to make a preliminary diagnosis of some diseases.

From the point of view of their significance for the baby, the mentioned reflexes can be divided into two groups:

1. Segmental motor automatisms. They are provided by segments of the brain stem and spinal cord.
2. Posotonic automatisms. Provides regulation of muscle tone. The centers are located in the middle and medulla oblongata.

Oral segmental reflexes

These types of reflexes include:

• Sucking. It appears during the first year of life.
• Search. Fading occurs at 3-4 months.
• Proboscis reflex. If you hit the baby with a finger on the lips, then he pulls them into the proboscis. After 3 months, fading occurs.
• The palmar-mouth reflex well shows the development of the nervous system. If it does not manifest itself or is very weak, then we can talk about the defeat of the central nervous system.

Spinal motor automatisms

Many unconditioned reflexes belong to this group. Examples include the following:

• Moro reflex. When a reaction is evoked, for example, by hitting the table not far from the baby's head, the latter's arms are spread to the sides. Appears up to 4-5 months.
• Automatic gait reflex. With support and a slight tilt forward, the baby makes stepping movements. After 1.5 months it starts to fade.
• Reflex Galant. If you run your finger along the paravertebral line from the shoulder to the buttocks, then the torso flexes towards the stimulus.

Unconditioned reflexes are evaluated on a scale: satisfactory, increased, decreased, absent.

Differences between conditioned and unconditioned reflexes

Sechenov also argued that under the conditions in which the organism lives, it is completely insufficient for the survival of innate reactions, the development of new reflexes is required. They will contribute to the adaptation of the body to changing conditions.

How do unconditioned reflexes differ from conditioned ones? The table shows this well.

Despite the obvious difference between conditioned reflexes and unconditioned ones, together these reactions ensure the survival and preservation of the species in nature.

A reflex is the body's response to an internal or external stimulus, carried out and controlled by the central nervous system. The first scientists who developed ideas about human behavior, which had previously been a mystery, were our compatriots I.P. Pavlov and I.M. Sechenov.

What are unconditioned reflexes?

An unconditioned reflex is an innate stereotyped reaction of the body to the influence of the internal or environment, inherited from the offspring from the parents. It remains with a person throughout his life. Reflex arcs pass through the brain and spinal cord, the cerebral cortex does not take part in their formation. The significance of the unconditioned reflex is that it ensures the adaptation of the human body directly to those changes in the environment that often accompanied many generations of his ancestors.

What reflexes are unconditioned?

The unconditioned reflex is the main form of activity of the nervous system, ...

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A reflex is a stereotypical (monotonous, repeating in the same way) response of the body to the action of stimuli with the mandatory participation of the central nervous system.

Reflexes are divided into unconditional and conditional.

Unconditioned reflexes include:

1. Reflexes aimed at preserving the species. They are the most biologically significant, prevail over other reflexes, are dominant in a competitive situation, namely: sexual reflex, parental reflex, territorial reflex (this is the protection of one's territory; this reflex is manifested in both animals and humans), hierarchical reflex (the principle of subordination is reflexively embedded in a person, i.e. we are ready to obey, but we also want to command too - relations in society are built on this, but there is also a biological basis here).

2. Self-preservation reflexes, They are aimed at preserving the individual, personality, individual: drinking reflex, food reflex, defensive reflex, aggressiveness reflex (attack is the best ...

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Differences between conditioned reflexes and unconditioned ones. Unconditioned reflexes are innate reactions of the body, they were formed and fixed in the process of evolution and are inherited. Conditioned reflexes arise, are fixed, fade away during life and are individual. Unconditioned reflexes are species-specific, that is, they are found in all individuals of a given species. Conditioned reflexes may be developed in some individuals of a given species, while others may be absent; they are individual. Unconditioned reflexes do not require special conditions for their occurrence; they necessarily arise if adequate stimuli act on certain receptors. Conditioned reflexes require special conditions for their formation; they can be formed to any stimuli (of optimal strength and duration) from any receptive field. Unconditioned reflexes are relatively constant, persistent, unchanging and persist throughout life. Conditioned reflexes are changeable and more mobile.
Unconditional...

