FEDERAL AGENCY FOR EDUCATION

State educational institution of higher professional education

AMUR STATE UNIVERSITY (GOUVPO "AmSU")

Department of Psychology and Pedagogy

on the topic: Types of sensations and their mechanisms

by discipline Sociology

Executor

group student

Supervisor

Blagoveshchensk

Introduction

1. General concept of sensation

2. Types of sensations and their mechanisms

2.1 Systematic classification of sensations

2.1.1 Exteroceptive sensations

2.1.1.1 Distant sensations

2.1.1.1.1 Visual sensations

2.1.1.1.2 Auditory sensations

2.1.1.1.3 Olfactory sensations

2.1.1.2 Contact sensations

2.1.1.2.1 Taste sensations

2.1.1.2.2 Temperature sensations

2.1.1.2.3 Sensations of touch, pressure

2.1.1.2.4 Tactile sensations

2.1.2 Interoceptive sensations

2.1.2.1 Organic sensations

2.1.2.2 Feelings of pain

2.1.3 Proprioceptive sensations

2.1.3.1 Feelings of balance

2.1.3.2 Motion sensations

2.2 Structural-genetic classification of sensations

2.2.1 Protopathic sensations

2.2.2 Epicritical sensations

Conclusion

Bibliographic list

INTRODUCTION

The main source of our knowledge about the external world and about our own body is sensations. They constitute the main channels through which information about the phenomena of the external world and the state of the body reaches the brain, giving a person the opportunity to navigate in the environment and in his body. If these channels were closed and the sense organs did not bring the necessary information, no conscious life would be possible.

Feelings in their quality and variety reflect the variety of properties of the environment for a person. The sense organs, or human analyzers, are adapted from birth for the perception and processing of various types of energy in the form of stimuli-stimuli (physical, chemical, mechanical and other influences).

Types of sensations reflect the uniqueness of the stimuli that generate them. These stimuli evoke corresponding sensations of different quality: visual, auditory, sensations of touch, pressure, pain, heat, cold, gustatory, olfactory, organic sensations, sensations of balance and movement.

1. GENERAL CONCEPT OF SENSATION

The simplest of cognitive mental processes is sensation. The process of sensation arises as a result of the impact on the sense organs of various material factors, which are called stimuli, the process of exposure itself is irritation. Irritation causes a process of excitation, which passes through the centripetal or afferent nerves to the cerebral cortex, where sensations arise. Thus, sensation is a sensory reflection of objective reality.

The essence of sensation is the reflection of the individual properties of the object. Each stimulus has its own characteristics, depending on which it can be perceived by certain sense organs. This is the process of reflecting the individual properties of the object.

The physiological basis of sensations is the activity of anatomical structures named by I.P. Pavlov's analyzers. Each analyzer consists of three parts: 1) a peripheral section called a receptor; 2) conducting nerve pathways; 3) the cortical sections of the analyzer, in which the processing of nerve impulses coming from the peripheral sections takes place. The cortical part of each analyzer includes an area that is a projection of the periphery (i.e., a projection of the sense organ) in the cerebral cortex, since certain parts of the cortex correspond to certain receptors. For the sensation to arise, it is necessary to use all the components of the analyzer. If any part of the analyzer is destroyed, the occurrence of the corresponding sensations becomes impossible.

The analyzer is an active organ that reflexively rebuilds itself under the influence of stimuli, so sensation is not a passive process, it always includes motor components. Numerous studies have found that sensation is closely related to movement, which sometimes manifests itself in the form of a vegetative reaction (vasoconstriction, galvanic skin reflex), sometimes in the form of muscle reactions (eye rotation, neck muscle tension). Thus, sensations are not passive processes at all - they are active, or reflex in nature.

Sensations are not only the source of our knowledge of the world, but also of our feelings and emotions. The simplest form of emotional experience is the so-called sensual, or emotional, tone of sensation, i.e. a feeling that is directly related to a feeling.

