First olfactory sensations. Transmission of olfactory signals

Taste sensations play an important role in human life. It is taste that determines the qualitative characteristics of food, provides the ability to feel and distinguish the chemical properties of substances entering the oral cavity.

Irritants of taste sensations are sweet, salty, sour, bitter. At the same time, taste buds located in different parts of the tongue react differently to the chemical properties of substances.

So, the tip of the tongue perceives predominantly sweet, the back of the tongue is more responsive to bitter, and the left and right edges are sensitive to sour.

Peripheral taste receptors of the tongue are associated with sensory neurons in cranial nerve ganglia. The central sections in the brain stem are represented by the sensory nuclei of these nerves, from which taste signals enter the thalamus and further to the new cerebral cortex. The taste system of sensations is connected by nerve pathways to the nerve center of smell in the brain. That is why when a runny nose appears, the sense of smell worsens and taste sensitivity decreases.

Olfactory sensations carry out psychophysiological functions that allow you to feel and distinguish by smell the chemical compounds in the air. The sense of smell plays an important role in establishing contact with various environmental objects and other people. The olfactory sensory system includes peripheral elements and higher parts of the brain.

It is necessary to pay attention to the fact that tactile sensations are the result of the processing of information received during stimulation of tactile, temperature, pain, muscle and joint receptors. This type of sensation is provided by the work of the skin and proprioceptive sensory systems and higher parts of the brain. The ability to touch plays a huge role in the lives of people who have lost sight, hearing or speech.

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Olfactory sensations

Closely related, smell and taste are varieties of chemical sensitivity. In lower animals, smell and taste are probably not divided. In the future, they differentiate. One of the biologically significant differences established between them is that taste is due to direct contact, while smell functions at a distance. The sense of smell belongs to distant receptors.

In animals, especially at the lower stages of the evolutionary series, the biological role of the sense of smell is very significant. Olfactory sensations largely regulate the behavior of animals in finding and choosing food, in recognizing individuals of the opposite sex, etc. The initial rudiment of the cerebral cortex in reptiles is mainly the central organ of smell.

Until recently, it was customary to think that the human sense of smell does not play a particularly significant role. Indeed, a person's sense of smell plays a much smaller role in the knowledge of the external world than vision, hearing, and touch. But its significance is still great due to the influence that the sense of smell has on the functions of the autonomic nervous system and on the creation of a positive or negative emotional background, coloring a person’s well-being in pleasant or unpleasant tones.

The sense of smell gives us a wide variety of different sensations, which are characterized by their usually bright positive or negative affective-emotional tone. It turned out to be very difficult to introduce a system into this diversity by establishing an unambiguous regular relationship between the chemical properties of a substance and its effect on the sense of smell.

The first attempt to reduce the variety of smells to several groups belongs to the famous naturalist Carl Linnaeus (1756). Its classification is mainly botanical. Lorry outlined a chemical classification. He distinguishes: 1) camphor, 2) narcotic, 3) essential, 4) volatile acidic, 5) alkaline odors. It is quite obvious that it is impossible to bring any unambiguously under these headings the substances that cause the sensation of smell. A. Bain relied on various secondary signs in his differentiation of smells. He distinguishes: 1) clean fresh odors, 2) depressing odors, 3) disgusting odors, 4) sweet odors, 5) offensive, 6) cutting, 7) ethereal, 8) burnt and 9) appetizing. This classification is clearly devoid of any consistency whatsoever. Zwardemaker's classification has gained considerable popularity, distinguishing between: 1) ethereal, 2) aromatic, 3) balsamic, 4) amber-musky, 5) alyl cacodyl, 6) burnt, 7) caprylic, 8) nasty (widerliche) and 9) disgusting (eckelhafte). ) smells. The Zwardemaker classification was sharply criticized by Genning, who noted eclecticism, theoretical inconsistency, and inconsistency with experimental data.

Genning tried to give a classification of odors based on the material provided by the psychological experiment; he distinguishes 6 basic smells, namely: spicy, floral, fruity, resinous, burnt and putrid, and tried to show that there is a continuity of transitions between smells, fundamentally the same as between sounds and colors. To do this, he depicted the whole variety of smells in the form of a prism, at the corners of which 6 main smells were located; the rest, according to Genning, should find their place among them. And this classification is by no means satisfactory.

Since the sensation of smell is caused by exposure to chemicals, an objective classification of odors would have to be based on a one-to-one correlation of the smell with the chemical properties of the substance that causes it. A number of attempts have recently been made in this direction, the most significant of which belongs to Hornbostel.

Olfactory sensations arise when certain gaseous substances enter the nose along with the inhaled air.

The olfactory region is the uppermost part of the mucous membrane of the nasal cavity. The entire surface of the olfactory region is approximately 5 sq. cm. Odorants can get here only in two ways. Firstly, when inhaled, and secondly, odorous substances can be felt when exhaling, when substances penetrate from the choanae (this is especially the case when eating).

In order for an odorous substance to evoke an olfactory sensation, it must be capable of evaporation and dissolution in water. Those of the substances that are easily absorbable and soluble in lipids may be the best irritants. Of the almost two million inorganic compounds, only a fifth excites the sense of smell. The sensitivity to smell in humans (and even more so in animals) is very high. AT g/cm 3 milestone values, according to Zwardemaker, for example, are: acetone 0.4 -3, camphor 1.6∙10 -11, valeric acid 2.1∙10 -12, etc. Many animals in whose life the sense of smell plays an important role , can distinguish even smaller values.

Due to the role that the sense of smell plays in tuning the autonomic nervous system, which performs adaptive-trophic functions in relation to all types of sensitivity, the sense of smell can influence the thresholds of various sense organs.

