Human behavior is associated with conditioned-unconditioned reflex activity and represents higher nervous activity, the result of which is a change in the relationship of the organism with the external environment.

Unlike the highest nervous activity lower nervous activity consists of a set of reactions aimed at unifying and integrating functions within the body.

Higher nervous activity manifests itself in the form of complex reflex reactions carried out with the obligatory participation of the cerebral cortex and the subcortical formations closest to it.

For the first time, the idea of ​​the reflex nature of brain activity was widely and in detail developed by the founder of Russian physiology I.M. Sechenov in his book “Reflexes of the Brain.” The ideological setting of this classic work is expressed in the original title, changed under the influence of censorship: “An attempt to introduce physiological basis into mental processes." Before I.M. Sechenov, physiologists and neurologists did not even dare to raise the question of the possibility of an objective, purely physiological analysis mental processes. The latter remained completely at the mercy of subjective psychology.

The ideas of I.M. Sechenov received brilliant development in the remarkable works of I.P. Pavlov, who opened the way for objective experimental research of the functions of the cerebral cortex and created a harmonious doctrine of higher nervous activity.

I. P. Pavlov showed that while in the underlying parts of the central nervous system - the subcortical nuclei, brain stem, 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 the individual life of animals and humans, as a result of a combination of countless irritations 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.

Conditioned reflexes

• These are reactions acquired by the body in the process individual development based " life experience"
• are individual: some representatives of the same species may have them, while others may not
• are unstable and, depending on certain conditions, they can develop, gain a foothold or disappear; this is their property and is reflected in their very name
• can be formed in response to a wide variety of stimuli applied to various receptive fields
• are closed at the level of the cortex. After removing the cerebral cortex, the developed conditioned reflexes disappear and only unconditioned ones remain.
• carried out through functional temporary connections

Conditioned reflexes are developed on the basis unconditioned reflexes. For the formation of a conditioned reflex, it is necessary to combine the time of any change in the external environment and the internal state of the body, perceived by the cerebral cortex, with the implementation of one or another unconditioned reflex. Only under this condition does a change in the external environment or internal state the body becomes a stimulus for a conditioned reflex - a conditioned stimulus, or signal. The irritation that causes an unconditioned reflex - unconditioned irritation - must, during the formation of a conditioned reflex, accompany the conditioned irritation and reinforce it.

For the formation of conditioned reflexes, it is necessary to create a temporary connection, a closure between the cortical cells that perceive conditioned stimulation and the cortical neurons that are part of the unconditioned reflex arc.

When conditioned and unconditioned stimulation coincide and combine, a connection is established between different neurons in the cerebral cortex and a process of closure occurs between them.

Unconditioned reflexes

• These are innate, hereditary reactions of the body
• are specific, i.e. characteristic of all representatives of a given species
• relatively constant, as a rule, persist throughout life
• carried out in response to adequate stimulation applied to one specific receptive field
• closes at the level of the spinal cord and brainstem
• are carried out through a phylogenetically fixed, anatomically expressed reflex arc.

It should be noted, however, that in humans and monkeys, who have high degree corticalization of functions, many complex unconditioned reflexes are carried out with the obligatory participation of the cerebral cortex. This is proven by the fact that its lesions in primates lead to pathological disorders 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 and sexual intercourse, arise in humans and animals long after birth, but they necessarily appear under the condition of normal development of the nervous system.

The entire set of unconditioned and conditioned reflexes formed on their basis is accepted according to their functional significance divided into a number of groups.

