Types of sensations are their characteristics. General characteristics of sensations

So, sensation is a mental reflection of the isolated properties of objects of the objective world, arising from their direct impact on the senses.

The emergence of sensations is associated with special physiological processes involved in the reception and primary transformation of the effects of certain stimuli from the external and internal environment of the body. These devices are called analyzers(I.P. Pavlov). Each analyzer consists of three parts: first, the peripheral section (receptor), where the recoding of physical effects into nerve impulses takes place; secondly, afferent (from lat. afferentis - bringing) nerve pathways, along which information encoded in the form of nerve impulses is transmitted to the central nervous system (at the exit

7.1. Feeling

our animals and humans - to the brain), and, thirdly, the analyzer center - a special section of the cerebral cortex. As a result of the processing of the information received in the cortical section of the analyzer, sensations arise. The reverse signal, which implements the body's response to a stimulus, passes through the efferent (from Latin efterentis - outgoing) nerve pathways.

Living beings differ in the stimuli to which they respond, and, accordingly, in the sensations that they experience. There is evidence that birds navigate during long-distance flights along the Earth's magnetic field and therefore must have some kind of “magnetic” sensation that is inexplicable to humans. Sharks are sensitive to electrical discharges coming from the scales of fish. Bats have a special ultrasonic analyzer with which they recognize obstacles encountered in their path. Insects see in the part of the color spectrum inaccessible to us. Human hearing fixes a range of 15-20,000 Hz, while a dog can distinguish sounds of a higher frequency. This effect is based on the well-known circus act of "transmitting orders at a distance" from the trainer to the animal. The dog is trained to respond in a certain way to a whistle at about 35,000 Hz. Spectators can't hear the cues (it's easy enough to produce these kinds of sounds with a slightly modified whistle) and it appears to them that the dog is performing magic tricks by reading the owner's mind. Probably, under certain conditions, a person can also develop sensitivity to stimuli that are usually beyond the ability of sensory systems to work. An example is the experiment on the formation of "skin vision", conducted by A.N. Leontiev (see 7.1.4).

Various analyzers have an unequal projection in the cerebral cortex. Experimentally, maps were obtained that schematically show the location and size of the area of ​​the cortex, which provides an analysis of sensations coming from different areas of the body. One such map is shown in Fig. 40. Note that different types of animals have significantly different "maps".

So, in humans, the maximum area of ​​the cerebral cortex is occupied by the projection zones of the mouth, eyes and hands, which is determined by the leading role of vision, speech activity (it requires developed sensory sensitivity of the lips and tongue) and fine hand movements for social life. In an animal for which another type of sen-

The presence of highly specific analyzers, each of which is susceptible to only one particular type of stimulation, raises the problem of the relationship between the properties of sensations and the properties of objects in the external world. In other words, it is necessary to understand how accurately we can judge the real properties of stimuli from our feelings?

I. Müller (1801-1858) put forward the hypothesis of "specific energies of the sense organs". The essence of this hypothesis is that sensations do not reflect the real properties of the stimulus, but only signal the state of our analyzers. “What our sensations give us reflects, expresses the nature and state of our sense organs, nerves, and not the nature of what causes these sensations,” Muller wrote. He illustrated his idea with simple examples: if you hit the eyeball, a person will feel how “sparks fell from the eyes”, i.e. will receive a subjective visual sensation. Similarly, if you lick a strip of metal through which a weak electric current is passed, you get a sensation of a sour taste. One gets the impression that sensations are pure subjectivity, only incidentally connected with the objective world. The position of I. Müller at one time had a great influence on the interpretation of the phenomena of sensation. However, evolutionary reasoning leads us to the conclusion that we are dealing with a pseudo-problem.

7.1. Feeling

Even if in some cases we feel the world is not the way it is, in fact, our sensations as a whole are adequate to the world, since they allow us to effectively navigate in the environment. A deeper comprehension of the world is provided by another mental function - thinking, which consists in a generalized and mediated cognition of reality (see Chapter 9).

The second question that arises when discussing the topic of sensation is the question of the "immediacy" of the action of the stimulus. Indeed, we not only get sensations from stimuli that are in direct contact with the surface of our body (we touch, taste and smell), but we also see and hear what is at a considerable distance from us. Ancient thinkers solved this problem by assuming that objects "emit" the thinnest ethereal copies from themselves, which freely penetrate into the eyes, ears, etc. At a new round of development, science, in essence, has returned to a similar understanding, having found physical carriers of "distant" stimuli that make them "close". For vision, such a stimulus will be light, for hearing - air vibrations, for smell - the smallest particles of matter suspended in a neutral medium. According to Ch. Sherrington, sensations are usually divided into contact(the stimulus itself acts on the perceiving organ, and an intermediary delivering information is not required) and distant(i.e., a special “agent” is needed to bring information to the touch surface). Contact sensations are gustatory, olfactory, skin, kinesthetic (sensations of the position of individual parts of the body) and organic (hunger, thirst, etc.), distant - auditory and visual sensations.