Of all the sensations, perhaps none are so widely associated with the emotional sensual tone as the olfactory ones: almost every olfactory sensation has a more or less pronounced character of pleasant or unpleasant; many evoke a very strong positive or negative emotional reaction. There are unbearable smells and others - intoxicating. Some people are especially sensitive to their effects, and the sensitivity of many in this regard is so great that it has given rise to an entire industry - perfumery.

Taste sensations

Taste sensations, like olfactory sensations, are due to the chemical properties of things. As with smells, there is no complete, objective classification for taste sensations.

From the complex of sensations caused by taste substances, four main qualities can be distinguished - salty, sour, sweet and bitter.

Taste sensations are usually accompanied by olfactory sensations, and sometimes also sensations of pressure, heat, cold, and pain. The caustic, astringent, tart taste is due to a whole complex of various sensations. It is this more or less complex complex that usually determines the taste of the food we eat.

Taste sensations arise when soluble and diffusible substances, i.e., substances with a relatively low molecular weight, are exposed to the taste areas. The main taste area is the mucous membrane of the tongue, especially its tip, edges and base; the middle of the tongue and its lower surface are devoid of taste sensitivity.

Different taste regions have different sensitivities to salty, sour, sweet, and bitter sensations. The most sensitive on the tongue: the tip to sweet, the edges to sour, and the base to bitter. Therefore, it is assumed that for each of the four basic taste sensations there are special organs.

Of the theories of taste, two are of greatest importance - the theory of Renquiem and the ionic theory of P. P. Lazarev.

Renquiem's theory is based on the absorption of flavor by sensitive cells and emphasizes the speed at which this process takes place.

The ionic theory of taste sensitivity of Lazarev comes from the ionic theory of excitation. Acad. Lazarev believes that 4 special sensitive substances are laid in the papillae of the tongue, the corresponding decomposition of which under the influence of taste substances causes 4 main taste sensations - sour, salty, sweet and bitter. However, an unambiguous regular relationship between the chemical structure of a substance and its taste effect has not yet been established; sour taste is due to the action of hydrogen ions, the concentration of which is characteristic of each acid; a sensation of salty taste is generated by some salts; sensations of bitter and sweet are generated by substances of very different chemical structures.

By combining 4 types of primary stimuli, one can obtain a substance that would be indifferent in taste and would give the taste of distilled water. This, according to P.P. Lazarev, corresponds in vision to obtaining white color. Acad. P.P. Lazarev and his collaborators conducted a series of studies on the synthesis of the taste of substances (tea, coffee, fruit juices) that give complex taste sensations.

The same general laws apply to taste as to the other senses, in particular the law of adaptation.

An important role in taste sensations is played by the process of compensation, i.e., the drowning out of some taste sensations (salty) by others (sour). So, for example, the boundary value established under certain conditions for bitter at 0.004% solutions of quinine in the presence of common salt rises to 0.01% quinine solution, and in the presence of hydrochloric acid - up to 0.026%. Under certain conditions of compensation, one can reach the complete neutralization of the bitter taste and the appearance of some new, mixed taste. It is possible, for example, to choose such concentrations of table salt at which the solution has neither salty nor sweet taste.

Along with compensation in the field of taste sensations, contrast phenomena are also observed. For example: the sensation of the sweet taste of a sugar solution is enhanced by the admixture of a small amount of table salt. Distilled water after rinsing the mouth with potassium chloride or diluted sulfuric acid seems distinctly sweet. All these facts testify to the presence in the field of taste of the processes of interaction within even one sense organ. In general, the phenomena of interaction, adaptation, temporary aftereffect of a chemical stimulus, not only adequate, but also inadequate, appear very clearly in the field of taste.

Due to the role of taste in adjusting the emotional state through the autonomic nervous system, taste, along with smell, affects the thresholds of other receptor systems, such as visual acuity and hearing, the state of skin sensitivity and proprioceptors.

Taste sensations generated by chemicals coming from the external environment, affecting autonomic functions, can cause a pleasant or unpleasant emotional background of well-being. The custom of combining festivity with feasts indicates that the practice takes into account the ability of taste sensitivity, associated with the impact on the autonomic nervous system, to influence the sensual tone of general well-being.

The role of taste sensations in the process of eating is determined by the state of need for food. As this need intensifies, the exactingness decreases: a hungry person will eat less tasty food; a well-fed person will be seduced only by what he finds seductive in terms of taste.

Like olfactory sensations associated with effects on the autonomic nervous system, taste sensitivity can also give a variety of more or less sharp and pleasant sensations. There are people - gourmets who especially cultivate them in order to extract the maximum pleasure from them. Such a concentration of human interests on taste sensations is possible, of course, only in the conditions of an idle and poor in content, spiritually impoverished life. Normally, a person who lives by more or less significant social and cultural interests does not live in order to eat, but eats in order to live and work. Therefore, subtle shades of taste sensations in the system of human behavior play a very subordinate role.

While eating, a person is interested not only in the quantity of food, but also in its taste. Taste is a psychophysiological function that provides the ability to sense and distinguish the chemical properties of substances entering the oral cavity. Irritants of taste sensations - sweet, salty, sour, bitter. Taste receptors (chemoreceptors) are located on the surface of the tongue (except for its lower part), palate, tonsils and back of the throat.

The relative concentration of receptors in these areas is not the same. So, the tip of the tongue reacts mainly to sweet, the back of the tongue is more sensitive to bitter, and the left and right edges are more sensitive to sour.

Peripheral taste receptors of the tongue are associated with sensory neurons in cranial nerve ganglia. The central sections in the brain stem are represented by the sensitive nuclei of these nerves, and which taste signals enter the thalamus and then to the new cerebral cortex.