1. By receptor
   1. Exteroceptive reflexes
      • visual
      • olfactory
      • flavoring, etc.
   2. Interoreceptive reflexes- reflexes in which the conditioned stimulus is irritation of the receptors of internal organs by a change chemical composition, temperature of internal organs, pressure in hollow organs and vessels
2. By effector trait, i.e. by those effectors that respond to stimulation
   1. autonomic reflexes
      • food
      • cardiovascular
      • respiratory, etc.
   2. somato-motor reflexes- manifested in movements of the whole organism or its individual parts in response to a stimulus
      • defensive
3. According to biological significance
   1. Food
      • reflex act of swallowing
      • reflexive act of chewing
      • reflex act of sucking
      • reflex act of salivation
      • reflex act of secretion of gastric and pancreatic juice, etc.
   2. Defensive- reactions to eliminate damaging and painful stimuli
   3. Genital- reflexes associated with sexual intercourse; This group also includes the so-called parental reflexes associated with feeding and nursing the offspring.
   4. Stato-kinetic and locomotor- reflex reactions of maintaining a certain position and movement of the body in space.
   5. Reflexes for maintaining homeostasis
      • thermoregulation reflex
      • breathing reflex
      • cardiac reflex
      • vascular reflexes that help maintain constant blood pressure, etc.
   6. Orienting reflex- reflex to novelty. It occurs in response to any sufficiently rapid vibration. environment and is expressed externally in alertness, listening to a new sound, sniffing, turning the eyes and head, and sometimes the entire body towards the emerging light stimulus, etc. The implementation of this reflex provides a better perception of the active agent and has important adaptive significance.

      I. P. Pavlov figuratively called the indicative reaction the “what is it?” reflex. This reaction is innate and does not disappear with complete removal of the cerebral cortex in animals; it is also observed in children with underdeveloped cerebral hemispheres - anencephals.

The difference between the orienting reflex and other unconditioned reflex reactions is that it fades away relatively quickly with repeated applications of the same stimulus. This feature of the orientation reflex depends on the influence of the cerebral cortex on it.

The above classification of reflex reactions is very close to the classification of various instincts, which are also divided into food, sexual, parental, and defensive. This is understandable due to the fact that, according to I.P. Pavlov, instincts are complex unconditioned reflexes. Their distinctive features is the chain nature of the reactions (the end of one reflex serves as the trigger for the next) and their dependence on hormonal and metabolic factors. Thus, the emergence of sexual and parental instincts is associated with cyclical changes in the functioning of the gonads, and the food instinct depends on those metabolic changes that develop in the absence of food. One of the features of instinctive reactions is also that they are characterized by many properties of the dominant.

The reflex component is a reaction to irritation (movement, secretion, change in breathing, etc.).

Most unconditioned reflexes are complex reactions that include several components. So, for example, with an unconditioned defensive reflex, caused in a dog by strong electrocutaneous irritation of the limb, along with defensive movements, breathing also increases and increases, cardiac activity accelerates, vocal reactions appear (squealing, barking), the blood system changes (leukocytosis, platelets and etc.). The food reflex also distinguishes between its motor (grasping food, chewing, swallowing), secretory, respiratory, cardiovascular and other components.

Conditioned reflexes, as a rule, reproduce the structure of the unconditioned reflex, since the conditioned stimulus excites the same nerve centers as the unconditioned one. Therefore, the composition of the components of the conditioned reflex is similar to the composition of the components of the unconditioned reaction.

Among the components of a conditioned reflex, there are main, specific for a given type of reflex, and secondary components. In the defensive reflex the main component is the motor component, in the food reflex the main component is the motor and secretory ones.

Changes in respiration, cardiac activity, and vascular tone that accompany the main components are also important for the animal’s holistic response to a stimulus, but they play, as I. P. Pavlov said, “a purely auxiliary role.” Thus, increased and increased respiration, increased heart rate, increased vascular tone, caused by a conditioned defensive stimulus, contribute to increased metabolic processes in skeletal muscles and thereby create optimal conditions for the implementation of protective motor reactions.

When studying conditioned reflexes, the experimenter often chooses one of its main components as an indicator. That is why they talk about conditioned and unconditioned motor or secretory or vasomotor reflexes. It is necessary, however, to take into account that they represent only individual components of the body’s holistic reaction.

The biological significance of conditioned reflexes is that they make it possible to adapt much better and more accurately to the conditions of existence and to 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. In this way, the body is prepared in advance for the actions that it has to carry out in a given situation. Conditioned reflexes contribute to finding food, avoiding danger in advance, eliminating harmful effects and so on.

The adaptive significance of conditioned reflexes is also manifested in the fact that the precedence of conditioned stimulation by an unconditioned one strengthens the unconditioned reflex and accelerates its development.

