Sensation is a reflection of the properties of objects of the objective world, arising from their direct impact on the sense organs, this is, firstly, the initial moment of the sensorimotor reaction; secondly, the result of conscious activity.

The emergence of sensation is directly related to the work of human receptors. A receptor is an organ specially adapted for the reception of stimuli; it is more easily irritated than other organs or nerve fibers; its sensitivity is especially high. In addition, each receptor is specialized in relation to a particular stimulus.

In the process of biological evolution, the sense organs themselves were formed in the real relationship of the organism with the environment, under the influence of the outside world. The impact of the outside world forms the receptors themselves. Receptors are, as it were, anatomically fixed in the structure of the nervous system, imprints of the effects of irritation processes.

In sensation, absolute and differential thresholds are distinguished. Not every stimulus causes a sensation, but only one whose intensity has overcome the threshold of sensation. This minimum stimulus intensity at which a sensation occurs is called the lower absolute threshold. Along with the lower, there is also an upper absolute threshold, i.e. the maximum intensity possible to experience a given quality.

The thresholds of sensitivity are significantly shifted depending on the attitude of a person to the task that he solves.

For the sensitivity of an organ, its physiological state is also important. The significance of physiological moments is manifested primarily in the phenomena of adaptation, in the adaptation of an organ to a long-acting stimulus. The phenomenon of contrast is also associated with adaptation, which is associated with a change in sensitivity under the influence of a previous (or accompanying) stimulus.

Differentiation and specialization of receptors does not exclude their interaction, which is expressed in the effect that stimulation of one receptor has on the thresholds of another.

Classification of sensations

organic sensations. Organic sensations include sensations of hunger, thirst, sensations coming from the cardiovascular, respiratory and reproductive systems of the body, and all sensations associated with the state of the human body.

All organic sensations have a number of common features:

They are usually associated with organic needs, which are usually first reflected in consciousness through organic sensations.

All organic sensations are more or less brightly colored.

Organic sensations, reflecting needs, are usually associated with motor impulses and are interconnected in a psychomotor unity.

Static sensations. These are sensations associated with indications of the position of our body in space, its posture, passive and active movements of the body. The central organ that regulates the balance of the body in space is the vestibular apparatus.

kinesthetic sensations. Sensations of movement of various parts of the body are caused by excitations coming from proprioreceptors located in the joints, ligaments and muscles. Through kinesthetic sensations, a person can determine the position and movement of their body parts. Impulses entering the central nervous system from proprioceptors due to changes that occur during movement in the muscles cause reflex reactions and play a significant role in muscle tone and coordination of movements.

Skin sensitivity. Skin sensitivity is subdivided by the classical physiology of the sense organs into 4 types. These are the receptions of pain, heat, cold and touch (pressure). It is assumed that each of these types of sensitivity also has specific receptors.

Touch. Touch includes sensations of touch and pressure in unity with kinesthetic, muscular-articular sensations. The proprioceptive components of touch come from receptors located in muscles, ligaments, and articular bags. When moving, they are irritated by a change in voltage.

Olfactory sensations. Olfactory sensations arise when molecules of various substances enter the nasal cavity together with the inhaled air and are transmitted to the central nervous system through the olfactory receptor.

Taste sensations. Taste sensations, like olfactory sensations, are due to the chemical properties of substances. Taste sensations play an important role in adjusting the emotional state of a person, their role is determined by the state of the body's need for food. Arise through the taste receptor, the peripheral part of which is located in the oral cavity.

Auditory sensations. Auditory sensations are a reflection of sound waves affecting the auditory receptor, which are generated by the sounding body and represent a variable condensation and rarefaction of air.

visual sensations. Visual sensations are caused by exposure to the visual analyzer of a light wave, which differ in length and frequency of oscillations.

As you know, the realization of personal potential is carried out in the process of life. It, in turn, is possible due to the person's knowledge of the surrounding conditions. Ensuring the interaction of the individual with the outside world is determined by attitudes and motives. Meanwhile, any mental phenomenon is a reflection of reality and is a link in the regulation system. The determining element in the functioning of the latter is feeling. Concept, physiological basis feelings, in turn, are associated with thinking and logical knowledge. Words and language as a whole play a significant role in this, they realize the function of generalization.