The gustatory system of sensations is nerve pathways (connected to the nerve center of the sense of smell of the brain. That is why there is a connection: with a runny nose, the sense of smell worsens and taste sensitivity decreases.

The sense of smell is involved in establishing contact with various environmental objects and with other people. The sense of smell is a psychophysiological function that allows you to feel and distinguish by smell the chemical compounds that are in the air. The olfactory sensory system includes peripheral elements and higher parts of the brain.

Irritants of olfactory sensations are odorous substances contained in the air. Olfactory receptors, located in the upper part of the nasal cavity, perceive the odors of substances. Electrical signals are also formed here, which, through the olfactory nerve, enter the olfactory bulb - a part of the brain in the frontal lobe of the hemisphere.

There is no strict classification of odors. The following smells are usually distinguished: floral (rose, lily of the valley, etc.), burnt (tobacco, roasted coffee, etc.), aromatic (camphor, pepper), musky (musk, amber), onion (onion, iodine), goat (valerian, sweat), narcotic (hashish, opium), nauseating (faeces, rotten meat products). In this regard, sensations are also identified with the smell of the odorous substances listed above.

In terms of olfactory and gustatory sensations, people differ little, although there are people with increased sensitivity to smells and tastes of products (tasters, for example). Olfactory and gustatory sensations are influenced by other types of sensations. For example, the feeling of hunger sharpens the sensitivity to sweet and sour, and the smell of menthol causes a feeling of coolness.

It has been established that each person has his own, characteristic only for him, body odor. This fact, along with fingerprinting, is used by law enforcement agencies to identify individuals. And psychologists dealing with family and marriage problems recommend that a couple entering into marriage test themselves for smell compatibility.

A person learns the surrounding objects by touching them. At the same time, he receives information about their shape, surface, hardness, temperature. In such cases, it is said that a person cognizes the world through touch. Touch is a psychophysiological function that allows you to feel and distinguish the shape, size, nature of the surface and temperature of environmental objects. Naturally, these parameters can be determined only on the basis of a combination of movement and direct touch.

Tactile sensations arise on the basis of the processing of information received during irritation of temperature, tactile, pain, muscle and joint receptors. Thus, tactile sensations are provided by the work of the skin and proprioceptive sensory systems and, of course, the Higher parts of the brain.

The ability of a person to tactile sensations is widely used in restoring sight, hearing and speech to people who have lost them.

OLFACTORY SENSATIONS

(English) olfactory sensations) - a kind of sensations that reflect the chemical properties of volatile substances (called smells). Smells for a person are signs of an infinite number of objects and phenomena. In nature, there are approximately 60,000 different smells, simple and complex. Their combination can. b. infinitely varied. However, a person with a good sense of smell can learn to distinguish tens of thousands of both simple and complex odors.

Various systems for describing and classifying odors are known. At present, a classification that includes 4 main components: fragrant, sour, burnt, and putrefactive, the intensity of which is estimated on a conditional scale from 0 to 8, is in practical use. there are subtle individual differences. For example, a number of floral scents can be. accepted only by some people. This phenomenon is similar "color blindness". With the simultaneous action of 2 or more different odors on the olfactory receptors, masking, compensation or merging of odors is possible. The aesthetic effect of complex perfumery odors is based on the merging of smells - a “bouquet of smells”.

O.'s feature about. is their emotional impact on the body. Unpleasant odors can cause headaches in a person, , asthma, and reduce labor productivity. Therefore, in the workplace it is necessary to eliminate the sources of unpleasant odors or mask them. They are eliminated by ventilation, adsorption (absorption of gas by a porous material), absorption (absorption by a liquid or filter), masking with a more pleasant smell, ozone. (T. P. Zinchenko.)

Big psychological dictionary. - M.: Prime-EVROZNAK. Ed. B.G. Meshcheryakova, acad. V.P. Zinchenko. 2003 .

See what the "OLFUL SENSATIONS" are in other dictionaries:

olfactory sensations- fragrant garbage dump fragrant stench fetid fragrance fetid aroma fetid fragrance ... Dictionary of oxymorons of the Russian language

Olfactory organs*

Olfactory organs- organs by means of which the animal distinguishes the presence of random impurities in the air or water, which serve for respiration. O. organs play an extremely important role in the life of many animals. With the help of smell, the animal often finds food, avoids ... ... Encyclopedic Dictionary F.A. Brockhaus and I.A. Efron

EXTEROCEPTIVE SENSATIONS- [from lat. exter, exteris external, external capio take, take] sensations arising from the action of external stimuli on receptors located on the surface of the body. O. e. are divided into distant ones, the receptors of which respond to ... ... Psychomotor: Dictionary Reference

Olfactory cilia- Hair-like protrusions of olfactory cells in contact with the fluid that covers the mucous membrane of the olfactory epithelium, reacting to dissolved odorants and participating in the initial stage of the transmission of the olfactory sensation ... Psychology of sensations: a glossary

olfactory hallucinations- (h. olfactoriae) G. in the form of a sensation of any odors, often unpleasant; difficult to distinguish from olfactory illusions ... Big Medical Dictionary

Olfactory hallucinations- deceptions of smell in the form of imaginary various smells, both pleasant, fragrant, giving visible pleasure, and unpleasant, repulsive, depressing. Such smells can be perceived as arising somewhere from the outside (sometimes generating ... ... Encyclopedic Dictionary of Psychology and Pedagogy

Smell- a special specific feeling caused by the action of odorous substances on the upper part of the nasal mucosa. The olfactory organ is, therefore, the nose and a specially olfactory part of its mucous membrane, in which the endings branch ... ... Encyclopedic Dictionary F.A. Brockhaus and I.A. Efron

SMELL- SMELL, physical. chem. the process by which man and animal get an idea of smell. O. plays a particularly important role in animals, and in some of them O. (syn. flair) is very large; the ability to distinguish the faintest odors is in many ... Big Medical Encyclopedia

Smell- a special specific feeling caused by the action of odorous substances on the upper part of the nasal mucosa. The organ of smell is, therefore, the nose and a specially olfactory part of its mucous membrane, in which the endings branch ... ... Encyclopedia of Brockhaus and Efron

Olfactory sensations occur during penetration into the nose together with the inhaled air molecules of various substances.