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Unconditioned reflexes are constant innate reactions of the body to certain influences of the external world, carried out through the nervous system and not requiring special conditions for their occurrence.

All unconditioned reflexes, according to the degree of complexity and severity of the body's reactions, are divided into simple and complex; depending on the type of reaction - to food, sexual, defensive, tentative-research, etc.; depending on the attitude of the animal to the stimulus - into biologically positive and biologically negative. Unconditioned reflexes arise mainly under the influence of contact stimulation: food unconditioned reflex - when food enters the mouth and its effect on the receptors of the tongue; defensive - with irritation of pain receptors. However, the occurrence of unconditioned reflexes is also possible under the influence of such stimuli as the sound, sight and smell of an object. So, the unconditioned sexual reflex occurs under the influence of a specific sexual stimulus (view, ...

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Physiology of higher nervous activity Congenital forms of behavior. unconditioned reflexes.

Unconditioned reflexes are innate responses of the body to irritation. Properties of unconditioned reflexes:

1. They are innate, i.e. inherited

2. Inherited by all representatives of this species of animals

3. For the occurrence of an unconditional reflex reaction, the action of a specific stimulus is necessary (mechanical irritation of the lips, a sucking reflex in a newborn)

4. They have a constant receptive field (a zone of perception of a specific stimulus).

5. They have a constant reflex arc.

I.P. Pavlov divided all unconditioned reflexes (B.U.R.) into simple (sucking), complex (sweating) and complex (food, defensive, sexual, etc.). Currently, all unconditioned reflexes, depending on their value, are divided into 3 groups:

1. Vital (vital). They ensure the preservation of the individual. To them...

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Each person, as well as all living organisms, has a number of vital needs: food, water, comfortable conditions. Everyone has the instincts of self-preservation and continuation of their kind. All mechanisms aimed at satisfying these needs are laid down at the genetic level and appear simultaneously with the birth of the organism. These are innate reflexes that help to survive.

The concept of an unconditioned reflex

The very word reflex for each of us is not something new and unfamiliar. Everyone has heard it in their life, and enough times. This term was introduced into biology by IP Pavlov, who devoted much time to the study of the nervous system.

According to the scientist, unconditioned reflexes arise under the influence of irritating factors on the receptors (for example, pulling the hand away from a hot object). They contribute to the adaptation of the organism to those conditions that remain practically unchanged.

This is the so-called product of historical...

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Pull your hand away from a hot kettle, close your eyes at a flash of light... We perform such actions automatically, without having time to think about what exactly we are doing and why. These are the unconditioned human reflexes - innate reactions that are characteristic of all people without exception.

History of discovery, types, differences

Before considering unconditioned reflexes in detail, we will have to make a short digression into biology and talk about reflex processes in general.

So what is a reflex? In psychology, this is the response of the body to a change in the external or internal environment, which is carried out with the help of the central nervous system. Thanks to this ability, the body quickly adapts to changes in the surrounding world or in its internal state. For its implementation, a reflex arc is necessary, that is, the path along which the signal of irritation passes from the receptor to the corresponding organ.

For the first time, reflex reactions were described by Rene Descartes in the 17th century.

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Features of unconditioned 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 have not read the article on irritants, then be sure to read it first, and then proceed to this material). Unconditioned reflexes are divided into simple (food, defensive, sexual, visceral, tendon) and complex reflexes (instincts, emotions). Some researchers...

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Types of conditioned reflexes

Depending on the characteristics of the responses, the nature of the stimuli, the conditions for their application and reinforcement, etc., various types of conditioned reflexes are distinguished. These types are classified based on various criteria, in accordance with the tasks. Some of these classifications are of great importance both in theoretical and practical terms, including in sports activities.

Natural (natural) and artificial conditioned reflexes. Conditioned reflexes that form to the action of signals characterizing the constant properties of unconditioned stimuli (for example, the smell or type of food) are called natural conditioned reflexes.

An illustration of the regularities in the formation of natural conditioned reflexes are the experiments of I. S. Tsitovich. In these experiments, puppies of the same litter were kept on different diets: some were fed only meat, others only milk. In animals that have been fed meat, the sight and smell of it...