Inverse relationship

The physiological foundations of sensation, in short, are the basis on which human sensory experience is formed. His data, memory representations determine logical thinking. All, what is the physiological basis of sensations, acts as a link between a person and the outside world. Feelings allow you to know the world. Let us next consider how physiological basis of sensations in psychology (briefly).

Sensory organization

It represents the level of development of certain systems of sensitivity, the possibility of their combination. Sensory structures are called They act like. Sensory structures can be called receivers. Sensations enter them and are transformed into perceptions. Any receiver has a certain sensitivity. If we turn to representatives of the fauna, it can be noted that the physiological basis of their sensations is the activity of a certain type of sensors. This, in turn, acts as a generic sign of animals. For example, bats are sensitive to short ultrasonic pulses, dogs have an excellent sense of smell. If you touch physiological basis of sensations and perceptions human, it should be said that the sensory system has existed since the first days of life. However, its development will depend on the efforts and desires of the individual.

The concept of sensation: the physiological basis of the concept (briefly)

Before considering the mechanism of functioning of the elements of the sensory system, it is necessary to determine the terminology. Sensation is a manifestation of a general biological property - sensitivity. It is inherent in living matter. Through sensations, a person interacts with the external and his inner world. Due to them, information about ongoing phenomena enters the brain. All, what is the physiological basis of sensations, allows you to get different information about objects. For example, about their taste, color, smell, movement, sound. Sensors transmit information about the state of internal organs to the brain. From the sensations that arise, a picture of perception is formed. The physiological basis of the sensation process allows for primary data processing. They, in turn, act as a basis for more complex operations, for example, such processes as thinking, memory, perception, representation.

Data processing

It is carried out by the brain. The result of data processing is the development of a response or strategy. It can be aimed, for example, at increasing the tone, greater concentration of attention on the current operation, setting for accelerated inclusion in the cognitive process. The number of options available, as well as the quality of the choice of a particular reaction, depends on various factors. In particular, the individual characteristics of the individual, the strategies for interacting with others, the level of organization and development of higher nervous functions, and so on will be important.

Analyzers

The physiological basis of sensations is formed due to the functioning of special nervous apparatus. They include three components. The analyzer distinguishes between:

1. Receptor. It acts as a receiver. The receptor converts the external energy into a nerve operation.
2. Central department. It is represented by afferent or sensory nerves.
3. Cortical sections. In them, nerve impulses are processed.

Certain areas of the cortical regions correspond to specific receptors. Each sense organ has its own specialization. It depends not only on the structural features of the receptors. Equally important is the specialization of neurons, which are included in the central apparatus. They receive signals passing through the peripheral senses. It should be noted that the analyzer is not a passive receiver of sensations. It has the ability to reflex restructuring under the influence of stimuli.

Information properties

Allows you to describe the data coming through the sensors. Any information can be characterized by its inherent properties. The key ones include duration, intensity, spatial localization, quality. For example, the latter is a specific feature of a particular sensation, in which it differs from the rest. Quality varies within a certain modality. So, in the visual spectrum, such properties as brightness, color tone, saturation are distinguished. Auditory sensations have such qualities as pitch, timbre, loudness. With tactile contact, the brain receives information about the hardness, roughness of the object, and so on.

Features of differentiation

What can be physiological basis of sensations? Classification of sensations can be carried out on different grounds. The simplest is differentiation according to the modality of the stimulus. Accordingly, on this basis, one can distinguish and . Modality is a qualitative characteristic. It reflects the specificity of sensations as the simplest mental signals. Differentiation is carried out depending on the location of the receptors. On this basis, three groups of sensations are distinguished. The first includes those associated with surface receptors: skin, olfactory, gustatory, auditory, visual. The sensations that arise in them are called exteroceptive. The second group includes those associated with sensors located in the internal organs. These sensations are called interoreceptive. The third group includes those that are associated with receptors located on the muscles, tendons and ligaments. These are motor and static sensations - proprioceptive. Differentiation is also carried out according to the modality of the sensor. On this basis, sensations are distinguished contact (gustatory, tactile) and distant (auditory, visual).

Types

Physiological basis of sensations- complex elements of a single sensory system. These links allow you to recognize different properties of one object at the same time. This is due to the fact that they react to certain stimuli. Each receptor has its own agent. In accordance with this, there are such as:

1. Visual. They arise under the influence of light rays on the retina.
2. Auditory. These sensations are caused by speech, music or noise waves.
3. Vibrating. Such sensations arise due to the ability to capture the vibrations of the environment. Such sensitivity is poorly developed in humans.
4. Olfactory. They allow you to capture odors.
5. Tactile.
6. Skin.
7. Taste.
8. Painful.
9. Temperature.