Feelings connect a person with the outside world and are both the main source of information about him and the main condition for mental development. However, despite the obviousness of these provisions, they have been repeatedly questioned. Representatives of the idealistic trend in philosophy and psychology expressed the idea that the true source of conscious activity is not sensations, but the internal state of consciousness, the ability of rational thinking, inherent in nature and independent of the influx of information coming from the outside world. These views formed the basis of the philosophy of rationalism. The bottom line was the assertion that consciousness and reason are the primary, inexplicable property of the human spirit. Idealist philosophers and many psychologists who are supporters of the idealistic concept have made attempts to reject the position that a person's sensations connect him with the external world, and to prove the opposite: sensations separate a person from the external world with an insurmountable wall. A similar position was put forward by D. Berkeley, D. Hume, E. Mach. These provisions lead to the following statement: a person cannot perceive the objective world, and the only reality is subjective processes that reflect the activity of his sense organs, which create subjectively perceived “elements of the world”. Opposite positions are taken by representatives of the materialistic trend, who consider it possible to objectively reflect the external world. In the process of historical development, especially perceiving organs were formed that specialized in reflecting special types of objectively existing forms of the movement of matter: auditory receptors that reflect sound vibrations; visual receptors that reflect certain ranges of electromagnetic oscillations, etc. The high specialization of various organs is based not only on the structural features of the peripheral part of the analyzer - receptors, but also on the highest specialization of neurons that are part of the central nervous apparatus, which receive signals perceived by peripheral sensory organs.

It should be noted that human sensations are a product of historical development, and therefore they are qualitatively different from the sensations of animals. In animals, the development of sensations is limited by biological, instinctive needs. In humans, on the contrary, the ability to feel is not limited by biological needs. Labor created for him a wider range of needs than for animals, and in activities aimed at satisfying these needs, human abilities, including the ability to feel, constantly developed. Therefore, a person can feel a much larger number of properties of the objects surrounding him than an animal.

2. TYPES OF SENSATIONS AND THEIR MECHANISMS

There are various approaches to the classification of sensations. It has long been customary to distinguish five (by the number of organs) of the main types of sensations, highlighting smell, taste, touch, hearing and vision. This classification of sensations according to the main "modalities" is correct, although not exhaustive. B.G. Ananiev spoke about eleven types of sensations. A.R. Luria believes that the classification can be carried out according to two main principles: systematic and genetic, in other words, according to the principle of modality, on the one hand, and according to the principle of complexity or level of their construction, on the other.

2.1 Systematic classification of sensations

Consider a systematic classification of sensations. This classification was proposed by the English physiologist C. Sherrington. Considering the largest and most significant groups of sensations, he divided them into three main types: interoceptive, proprioceptive and exteroceptive.

2.1.1 Exteroceptive sensations

The largest group of sensations are exteroceptive sensations. They bring information from the outside world to a person and are the main group of sensations that connects a person with the external environment. The whole group is conventionally divided into two subgroups: contact and distant.

2.1.1.1 Distant sensations

Distant sensations reflect the qualities of objects that are at some distance from the senses. These senses include hearing and sight. It should be noted that the sense of smell, according to many authors, occupies an intermediate position between contact and distant sensations, occupies an intermediate position, since olfactory sensations occur at a distance from the object, but at the same time, the molecules characterizing the smell of the object with which the olfactory receptor contacts undoubtedly belong to this subject. This is the duality of the position occupied by the sense of smell in the classification of sensations.

2.1.1.1.1 Visual sensations

The role of visual sensations in the knowledge of the world is especially great. They provide a person with rich and finely differentiated data of a huge range. Vision gives us the most perfect, genuine perception of objects. Visual sensations are most differentiated from affectivity; the moment of sensual contemplation is especially strong in them. Visual perceptions are objectified perceptions of a person. Therefore, they are of great importance for knowledge and for practical action.

The physiological basis of sensations is the activity of complex complexes of anatomical structures called analyzers. The concept of an analyzer (an apparatus that performs the function of distinguishing external stimuli) was introduced by Academician I.P. Pavlov. He also studied the structure of analyzers and came to the conclusion that they consist of three parts:

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

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

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

Sensation is a psychological process of reflection of individual saints and qualities of objects of the environment. peace.

They provide sensory knowledge of the world. More complex cognitive processes are based on the process of sensation. Sensations are constantly mediated by knowledge. Sensations reflect the objective qualities of objects (t°, taste, smell), their intensity and duration. Sensations provide the collection of sensory material, on the basis of which mental images are built.

1. exteroceptive (on the surface of the body) - visual, auditory, olfactory, gustatory and skin;

2. interoreceptive (in internal organs) - internal pain, vibration;

3. proprioceptive (in muscles, ligaments and tendons) - static, motor.

Perception is the mental process of reflecting the objects of the external world in a holistic way. It is caused by simultaneously acting complex stimuli, is carried out by the simultaneous and coordinated activity of several analyzers, and proceeds with the participation of the associative sections of the cerebral cortex and speech centers.