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Reflex (from lat. reflexus - reflected) - a stereotyped reaction of a living organism to a certain effect, taking place with the participation of the nervous system. According to the generally accepted classification, reflexes are divided into unconditional and conditional.

Unconditioned reflexes are innate, characteristic of a given species, responses to environmental influences.

1. Vital (vital). The instincts of this group ensure the preservation of the life of the individual. They are characterized by the following features:

a) failure to satisfy the corresponding need leads to the death of the individual; and

b) no other individual of this species is needed to satisfy a particular need.

Vital instincts include:

food,

Drinking,

Defensive,

Sleep-wake regulation

Economy reflex...

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Classification of unconditioned reflexes

I.P. Pavlov at one time divided unconditioned reflexes into three groups: simple, complex and most complex unconditioned reflexes. Among the most complex unconditioned reflexes, he singled out the following: 1) individual - food, active and passive-defensive, aggressive, freedom reflex, exploratory, game reflex; 2) specific - sexual and parental. According to Pavlov, the first of these reflexes ensure the individual self-preservation of the individual, the second - the preservation of the species.

P.V. Simonov identified 3 classes of reflexes:

1. Vital unconditioned reflexes provide individual and species preservation

organism. These include food, drink, sleep regulation, a defensive and orienting reflex (the "biological caution" reflex), a reflex to save strength, and many others. The criteria for the reflexes of the vital group are as follows: 1) dissatisfaction of the corresponding need leads to the physical death of the individual and 2) realization ...

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Classification of reflexes. What are the reflexes.

The functioning of the nervous system is based on the inseparable unity of congenital and acquired forms of adaptation, i.e. unconditioned and conditioned reflexes.

Unconditioned reflexes are congenital, relatively constant species reactions of the body, carried out through the nervous system in response to the action of certain stimuli. They ensure the coordinated activity of various functional systems of the body, aimed at maintaining its homeostasis and interaction with the environment. Examples of simple unconditioned reflexes can be knee, blinking, swallowing and others.

There is a large group of complex unconditioned reflexes: self-preservation, food, sexual, parental (caring for offspring), migratory, aggressive, locomotor (walking, running, flying, swimming), etc. Such reflexes are called instincts. They underlie the innate behavior of animals and represent ...

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Unconditioned reflexes - what is it and what is their role?

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 of special conditions, this is ...

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Differences between conditioned reflexes and unconditioned ones. Unconditioned reflexes are innate reactions of the body, they were formed and fixed in the process of evolution and are inherited. Conditioned reflexes arise, are fixed, fade away during life and are individual. Unconditioned reflexes are species-specific, that is, they are found in all individuals of a given species. Conditioned reflexes may be developed in some individuals of a given species, while others may be absent; they are individual. Unconditioned reflexes do not require special conditions for their occurrence; they necessarily arise if adequate stimuli act on certain receptors. Conditioned reflexes require special conditions for their formation; they can be formed to any stimuli (of optimal strength and duration) from any receptive field. Unconditioned reflexes are relatively constant, persistent, unchanging and persist throughout life. Conditioned reflexes are changeable and more mobile.

Unconditioned reflexes can be carried out at the level of the spinal cord and brain stem. Conditioned reflexes can be formed in response to any signals perceived by the body and are predominantly a function of the cerebral cortex, implemented with the participation of subcortical structures.

Unconditioned reflexes can ensure the existence of the organism only at the very early stage of life. The adaptation of the organism to constantly changing environmental conditions is ensured by conditioned reflexes developed throughout life. Conditioned reflexes are changeable. In the process of life, some conditioned reflexes, losing their meaning, fade away, others are developed.

Biological significance of conditioned reflexes. An organism is born with a certain fund of unconditioned reflexes. They provide him with the maintenance of life in relatively constant conditions of existence. These include unconditioned reflexes: food (chewing, sucking, swallowing, separation of saliva, gastric juice, etc.), defensive (pulling the hand away from a hot object, coughing, sneezing, blinking when a jet of air enters the eye, etc.), sexual reflexes (reflexes associated with sexual intercourse, feeding and caring for offspring), thermoregulatory, respiratory, cardiac, vascular reflexes that maintain the constancy of the internal environment of the body (homeostasis), etc.