However, there are other prerequisites for dividing sensations into distant and contact ones. They lie in the anatomical features of the structure of the corresponding sense organs. Obviously, contact sensations are phylogenetically older than distant sensations. The receptors of contact analyzers do not generally constitute integral sense organs. For example, tactile sensitivity is provided by isolated cells - skin receptors (the so-called Paccini's body, Meissner's body). The former respond to pressure, the latter to vibration. Distant analyzers, on the other hand, are complex ensembles that include both the receptors themselves, concentrated in a certain area of ​​the body, and additional “devices” that ensure maximum sensing efficiency. As A.N. Leontiev, at a certain stage of evolution, these ensembles acquire their own engine -

Chapter 7. Cognitive processes. Feeling and Perception

nym apparatus, they acquire motor capabilities that are quite autonomous from the rest of the body (propriomotor apparatus). The eye, for example, has oculomotor muscles, ciliary muscles, and so on. Thus, the impact on the distant sense organs implies a higher counter activity of the subject. No wonder A. Schopenhauer compared vision with feeling: “Vision can be regarded as an imperfect, but far-reaching touch that uses rays of light as long tentacles,” he wrote in his work “The World as Will and Representation.” Such an emancipation of distant sense organs can no doubt be regarded as an evolutionary breakthrough in the formation of sensory systems. Unlike contacts, they do not react to an already existing situation, but actively forestall it (P.K. Anokhin).

In addition to the division into contact and distant, C. Sherrington also proposed to classify sensations according to the location of their corresponding receptors (according to receptive fields). In this case, they differ interoreceptive sensations (from receptors located in the internal organs), proprioceptive(from receptors located in muscles, ligaments and tendons) and exteroceptive(from receptors located on the outer surface of the body). In general, the classification of sensations is presented in Table. 13.

Properties of sensations

One sensation may not be similar to another, even if they belong to the same modality (sight, hearing, etc.). The individual characteristics of each sensation are determined by the concept of "properties of sensations".

Each sensation can be characterized in its properties. Properties of sensations can be not only specific to a given modality, but also common to all types of sensations. The main properties of sensations, the most commonly used:

Quality,

Intensity,

duration,

spatial localization,

absolute threshold,

Relative threshold.

Quality of feeling

Characteristics of not only sensations, but in general all characteristics can be divided into qualitative and quantitative. For example, the title of a book or its author are qualitative characteristics; the weight of a book or its length are quantitative. The quality of sensation is a property that characterizes the basic information displayed by a given 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.

Sometimes the quality of sensation is understood as its modality (auditory sensation, visual or otherwise). This also makes sense, because often in a practical or theoretical sense one has to talk about sensations in general. For example, during the experiment, a psychologist can ask the subject a general question: "Tell me about your feelings during ..." And then the modality will be one of the main properties of the described sensations.

Feeling intensity

Perhaps the main quantitative characteristic of sensation is its intensity. In fact, it is of great importance for us whether we listen to quiet music or loud, it is light in the room or we can hardly see our hands.

It is important to understand that the intensity of sensation depends on two factors, which can be described as objective and subjective:

The strength of the acting stimulus (its physical characteristics),

The functional state of the receptor on which the stimulus acts.

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. For example, being in a dark room after a long stay and going out into a moderately lit room, you can "go blind" from bright light.

Duration of sensation

The duration of sensation is another important characteristic of sensation. It, as the name implies, denotes the time of existence of the sensation that has arisen. Paradoxically, but 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.

Suppose the intensity of some stimulus first gradually increases, then gradually decreases. For example, it can be a sound signal - from zero strength it grows to a clearly audible one, and then decreases again to zero strength. We do not hear a very weak signal - it is below the threshold of our perception. Therefore, in this example, the duration of the sensation will be less than the objective duration of the signal. At the same time, if our hearing had previously perceived strong sounds for a long period and did not have time to “depart” yet, then the duration of the sensation of a weak signal will be even less, because the perception threshold is high.

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. This inertia of sensations is manifested in the so-called aftereffect. The visual sensation, as you know, has some inertia and does not disappear immediately after the cessation of the action of the stimulus that caused it. The trace from the stimulus remains in the form of a consistent image.

Spatial localization of 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.

Absolute threshold of sensation

The absolute threshold of sensation 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. G. V. Gershuni's studies have shown that sound stimuli below the threshold of sensation can cause a change in the electrical activity of the brain and even dilation of the pupil. The zone of influence of irritants that do not cause sensations was called by G.V. Gershuni "subsensory area".

There is not only a lower absolute threshold, but also the so-called upper one - the value of the 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. However, there are some physical characteristics of stimuli that are not related to the intensity of exposure. Such, for example, is the frequency of sound. We do not perceive either very low frequencies or very high ones: the approximate range is from 20 to 20,000 Hz. However, ultrasound does not cause us pain.

Relative threshold of sensation

The relative threshold of sensation is also an important characteristic. Can we distinguish between the weight of a pood weight and a balloon? Can we tell the weight of two sticks of sausage that look the same in the store? It is often more important to evaluate not an absolute characteristic of a sensation, but just a relative one. This kind of sensitivity is called relative, or difference.

It is used both to compare two different sensations, and to determine changes in one sensation. Suppose we heard a musician play two notes on his instrument. Were the pitches of these notes the same? or different? Was one sound louder than the other? or was not?

The relative sensation threshold is the minimum difference in the physical characteristics of the sensation that will be noticeable. Interestingly, for all types of sensation there is a general pattern: the relative threshold of sensation is proportional to the intensity of sensation. For example, if you need to add three grams (no less) to a load of 100 grams (no less) to feel the difference, then you need to add six grams to a load of 200 grams for the same purpose.

Psychology and esotericism

Feel. The physiological basis of sensation. The physiological basis of sensation is a nervous process that occurs when a stimulus acts on an analyzer that is adequate to it. kinesthetic sensations signal about movements, a sense of balance, static sensations.

10. Feelings. general characteristics

Reader in general psychology: the subject of knowledge, Reader. Psychology of sensations and perceptions, S.L. Rubinstein Fundamentals of General Psychology

The mental processes by which images of the environment are formed, as well as images of the organism itself and its internal environment, are calledcognitive mental processes. It is cognitive mental processes that provide a person with knowledge about the world around him and about himself.