Animal behavior is different shapes external, mainly motor activity aimed at establishing vital connections between the body and the environment. Animal behavior consists of conditioned, unconditioned reflexes and instincts. Instincts include complex unconditioned reactions, which, being innate, appear only during certain periods of life (for example, the instinct of nesting or feeding offspring). Instincts play a leading role in the behavior of lower animals. However, the higher an animal is at the evolutionary level, the more complex and varied its behavior, the more perfect and subtle it adapts to the environment, and the greater the role conditioned reflexes play in its behavior.

The environment in which animals exist is very variable. Adaptation to the conditions of this environment through conditioned reflexes will be subtle and accurate only if these reflexes are also changeable, that is, conditioned reflexes unnecessary in the new environmental conditions will disappear, and new ones will form in their place. The disappearance of conditioned reflexes occurs due to inhibition processes.

A distinction is made between external (unconditioned) inhibition of conditioned reflexes and internal (conditioned) inhibition.

External inhibition of conditioned reflexes 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.

Extremely strong or long-acting extraneous stimuli can cause extreme inhibition of reflexes.

Internal inhibition of conditioned reflexes occurs in the absence of reinforcement by an unconditioned stimulus of the received signal.

Internal inhibition does not occur immediately. As a rule, repeated use of a non-reinforced signal is required.

The fact that this is inhibition of the conditioned reflex, and not its destruction, is evidenced by the restoration of the reflex the next day, when the inhibition has passed. Various diseases, overwork, and overstrain cause a weakening of internal inhibition.

If a conditioned reflex is extinguished (not reinforced with food) for several days in a row, it may disappear completely.

There are several types of internal inhibition. The form of inhibition discussed above is called extinction inhibition. This inhibition underlies the disappearance of unnecessary conditioned reflexes.

Another type is differentiated (discriminating) inhibition.

A non-reinforced conditioned stimulus causes inhibition in the cortex and is called an inhibitory stimulus. Using the described technique, it was possible to determine the discriminative ability of different sense organs in animals.

The phenomenon of disinhibition. It is known that extraneous stimuli cause inhibition of conditioned reflexes. If an extraneous stimulus occurs during the action of an inhibitory stimulus, for example, during the action of a metronome at a frequency of 100 times per minute, as in the previous case, then this will cause the opposite reaction - saliva will flow. I.P. Pavlov called this phenomenon disinhibition and explained it by the fact that an extraneous stimulus, causing an orienting reflex, inhibits any other process that occurs in this moment in the centers of the conditioned reflex. If the inhibition process is inhibited, then all this leads to excitation and implementation of the conditioned reflex.

The phenomenon of disinhibition also indicates the inhibitory nature of the processes of discrimination and extinction of conditioned reflexes.

The meaning of conditional inhibition very large. Thanks to inhibition, a much better correspondence of the body's reaction to external conditions is achieved, and its adaptation to the environment is more perfect. The combination of two forms of a single nervous process - excitation and inhibition - and their interaction make it possible for the body to navigate in various complex situations and are the conditions for the analysis and synthesis of stimuli.

Reflex- the body's response is not external or internal stimulation, 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 conditioned.

Unconditioned reflexes- This innate reflexes, which are inherited by offspring from their parents and persist throughout a person’s life. The arcs of unconditioned reflexes pass through the spinal cord or brain stem. The cerebral cortex is not involved in their formation. Unconditioned reflexes are provided only to those environmental changes that have often been encountered by many generations of a given species.

These include:

Food (salivation, sucking, swallowing);
Defensive (coughing, sneezing, blinking, withdrawing your hand from a hot object);
Approximate (squinting of the eyes, turns);
Sexual (reflexes associated with reproduction and care of offspring).
The importance of unconditioned reflexes lies in the fact that thanks to them the integrity of the body is preserved, constancy is maintained and reproduction occurs. Already in a newborn child the simplest unconditioned reflexes are observed.
The most important of these is the sucking reflex. The stimulus of the sucking reflex is the touching of an object to the child’s lips (mother’s breast, pacifier, toy, finger). 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 exposed to strong light on the eyes.

Particularly pronounced unconditioned reflexes in various animals. Not only individual reflexes can be congenital, but also more complex shapes behaviors that are called instincts.