The process of forming a mental image during perception is a combination of recognition, understanding and comprehension, as well as assigning an object to a certain category. Perception is influenced by past experience, knowledge, attitudes. Perception is characterized by: 1) meaningfulness; 2) integrity; 3) structural (objectivity); 4) selectivity; 5) constancy; 6) apperception (past experience).

Perception and its impact on learning.

Perception, perception(from lat. perception) is a cognitive process that forms a subjective picture of the world. This is a mental process, which consists in the reflection of an object or phenomenon as a whole with its direct impact on the receptor surfaces of the sense organs. Perception is one of the biological mental functions that determine the complex process of receiving and converting information received with the help of the sense organs that form a subjective holistic image of an object that affects analyzers through a set of sensations initiated by this object. As a form of sensory reflection of an object, perception includes the detection of the object as a whole, the distinction of individual features in the object, the allocation of informative content in it that is adequate to the purpose of the action, the formation of a sensory image.

Perception is something much more than the transmission of neural impulses by the nervous system to certain areas of the brain. Perception also implies awareness by the subject of the very fact of stimulation and certain ideas about it, and in order for this to happen, it is first necessary to feel the “input” of sensory information, that is, to experience a sensation. In other words, perception is the process of comprehending the stimulation of sensory receptors. There is reason to look at perception as a task that consists of focusing on sensory input, analysis, and interpretation in order to create a meaningful representation of the world around us.

- Introduction -

All the information that a person uses in the process of cognition, he receives through sensory cognitive processes that arise during the direct interaction of the sense organs with environmental objects. Knowledge of the world begins with sensations. Feeling is the simplest cognitive process that ensures the functioning of all more complex processes. Sensations arise from the direct action of the properties and qualities of the external and internal environment on the sense organs. Information about the properties and qualities of objects and phenomena coming from the senses is reflected in our minds in the form of sensations and impressions.

Sensation is an elementary sensory cognitive process that reflects in the form of impressions the properties and qualities of objects that directly affect the senses. Sensation is a cognitive process, and impression is a form of reflection of the stimulus acting on the sense organs that has arisen in our mind. So, sensation is the process of transforming the information coming to the sense organs into facts of consciousness. This information exists in our minds in the form of various impressions: light, auditory, olfactory, gustatory and tactile.

Sensation, as such, is a rather complicated mental phenomenon, as it seems at first glance. Despite the fact that this is a fairly well-studied phenomenon, the global nature of its role in the psychology of activity and cognitive processes is underestimated by man. Sensations are widespread in ordinary human life, and in the continuous process of cognitive activity for people it is an ordinary primary form of the psychological connection of the organism with the environment.

Partial or complete absence of types of sensation (sight, hearing, taste, smell, touch) in a person prevents or hinders its development.
Sensations are of great importance for the formation of such cognitive processes as speech, thinking, imagination, memory, attention and perception, as well as for the development of activities as a specific type of human activity aimed at creating objects of material and spiritual culture, transforming one's abilities, preserving and improving nature, and the building of society.

An object research - human sensations.

Item research - types of sensations.

problem studies are different classifications of sensations in psychology.

Target work - to analyze the theoretical literature on the research problem, to consider various types and classifications of sensations.

Tasks:

1. Give a general concept of sensations in psychology.

2. Consider the properties and functions of sensations.

3. Consider the classification of types of sensations that exist in psychological science.

The work consists of an introduction, two chapters, an experimental part, a conclusion and a list of references.

The experimental part is devoted to visual sensations.

1. General concept of sensations and their functions in psychology

1.1 The concept of sensation

Sensations allow a person to perceive signals and reflect the properties and signs of things in the external world and the states of the body. They connect a person with the outside world and are both the main source of knowledge and the main condition for his mental development.

Sensation is one of the simplest cognitive mental processes. The human body receives a variety of information about the state of the external and internal environment in the form of sensations with the help of the senses. Sensation is the most important connection of a person with the surrounding reality.

The process of sensation arises as a result of the impact on the sense organs of various material factors, which are called stimuli, and the process of this impact itself is irritation.

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

There are two main forms of sensitivity, of which one depends on the environmental conditions and is called adaptation, and the other - on the conditions of the state of the organism, is called sensitization.

Adaptation (adaptation, adjustment) is a change in sensitivity in the process of adaptation to environmental conditions.