Feeling this is the simplest cognitive mental process, which consists in reflecting the individual properties of objects and phenomena of the material world, as well as the internal states of the body with the direct impact of stimuli on the corresponding receptors.

The physiological basis of sensation. The sensation arises as a reaction of the nervous system to a particular stimulus and has a reflex character.The physiological basis of sensation is a nervous process that occurs when a stimulus acts on an analyzer adequate to it.Receptor (periphery) -> afferent and efferent nerves -> subcortex and cortex (processing of nerve impulses).The analyzer is the initial and most important part of the entire path of nervous processes, or the reflex arc.(discovered by Sechenov). The reflex ring consists of a receptor, pathways, a central part, and an effector. The interconnection of the elements of the reflex ring provides the basis for the orientation of a complex organism in the surrounding world, the activity of the organism, depending on the conditions of its existence.The sense organ is both a receptor and an effector.

Classification of sensations.

Currently, there are two main types of classification of sensations: genetic and systematic.

Systematic classification of sensations (Sherrington) - according to the classification of receptors:

1. Distant (sight, hearing, smell) and contact (tactile, touch, taste)exteroreceptorslocated on the surface of the body and responding to influences from the external environment; Available environmental conditions

2. interoreceptorsresponding to changes in internal organs. Knowledge of the state of the internal environment

3. proprioreceptorsembedded in muscles and ligaments. - signal movements (kinesthetic sensations), a sense of balance (static sensations). knowledge about the relative position of body parts.

Limitation: not all sensations can be strictly attributed to one or another modality. There are sensations that occupy intermediate positions between traditional modalities. These are intermodal sensations (vibration).

Genetic classification of sensations.

Proposed by the English neurologist H. Head. He discernsepicritical and protopathic sensitivity.Epicritical Sensitivity:younger and more perfect sensitivity, allows you to accurately localize an object in space, it gives objective information about the phenomenon.Protopathic sensitivity:relatively more ancient and primitive, do not give an exact localization neither in external space, nor in the space of the body. They are characterized by constant affective coloration, theyrather reflect subjective statesthan objective processes.The ratio of protapotic and epicritical components in different types of sensitivity is different.Epicritical (desc): sight, hearing, touch, smell, taste. Protopathic vice versa.

Properties of sensations

1. Modality. In the analyzer, only one type of sensation can arise. The eye cannot perceive sound.

2. Quality ( a specific feature that distinguishes it from the rest). For example, the qualities of visual modality include brightness, saturation, and hue. The qualities of auditory sensations: pitch, loudness, timbre.

3. Intensity. The quantitative side of the stimulus, the degree of expression of this quality. The dependence of the intensity of sensation on the physical strength of the stimulus acting on the analyzer is mathematically expressed in the basic law of psychophysics, called

4. Spatial localization- this is a characteristic of sensation that allows you to determine the location of the acting stimulus. Color, light, sound correlates with the source

5. Temporal duration. The duration of the sensation. It is determined by the duration of exposure to the stimulus, its intensity, as well as the functional state of the analyzer. When an irritant is exposed to a sensory organ, sensation does not occur immediately, but after a certain period of time, called the "latent (hidden) period of sensation." When the action of the stimulus ceases, the sensation does not disappear simultaneously with it, but continues for some time in its absence. This effect is called "aftereffect (or inertia) of sensation."

Patterns of sensations.

1. Sensory adaptation.

Adaptation adaptation of sensitivity to a permanent stimulus, manifested in a decrease or increase in thresholds.Example: Adaptation to a long-acting odor, other odors continue to be felt as pungent as before.

Can be distinguished three varieties of this phenomenon.

1. prolonged action of the stimulus - the extinction of sensation. For example, during the day, a person may practically not feel the weight of clothing and its contact with the skin.

2. Adaptation as a dulling of sensation under the influence of a strong stimulus. For example, when a hand is immersed in cold water, the intensity of sensation caused by a temperature stimulus decreases.

1 and 2 - negative adaptation, as a result of which the sensitivity of the analyzers decreases.

3. increased sensitivity under the influence of a weak stimulus. In the visual analyzer, this is dark adaptation, example: visual sensitivity increases when a person enters a darkened space.

It has great biological significance, it helps to capture weak stimuli through the senses and protects the senses from excessive irritation in case of strong influences.

2. Interaction of sensations -change in the sensitivity of one analyzer system under the influence of the activity of another analyzer system.General pattern: weak stimuli in one analyzer system increase the sensitivity of another system, strong lowers it. For example, weak taste sensations (sour) increase visual sensitivity, strong noise reduces the sharpness of central vision, and weak increases. Mutual influences are noted between sound and visual sensations.

3. Sensitization increase sensitivity of the body to something as a result of the interaction of sensations and exercises(for example, hearing develops in children playing music). This is a variant of the interaction of sensations. It differs from adaptation: - Increases only in the direction of acuteness (adaptation can change in different directions), - Changes only from the well-being of the body, adaptation occurs only under the influence of the environment.

4. Synesthesia excitation by the arising sensations of one modality of sensations of another modality.Sound can be perceived in different colors. Synesthesia is seen in a wide variety of sensations. The most common visual-auditory synesthesia, when, under the influence of sound stimuli, the subject has visual images. There is no overlap between different people in these synesthesias, however, they are quite constant for each individual.