Conditioned reflexes– these are reflexes that are easily acquired by the body throughout life and are formed on the basis of an unconditioned reflex under the action of a conditioned stimulus (light, knock, time, etc.). I.P. Pavlov studied the formation of conditioned reflexes in dogs and developed a method for obtaining them. To develop a conditioned reflex, a stimulus is needed - a signal that triggers the 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 the centers of the unconditioned reflex. Now this unconditioned reflex is not carried out under the influence of completely new external signals. These stimuli from the surrounding world, to which we were indifferent, can now acquire vital significance. Throughout life, many conditioned reflexes are developed that form the basis of our life experience. But this vital experience has meaning only for a given individual and is not inherited by its descendants.

In a separate category conditioned reflexes distinguish motor conditioned reflexes developed during our lives, i.e. skills or automated actions. The meaning of these conditioned reflexes is to master new motor skills and develop new forms of movements. During his life, a person masters many special motor skills related to 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. The most successful way to master skills is through systematic exercises, correction of errors noticed in time, knowledge ultimate goal each exercise.

If you do not reinforce the conditioned stimulus with the unconditioned stimulus for some time, then inhibition of the conditioned stimulus occurs. But it doesn't disappear completely. When the experience is repeated, the reflex is restored very quickly. Inhibition is also observed when exposed to another stimulus of greater strength.

Unconditioned reflexes- These are innate, hereditarily transmitted reactions of the body. Conditioned reflexes- these are reactions acquired by the body in the process of individual development on the basis of “life experience”.

Unconditioned reflexes are specific, that is, characteristic of all representatives of a given species. Conditioned reflexes are individual: some representatives of the same species may have them, while others may not.

Unconditioned reflexes are relatively constant; conditioned reflexes are not constant and, depending on certain conditions, they can be developed, consolidated or disappear; This is their property and is reflected in their very name.

Unconditioned reflexes are carried out in response to adequate stimulation applied to one specific receptive field. Conditioned reflexes can be formed to a wide variety of stimuli applied to various receptive fields.

In animals with a developed cerebral cortex, conditioned reflexes are a function of the cerebral cortex. After removing the cerebral cortex, the developed conditioned reflexes disappear and only unconditioned ones remain. This indicates that in the implementation of unconditioned reflexes, in contrast to conditioned ones, the leading role belongs to the lower parts of the central nervous system - the subcortical nuclei, brain stem and spinal cord. It should be noted, however, that in humans and monkeys, who 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 proven by the fact that its lesions in primates lead to pathological disorders 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 and sexual intercourse, arise in humans and animals long after birth, but they necessarily appear under the condition of normal development of the nervous system. Unconditioned reflexes are part of the fund of reflex reactions strengthened in the process of phylogenesis and hereditarily transmitted.

Conditioned reflexes are developed on the basis of unconditioned reflexes. For the formation of a conditioned reflex, it is necessary to combine in time some kind of change in the external environment or the internal state of the body, perceived by the cerebral cortex, with the implementation of one or another unconditioned reflex. Only under this condition does a change in the external environment or internal state of the body become a stimulus to a conditioned reflex - a conditioned stimulus, or signal. The irritation that causes an unconditioned reflex - unconditioned irritation - must, during the formation of a conditioned reflex, accompany the conditioned irritation and reinforce it.

In order for the clinking of knives and forks in the dining room or the knocking of a cup from which a dog is fed to cause salivation in the first case in a person, in the second case in a dog, it is necessary to re-coincidence of these sounds with food - reinforcement of stimuli that are initially indifferent to salivary secretion by feeding , i.e., unconditional irritation of the salivary glands. Likewise, the flashing of an electric light bulb in front of a dog’s eyes or the sound of a bell will only cause conditioned reflex flexion of the paw if they are repeatedly accompanied by electrical irritation of the skin of the leg, causing an unconditioned flexion reflex whenever it is used.

Similarly, a child’s crying and his hands pulling away from a burning candle will be observed only if the sight of the candle first coincided at least once with the feeling of a burn. In all the above examples, external agents that are initially relatively indifferent - the clinking of dishes, the sight of a burning candle, the flashing of an electric light bulb, the sound of a bell - become conditioned stimuli if they are reinforced by unconditioned stimuli. Only under this condition do the initially indifferent signals of the external world become stimuli for a certain type of activity.