The olfactory region is the uppermost part of the mucous membrane of the nasal cavity. The entire surface of the olfactory region is approximately 5 cm 2 . Odorants can get here only in two ways. Firstly, when inhaled, and secondly, odorous substances can be felt when exhaled, when substances penetrate from the choanae (this is especially the case when eating).<...>

TASTE

Taste sensations, like olfactory sensations, are due to the chemical properties of things. As with smells, there is no complete, objective classification for taste sensations.

From the complex of sensations caused by taste substances, four main qualities can be distinguished - salty, sour, sweet and bitter.

Different taste regions have different sensitivities to salty, sour, sweet, and bitter sensations. The most sensitive on the tongue: the tip to sweet, the edges to sour, and the base to bitter. Therefore, it is assumed that there are special organs for each of the four basic taste sensations.

The same general laws apply to taste as to other organs.

feelings, in particular the law of adaptation.

An important role in taste sensations is played by the process of compensation, i.e., the drowning out of some taste sensations (salty) by others (sour). For example, the boundary value established under certain conditions for bitter at 0.004% quinine solutions in the presence of common salt rises to 0.01% quinine solution, and in the presence of hydrochloric acid - up to 0.026%.<...>

Along with compensation in the field of taste sensations, contrast phenomena are also observed. For example, the sensation of the sweet taste of a sugar solution is enhanced by the admixture of a small amount of table salt. Distilled water, after rinsing the mouth with potassium chloride or dilute sulfuric acid, seems distinctly sweet. All these facts testify to the presence in the field of taste of the processes of interaction within even one sense organ. In general, the phenomena of interaction, adaptation, temporary aftereffect of a chemical stimulus, not only adequate, but also inadequate, appear very clearly in the field of taste.

Taste sensations play a significant role in setting the emotional state; through the autonomic nervous system, taste, along with smell, affects the thresholds of other receptor systems, such as visual acuity and hearing, the state of skin sensitivity and proprioceptors.

Taste sensations generated by chemicals entering from the external environment, influencing autonomic functions, can cause a pleasant or unpleasant emotional background of well-being. The custom of combining festivity with feasts indicates that the practice takes into account the ability of taste sensitivity, associated with the impact on the autonomic nervous system, to influence the sensual tone of general well-being.

Like olfactory sensations associated with effects on the autonomic nervous system, taste sensitivity can also give a variety of more or less sharp and pleasant sensations.<...>Although a normal person with significantly developed social and cultural interests does not live in order to eat, but eats in order to live and work. Therefore, subtle shades of taste sensations in the system of human behavior play a very subordinate role.

HEARING SENSATIONS

The special significance of hearing in humans is associated with the perception of speech and music.

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.

Sound waves have, firstly, different amplitude fluctuations. Under the amplitude of oscillation is meant the greatest deviation of the sounding body from the state of equilibrium or rest. The larger the amplitude of the oscillation, the stronger the sound, and, conversely, the smaller the amplitude, the weaker the sound. The sound strength of ear distance is directly proportional to the square of the amplitude. This force also depends on the source of the sound and on the medium in which the sound propagates. To measure the strength of sound, there are special devices that make it possible to measure it in units of energy.

Sound waves are different, secondly, but frequency or the duration of the oscillation. The wavelength is inversely proportional to the number of oscillations and directly proportional to the period of oscillation of the sound source. Waves of a different number of oscillations in 1 s or during the period of oscillation give sounds that are different in height: waves with oscillations of a large frequency (and a small period of oscillations) are reflected in the form of high sounds, waves with oscillations of a low frequency (and a large period of oscillations) are reflected in the form of low sounds.

The sound waves caused by the sounding body, the sound source, differ, thirdly, form fluctuations, i.e. the shape of that periodic curve in which the abscissas are proportional to time, and the ordinates are proportional to the removal of the oscillating point from its equilibrium position. The shape of the vibrations of a sound wave is reflected in the timbre of the sound - that specific quality by which sounds of the same height and strength on different instruments (piano, violin, flute, etc.) differ from each other.

The relationship between the shape of the vibration of a sound wave and the timbre is not unambiguous. If two tones have a different timbre, then it can definitely be said that they are caused by vibrations of different shapes, but not vice versa. Tones can have exactly the same timbre, and, however, their form of vibrations can be different. In other words, the waveforms are more varied and numerous than the tones heard by the ear.

Auditory sensations can be evoked as periodical oscillatory processes, and non-periodic with irregularly changing unstable frequency and amplitude of oscillations. The former are reflected in musical sounds, the latter in noises.

The musical sound curve can be decomposed in a purely mathematical way.

by the Fourier method into separate, superimposed sinusoids. Any sound curve, being a complex oscillation, can be represented as the result of more or less sinusoidal oscillations, with the number of oscillations per second increasing, as a series of integers 1,2,3, 4. The lowest tone, corresponding to 1, is called the main one. It has the same period as the complex sound. The remaining simple tones, which have twice, three times, four times, etc., more frequent vibrations, are called upper harmonic, or partial (partial), or overtones.