The phenomenon of synesthesia is another evidence of the constant interconnection of the analyzer systems of the human body, the integrity of the sensory reflection of the objective world.

Sensory Isolation and Its Consequences

S.i. - maintenance of the organism in conditions of exclusion from the environment of the maximum number of irritants.

Distinguish 3 types of isolation conditions:

1) absolute nullification of the receipt of irritations (sensory hunger);

2) elimination of stimuli that carry information, but without reducing the strength of the energy impact falling on the receptors;

3) reduction of the sensory environment to a series of simple monotonous and repetitive stimuli.

The 1st condition leads to S. and., the last 2 to perceptual isolation.

The study uses a number of indicators: verbal reports of the subjects, the results of perceptual, mnemonic and intellectual tests, motor activity, cardiac activity, etc.

Researches: in the conditions of S. and. the flow of perceptual processes is disturbed, visual and auditory illusions arise, sociability, clarity of behavior and the ability to think are sharply reduced.During the monotonous hours of the experiment, the subject tries to give meaning to the experimental situation, to make it informative (for example, the subjects try to understand the nature of food, determine the intervals between food servings, count inhalations and exhalations, etc.). They try to compensate for the absence of external stimuli with memories or imagination, but these pictures soon become intrusive, uncontrollable, turn into hallucinations. Feel - the necessary conditions for the functioning of the mind as a whole. A number of researchers note the great importance of the subject's past experience for the outcome of the experiment in S.'s conditions and. The nature of human behavior in the new conditions depends on its internal resources. Obviously, there is a category of people who are easier to manage with their inner world. (T. P. Zinchenko)

The concept of threshold in classical psychophysics

Since sensations depend on external stimuli,the question arose about the nature of this dependence, i.e. about the basic laws to which it obeys. This is the central question of psychophysics. Its foundations were laid by the studies of E. Weber and G. Fechner (“Elements of Psychophysics”).The fundamental question of psychophysics is the question of thresholds.

There are absolute and difference thresholds.

It has been found that not all stimuli cause sensations. It may be so weak that it does not cause any sensation. A known minimum intensity of irritation is needed in order to evoke sensations. The minimum irritation that causes sensation is calledlower absolute limit. IN upper absolute threshold -the maximum intensity possible to experience a given quality

In addition to the thresholds of absolute sensitivity, sensations are also characterized by thresholds of sensitivity to discrimination. The minimum amount of stimulus that causes subtledifferences in feelings, is called difference threshold.

E. WEBER found that a certain ratio between the intensities of two stimuli is required in order for them to give different sensations. This ratio is expressed in the law, established by Weber:the ratio of the additional stimulus to the main one should be a constant value.

Further studies showed that the law is valid only for stimuli of average magnitude: when approaching absolute thresholds, the magnitude of the increase passes to be constant.

The dependence of the intensity of sensation on the physical strength of the stimulus acting on the analyzer is mathematically expressed in the basic law of psychophysics, called"Weber-Fechner law": If the strength of the stimulus increases exponentially, then the intensity of the sensation increases in arithmetic progression.So, a chandelier with 8 light bulbs seems to us as much brighter than a 4-light chandelier as much as a 4-light chandelier is brighter than a 2-light chandelier. That is, the number of light bulbs should increase several times, so that it seems to us that the increase in brightness is constant.

The problem of measuring sensations. Myself Fechner proposed three psychophysical methods, which entered psychology under the name of basic methods.These methods aim to determine the thresholds.

1. Border method (barely noticeable differences, minimal changes or serial study). The compared stimulus changes in small steps both in increase and decrease. The subject at each measurement of the stimulus must say less than, equal to or more than the standard. As a result of the experiment, the values ​​of the variable stimulus corresponding to the change in response categories are determined. Atdefining an absolute thresholdstandard stimulusnot presentedand the task of the subject is to answer whether there is a stimulus or not.

habituation erroris the tendency to keep the answer "yes" in the descending ranks (with a decrease in stimulus) or the answer "no" in the ascending ranks.Anticipation (or expectation) errorhas the opposite character. The main purpose of alternating ascending and descending rows is to balance out any of the persistent errors, if any.

2. Installation method(mean error, reproduction or trimming method). 2 stimuli, the subject adjusts this stimulus to the standard (it seems to be equal to the standard). Repeat several times, and then calculate the average value and the variability of the test subject's settings. The mean of the trims (sets) is a direct measure of the subjective equality point, and the variability of the trims allowed by the subjects can be used to calculate the difference threshold.When determining the absolute thresholdthe subject repeatedly sets the value of the variable stimulus, which, in his opinion, is the lowest among the detected stimuli. The average of these settings is taken as the absolute threshold.

3. Method of constant stimuli(method of true and false cases or method of frequencies). This method concerns the identification of stimuli lying in the transition zone between perceived and non-perceived.If a stimulus or a difference between stimuli is perceived in 50% of cases, then they respectively indicate the position of the absolute and difference thresholds.In order to get a picture of the entire transition zone, 5-9 different stimuli are usually chosen, ranging from rarely noticed to almost always noticed stimuli. When measuring the absolute threshold, stimuli are also selected that lie on either side of the stimulation threshold or the absolute threshold. There are usually two categories of answers - "yes" and "no". Empty samples of the trap should be included so that the subject does not know about them. The absolute threshold is usually taken as the value of the stimulus at which it is perceived in 50% of cases.

The concept of subsensory range.

It has long been known that far from everything that is perceived by a person and determines his behavior is realized.

Subsensory range- the zone of human sensitivity to imperceptible irritations.

The subsensory area exists in both normal and pathological conditions. Its limits strongly depend on the functional state of a person and range from 5 to 12 dB for hearing.