For the formation of conditioned reflexes, it is necessary to create a temporary connection, a closure between the cortical cells that perceive conditioned stimulation and the cortical neurons that are part of the unconditioned reflex arc.

Conditioned reflex — a complex adaptive reaction of the body that occurs due to the formation of a temporary neural connection (association) between a signal (conditioned) and reinforcing it with an unconditioned stimulus.

Conditioned reflexes are formed on the basis of innate unconditioned reflexes. Conditioned reflexes are individual, acquired reflex reactions that are produced on the basis of unconditioned reflexes. Their signs:

1. Acquired throughout the life of the organism.
2. They are not the same among representatives of the same species.
3. They do not have ready-made reflex arcs.
4. They are formed under certain conditions.
5. In their implementation, the main role belongs to the cortex big brain.
6. Changeable, easily arise and disappear easily depending on the conditions in which the body is located.

Conditions for the formation of conditioned reflexes:

1. The simultaneous action of two stimuli: indifferent for a given type of activity, which later becomes a conditioned signal, and an unconditioned stimulus, which causes a certain unconditioned reflex.
2. The action of the conditioned stimulus always precedes the action of the unconditioned (by 1-5 s.).
3. Reinforcement of the conditioned stimulus with the unconditioned must be repeated.
4. The unconditioned stimulus must be biologically strong, and the conditioned stimulus must have moderate optimal strength.
5. Conditioned reflexes are formed faster and easier in the absence of extraneous stimuli.

Conditioned reflexes can be produced not only on the basis of unconditioned ones, but also on the basis of previously acquired conditioned reflexes that have become quite strong. These are conditioned reflexes of the highest order. Conditioned reflexes are:

• natural - reflex reactions that are produced to changes in the environment, and always accompany the emergence of the unconditional. For example, the smell and appearance of food are natural signals of the food itself;
• artificial - conditioned reflexes produced in response to irritation, which have no natural relation to the unconditional reflex reaction. For example, salivation for a call or for a while.

The conditioned reflex method is a method for studying GNI. I. P. Pavlov drew attention to the fact that the activity of the higher parts of the brain is not only associated with the direct influence of stimuli that have biological significance for the body, but also depends on the conditions that accompany these irritations. For example, a dog begins to salivate not only when food enters its mouth, but also at the sight and smell of food, as soon as it sees the person who always brings it food. I.P. Pavlov explained this phenomenon by developing the method of conditioned reflexes. Using the method of conditioned reflexes, he conducted experiments on dogs with a fistula (stomy) of the excretory duct of the parotid salivary gland. The animal was offered two stimuli: food, a stimulus that has biological significance and causes salivation; the second is indifferent to the nutrition process (light, sound). These stimuli were combined in time so that the effect of light (sound) preceded the intake of food by several seconds. After a number of repetitions, saliva began to be released when the light bulb flashed and there was no food. Light (an indifferent stimulus) was called conditioned, since it is the condition under which food intake took place. A stimulus that has biological significance (food) is called unconditioned, and the physiological reaction of salivation, which occurs as a result of the action of a conditioned stimulus, is called a conditioned reflex.

To find out the mechanism of formation of conditioned reflexes, partial isolation of certain parts of the cerebral cortex and recording of the electrical activity of various brain structures during the action of unconditioned and conditioned stimuli are used.

I.P. Pavlov believed that with simultaneous action on two different analyzers in different sensitive areas of the cerebral hemispheres, excitation occurs, and over time, a connection is formed between them. For example, when a light bulb lights up and this stimulus is reinforced with food, excitation occurs in the cortical part of the visual analyzer, located in the occipital region of the cortex and excitation of the food center of the cerebral cortex - that is, in both cortical centers (visual and food), between which a nerve connection is formed. , which, with repeated combinations of these stimuli over time, becomes durable.

With conditioned reflexes, as with unconditioned reflexes, reverse afferentia occurs, that is, a signal that a conditioned reflex reaction has taken place. It allows the central nervous system to evaluate behavioral acts. Without such an assessment, subtle adaptation of behavior to constantly changing environmental conditions is impossible.