Three directions are distinguished:

1) increased sensitivity under the influence of a weak stimulus, for example, dark adaptation of the eye, when within 10-15 minutes. sensitivity increases by more than 200 thousand times (at first we do not see objects, but gradually we begin to distinguish their outlines);

2) a decrease in sensitivity under the influence of a strong stimulus, for example, for hearing, this occurs in 20-30 seconds; with continuous and prolonged exposure to the stimulus, the corresponding receptors adapt to it, as a result of which the intensity of nerve excitations transmitted from the receptors to the cortex begins to decrease, which underlies adaptation.

3) the complete disappearance of the sensation as a result of prolonged exposure to the stimulus, for example, after 1-1.5 minutes, the person stops feeling any smell in the room.

Adaptation is especially manifested in the field of vision, hearing, smell, touch, taste and indicates a greater plasticity of the organism, its adaptation to environmental conditions.

Sensitization is an exacerbation of sensitivity as a result of a change in the internal state of the body under the influence of stimuli that enter other sense organs at the same time (for example, an increase in visual acuity under the influence of weak auditory or olfactory stimuli).

1.2 Properties of sensations

All sensations can be characterized in terms of their properties. Moreover, the properties can be not only specific, but also common to all types of sensations. The main properties of sensations include: quality, intensity, duration and spatial localization, absolute and relative thresholds of sensations (Fig. 1).

Rice. 1. General properties of sensations

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.

The intensity of 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.

The duration of the sensation is the time 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) phase. 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 a certain inertia and does not disappear immediately after the cessation of the action of the stimulus that caused it. (C) Information published on the website
The trace from the stimulus remains in the form of a consistent image. Distinguish between positive and negative sequential images. A positive sequential image corresponds to the initial stimulus, consists in maintaining a trace of stimulus of the same quality as the current stimulus.

A negative sequential image consists in the appearance of a quality of sensation that is opposite to the quality of the irritant. (C) Information published on the website
For example, light-darkness, heaviness-lightness, heat-cold, etc. The appearance of negative sequential images is explained by a decrease in the sensitivity of this receptor to a certain effect.

And finally, sensations are characterized by the spatial localization of the stimulus. (C) Information published on the website
The analysis carried out by the receptors gives us information about the localization of the stimulus in space, i.e. we can tell where the light is coming from, where the heat is coming from, or what part of the body is affected by the stimulus.

All of the above properties, to one degree or another, reflect the qualitative characteristics of sensations. However, no less important are the quantitative parameters of the main characteristics of sensations - the degree (thresholds) of sensitivity (Fig. 2).

Rice. 2. Sensitivity thresholds

It should be remembered that the same stimulus for one person may be lower, and for another - above the threshold of sensation. The weaker the stimuli that a person is able to feel, the higher his sensitivity. In other words, the lower the absolute threshold of sensations, the higher the absolute sensitivity, and vice versa.

So, sensation is the simplest mental process of reflecting an individual quality (property) of an object with the direct impact of stimuli on the perceiving part of the analyzer.

1. 3 Physiological mechanisms of sensations

The physiological basis of sensations is the activity of complex complexes of anatomical structures called analyzers. The concept of an analyzer (an apparatus that performs the function of distinguishing external stimuli) was introduced by Academician I.P. Pavlov. He also studied the structure of analyzers and came to the conclusion that they consist of three parts:

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

2) conducting nerve pathways(afferent department - ᴨȇ transmits excitation to the central department; efferent department - it transmits a response from the center to ᴨȇriphery);

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

So, the organ of sensation is the central section of the analyzer.

For the sensation to arise, it is necessary to use all the components of the analyzer. If any part of the analyzer is destroyed, the occurrence of the corresponding sensations becomes impossible. So, visual sensations stop when the eyes are damaged, and when the integrity of the optic nerves is violated, and when the occipital lobes of both hemispheres are destroyed. In addition, for sensations to arise, 2 more conditions must be present:

Sources of irritation (irritants).

· Environment or energy, which is distributed in the environment from the source to the subject.

For example, there are no auditory sensations in a vacuum. In addition, the energy emitted by the source may be so small that a person does not feel it, but it can be registered by instruments. That. energy, in order to become tangible, must reach a certain value of the thresholds of the analyzer system.

Also, the subject may be awake or may be asleep. This should also be taken into account. In sleep, the thresholds of the analyzers are significantly increased.

So, sensation is a mental phenomenon, which is the result of the interaction of an energy source with the corresponding analyzer of a person. At the same time, we mean an elementary single source of energy that creates a homogeneous sensation (of light, sound, etc.).

5 conditions must exist for sensation to occur:

Receptors.

The analyzer core (in the cerebral cortex).

Conducting paths (with directions of impulse flows).

source of irritation.