A complete and accurate characterization of a person's sensory capabilities can only be obtained with the help of involuntary reactions.

Practical importance:in a number of cases, objective reactions represent the only way to measure sensitivity: in young children who have not yet fully mastered speech, with brain pathologies associated with speech impairment, with simulation of insensitivity, etc., where it is desirable to measure sensitivity without drawing the subject's attention to irritants.

All sensations can be characterized in terms of their properties. Moreover, properties can be not only specific, but also common to all types of sensations. The main properties of sensations include:

quality,

intensity,

duration,

spatial localization,

absolute and relative thresholds of sensations

Quality - this is a property that characterizes the basic information displayed by a given sensation, distinguishing it from other types of sensations and varying within this type of sensation. For example, taste sensations provide information about certain chemical characteristics of an object: sweet or sour, bitter or salty. The sense of smell also provides information about the chemical characteristics of the object, but of a different kind: the smell of flowers, the smell of almonds, the smell of hydrogen sulfide, etc.

It should be noted that often, when speaking about the quality of sensations, they mean the modality of sensations, since it is the modality that reflects the main quality of the corresponding sensation.

Intensity sensation is its quantitative characteristic and depends on the strength of the acting stimulus and the functional state of the receptor, which determines the degree of readiness of the receptor to perform its functions. For example, with a runny nose, the intensity of perceived odors can be distorted.

Duration Feelings are a temporal characteristic of the sensation that has arisen. It is also determined by the functional state of the sense organ, but mainly by the time of action of the stimulus and its intensity. It should be noted that sensations have a so-called latent (hidden) period. When a stimulus is applied to 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 example, for tactile sensations, it is 130 ms, for pain - 370 ms, and for taste - only 50 ms.

And finally for sensations characteristic spatial localization irritant. 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 sensation begins to develop immediately after the birth of the child. Shortly after birth, the baby begins to respond to stimuli of all kinds. However, there are differences in the degree of maturity of individual feelings and in the stages of their development. Immediately after birth, the child's skin sensitivity is more developed. When born, the baby trembles due to the difference in the temperature of the mother's body and air temperature. A newborn child also reacts to touch, and his lips and the entire area of ​​\u200b\u200bthe mouth are most sensitive. It is likely that a newborn can feel not only warmth and touch, but also pain. Already by the time of birth, the child has a highly developed taste sensitivity. Newborn children react differently to the introduction of a solution of quinine or sugar into their mouth. A few days after birth, the baby distinguishes mother's milk from sweetened water, and the latter from plain water. From the moment of birth, the child's olfactory sensitivity is already sufficiently developed. A newborn child determines by the smell of mother's milk whether the mother is in the room or not. If the child ate mother's milk for the first week, then he will turn away from cow's milk only when he smells it. However, olfactory sensations that are not related to nutrition develop over a long period of time. They are poorly developed in most children, even at the age of four or five. Vision and hearing go through a more complicated path of development, which is explained by the complexity of the structure and organization of the functioning of these sensory organs and their lesser maturity at the time of birth. In the first days after birth, the child does not respond to sounds, even very loud ones. This is due to the fact that the ear canal of the newborn is filled with amniotic fluid, which resolves only after a few days. Usually the child begins to react to sounds during the first week, sometimes this period is delayed up to two or three weeks. The child's first reactions to sound are in the nature of general motor excitation: the child throws up his arms, moves his legs, and utters a loud cry. Sensitivity to sound is initially low, but increases in the first weeks of life. After two or three months, the child begins to perceive the direction of the sound, turns his head towards the source of the sound. In the third or fourth month, some babies begin to respond to singing and music. As for the development of speech hearing, the child first of all begins to respond to the intonation of speech. This is observed in the second month of life, when the gentle tone has a calming effect on the child. Then the child begins to perceive the rhythmic side of speech and the general sound pattern of words. However, the distinction of speech sounds occurs by the end of the first year of life. From this moment, the development of speech hearing proper begins. First, the child develops the ability to distinguish between vowels, and at a subsequent stage, he begins to distinguish between consonants. The child's vision develops most slowly. The absolute sensitivity to light in newborns is low, but increases markedly in the first days of life. From the moment the visual sensations appear, the child reacts to light with various motor reactions. Color differentiation grows slowly. It has been established that the child distinguishes color as early as the fifth month, after which he begins to show interest in all kinds of bright objects. The child, beginning to feel light, at first cannot see objects. This is due to the fact that the movements of the child's eyes are not coordinated: one eye may look in one direction, the other in the other, or may even be closed. The child begins to control the movement of the eyes only by the end of the second month of life. He begins to distinguish objects and faces only in the third month. From this moment begins a long development of the perception of space, the shape of an object, its size and distance. In relation to all types of sensitivity, it should be noted that absolute sensitivity reaches a high level of development already in the first year of life. The ability to distinguish sensations develops somewhat more slowly. In a child of preschool age, this ability is developed incomparably lower than in an adult. The rapid development of this ability is noted in the school years. It should also be noted that the level of development of sensations in different people is not the same. This is largely due to the genetic characteristics of a person. - More details at Referatwork.ru: http://referatwork.ru/psyhology-2014/section-18.html

There are two types of sensitivity: absolute sensitivity and discrimination sensitivity. Absolute sensitivity is understood as the ability of the sense organs to respond to the smallest, weakest effects of stimuli. Distinction sensitivity, or difference sensitivity, is the ability to sense subtle differences between stimuli.