Studies of animals in which areas of the cortex were removed showed that conditioned reflexes could be developed in these animals. So, conditioned reflexes are formed as a result of the interaction of the cerebral cortex and subcortical centers. The structure of the reflex arc of a conditioned reflex is complex. Thus, in the formation of complex behavioral reactions, the cortex has leading value, and in the formation of vegetative conditioned reflexes, the cortex and subcortical structures play the same role. It has been proven that the destruction of the reticular formation delays the formation of conditioned reflexes, and its irritation electric shock accelerates their formation. What are the signals of the conditioned reflex? Any changes in the environment or internal state of the body can become a conditioned stimulus if they:

1. they themselves do not cause an unconditioned reflex; they are indifferent.
2. their strength is sufficient to evoke an unconditioned orienting reflex.

For example, sounds, light, colors, smells, tastes, touch, pressure, heat, cold, body position in space - all these and others "indifferent" stimuli, when combined with an unconditioned stimulus and provided they are of sufficient strength, become signals that evoke one or another unconditioned reflex.

Biological significance of conditioned reflexes

The biological significance of conditioned reflexes lies in the fact that they are adaptive reactions of the body, which are formed by the living conditions of a person and make it possible to adapt in advance to new conditions. Conditioned reflexes have a warning signal value, since the body begins to react purposefully before a vital stimulus begins to act. Therefore, conditioned reflexes provide a living creature with the opportunity to assess danger or a red stimulus in advance, as well as the ability to carry out purposeful actions and consciously avoid mistakes.

10 questions in biology on the topic: unconditioned and conditioned reflexes.

1. What are unconditioned reflexes? "Unconditioned reflexes" - These are specific, innate, relatively constant reactions of the body to the influence of the external and internal environment, carried out with the help of the nervous system.
2. What are the main types of unconditioned reflexes? The main types of unconditioned reflexes include respiratory, food, grasping, protective, orientation and sexual.
3. What are instincts? A complex system of innate (insanely reflexive) behavior programs associated with the preservation of the species is called instincts (from the Latin instinctus - urge, motive).
4. What are conditioned reflexes? Conditioned reflexes, in contrast to unconditioned ones, are individual, arise during a person’s life, and are characteristic only of it; are temporary and may decline with changing environmental conditions.
5. What conditions are needed for the formation of conditioned reflexes? Conditioned reflexes are formed on the basis of unconditioned ones.
6. The mechanism of formation of conditioned reflexes? I.P. Pavlov found that the formation of conditioned reflexes is based on the establishment of temporary connections in the cerebral cortex between the nerve centers of the unconditioned reflex and the conditioned stimulus.
7. What are the types of conditioned reflexes? natural - reflex reactions that are produced to changes in the environment, and always accompany the emergence of the unconditional. For example, the smell and appearance of food are natural signals of the food itself; artificial - conditioned reflexes produced in response to irritation, which have no natural relation to the unconditional reflex reaction. For example, salivation for a call or for a while.
8. Examples of unconditioned reflexes: blinking, breathing, reaction to sounds (indicative reflex), knee reflex.
9. Examples of conditioned reflexes for recognizing food by smell, the processes of standing, running, walking, speaking, writing, and labor actions.
10. Defensive reflexes are
    1. Unconditional.
    2. Conditional (conditional play a lesser role in defense)

Reflex- This is the body’s response to irritation of receptors, carried out by the nervous system. The path along which the nerve impulse passes during the implementation of the reflex is called.

The concept of “reflex” was introduced by Sechenov, he believed that “reflexes form the basis of the nervous activity of humans and animals.” Pavlov divided reflexes into conditioned and unconditioned.

Comparison of conditioned and unconditioned reflexes

Development of a conditioned reflex

Conditional (indifferent) the stimulus must precede unconditional(causing an unconditioned reflex). For example: a lamp is lit, after 10 seconds the dog is given meat.

Inhibition of conditioned reflexes

Conditional (non-reinforcement): the lamp lights up, but the dog is not given meat. Gradually, salivation when the lamp is turned on stops (the conditioned reflex fades).

Unconditional: During the action of a conditioned stimulus, a powerful unconditioned stimulus arises. For example, when the lamp is turned on, the bell rings loudly. No saliva is produced.