Conditioned reflexes provide a more perfect adaptation of the body to changing conditions of life. They help to find food by smell, timely escape from danger, orientation in time and space. The conditioned reflex separation of saliva, gastric, pancreatic juices in appearance, smell, meal time creates the best conditions for the digestion of food even before it enters the body. An increase in gas exchange and an increase in pulmonary ventilation before the start of work, only at the sight of the environment in which the work is performed, contributes to greater endurance and better performance of the body during muscle activity.

Under the action of a conditioned signal, the cerebral cortex provides the body with a preliminary preparation for responding to those environmental stimuli that will have their effect in the future. Therefore, the activity of the cerebral cortex is a signal.

Conditions for the formation of a conditioned reflex. Conditioned reflexes are developed on the basis of unconditioned ones. The conditioned reflex is so named by I.P. Pavlov because certain conditions are needed for its formation. First of all, you need a conditioned stimulus, or signal. A conditioned stimulus can be any stimulus from the external environment or a certain change in the internal state of the organism. In the laboratory of I.P. Pavlov, a flashing light bulb, a bell, gurgling water, skin irritation, taste, olfactory stimuli, the sound of dishes, the sight of a burning candle, etc. were used as conditioned stimuli. Conditioned reflexes are developed for a while in a person subject to the work regime meals at the same time, a constant bedtime.

A conditioned reflex can be developed by combining an indifferent stimulus with a previously developed conditioned reflex. In this way, conditioned reflexes of the second order are formed, then it is necessary to reinforce the indifferent stimulus with a conditioned stimulus of the first order. It was possible to form conditioned reflexes of the third and fourth orders in the experiment. These reflexes are usually unstable. The children managed to develop reflexes of the sixth order.

The possibility of developing conditioned reflexes is hindered or completely excluded by strong extraneous stimuli, illness, etc.

In order to develop a conditioned reflex, the conditioned stimulus must be reinforced with an unconditioned stimulus, that is, one that causes an unconditioned reflex. The ringing of knives in the dining room will cause salivation in a person only if this ringing was reinforced by food one or more times. The ringing of knives and forks in our case is a conditioned stimulus, and the unconditioned stimulus that causes a salivary unconditioned reflex is food. The sight of a burning candle can become a signal for a child to withdraw his hand only if at least once the sight of a candle coincided with the pain of a burn. When a conditioned reflex is formed, the conditioned stimulus must precede the action of the unconditioned stimulus (usually by 1-5 s).

The mechanism of formation of a conditioned reflex. According to the ideas of IP Pavlov, the formation of a conditioned reflex is associated with the establishment of a temporary connection between two groups of cortical cells: between those who perceive conditioned and those who perceive unconditioned stimulation. This connection becomes stronger, the more often both parts of the cortex are simultaneously excited. After several combinations, the connection is so strong that under the action of only one conditioned stimulus, excitation also occurs in the second focus (Fig. 15).

Initially, an indifferent stimulus, if it is new and unexpected, causes a general generalized reaction of the body - an orienting reflex, which I.P. Pavlov called research or the “what is it?” reflex. Any stimulus, if it is used for the first time, causes a motor reaction (general startle, turning of the eyes, ears towards the stimulus), increased breathing, heartbeat, generalized changes in the electrical activity of the brain - the alpha rhythm is replaced by rapid fluctuations (beta rhythm). These reactions reflect the general generalized excitation. When the stimulus is repeated, if it does not become a signal for a certain activity, the orienting reflex fades. For example, if a dog hears a bell for the first time, it will give a general orienting reaction to it, but it will not salivate. Let's back up the sounding bell with food. In this case, two foci of excitation will appear in the cerebral cortex - one in the auditory zone, and the other in the food center (these are areas of the cortex that are excited under the influence of the smell, taste of food). After several reinforcements of the call with food in the cerebral cortex, a temporary connection will arise (close) between the two foci of excitation.

In the course of further research, facts were obtained indicating that the closure of the temporary connection occurs not only along the horizontal fibers (bark - bark). Gray matter incisions were used to separate different areas of the cortex in dogs, but this did not prevent the formation of temporary connections between the cells of these areas. This gave grounds to believe that the pathways cortex - subcortex - cortex also play an important role in establishing temporary connections. At the same time, centripetal impulses from a conditioned stimulus through the thalamus and a nonspecific system (hippocampus, reticular formation) enter the corresponding cortical zone. Here they are processed and reach the subcortical formations along the descending paths, from where the impulses come again to the cortex, but already in the zone of representation of the unconditioned reflex.