The emotional coloring of pain is especially strong. They are visible and audible to others. Temperature sensitivity varies in different parts of the body. In some cases, a person may experience pseudo-sensations. They are expressed in the form of hallucinations and appear in the absence of an irritant.

Vision

The eye acts as the perceiving apparatus. This sense organ has a rather complex structure. Waves of light are reflected from objects, refracted as they pass through the lens, and are fixed on the retina. The eye is considered a distant receptor, since it gives an idea of ​​objects that are at a distance from a person. Reflection of space is provided due to the parity of the analyzer, changing the size of the image on the retina when approaching / moving away from / from the object, the ability to bring and dilute the eyes. The retina contains several tens of thousands of nerve endings. Under the influence of a wave of light, they are irritated. Nerve endings are distinguished by function and form.

Hearing

Sensory endings that allow you to perceive sound are located in the inner ear, the cochlea with a membrane and hairs. The external organ collects vibrations. The middle ear directs them to the cochlea. The sensitive endings of the latter are irritated due to resonance - nerves of different thickness and length begin to move when a certain number of vibrations per second arrives. The received signals are sent to the brain. Sound has the following properties: strength, timbre, pitch, duration and tempo-rhythmic pattern. Phonemic is called hearing, which allows you to distinguish between speech. It depends on the environment and is formed during life. With a good knowledge of a foreign language, a new system of phonemic hearing is developed. It has an impact on writing skills. Similarly, speech develops. Less important for a person are rustles and noises, if they do not interfere with his activities. They can also evoke pleasant emotions. For example, many people like the sound of rain, the rustle of leaves. At the same time, such sounds can also signal danger. For example, the hiss of gas.

Vibration sensitivity

It is considered a type of auditory sensation. Vibration sensitivity reflects fluctuations in the environment. It is figuratively called contact hearing. Humans do not have special vibrational receptors. Scientists believe that such sensitivity is the oldest on the planet. At the same time, all tissues in the body can reflect fluctuations in the external and internal environment. Vibrational sensitivity in human life is subject to visual and auditory. Its practical importance increases in those areas of activity where fluctuations act as signals of malfunctions or danger. Deaf-blind and deaf people have increased vibration sensitivity. It compensates for the absence of other sensations.

Smell

It refers to distant sensations. Elements of substances penetrating into the nasal cavity act as irritants that cause olfactory sensitivity. They dissolve in liquid and act on the receptor. In many animals, smell is the primary sense. They navigate by smell when looking for food or escaping from danger. The human sense of smell has little to do with orienteering. This is due to the presence of hearing and vision. The instability and underdevelopment of olfactory sensitivity is also indicated by the absence in the vocabulary of words that accurately denote sensations and are not related to the subject itself. For example, they say "the smell of lilies of the valley." The sense of smell is related to taste. It helps to recognize the quality of food. In some cases, the sense of smell allows you to distinguish substances by chemical composition.

Taste

It refers to contact sensations. Taste sensitivity is caused by irritation of the receptors located on the tongue with the object. They allow you to identify sour, salty, sweet, bitter foods. The combination of these qualities forms a set of taste sensations. Primary data processing is carried out in papillae. Each of them has 50-150 receptor cells. They wear out fairly quickly when in contact with food, but have a recovery function. Sensory signals are sent to the gustatory cortex via the hindbrain and thalamus. Like olfactory sensations, these sensations increase appetite. Receptors, evaluating the quality of food, perform a protective function, which is very important for survival.

Leather

It contains several independent sensory structures:

1. Tactile.
2. Painful.
3. Temperature.

Skin sensitivity belongs to the group of contact sensations. The maximum number of sensory cells is found on the palms, lips and fingertips. Information is transmitted from receptors to the spinal cord due to their contact with motor neurons. This ensures the implementation of reflex actions. For example, a person pulls his hand away from the hot. Temperature sensitivity ensures the regulation of heat exchange between the external environment and the body. It is worth saying that the distribution of cold and thermal sensors is uneven. The back is more sensitive to low temperature, the chest is less. Pain occurs due to strong pressure on the surface of the body. Nerve endings are located deeper than tactile receptors. The latter, in turn, allow you to form an idea of ​​the qualities of the subject.