All audible sounds are divided into noises and musical sounds. The former reflect non-periodic oscillations of unstable frequency and amplitude, the latter - periodic oscillations. However, there is no sharp line between musical sounds and noises. The acoustic component of the noise often has a pronounced musical character and contains a variety of tones that are easily picked up by an experienced ear. The whistle of the wind, the squeal of a saw, various hissing noises with high tones included in them are sharply different from the hum and murmur noises characterized by low tones. The absence of a sharp boundary between tones and noises explains the fact that many composers are perfectly able to depict various noises with musical sounds (the murmur of a stream, the buzzing of a spinning wheel in the romances of F. Schubert, the sound of the sea, the clanging of weapons by N. A. Rimsky-Korsakov, etc. ).

In the sounds of human speech, both noises and musical sounds are also represented.

The main properties of any sound are: 1) his volume, 2) height and 3) timbre.

1. Volume. Loudness depends on the strength, or amplitude, of the vibrations of the sound wave. The power of sound and loudness are not equivalent concepts. The strength of sound objectively characterizes the physical process, regardless of whether it is perceived by the listener or not; loudness - the quality of the perceived sound. If we arrange the volumes of the same sound in the form of a series increasing in the same direction as the strength of the sound, and be guided by the steps of the increase in volume perceived by the ear (with a continuous increase in the strength of the sound), then it turns out that the volume grows much more slowly than the strength of the sound.

According to the Weber-Fechner law, the loudness of a certain sound will be proportional to the logarithm of the ratio of its strength J to the strength of the same sound at the threshold of hearing Jo:

In this equality, K is a proportionality factor, and L expresses a value characterizing the loudness of a sound whose strength is equal to J; it is commonly referred to as the sound level.

If the proportionality coefficient, which is an arbitrary value, is taken equal to one, then the sound level will be expressed in units called belov:

L = log J o B

In practice, it turned out to be more convenient to use units 10 times smaller; These units are called decibels. The coefficient K in this case, obviously, equals 10. Thus:

L = log J o d B

The minimum increase in volume perceived by the human ear is approximately 1dB.<...>

It is known that the Weber-Fechner law loses its force with weak stimuli; therefore, the loudness level of very weak sounds does not quantify their subjective loudness.

According to the latest work, when determining the difference threshold, one should take into account the change in the pitch of sounds. For low tones, the volume rises much faster than for high tones.

The quantitative measurement of the loudness directly perceived by our hearing is not as accurate as the auditory estimate of the pitch. However, dynamic designations have long been used in music, which serve to determine the magnitude of loudness in practice. These are the designations: prr(piano-pianissimo), pp(pianissimo), R(piano), tr(mezzo-piano), mf(mezzo forte), ff(fortissimo), fff(forte-fortissimo). Consecutive designations on this scale mean approximately doubling the volume.

A person can, without any preliminary training, evaluate changes in volume by a certain (small) number of times (by 2, 3, 4 times). In this case, doubling the volume is obtained approximately just with an increase of about 20 dB. Further evaluation of the increase in volume (more than 4 times) is no longer possible. Studies on this issue have given results that are sharply at odds with the Weber-Fechner law. They also showed significant individual differences in assessing loudness doubling.

When exposed to sound in the hearing aid, adaptation processes occur that change its sensitivity. However, in the field of auditory sensations, adaptation is very small and reveals significant individual deviations. The effect of adaptation is especially strong when there is a sudden change in the strength of the sound. This is the so-called contrast effect.

Loudness is usually measured in decibels. S. N. Rzhevkin points out, however, that the decibel scale is not satisfactory for quantifying natural loudness. For example, the noise on a full-speed metro train is estimated at 95 dB, while the ticking of a clock at a distance of 0.5 m is estimated at 30 dB. Thus, on the decibel scale, the ratio is only 3, while for immediate sensation, the first noise is almost immeasurably greater than the second.<...>

2. Height. The pitch of a sound reflects the frequency of the sound wave. Not all sounds are perceived by our ear. Both ultrasonics (sounds with a high frequency) and infrasounds (sounds with very slow vibrations) remain beyond our hearing. The lower limit of hearing in humans is approximately 15-19 vibrations; the upper one is approximately 20,000, and in some people the sensitivity of the ear can give various individual deviations. Both limits are variable, the upper one in particular depending on age; in older people, sensitivity to high tones gradually decreases. In animals, the upper limit of hearing is much higher than in humans; in a dog it goes up to 38,000 Hz (cycles per second).

When exposed to frequencies above 15,000 Hz, the ear becomes much less sensitive; the ability to distinguish pitch is lost. At 19,000 Hz, only sounds that are a million times more intense than at 14,000 Hz are extremely audible. With an increase in the intensity of high-pitched sounds, there is an unpleasant tickling sensation in the ear (touch of sound), and then a feeling of pain. The area of auditory perception covers more than 10 octaves and is limited from above by the threshold of touch, from below by the threshold of audibility. Within this area lie all the sounds perceived by the ear of various strengths and heights. The smallest force is required to perceive sounds from 1000 to 3000 Hz. The ear is the most sensitive in this area. G. L. F. Helmholtz also pointed out the increased sensitivity of the ear in the region of 2000-3000 Hz; he explained this circumstance by his own tone of the tympanic membrane.

The value of the threshold for distinguishing, or the difference threshold, height (according to T. Peer, V. Straub, B. M. Teplov) in the middle octaves for most people is in the range from 6 to 40 cents (a cent is a hundredth of a tempered semitone). The musically gifted children examined by L.V. Blagonadezhina had thresholds of 6-21 cents.