Environment or energy (from source to subject).

It should be noted that human sensations are a product of historical development, and in this regard, they are qualitatively different from the sensations of animals. In animals, the development of sensations is entirely limited by their biological, instinctive needs. In humans, the ability to feel is not limited by biological needs. Labor created for him an incomparably wider range of needs than for animals, and in activities aimed at satisfying these needs, human abilities, including the ability to feel, constantly developed. In this regard, a person can feel a much larger number of properties of the objects surrounding him than an animal.

Sensations are not only the source of our knowledge of the world, but also of our feelings and emotions. The simplest form of emotional restraint is the so-called sensual, or emotional, tone of sensation, i.e. a feeling that is directly related to a feeling. For example, it is well known that certain colors, sounds, smells can by themselves, regardless of their meaning, memories and thoughts associated with them, cause us a pleasant or unpleasant feeling. The sound of a beautiful voice, the taste of orange, the smell of a rose are pleasant, have a positive emotional tone.
The creak of a knife on glass, the smell of hydrogen sulfide, the taste of cinchona are unpleasant, have a negative emotional tone.
This kind of simple emotional adjustments play a relatively insignificant role in the life of an adult, but from the point of view of the origin and development of emotions, their significance is very great.

Allocate the following functions of sensations.

Signaling - notification of the body about vital objects or properties of the surrounding world.

Reflective (figurative) - building a subjective image of the property necessary for orientation in the world.

Regulatory - adaptation in the outside world, regulation of behavior and activities.

There are several theories of sensation.

Receptive. According to this theory, the sense organ (receptor) passively responds to influencing stimuli. This passive response is the corresponding sensations, that is, sensation is a purely mechanical imprint of external influence in the corresponding sense organ. At present, this theory is recognized as untenable, since the active nature of sensations is denied.

Dialectical-materialistic.
According to this theory, “sensation is a real direct connection of consciousness with the external world, it is the transformation of the energy of external irritation into a fact of consciousness” (V. L. Lenin).

Reflex.
Within the framework of the reflex concept of I.M. Sechenov and I.P. Pavlov, studies were carried out that showed that, in terms of its physiological mechanisms, sensation is a holistic reflex that combines direct and feedback ᴨȇipheral and central sections of the analyzer.

Sensations begin to develop immediately after birth. However, not all types of sensitivity develop in the same way. Immediately after birth, the child develops tactile, gustatory and olfactory sensitivity (the child reacts to the temperature of the environment, touch, pain; determines the mother by the smell of mother's milk; distinguishes mother's milk from cow's milk or water). However, the development of these sensations continues for a long time (slightly developed at 4-5 years).

Less mature at the time of birth are visual and auditory sensations. Auditory sensations begin to develop faster (reacts to sound - in the first weeks of life, to direction - after two or three months, and to sound and music - in the third or fourth month). Speech hearing develops gradually. First, the child reacts to the intonation of speech (in the second month), then to the rhythm, and the ability to distinguish sounds (first vowels, and then consonants) appears by the end of the first year of life.

The absolute sensitivity to light in an infant is low, but increases markedly in the early days of life. Distinguishing colors occurs only in the fifth month.

In general, the absolute sensitivity of all species reaches a high level of development in the first year of life. Relative sensitivity develops more slowly (rapid development occurs at school age).

Feelings within certain limits can be developed by constant training. Thanks to the possibility of developing sensations, for example, children are taught (music, drawing).

Among violations of sensations, quantitative and qualitative changes are distinguished.

Quantitative disorders include: loss or decrease in the ability to feel various types of stimuli and an increase in this ability. Loss of sensitivity extends, as a rule, to tactile, pain, temperature sensitivity, but can cover all types of sensitivity.

This is usually associated with various diseases of the individual. Synesthesia is a quality sensory disorder. Another type of pathology of sensations is manifested in various, unpleasant sensations: numbness, tingling, burning, crawling, etc. With various pathological diseases, there may be changes in pain sensitivity. They consist in different pain sensitivity and endurance to pain.

Individual differences in sensations is a little studied area of ​​psychology. It is known that the sensitivity of different sense organs depends on many factors. Influence features of the central nervous system (in individuals with a strong nervous system, sensitivity is lower); emotionality (the emotional ones have a more developed sense of smell); age (hearing acuity is greatest at 13 years old, vision - at 20-30 years old, old people hear low-frequency sounds quite well, and high ones are worse); gender (women are more sensitive to high sounds, and men to low ones); the nature of the activity (steelworkers distinguish the subtlest shades of a hot metal stream, etc.).