Kinesthetic Sensitivity

It includes sensations of movement and staticness of individual elements of the body. Receptors are located in tendons and muscles. Irritation is caused by contraction and stretching of the muscles. Many motor sensors are located on the lips, tongue, and fingers. This is due to the need for these parts of the body to perform subtle and precise movements. The work of the analyzer provides control and coordination of movement. The formation of speech kinesthesia occurs in infancy and preschool age.

vestibular sensitivity

Static or gravitational sensations allow a person to understand their position in space. The corresponding receptors are located in the vestibular apparatus in the inner ear. The sacs and canals convert signals about relative movement and gravity, then transmitting them to the cerebellum, as well as to the cortex in the temporal region. A sharp and frequent change in the position of the body relative to the ground can lead to dizziness.

Conclusion

The physiological basis is of particular practical importance. Its study makes it possible to determine the pathways for the penetration of signals from the outside, to distribute them among receptors, and to trace the course of primary information processing. The physiological basis of sensations in psychology is the key to understanding the properties of the human sensory system. The analysis allows you to identify the causes of certain deviations in sensitivity, to assess the degree of impact of certain stimuli on receptors. The obtained information is used in various scientific and industrial fields. Research results play a special role in medicine. The study of the properties of receptors and stimuli allows you to create new drugs, develop more effective tactics for the treatment of mental and other diseases.

The concept of sensation

Sensation is one of the simplest cognitive mental processes. The human body receives a variety of information about the state of the external and internal environment in the form of sensations with the help of the senses. Sensation is the very first connection of a person with the surrounding reality. The process of sensation arises as a result of the impact on the sense organs of various material factors, which are called stimuli, and the process of this impact itself is irritation.

Feelings arise on the basis of irritability. Sensation is a product of development in the phylogenesis of irritability. Irritability- the common property of all living bodies to come into a state of activity under the influence of external influences (pre-psychic level), i.e. directly affecting the life of the organism. At an early stage in the development of living things, the simplest organisms (for example, a ciliate shoe) do not need to distinguish between specific objects for their life activity - irritability is sufficient. At a more complex stage, when a living thing needs to determine any objects that it needs for life, and, consequently, the properties of this object as necessary for life, at this stage, irritability is transformed into sensitivity. Sensitivity- the ability to respond to neutral, indirect influences that do not affect the life of the organism (an example with a frog that reacts to a rustle). The totality of feelings creates elementary mental processes, processes of mental reflection.

Irritation causes excitation, which passes through the centripetal, or afferent, nerves to the cerebral cortex, where sensations arise. Thus, sensation is a sensory reflection of objective reality.

Feeling- the simplest mental process of reflecting a separate quality (property) of an object with the direct impact of stimuli on the perceiving part of the analyzer.

At this level, there is still no synthesis of sensations into a better reflection. This is the level of the most elementary reflection. Each stimulus has its own characteristics, depending on which it can be perceived by certain sense organs. Thanks to sensations, a person distinguishes objects and phenomena by color, smell, taste, smoothness, temperature, size, volume and other features. Sensations arise from direct contact with an object. So, for example, we learn about the taste of an apple when we try it. Or, for example, we can hear the sound of a mosquito flying or feel its bite. In this example, sound and bite are sensory stimuli. At the same time, attention should be paid to the fact that the process of sensation reflects in the mind only a sound or only a bite, in no way connecting these sensations with each other, and, consequently, with a mosquito. This is the process of reflecting the individual properties of the object.

Nevertheless, sensations are the main source of information for a person. On the basis of this information, the entire human psyche is built - consciousness, thinking, activity. At this level, there is a direct interaction of the subject with the material world. Those., Feelings underlie all human cognitive activity.

The physiological basis of sensations

The physiological basis of sensations is the activity of complex complexes of anatomical structures, called by I. P. Pavlov analyzers. Analyzer- anatomical and physiological apparatus for receiving influences from the external and internal environment and processing them into sensations. Each analyzer consists of three parts:

1) peripheral department, called a receptor (the receptor is the perceiving part of the analyzer, a specialized nerve ending, its main function is the transformation of external energy into a nervous process);

2) conducting nerve pathways(afferent department - transmits excitation to the central department; efferent department - a response is transmitted through it from the center to the periphery);

3) analyzer core- the cortical sections of the analyzer (they are also called the central sections of the analyzers), in which the processing of nerve impulses coming from the peripheral sections takes place. The cortical part of each analyzer includes an area that is a projection of the periphery (i.e., a projection of the sense organ) in the cerebral cortex, since certain areas of the cortex correspond to certain receptors.

sensations

(receptor)

Here there is a transformation of a certain type of energy into a nervous process.