There are actually two height discrimination thresholds: 1) the simple discrimination threshold and 2) the direction threshold (W. Preyer and others). Sometimes, with small differences in pitch, the subject notices a difference in pitch, without, however, being able to tell which of the two sounds is higher.

Pitch, as it is usually perceived in noises and speech sounds, includes two different components - the pitch itself and the timbre characteristic.

In the sounds of a complex composition, the change in pitch is associated with a change in some timbre properties. This is explained by the fact that with an increase in the frequency of oscillations, the number of frequency tones available to our hearing aid inevitably decreases. In noise and speech hearing, these two height components are not differentiated. The isolation of pitch in the true sense of the word from its timbre components is a characteristic feature of musical hearing (BM Teplov). It takes place in the process of the historical development of music as a certain type of human activity.

One version of the two-component theory of pitch was developed by F. Brentano, and following him, based on the principle of octave similarity of sounds, G. Reves distinguishes between the quality and lightness of sound. By the quality of sound, he understands such a feature of the pitch, thanks to which we distinguish sounds within an octave. Under lordship - such a feature of its height, which distinguishes the sounds of one octave from the sounds of another. So, all “do” are identical qualitatively, but they are different in lordship. Even K. Stumpf subjected this concept to sharp criticism. Of course, there is an octave similarity (as well as a fifth similarity), but it does not determine any component of pitch.

M. McMayer, K. Stumpf, and especially W. Koehler gave a different interpretation of the two-component theory of height, distinguishing in it the actual height and the timbre characteristic of the height (lightness). However, these researchers (as well as E. A. Maltseva) differentiated the two components of height on a purely phenomenal level: they correlated two different and, in part, even heterogeneous properties of sensation with the same objective characteristic of a sound wave. B. M. Teplov pointed out the objective basis of this phenomenon, which consists in the fact that with an increase in height, the number of partial tones accessible to the ear changes. Therefore, the difference in timbre coloring of sounds of different pitches is actually only in complex sounds; in simple tones, it represents the result of transference.

Due to this interrelation between the actual pitch and timbre coloring, not only different instruments differ in their timbre from each other, but also sounds of different pitch on the same instrument differ from each other not only in pitch, but also in timbre coloring. This affects the relationship of various aspects of sound - its pitch and timbre properties.

3. Timbre. Timbre is understood as a special character or coloring of sound, depending on the relationship of its partial tones. The timbre reflects the acoustic composition of a complex sound, i.e. the number, order and relative strength of the partial tones (harmonic and non-harmonic) included in its composition.

According to Helmholtz, timbre depends on which upper harmonic tones are mixed in with the fundamental, and on the relative strength of each of them.

In our auditory sensations, the timbre of a complex sound plays a very significant role. Partial tones (overtones), or, in the terminology of N. A. Garbuzov, upper natural overtones, are also of great importance in the perception of harmony.

Timbre, like harmony, reflects the sound, which in its acoustic composition is consonance. Since this consonance is perceived as a single sound without acoustically distinguishing the incoming partial tones in it, the sound composition is reflected in the form of a sound timbre. Since hearing singles out partial tones of a complex sound, a perception of harmony arises. In reality, in the perception of music, there is usually a place for both. The struggle and unity of these two mutually contradictory tendencies is to analyze sound as consonance and perceive consonance as a single sound specific timbre coloration - is an essential aspect of any real perception of music.

Timbre coloring acquires a special richness due to the so-called vibrato(K. Sishore), which gives the sound of the human voice, violin, etc. great emotional expressiveness. Vibrato reflects periodic changes (pulsations) in the pitch and intensity of a sound.

Vibrato plays a significant role in music and singing; it is also represented in speech, especially emotional speech. Since vibrato is present in all peoples and in children, especially musical ones, occurring in them regardless of training and exercise, it is obviously a physiologically conditioned manifestation of emotional tension, a way of expressing feelings.

Vibrato in the human voice as an expression of emotionality has probably existed since there was a sound speech and people use sounds to express their feelings. Vocal vibrato arises as a result of the frequency of contraction of paired muscles, observed during nervous discharge in the activity of various muscles, not only vocal ones. Tension and discharge, expressed in the form of pulsation, are homogeneous with the trembling caused by emotional stress.

There is good vibrato and bad vibrato. Bad vibrato is one in which there is an excess of tension or a violation of the periodicity. Good vibrato is a periodic pulsation that includes a certain pitch, intensity and timbre and gives the impression of a pleasant flexibility, fullness, softness and richness of tone.

The fact that vibrato, being due to changes heights and intensity sound is perceived as timbre coloration, again reveals the internal interconnection of the various aspects of sound. When analyzing the pitch, it has already been found that the pitch in its traditional sense, that is, that side of the sound sensation, which is determined by the frequency of vibrations, including not only the pitch, in the proper sense of the word, but also the timbre component of lightness. Now it turns out that, in turn, in timbre coloration - in vibrato - the height is reflected, as well as the intensity of the sound. Various musical instruments differ from each other in timbre characteristics. <...>

SOUND LOCALIZATION

The ability to determine the direction from which sound comes is due to: the binaural nature of our hearing, that is, the fact that we perceive sound with two ears. The localization of sound in space is therefore denoted as binaural effect. People who are deaf in one ear only with great difficulty determine the direction of the sound and are forced to resort to head rotation and various indirect indicators for this purpose.

The binaural effect can be phase and amplitude. At phase binaural effect determining the direction from which the sound comes is due to the difference in the times of arrival of the same phases of the sound wave to the two ears. At amplitude binaural effect determining the direction of the sound is due to the difference in loudness obtained in the two ears. Localization of sounds based on the phase binaural effect is possible only for sounds of low frequencies (no more than 1500 Hz, and quite distinctly even only up to 800 Hz). For high-frequency sounds, localization is performed on the basis of the difference in loudness obtained in one and the other ear. There are certain relationships between phase and amplitude binaural effects. Some authors (R. Hartley, T. Frey) believe that the mechanisms of phase and amplitude localization always act together to some extent.