What happens in the neurons involved in the formation of a temporary connection? There are different points of view on this matter. One of them assigns the main role to morphological changes in the endings of the nerve processes.

Another point of view on the mechanism of the conditioned reflex is based on the principle of dominant A. A. Ukhtomsky. In the nervous system at each moment of time there are dominant foci of excitation - dominant foci. The dominant focus tends to attract to itself the excitation that enters other nerve centers, and thereby intensify. For example, during hunger, a persistent focus with increased excitability appears in the corresponding parts of the central nervous system - a food dominant. If a hungry puppy is allowed to lap milk and at the same time begins to irritate the paw with an electric current, then the puppy does not withdraw the paw, but begins to lap with even greater intensity. In a well-fed puppy, stimulation of the paw with an electric current causes a reaction of its withdrawal.

It is believed that during the formation of a conditioned reflex, the focus of persistent excitation that has arisen in the center of the unconditioned reflex "attracts" to itself the excitation that has arisen in the center of the conditioned stimulus. As these two excitations combine, a temporary connection is formed.

Many researchers believe that the change in protein synthesis plays a leading role in fixing the temporal connection; specific protein substances associated with the imprinting of a temporal connection are described. The formation of a temporary connection is associated with the mechanisms of storage of traces of excitation. However, the mechanisms of memory cannot be reduced to the mechanisms of “belt connection.

There are data on the possibility of saving traces at the level of single neurons. Cases of imprinting from a single action of an external stimulus are well known. This gives reason to believe that the closure of a temporary connection is one of the mechanisms of memory.

Inhibition of conditioned reflexes. Conditioned reflexes are plastic. They can persist for a long time, or they can slow down. Two types of inhibition of conditioned reflexes are described - internal and external.

Unconditional, or external, inhibition. This type of inhibition occurs when a new, sufficiently strong focus of excitation arises in the cerebral cortex during the implementation of the conditioned reflex, which is not associated with this conditioned reflex. If a dog has developed a conditioned salivary reflex to the sound of a bell, then turning on a bright light at the sound of a bell in this dog inhibits the previously developed salivation reflex. This inhibition is based on the phenomenon of negative induction: a new strong focus of excitation in the cortex from extraneous stimulation causes a decrease in excitability in the areas of the cerebral cortex associated with the implementation of the conditioned reflex, and, as a result of this phenomenon, inhibition of the conditioned reflex occurs. Sometimes this inhibition of conditioned reflexes is called induction inhibition.

Inductive inhibition does not require development (that is why it belongs to unconditioned inhibition) and develops immediately as soon as an external stimulus, extraneous for a given conditioned reflex, acts.

External braking also includes limiting braking. It manifests itself with an excessive increase in the strength or duration of the action of the conditioned stimulus. In this case, the conditioned reflex weakens or completely disappears. This inhibition is of protective importance, since it protects nerve cells from stimuli of too great strength or duration, which could disrupt their activity.

Conditional, or internal, inhibition. Internal inhibition, in contrast to external inhibition, develops within the arc of the conditioned reflex, i.e., in those nervous structures that are involved in the implementation of this reflex.

If external inhibition occurs immediately, as soon as the inhibitory agent has acted, then internal inhibition must be developed, it occurs under certain conditions, and this sometimes takes a long time.

One of the types of internal inhibition is extinction. It develops if many times the conditioned reflex is not reinforced by an unconditioned stimulus.

Some time after extinction, the conditioned reflex can be restored. This will happen if we again reinforce the action of the conditioned stimulus with an unconditioned one.

Fragile conditioned reflexes are restored with difficulty. Fading can explain the temporary loss of labor skill, the skill of playing musical instruments.

Decay is much slower in children than in adults. That is why it is difficult to wean children from bad habits. Fading is at the root of forgetting.