Through afferent, or centripetal, pathways, excitation is transmitted to the central section of the analyzer

Analyzer- anatomical and physiological apparatus, specialized for receiving the effects of certain stimuli from the external and internal environment and processing them into sensations

The physiological basis of sensations is laid down in the work of special nervous structures, called analyzers by I. Pavlov. Analyzers are channels through which a person receives all the information about the world (both about the external environment and about his own, internal state).

Together, the analyzers form the human sensory system.

The beginning of sensation is given by the physical process of irritation, which occurs when signals from the external or internal environment act on the human senses: vision, smell, etc. Sensations are provided by the work of the brain. The brain is connected with the sense organs that react to "their" stimuli. In order for the brain to perceive these stimuli, they must be given to it in a certain form, namely in the form of electrical signals. The energy of stimuli of various nature (light, smell, etc.) must be converted into electrical energy. The task of translating signals of various modalities into an electrical form is solved by receptors.

A receptor is a specific neuron that receives physical signals from the external environment and signals from the internal state of a person. The work of the receptor is specialized. Each receptor works with “its own” signals: the visual receptor reacts to light stimuli, the auditory receptor to sound stimuli, and so on. But this is not a simple response. The brain requires information not only about the presence of a stimulus, but also about its characteristics (for example, on scales intense - weak, large - small, sweet - bitter, etc.). Therefore, the receptor must be able to encode these characteristics in order to transmit information about them to the brain. Such coding is implemented through the transformation of physical stimuli into electrical signals with parameters corresponding to the characteristics of the stimulus. So, for example: sensations of a pleasant voice timbre correspond to electrical signals of a sinusoidal shape; sensations of touching the hand - a successive series of rectangular electrical impulses (in this case, a light touch corresponds to a small number of impulses in a series, a strong pressure - a large number).

Encoded electrical signals of a certain form with the appropriate parameters along the nerve pathways (afferent nerves) enter the receptive zones of the cerebral cortex. Each receptor of one or another modality has its own receptive zone. The movement of signals is provided by the physiological process of excitation - the property of nerve cells (neurons) to respond to irritation. When excited, the cell moves from a state of physiological rest to activity. If the amplitude of excitation reaches a threshold value, then it spreads to neighboring parts of the nervous system. In the cerebral cortex, an electrical signal causes the simplest emotional experiences of sensations. The results of experiences in the form of a spreading excitation through the efferent nerves come to the periphery of the body (to the muscles, glands).

1.6.2 Analyzers

Functional diagram of the analyzer

The analyzer is not a passive element. His work can be rebuilt under the changing influence of stimuli. In other words, the nature of the analyzer is reflexive, i.e. reflects real changes in the environment. Naturally, the nature of sensations is also reflexive. Sensations are always associated with motor components. This occurs either in the form of a vegetative reaction (narrowing of the pupils, blood vessels, etc.), or in the form of a muscular reaction (twitching of the hand, turning of the eyes, tension of the muscles of the lips, etc.).

Indeed, sensation is not limited to a simple reflection of reality in the human brain. An obligatory element of sensation (without which, in fact, it is impossible) is the body's response. This reaction may take the form of a movement or an internal process, such as a healing one. It has long been known, for example, that the singing of birds, the sound of the surf balance the nervous system; sounds of music such as "hard rock" and "rock music" often cause aggressive nervous system excitement in fans, as well as acute stomach cramps.

The body reacts to the sensations of smells. The Japanese firm "Shieydo" successfully uses "smell therapy" to increase the stress resistance of its employees. The synthesis of aromas is used in production and at home. The result - errors in the work decreased by more than 50%.

The body reacts no less sharply to a prolonged or complete absence of stimuli (sensory hunger or sensory deprivation). Sensory hunger (sensory deprivation) is a phenomenon associated with a sharp decrease in the "range" of sensations (or complete loss) experienced by a person in situations of physical and psychological isolation.