Lower absolute threshold of sensitivity- the minimum strength of the stimulus, causing a barely noticeable sensation. This is the threshold of conscious recognition of the stimulus.

Upper absolute threshold of sensitivity called the maximum strength of the stimulus, at which there is still an adequate sensation to the acting stimulus. A further increase in the strength of stimuli acting on our receptors causes only a painful sensation in them (for example, an ultra-loud sound, a blinding light).

The value of absolute thresholds, both lower and upper, varies depending on various conditions: the nature of the activity and age of the person, the functional state of the receptor, the strength and duration of stimulation, etc.

The sensation does not arise immediately, as soon as the desired stimulus begins to act. Between the onset of the action of the stimulus and the appearance of sensation, a certain time passes. It is called the latency period. Latent (temporary) period of sensation- the time from the onset of the stimulus to the onset of sensation. During the latent period, the energy of the acting stimuli is converted into nerve impulses, they pass through specific and non-specific structures of the nervous system, and they switch from one level of the nervous system to another.

the law of constancy of the magnitude of the increment of the stimulus was established, independently of each other, by the French scientist P. Bouguer and the German scientist E. Weber and was called the Bouguer-Weber law. Bouguer-Weber law- a psychophysical law expressing the constancy of the ratio of the increment in the magnitude of the stimulus, which gave rise to a barely noticeable change in the strength of sensation to its original value:

Where: I- the initial value of the stimulus, D I- its increment, TO - constant.

Another identified pattern of sensations is associated with the name of the German physicist G. Fechner (1801-1887). Due to the partial blindness caused by observing the sun, he took up the study of sensations. At the center of his attention is the long-known fact of differences between sensations depending on what was the initial magnitude of the stimuli that caused them. G. Fechner drew attention to the fact that similar experiments were carried out a quarter of a century earlier by E. Weber, who introduced the concept of “barely noticeable difference between sensations”. It is not always the same for all kinds of sensations. This is how the idea of ​​the thresholds of sensations appeared, that is, the magnitude of the stimulus that causes or changes the sensation.

Investigating the relationship that exists between changes in the strength of stimuli affecting the human senses and the corresponding changes in the magnitude of sensations, and taking into account the experimental data of Weber, G. Fechner expressed the dependence of the intensity of sensations on the strength of the stimulus by the following formula:

where: S is the intensity of sensation, J is the strength of the stimulus, K and C are constants.

According to this provision, which is called basic psychophysical law, the intensity of sensation is proportional to the logarithm of the strength of the stimulus. In other words, with an increase in the strength of the stimulus in a geometric progression, the intensity of the sensation increases in an arithmetic progression. This ratio was called the Weber-Fechner law, and G. Fechner's book Fundamentals of Psychophysics was of key importance for the development of psychology as an independent experimental science.

QUESTION 5 FEELING- direct sensual reflection of the individual properties of the object. They make up: sensory-perceptual level of mental reflection. At the sensory-perceptual level, we are talking about those images that arise from the direct impact of objects and phenomena on the senses.

The image is the result of perception, therefore the properties of the image = the properties of the perceived object. It can be perceptual (actually, perception) and non-perceptual (imagination, memory, thinking)

1. An image whose object is in the field of perception, i.e. resulting from the stimulation of our sensory systems - a perceptual image or image of perception. A prerequisite here is the activity of receptor systems, physiological processes of a peripheral order (a mental image (with closed eyes) is associated with the processes of the central nervous system). Perceptual images are divided:

By modality (visual, auditory, tactile);

On extraceptive / intraceptive, i.e. images of the external world / internal state (the latter are worse, because the receptors of feelings are poorer) - this division arose late. Small children and animals do not differentiate these states!

On conscious / unconscious images (in perception and imagination, most images are unconscious)

The paradox of the perceptual image - different people see the same object in different ways (even 1 person at different periods of life). Why? Because the image is not passively perceived, but actively built by the subject. It is not objects that perceive us, but we find them in the environment. Perceptual images, unlike non-perceptual ones, have a sensory basis. Perceptual image properties:

Reality - a person believes in the objective existence of the perceived object, the images of perception live in real time and space;

Objectivization - images are projected outward, bulging out into the space of the external world;

Integrity / objectivity - the perception is not the sum of heteromodal sensations, but a holistic object;

Polymodality is the organic unity of the data of various sense organs.

Constancy - constancy - the images of objects are constant and do not depend on the conditions of perception (lighting) and the properties of the subject itself (ex. from his appearance), i.e. this is the independence of the properties of a familiar object from the conditions of its perception (it is violated in children - they can be afraid of their father in the image of D. Moroz)

Significance - ex., looking at the spoon, we already see its function, influencing social and individual experience.

An image whose object is outside the process of perception is a non-perceptual image - when, without seeing the object itself, we imagine it, i.e. we do not have a real image, but we have an image associated with the processes of imagination, memory, thinking (ex., the image of memory is a former percept) Non-perceptual images have a quasi-sensory character.

- mental image: an image of imagination or memory, arises without the participation of peripheral nervous processes and is created by human experience or creativity; can be visual, auditory or any other sensory modality, as well as purely verbal .;

- synesthesia: accompaniment of perceptual sensations of one modality with pseudo-sensations of another modality (“assorted” feelings, color hearing, etc.); This interaction of the senses("color hearing", for example). This is a formal definition, and the idea of ​​synesthesia is that once the sense organs did not differ from each other, which has indirect confirmation: temperature sensitivity is directly used to assess the human appearance (a person is warm, cold, light, etc.)