The extinction of conditioned reflexes is of great biological importance. Thanks to him, the body stops responding to signals that have lost their meaning. No matter how many unnecessary, superfluous movements a person would make during writing, labor operations, sports exercises without fading inhibition!

The delay of conditioned reflexes also refers to internal inhibition. It develops if the reinforcement of the conditioned stimulus by the unconditioned stimulus is set aside in time. Usually, when developing a conditioned reflex, they turn on a conditioned stimulus-signal (for example, a bell), and after 1-5 seconds they give food (unconditioned reinforcement). When the reflex is developed, immediately after turning on the bell, without giving food, saliva already begins to flow. Now let's do this: turn on the bell, and gradually move the food reinforcement in time up to 2-3 minutes after the start of the bell. After several (sometimes very multiple) combinations of a sounding bell with a delayed food reinforcement, a delay develops: the bell turns on, and saliva will now flow not immediately, but 2-3 minutes after the bell is turned on. Due to non-reinforcement for 2-3 minutes of the conditioned stimulus (bell) by the unconditioned stimulus (food), the conditioned stimulus acquires inhibitory significance during the time of non-reinforcement.

Delay creates conditions for better orientation of the animal in the surrounding world. The wolf does not immediately rush to the hare, seeing him at a considerable distance. He waits for the hare to approach. From the moment when the wolf saw the hare, until the time when the hare approached the wolf, the process of internal inhibition takes place in the cerebral cortex of the wolf: motor and food conditioned reflexes are inhibited. If this did not happen, the wolf would often be left without prey, breaking into the chase as soon as he sees the hare. The developed delay provides the wolf with prey.

Delay in children is developed with great difficulty under the influence of education and training. Remember how the first grader impatiently stretches his hand, waving it, getting up from his desk so that the teacher notices him. And only by the senior school age (and even then not always) we note endurance, the ability to restrain our desires, willpower.

Similar sound, olfactory and other stimuli can signal completely different events. Only an accurate analysis of these similar stimuli provides biologically appropriate responses of the animal. The analysis of stimuli consists in distinguishing, separating different signals, differentiating similar interactions on the organism. In the laboratory of IP Pavlov, for example, it was possible to develop such a differentiation: 100 beats of the metronome per minute were reinforced with food, and 96 beats were not reinforced. After several repetitions, the dog distinguished 100 beats of the metronome from 96: saliva flowed for 100 beats, and saliva did not separate for 96 beats. The inhibition that develops at the same time suppresses the reflex reaction to unreinforced stimuli. Differentiation is one of the types of conditional (internal) inhibition.

Thanks to differential inhibition, signal-significant signs of the stimulus can be distinguished from the many sounds, objects, faces, etc. that surround us. Differentiation is developed in children from the first months of life.

dynamic stereotype. The external world acts on the organism not by single stimuli, but usually by a system of simultaneous and successive stimuli. If this system is often repeated in this order, then this leads to the formation of a dynamic stereotype.

A dynamic stereotype is a sequential chain of conditioned reflex acts that are carried out in a strictly defined order fixed in time and are the result of a complex systemic reaction of the body to a complex of conditioned stimuli. Thanks to the formation of chain conditioned reflexes, each previous activity of the organism becomes a conditioned stimulus - a signal for the next one. Thus, the previous activity prepares the body for the next one. A manifestation of a dynamic stereotype is a conditioned reflex to time, which contributes to the optimal activity of the body with the correct daily routine. For example, eating at certain hours ensures a good appetite and normal digestion; Consistent adherence to bedtime helps children and adolescents fall asleep quickly and, thus, sleep longer; the implementation of educational work and labor activity always at the same hours leads to faster development of the body and better assimilation of knowledge, skills, and abilities.

A stereotype is difficult to develop, but if it is developed, then maintaining it does not require significant stress on cortical activity, and many actions become automatic. ;d The dynamic stereotype is the basis for the formation of habits in a person, the formation of a certain sequence in labor operations, the acquisition of skills and abilities.

Walking, running, jumping, skiing, playing the piano, eating with a spoon, fork, knife, writing - all these are skills based on the formation of dynamic stereotypes in the cerebral cortex.