Under natural conditions, the spatial localization of sound is determined not only by the binaural effect, but by a set of data that serve to orientate in real space. An important role is played by the interaction of auditory data with visual data and the comprehension of the former based on the perception of real space.

To explain this thesis, I cite observations made by me during one meeting. The meeting took place in a very large radio-equipped hall. The speeches of the speakers were transmitted through several loudspeakers located to the left and right along the walls.

At first, sitting relatively far away, due to my myopia, I did not see the speaker and, not noticing how he ended up on the podium, I mistook his vaguely visible figure for the chairman. The voice (well known to me) of the speaker I distinctly heard on the left, it came from a nearby loudspeaker. After a while, I suddenly made out the speaker, or rather, I noticed how he made at first one, and then several more energetic hand gestures that coincided with voice stresses, and immediately the sound unexpectedly moved - he was walking towards me right in front, from the place where stood the speaker.

A colleague, a teacher-professor, was sitting next to me, blind himself. It caught my eye that he was sitting in a half turn, his whole body turned to the left, stretched tensely towards the loudspeaker; in this position he sat through the entire meeting. Noticing his strange posture, at first I did not understand what caused it. Since he did not see, for him, obviously, all the time, as for me at first, until I made out the speaker, the sound source was localized in the direction of the loudspeaker. Orienting on the basis of auditory sensations, my neighbor also localized the podium in the direction of the loudspeaker. Therefore, he sat in a half-turn, wanting to sit facing the presidium.

Taking advantage of the break, I moved to the back seat on the right. From this distant place I could not see the speaker; more precisely, I vaguely saw his figure, but did not see if he spoke (moving lips, gesticulating, etc.): the sound stopped coming from the podium, as it was before the break, he again moved to the loudspeaker, this time to the right of me. At the risk of somewhat disturbing the order of the meeting, I moved closer to the speaker. At first, there was no change in sound localization. But then I began to peer into the speaker and suddenly noticed his gestures, and immediately the sound moved to the podium; I began to hear him where I saw the speaker.

As the next speaker went to the podium, I followed him with my eyes to the podium and noticed that from the moment he entered the podium, a sound rushed and the sound of his speech came from the podium.

But during his speech, I began to make notes to myself and lost him, thus, out of sight. Having stopped writing, I noticed with surprise that the voice of the same speaker was already reaching me not in front, from where he was standing, but on the right, on the side, localizing in the nearest loudspeaker.

During this session, 15 times the sound moved with the same regularity. The sound moved to the podium or returned to the nearest speaker again, depending on whether I saw the person speaking (mouth movement, gestures) or not. In particular, when the speaker began to gesticulate noticeably for me and I saw what he was saying, the sound moved towards him, I heard him on the podium; when the speaker stopped gesticulating and I did not see the person speaking directly in front of me, the sound passed to the loudspeaker. At the same time, I did not imagine, but perceived or even felt the sound here and there.

It is worth noting that I, of course, very quickly installed and then knew perfectly well where the speaker was. But I needed to see the speaker, and not just know where he was, in order for the sound to travel to him. Abstract knowledge did not affect the immediate spatial localization of sound. However, by the end of the meeting, after about 2 hours, during which these movements took place, which I specially observed and over which I actually experimented, the situation changed, I could already achieve the movement of sound to the podium, fixing my mental attention on the speaker, transferring the speaker to the podium in his presentation.

Whether we localize sound based on auditory or visual data, we localize not auditory and visual Feel and images perception in the auditory or visual "field", and real phenomena reflected in our sensations, in perceptions in real space. Therefore, the localization of the sound source is determined not only by auditory, but also by visual perception in general, by the totality of all data that serve to orientate in real space.

HEARING THEORY

Of the large number of different theories of hearing, the strongest position is occupied by the resonance theory of hearing, put forward by G. Helmholtz.

According to this theory, the main organ of hearing is the cochlea, which functions as a set of resonators with which complex sounds can be decomposed into partial tones. Separate fibers of the main membrane are, as it were, strings tuned to different tones ranging from the lower to the upper limit of hearing. Helmholtz compared them to the strings of a musical instrument - a harp. The shorter fibers lying at the base of the cochlea should pick up high notes; the longer fibers located at its top are low. Since the fibers of the membrane are easily separated from each other in the transverse direction, they can easily oscillate in isolation. The number of these fibers ranges from 13-24 thousand; the number of auditory nerve endings is approximately 23,500. This is in good agreement with our auditory discrimination ability, which allows us to perceive thousands of steps of tones (about 11 octaves).

Helmholtz substantiated his resonant theory of hearing primarily with anatomical data. The anatomical structure of the vestibule is such that it is unlikely that the oscillations of the relymph can be transmitted not only to the cochlea, but also to the semicircular canals, since the vestibule is more or less completely separated by a septum. In addition, both ends of each semicircular canal open in the vestibule very close to each other; therefore, fluctuations of the membrane of the oval window can hardly involve the relymph of the canals in the fluctuation. Thus, the cochlea has to be recognized as the main organ of hearing.