- body diagram: a person's idea of ​​a certain system of activity that he controls, it also includes physical components that go beyond the body. Kinesthetic and temperature-tactile representations are considered important components of this image. The scheme of the body is included in the "I-image", but the latter is wider;

- phantom images: part of the image of one's own body, which remains even despite the loss of the corresponding bodily organ (usually a limb);

- hallucinatory images: occur without an external stimulus, the subject is convinced of the reality of an external object, this is a projection of the subject's internal image into the external world. Hallucinations differ from mental images in distinctness and detail. Their special case is hypnological images (on the verge of sleep and wakefulness);

- phosphenes: usually appear as desaturated spots or relatively stable patterned images. This term is also used to refer to dots or colored spots visible when the eye is not adequately stimulated, for example, by mechanical pressure or electric current.

- eidetic images: common in 70% of children - this is the result of the inertia of the visual system. Eidetic sees, but does not remember! a disappearing image within minutes and even hours (Rickel's experiments with a painting). According to Vygotsky, eidetism is widely represented among primitive peoples (it is the basis of topographic memory). In modern man, eidetism has been destroyed by higher mental functions and social influence.

All sensations can be characterized in terms of their properties. Moreover, properties can be not only specific, but also common to all types of sensation. The main properties of sensations include: quality, intensity, duration and spatial localization, absolute and relative thresholds of sensations.

Quality - this is a property that characterizes the basic information displayed by a given sensation, distinguishing it from other types of sensations and varying within this type of sensation. For example, taste sensations provide information about some of the chemical characteristics of an object:

sweet or sour, bitter or salty. The sense of smell also provides us with information about the chemical characteristics of the object, but of a different kind: the smell of flowers, the smell of almonds, the smell of hydrogen sulfide, etc.

It should be borne in mind that very often, when talking about the quality of sensations, they mean the modality of sensations, since it is the modality that reflects the main quality of the corresponding sensation.

Intensity sensation is its quantitative characteristic and depends on the strength of the acting stimulus and the functional state of the receptor, which determines the degree of readiness of the receptor to perform its functions. For example, if you have a runny nose, the intensity of perceived odors may be distorted.

Duration Feelings are a temporal characteristic of the sensation that has arisen. It is also determined by the functional state of the sense organ, but mainly by the time of action of the stimulus and its intensity. It should be noted that sensations have a so-called patent (hidden) period. When a stimulus is applied to 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 example, for tactile sensations, it is 130 ms, for pain - 370 ms, and 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. This inertia of sensations is manifested in the so-called aftereffect. A visual sensation, for example, has some inertia and does not disappear immediately after the cessation of the action of the stimulus that caused it. The trace from the stimulus remains in the form of a consistent image. Distinguish between positive and negative series

Fechner Gustav Theodor(1801 -1887) - German physicist, philosopher and psychologist, founder of psychophysics. Fechner is the author of the programmatic work "Elements of Psychophysics" (1860). In this work, he put forward the idea of ​​creating a special science - psychophysics. In his opinion, the subject of this science should be the regular correlations of two types of phenomena - mental and physical - functionally interconnected. The idea put forward by him had a significant impact on the development of experimental psychology, and the research that he conducted in the field of sensations allowed him to substantiate several laws, including the basic psychophysical law. Fechner developed a number of methods for indirect measurement of sensations, in particular three classical methods for measuring thresholds. However, after studying the successive images caused by the observation of the sun, he partially lost his sight, which forced leave him psychophysics and philosophy. Fechner was a comprehensively developed person. So, he published several satirical works under the pseudonym "Doctor Mises".

images. positive serial image corresponds to the initial irritation, consists in maintaining a trace of irritation of the same quality as the current stimulus.

Negative serial image consists in the appearance of a quality of sensation that is opposite to the quality of the irritant. For example, light-darkness, heaviness-lightness, heat-cold, etc. The appearance of negative consecutive images is explained by a decrease in the sensitivity of this receptor to a certain effect.

And finally, sensations are characterized spatial localization irritant. 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.

All of the above properties to some extent reflect the qualitative characteristics of sensations. However, the quantitative parameters of the main characteristics of sensations are no less important, in other words, the degree sensitivity. The human sense organs are surprisingly fine working apparatuses. Thus, Academician S. I. Vavilov experimentally established that the human eye can distinguish a light signal of 0.001 candles at a distance of a kilometer. The energy of this stimulus is so small that it would take 60,000 years to heat 1 cm3 of water by 1°C with its help. Perhaps no physical device has such sensitivity.

There are two types of sensitivity: absolute sensitivity And sensitivity to difference. By absolute sensitivity is meant the ability to sense weak stimuli, and by difference sensitivity is the ability to sense subtle differences between stimuli. However Not any irritation causes sensation. We do not hear the ticking of the clock in the other room. We do not see stars of the sixth magnitude. In order for a sensation to arise, the strength of the stimulus must have a certain amount.

12.Adaptation and sensitization of sensations

adaptation called a decrease or increase in the sensitivity of the analyzers as a result of continuous or prolonged exposure to stimuli. Due to adaptation, sensations that were sharp and strong at the initial stimulation of the receptor, then, with the continuous action of the same stimulation, weaken and may even disappear altogether. An example is adaptation to long-acting odors. In other cases, adaptation is expressed, on the contrary, in an increase in sensitivity. For example, during the transition from light to darkness, we do not distinguish objects around us. However, after some time, this feeling becomes possible.

Sensitization is called an increase in the sensitivity of analyzers in connection with an increase in the excitability of the cerebral cortex under the influence of certain stimuli. For example, the intake of caffeine or any other stimulants enhances the nervous activity of the cortex, in connection with which the sensitivity of the analyzers also increases: auditory, visual, tactile and other sensations begin to flow more clearly than under normal conditions.