The formation of a dynamic stereotype underlies the daily routine of each person. Stereotypes persist for many years and form the basis of human behavior. Stereotypes that have arisen in early childhood are very difficult to change. Let us recall how difficult it is to “retrain” a child if he has learned to hold a pen incorrectly when writing, to sit incorrectly at a table, etc. The difficulty of reshaping stereotypes forces one to pay special attention to the correct methods of raising and teaching children from the first years of life.

The dynamic stereotype is one of the manifestations of the systemic organization of higher cortical functions aimed at ensuring stable reactions of the body.

In the body of an animal there is a continuous metabolism, as a result of which there is a need for food, water, etc. The need that has arisen causes purposeful behavior to satisfy it.

Feelings of fear, cold, or other causes also cause the animal to react in a certain way to environmental stimuli. All of these reactions are innate. They are inherited and appear in every animal. Such persistently inherited innate responses of the organism to stimuli of the internal and external environment are called unconditioned reflexes.

Congenital unconditioned reflexes can be simple (constriction or dilation of the pupils under the influence of light, withdrawal of the paw when pricked, blinking reflex) and more complex. More complex reflexes are called instincts.

All instincts are divided into two main groups:

1) self-preservation instincts: food, defensive, orienting, imitation, herd, cleanliness, reflex struggle with restrictions (freedom reflex), goal reflex, game instinct, etc .;

2) instincts aimed at preserving the race; sexual, parental.

Let's take a closer look at some of these instincts.

The goal reflex is expressed in the fact that if a motor act has begun, then its completion is required. The dog tries to master the irritating object. This reflex is based on the development of the dog's grip. Or some other phenomenon. Dog lovers know how a dog resists the first time they try to muzzle it. This is the fight against restrictions - a manifestation of the reflex of freedom. The orienting reflex, which occurs to any change in the environment, to each new stimulus (sound, olfactory, etc.), is expressed in the movement of the eyes, the turn of the ears, the head, and sometimes the entire body in the direction of the stimulus, as well as in listening, in sniffing, examining this stimulus. Depending on the nature of the stimulus, the orienting reflex can then be replaced by a defensive, food, play or other one, and also, unlike other unconditioned reflexes, it can die out with repeated action of a stimulus that is not important for the body.

Unlike simple unconditioned reflexes, complex unconditioned reflexes consist of a whole chain of simple ones. In a complex unconditioned reflex, the action of one reflex is a stimulus for another. For example, a bitch's concern for puppies manifests itself in a number of actions: she gnaws the umbilical cord at birth, licks the puppies, feeds them, warms them and protects them.

Thanks to instincts , formed by thousands of previous generations, newborn animals, already from the very birth, are able to respond to certain environmental influences with the same expedient behavior as their parents. But not all instincts are manifested in animals in the very first minutes of their life and do not remain for life. A dog suffering from helminths (worms) begins to eat Chernobyl, which he usually does not touch - here the expedient inherited reaction makes itself felt only under specific conditions, regardless of the age of the animal. It may not appear if it is not needed. With age, the sexual instinct manifests itself in dogs; with the aging of the body, it disappears.
The degree and forms of manifestation of instincts depend not only on the physiological state of the organism, but also on the influence of the environment. As a result, the manifestation of instincts in an adult dog is always complicated by acquired experience. It suffices to compare the behavior of a newborn, aimed at finding food, and an adult animal. The search for the newborn is not certain, and the adult animal immediately rushes to the place where it has repeatedly satisfied this need.

Parents play an important role in the acquisition of skills by young animals. Parents teach their offspring to distinguish stimuli in a huge variety of environments that contribute to or, conversely, hinder the satisfaction of basic, vital needs. In the future, each animal replenishes its experience independently. Depending on the conditions of life, it develops many conditioned reflexes that help it more successfully satisfy its needs.
In dog training, the so-called complex unconditioned position reflexes are of great importance. These reflexes are usually understood as the actions of the dog, through which it assumes a certain position, for example, sits down, lies down, jumps.

Instinct- this is the adaptation of animals to strictly defined environmental conditions. Therefore, if conditions change, the animal, in order to adapt to them, needs to supplement instincts, make adjustments to behavior. In this regard, animals have developed the ability to learn, to use "personal" experience in behavior. This ability is based on a conditioned reflex, thanks to which training is possible.