Choose one, the most correct option. The centers of conditioned reflexes, in contrast to unconditioned ones, are located in humans in
1) cerebral cortex
2) medulla oblongata
3) cerebellum
4) midbrain

Answer

Choose one, the most correct option. Salivation in a person at the sight of a lemon is a reflex
1) conditional
2) unconditional
3) protective
4) approximate

Answer

Choose three options. The peculiarity of unconditioned reflexes is that they




5) are congenital
6) are not inherited

Answer

Choose three correct answers out of six and write down the numbers under which they are indicated. Unconditioned reflexes that ensure life activity human body,
1) are developed in the process of individual development
2) formed in the process of historical development
3) are present in all individuals of the species
4) strictly individual
5) formed under relatively constant environmental conditions
6) are not congenital

Answer

Choose three correct answers out of six and write down the numbers under which they are indicated. The peculiarity of unconditioned reflexes is that they
1) arise as a result of repeated repetition
2) are a characteristic characteristic of an individual individual of the species
3) are genetically programmed
4) are characteristic of all individuals of the species
5) are congenital
6) build skills

Answer

Choose one, the most correct option. What are the features of spinal reflexes in humans and mammals?
1) acquired during life
2) are inherited
3) are different in different individuals
4) allow the organism to survive in changing environmental conditions

Answer

Choose one, the most correct option. The extinction of a conditioned reflex when it is not reinforced by an unconditioned stimulus is
1) unconditional inhibition
2) conditioned inhibition
3) rational action
4) conscious action

Answer

Choose one, the most correct option. Conditioned reflexes of humans and animals provide
1) adaptation of the body to constant environmental conditions
2) adaptation of the body to the changing external world
3) development of new motor skills by organisms
4) discrimination by animals of the trainer’s commands

Answer

Choose one, the most correct option. A baby's reaction to a bottle of milk is a reflex that
1) inherited
2) is formed without the participation of the cerebral cortex
3) acquired during life
4) persists throughout life

Answer

Choose one, the most correct option. When developing a conditioned reflex, the conditioned stimulus must
1) act 2 hours after unconditional
2) come immediately after the unconditional
3) precede the unconditional
4) gradually weaken

Answer

1. Establish a correspondence between the meaning of the reflex and its type: 1) unconditional, 2) conditional. Write numbers 1 and 2 in the correct order.
A) provides instinctive behavior
B) ensures the adaptation of the organism to the environmental conditions in which many generations of this species lived
C) allows you to gain new experience
D) determines the behavior of the organism in changed conditions

Answer

2. Establish a correspondence between the types of reflexes and their characteristics: 1) conditional, 2) unconditional. Write numbers 1 and 2 in the order corresponding to the letters.
A) are congenital
B) adaptation to new emerging factors
C) reflex arcs are formed in the process of life
D) are the same in all representatives of the same species
D) are the basis of learning
E) are constant, practically do not fade during life

Answer

Choose one, the most correct option. Conditioned (internal) inhibition
1) depends on the type of higher nervous activity
2) appears when a stronger stimulus occurs
3) causes the formation of unconditioned reflexes
4) occurs when the conditioned reflex fades

Answer

Choose one, the most correct option. The basis of nervous activity in humans and animals is
1) thinking
2) instinct
3) excitement
4) reflex

Answer

1. Establish a correspondence between the examples and types of reflexes: 1) unconditional, 2) conditional. Write numbers 1 and 2 in the correct order.
A) withdrawing a hand from the fire of a burning match
B) a child crying at the sight of a man in a white coat
C) a five-year-old child reaching out to the sweets he saw
D) swallowing pieces of cake after chewing them
D) salivation at the sight of a beautifully set table
E) downhill skiing

Answer

2. Establish a correspondence between the examples and the types of reflexes that they illustrate: 1) unconditional, 2) conditioned. Write numbers 1 and 2 in the order corresponding to the letters.
A) sucking movements of the child in response to touching his lips
B) constriction of the pupil illuminated by the bright sun
C) performing hygiene procedures before bed
D) sneezing when dust enters the nasal cavity
D) secretion of saliva to the clink of dishes when setting the table
E) roller skating

Answer

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