The sensitivity of some analyzers may increase under the influence of the simultaneous activity of other analyzers. For example, when the eye is irritated with light of optimal intensity, at which the visual function is carried out easily and quickly, sensitivity to sounds also increases at the same time; visual acuity and color sensitivity increase with simultaneous prolonged exposure to moderate sounds, sensations of cold increase auditory and visual sensitivity; on the contrary, hot temperatures and a stuffy atmosphere lead to their decrease (S. V. Kravkov). Rhythmic auditory sensations contribute to an increase in musculoskeletal sensitivity: we feel and perform our movements better if physical exercises are accompanied by music.

The physiological basis of sensitization of sensations is the processes of interconnection of analyzers. The cortical parts of some analyzers are not isolated from others; they take part in the general activity of the brain. In this regard, the movement of nervous processes in the central sections of some analyzers, according to the laws of irradiation and mutual induction, is reflected in the activity of other analyzers.

This relationship is strengthened when the functions of different analyzers are involved in some common activity. For example, musculo-motor and auditory analyzers can be organically connected with the performance of movements (the nature of the sound corresponds to the nature of the movements), and then one of them enhances the sensitivity of the other.

The sensitivity of the analyzers sometimes also increases due to the fact that they have not been affected by the corresponding stimuli for a long time. For example, the sensitivity of the eye to light after a 30-40 minute stay in the dark can increase 20,000 times.

13. Interaction of sensations and synesthesia

The individual sense organs that we have just described do not always work in isolation. They can interact with each other, and this interaction can take two forms.

On the one hand, individual sensations can influence each other moreover, the work of one sense organ can stimulate or inhibit the work of another sense organ. On the other hand, there are deeper forms of interaction in which the sense organs work together causing a new, maternal kind of sensitivity, which in psychology is called synesthesia.

Let us dwell separately on each of these forms of interaction. Research conducted by psychologists (in particular, the Soviet psychologist S. V. Kravkov), showed that the work of one sense organ does not remain without influence on the course of the work of other sense organs.

So, it turned out that sound stimulation (for example, whistling) can sharpen the work of visual sensation, increasing its sensitivity to light stimuli. In the same way, some odors also affect, increasing or decreasing light and auditory sensitivity. A similar influence of some sensations on other sensations, apparently, occurs at the level of the upper parts of the trunk and the thalamus, where the fibers that conduct excitations from various sense organs approach each other and the transfer of excitations from one system to another can be carried out especially successfully. The phenomena of mutual stimulation and mutual inhibition of the functioning of the sense organs are of great practical interest in situations where it becomes necessary to artificially stimulate or suppress their sensitivity (for example, during flight at dusk in the absence of automatic control).

Another form of interaction between the sense organs is their joint work, in which the qualities of sensations of one type (for example, auditory) are transferred to another type of sensation (for example, visual). This phenomenon of the transfer of qualities from one modality to another is called synesthesia.

Psychology is well aware of the facts of "colored hearing", which turns on in many people and is especially clearly manifested in some musicians (for example, in Scriabin). So, it is widely known that we regard high sounds as “light”, and low ones as “dark”. The same applies to odors: some odors are known to be rated as "light" and others as "dark".

These facts are not random or subjective, their regularity was shown by a German psychologist Hornbostel, who presented the subjects with a series of odors and offered to correlate them with a series of tones and with a series of light shades. The results showed great consistency, and, most interestingly, the odors of substances whose molecules included a large number of carbon atoms were associated with darker shades, and the odors of substances whose molecules included few carbon atoms were associated with light shades. This shows that synesthesia is based on objective (still insufficiently studied) properties of agents affecting a person.

It is characteristic that the phenomenon of synesthesia is not distributed equally among all people. It is especially clearly manifested in people with increased excitability of subcortical formations. It is known that it prevails in hysteria, can increase markedly during pregnancy and can be artificially induced by the use of a number of pharmacological substances (for example, mescaline).

In some cases, the phenomena of synesthesia are manifested with exceptional distinctness. One of the subjects with exceptional severity of synesthesia - the famous mnemonist Sh. was studied in detail by Soviet psychology. This person perceived the weight of the voice as colored and often said that the voice of the person addressing him was "yellow and crumbly." The tones he heard caused him visual sensations of various shades (from bright yellow to dark silver or purple). Perceived colors were perceived by him as "voiced" or "muffled", "salty" or crispy. Similar phenomena in more obliterated forms occur quite often in the form of a direct tendency to "color" numbers, days of the week, names of months in different colors.

The phenomenon of synesthesia is of great interest for psychopathology, where its assessment can acquire diagnostic value.

The described forms of interaction of sensations are the most elementary and, apparently, proceed mainly at the level of the upper trunk and subcortical formations. There are, however, also more complex forms of sensory interaction or, as IP Pavlov called them, analyzers. It is known that we almost never perceive tactile, visual and auditory stimuli in isolation: perceiving objects of the external world, we see them with the eye, feel them by touch, sometimes perceive their smell, sound, etc. Naturally, this requires the interaction of the senses (or analyzers) and is provided by their synthetic work. This synthetic work of the sense organs proceeds with the closest participation of the cerebral cortex and, above all, those “tertiary” zones (“overlapping zones”), in which neurons belonging to different modalities are represented. These "overlap zones" (we talked about them above) provide the most complex forms of joint work of analyzers that underlie object perception. We will turn to the psychological analysis of the main forms of their work below.