The results of sensory hunger can be devastating to the human psyche. Having lost his hearing, Ludwig van Beethoven experienced a life drama: he shunned people, suffered deeply from loneliness: “It is not given to me to find inspiration in the company of people, in subtle conversation, in mutual frankness. Alone, completely alone! .. I must live like an outcast.

So that the operator of tracking aerial targets on the radar screen in the mode of a long and continuous review of "empty" space does not dull his vigilance, does not decrease his efficiency, a false target mark from a special imitator is "thrown" on the screen from time to time.

The physiological basis of sensations is the work of analyzers. The physiological apparatus by which sensation arises is the analyzer. The analyzer (sensory organ) is an anatomical and physiological apparatus located on the periphery of the body or in internal organs; it receives irritation from the external and internal environment. Each such device connects the brain with the outside world and provides a variety of information. In order for a person to have normal sensations, a healthy state of all three sections of the analyzer is necessary: ​​a conductive receptor; neural pathway; cortical part.

1. 3. 2. 4. 1. Neuroconductive pathways 2. Cerebral cortex 3. Analyzer sections in c.g.m. 4. Taste buds

Exteroreceptive Interoreceptive Proprioceptive 1. Visual 2. Olfactory 3. Taste 4. Auditory 5. Temperature 6. Tactile 1. Feeling pain 2. Feeling balance 3. Feeling acceleration

The process of irritation consists in the appearance of an action potential in the nerve tissues and its penetration to the sensitive nerve fiber. Stimuli cause excitation in the nervous tissue. A specialized part of the analyzer, through which a certain type of energy is transformed into a process of nervous excitation, is called a receptor.

Physical process stimulus Sensation organ Physiological process excitation Pathways Psychological process Center in the cerebral cortex

The quality of sensation is a property that characterizes the basic information displayed by this sensation, which distinguishes it from other sensations. One can also say this: the quality of sensation is a property that cannot be measured with the help of numbers, compared with some kind of numerical scale. For a visual sensation, the quality can be the color of the perceived object. For taste or smell, the chemical characteristic of an object: sweet or sour, bitter or salty, floral smell, almond smell, hydrogen sulfide smell, etc.

It is important to understand that the intensity of sensation depends on two factors that can be designated as objective and subjective: - the strength of the acting stimulus (its physical characteristics), - the functional state of the receptor, which is affected by this stimulus. The more significant the physical parameters of the stimulus, the more intense the sensation. For example, the higher the amplitude of a sound wave, the louder the sound appears to us. And the higher the sensitivity of the receptor, the more intense the sensation.

A person exists in space, and the stimuli that act on the sense organs are also located at certain points in space. Therefore, it is important not only to perceive the sensation, but also to spatially localize it. The analysis carried out by the receptors gives us information about the localization of the stimulus in space, that is, we can tell where the light comes from, the heat comes from, or which part of the body is affected by the stimulus.

The duration of the sensation - it indicates the time of existence of the sensation that has arisen. The duration of sensation is also influenced by objective and subjective factors. The main factor, of course, is objective - the longer the action of the stimulus, the longer the sensation. However, the duration of sensation is also affected by the functional state of the sense organ, and some of its inertness. After the beginning of the impact of the stimulus on the sense organ, the sensation does not occur immediately, but after some time. The latent period of different types of sensations is not the same. For tactile sensations - 130 ms, for pain - 370 ms, for taste - only 50 ms. The sensation does not arise simultaneously with the beginning of the action of the stimulus and does not disappear simultaneously with the termination of its action.

General laws of sensations: absolute threshold The absolute threshold of sensation (lower threshold of sensations) is those minimum physical characteristics of the stimulus, starting from which a sensation arises. Stimuli, the strength of which lies below the absolute threshold of sensation, do not give sensations. By the way, this does not mean at all that they do not have any effect on the body.

General patterns of sensations: The upper threshold of sensations is a high stimulus, at which it ceases to be perceived adequately. Another name for the upper absolute threshold is the pain threshold, because when we overcome it, we experience pain: pain in the eyes when the light is too bright, pain in the ears when the sound is too loud, etc.

General laws of sensations: relative threshold Relative threshold (distinction threshold) is the minimum change in the intensity of the stimulus that causes changes in sensations.