In addition to anatomical data, the resonance theory is also confirmed by clinical observations. The phenomena called skipping of tones and islands of tones consist in the fact that in the first case the sensations of a larger or smaller area of tones drop out as if individual resonators were destroyed, or only small “islands” remain from the area of tones, i.e. the ability to hear sounds only of a certain pitch; disease of the apex of the cochlea entails deafness to the bass, that is, insensitivity to low tones, as if most of the resonators had been destroyed. Experiments by L. A. Andreev on the method of conditioned reflexes with animals whose cochlea was destroyed in a certain area also confirmed that "isolated damage to the organ of Corti, depending on the location of this damage, causes loss of hearing into individual tones."

Autopsy studies of damaged snails confirm that hearing loss for certain tones is always associated with degeneration of nerve fibers in the corresponding area of the underlying membrane. It was even possible to accurately localize individual tones. For example, a tone of 3192 Hz is localized approximately at a distance of 10-15 mm, a tone of 2048 Hz is located at a distance of 18.5-2.5 mm.

The Helmholtz theory is also supported by the Ouwer-Bray effect, or the snail effect, as well as the fact that damage, degeneration or absence of the organ of Corti, while maintaining other basic elements of the cochlea, causes a weakening or absence of the Ouver-Bray effect. The change in the threshold value of the electrical effect of the cochlea at its various points confirmed the picture of the distribution of the perception of tones along the main membrane outlined by Helmholtz (low tones are localized at the top of the cochlea, high tones are located at the base, near the round window, medium tones are in the region of the middle curl of the cochlea), etc.

Thus, numerous and weighty data testify in favor of Helmholtz's theory. Nevertheless, from the very beginning it also aroused serious objections. It is incomprehensible, firstly, why a membrane of insignificant size responds to a tone of a certain height with isolated vibrations of a single string or a narrow strip of these strings, especially since these strings are connected into a common membrane. However, the main difficulty for Helmholtz's theory is the explanation not of any particular issues, but of the perception of the totality of sounds, especially differences in a large range of sound strength. The range of loudness variation, in which several hundred gradations are observed, is very difficult to explain from the point of view of resonance theory. In fact, each nerve fiber can give the sensation of only one unchanging force. If the irritation is less than the threshold of sensitivity, then the nerve does not react at all. If it exceeds the threshold, then the strength of the nervous process is constant. The number of fibers affected by the action of one tone is calculated at a maximum of 1-2 tens. And it is not clear how this small number of fibers gives such a large number of gradations.

The binaural effect is also incomprehensible. Estimation of the difference in the time of arrival of the same phases of the wave to both ears can obviously occur only in the brain centers, which means that the periodic nature of the sound process must somehow be reflected in the nervous processes of the cortex. Meanwhile, the theory of Helmholtz, being the theory of the "peripheral analyzer", refers the assessment of sound exclusively to the excitation of nerves in this area of the cochlea.

Difficulties, which Helmholtz's theory is not yet able to explain, give rise to more and more new theories of hearing. One of these theories is the theory of G. Fletcher. According to this theory, it is not the individual strings of the main membrane that respond to sound waves, but the peri- and endolymph of the cochlea. The stirrup plate transmits sound vibrations of the cochlear fluid to the main membrane, and the maximum amplitude of these vibrations at higher tones lies closer to the base of the cochlea, at lower tones - closer to its top. Nerve fibers ending on the main membrane resonate only at frequencies above 60-80 Hz; there are no fibers that perceive lower frequencies on the main membrane. Nevertheless, a sense of height is formed in the mind up to 20 Hz. It arises as a combination tone of high harmonies. Thus, from the point of view of Fletcher's hypothesis, the perception of the pitch of low tones is explained by the perception of the entire complex of harmonic overtones, and not only by the perception of the frequency of the fundamental tone, as has usually been accepted until now. And since the composition of overtones largely depends on the strength of sounds, the close relationship between the three subjective qualities of sound becomes clear - its height, loudness and timbre. All these elements, each separately, depend on the frequency, and on the strength, and on the composition of the overtones of the sound.

According to Fletcher's hypothesis, resonant properties are inherent in the mechanical system of the cochlea as a whole, and not only in the fibers of the main membrane. Under the action of a certain tone, not only the fibers resonating at a given frequency vibrate, but the entire membrane and this or that mass of fluid of the cochlea. High tones lead to the movement of only a small mass of liquid near the base of the cochlea, low tones close closer to the helicotrema. Fletcher also overcomes the main difficulty of the resonance theory associated with the explanation of the large range of loudness. He believes that loudness is determined by the total number of nerve impulses coming to the brain from all excited nerve fibers of the main membrane.

Fletcher's theory in general does not deny the essence of the theory of H. Helmholtz and can be attributed to the theories of the "peripheral analyzer".

Another group of theories are the theories of the "central analyzer", or the so-called telephone theories. According to these theories, sound vibrations are converted by the cochlea into synchronous waves in the nerve and transmitted to the brain, where they are analyzed and perceived in pitch. This group of theories includes the theory of I. Ewald, according to which, under the action of sound, standing waves are formed in the cochlea with a length determined by the frequency of the sound. The pitch is determined by the perception of the shape of the standing wave pattern. The sensation of a certain tone corresponds to the excitation of one part of the nerve fibers; sensation of another tone - excitation of the other part. The analysis of sounds does not take place in the cochlea, but in the centers of the brain. Ewald managed to build a model of the main membrane, approximately the size of the real one. When it is excited by sound, the entire membrane comes into oscillatory motion; there is a "sound picture" in the form of standing waves with a shorter length, the higher the sound.

Despite successful explanations of some difficult details, Ewald's theory (as well as other theories of the "central analyzer") does not agree well with the latest physiological studies of the nature of nerve impulses. S. N. Rzhevkin, however, considers a dual point of view possible, namely, an explanation of the perception of high tones (which does not encounter difficulties) in the sense of the theory of the “peripheral analyzer”, and low ones - from the point of view of the “central analyzer”.

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