Adaptation, or adaptation, is a change in sensitivity under the influence of a constantly acting stimulus, which manifests itself in a decrease or increase in thresholds. Strong stimulus - weak sensitivity Weak stimulus - high sensitivity ADAPTATION RULE: When moving from strong to weak stimuli, sensitivity increases, from weak to strong decreases (stimulus and sensitivity are in inverse proportion)

The interaction of sensations is a change in the sensitivity of one analyzer system under the influence of the activity of another system. The general pattern of the interaction of sensations is as follows: weak stimuli of one analyzer system increase the sensitivity of another system, strong ones reduce it. For example, weak taste sensations (sour) increase visual sensitivity. Weak sound stimuli increase the color sensitivity of the visual analyzer. At the same time, there is a sharp deterioration in the various sensitivity of the eye due to the strong noise of an aircraft engine. All our analyzer systems are capable of influencing each other to a greater or lesser extent.

An increase in sensitivity as a result of the interaction of analyzers, as well as systematic exercises, is called sensitization. The possibilities for training the sense organs and their improvement are very great.

The phenomenon of sensitization of the sense organs is observed in people who have been engaged in certain types of professional activities for a long time. A high level of perfection is achieved by olfactory and gustatory sensations in tasters of tea, cheese, and wine. Tasters can accurately indicate not only what grape variety the wine is made from, but also the place where the grapes are grown. Painting makes special demands on the perception of form, proportions and color relationships when depicting objects. Experiments show that the artist's eye is extremely sensitive to the assessment of proportions. Our sensations develop under the influence of the conditions of life and the requirements of practical activity.

- compensatory sensitization due to the need to compensate for sensory defects (blindness, deafness); Loss of sight or hearing is compensated by the development of other types of sensitivity. There are cases when people who have lost their sight have developed skin sensitivity, they have well-developed tactile sensations, vibration sensitivity. A person suffering from deafness, holding his hand on the interlocutor's throat, can understand who is talking about what, and also, taking a newspaper in his hands, knows whether he has read it or not. ANDREA BACELLI RAY CHARLES DIANA GURTSKAYA

Desensitization - a decrease in the sensitivity of analyzers in the process of interaction of sensations. The interaction of sensations in some cases leads to sensitization, to an increase in sensitivity, and in other cases to its decrease, i.e., to desensitization. Strong excitation of some analyzers always lowers the sensitivity of other analyzers. So, the increased noise level in "loud shops" lowers visual sensitivity.

The contrast of sensations is a change in the intensity and quality of sensations under the influence of a preliminary or accompanying stimulus. In the case of the simultaneous action of two stimuli, a simultaneous contrast occurs. Such a contrast can be traced in visual sensations. The same figure appears lighter on a black background, darker on a white one. A green object on a red background seems more saturated. The phenomenon of consistent contrast is also well known. After a cold, a weak warm stimulus seems hot. The sensation of sour increases the sensitivity to sweet. If you fix a bright spot with your eye for 20-40 seconds, and then close your eyes or look at a low-light surface, then within a few seconds you can feel a fairly clear dark spot. This will be a consistent visual image.

Synesthesia (joint sensation) is the ability of a stimulus addressed to a particular sense organ to simultaneously cause a sensation in another sense organ (the sight of a yellow lemon causes a sour sensation). Engineer K. L. Leontiev, using the phenomenon of synesthesia, developed an apparatus that transforms sound signals into color ones. Based on this invention, colored music was created.

The complete deprivation of a person of sensory impressions, carried out for experimental purposes (for example, by immersion in water in special equipment). In response to the insufficiency of sensations, the processes of imagination are activated, which in a certain way affect the figurative memory. Bright eidetic representations arise, projected outward, which are evaluated as protective (compensatory) reactions. As the time spent in S.'s conditions at the stage of unstable mental activity increases, people develop emotional lability with a shift towards low mood (lethargy, depression, apathy), which are briefly replaced by euphoria and irritability. There are memory impairments that are directly dependent on the cyclical nature of emotional states. The rhythm of sleep and wakefulness is disturbed, hypnotic states develop with the appearance of hypnotic representations, which, unlike the sleepy states that occur under normal conditions, drag on for a relatively long time, are projected outward and are accompanied by the illusion of involuntariness. The more severe the conditions of S. d., the faster the processes of thinking are disrupted, which manifests itself in the inability to concentrate on anything, consistently think over problems, appear