2. Classification of types of sensations

There are various approaches to the classification of sensations. It has long been customary to distinguish five (according to the number of sensory organs) basic types of sensations: smell, taste, touch, sight and hearing. This classification of sensations according to the main modalities is correct, although not exhaustive. B.G. Ananiev spoke about eleven types of sensations. A.R. Luria believed that the classification of sensations can be carried out according to at least two basic principles - systematic and genetic (in other words, according to the principle of modality, on the one hand, and according to the principle of complexity or level of their construction, on the other).

Consider a systematic classification of sensations (Fig. 3). This classification was proposed by the English physiologist C. Sherrington. Considering the largest and most significant groups of sensations, he divided them into three main types: interoceptive, proprioceptive and exteroceptive sensations. The former combine signals that reach us from the internal environment of the body; the latter provide information about the position of the body in space and the position of the musculoskeletal system, provide regulation of our movements; finally, others provide signals from the outside world and create the basis for our conscious behavior. Consider the main types of sensations separately.

The basis of perception are exteroreceptors, because they provide an objective view of the outside world.

As you know, a person has five senses. There are one more types of external sensations, since motor skills do not have a separate sense organ, but they also cause sensations. Therefore, a person can experience six types of external sensations: visual, auditory, olfactory, tactile (tactile), gustatory and kinesthetic sensations.

Rice. 3. Systematic classification of the main types of sensations The main source of information about the outside world is the visual analyzer. With its help, a person receives up to 80% of the total amount of information. The organ of visual sensations is the eye. At the level of sensations, he perceives information about light and color. Colors perceived by a person are divided into chromatic and achromatic. The colors that make up the spectrum of the rainbow (that is, the splitting of light - the well-known "Every hunter wants to know where the pheasant is sitting") belong to the first ones. To the second - black, white and gray colors. Color shades, containing about 150 smooth transitions from one to another, are perceived by the eye depending on the parameters of the light wave. Visual sensations have a great influence on a person. All warm colors have a positive effect on a person's performance, excite him and cause a good mood. Cool colors calm a person. Dark colors have a depressing effect on the psyche. Colors can carry warning information: red indicates danger, yellow warns, green indicates safety, etc. The auditory analyzer is next in importance in obtaining information. Sensations of sounds are usually divided into musical and noise. Their difference lies in the fact that musical sounds are created by periodic rhythmic vibrations of sound waves, and noises are created by non-rhythmic and irregular vibrations. Auditory sensations are also of great importance in human life. The source of auditory sensations is a variety of sounds acting on the organ of hearing. Auditory sensations reflect noise, musical and speech sounds. Sensations of noise and rustle signal the presence of objects and phenomena that emit sounds, their location, approach or removal. They can warn of danger and cause a certain emotional relaxation. Musical sensations are characterized by an emotional tone and melody. These sensations are formed in a person on the basis of the upbringing and development of musical ear and are associated with the general musical culture of human society. Speech sensations are the sensual basis of human speech activity. On the basis of speech sensations, phonemic hearing is formed, thanks to which a person can distinguish and pronounce the sounds of speech. Phonemic hearing has an impact not only on the development of oral and written speech, but also on mastering a foreign language. Many people have an interesting feature - a combination of sound and visual sensations into one general sensation. In psychology, this phenomenon is called synesthesia. These are stable associations that arise between the objects of auditory perception, such as melodies, and color sensations. Often people can tell "what color" a given melody or word is. Slightly less common is synesthesia based on the association of color and smell. It is often inherent in people with a developed sense of smell. Such people can be found among tasters of perfumery products - not only a developed olfactory analyzer is important for them, but also synesthetic associations that allow the complex language of smells to be translated into a more universal language of color. In general, the olfactory analyzer, unfortunately, most often people are not very well developed. People like the hero of Patrick Suskind's novel "Perfume" are rare and unique phenomena. This is one of the most ancient, simple, but vital sensations. Anatomically, the organ of smell is located in most living beings in the most advantageous place - in the middle, in the prominent part of the body. The path of the olfactory receptors to those brain structures where the impulses received from them are received and processed is the shortest. Nerve fibers extending from the olfactory receptors directly without intermediate switches enter the brain. The part of the brain called the olfactory is also the most ancient, and the lower the living being is on the evolutionary ladder, the more space in the mass of the brain it occupies. In fish, for example, the olfactory brain covers almost the entire surface of the hemispheres, in dogs - about one third of it, in humans, its relative share in the volume of all brain structures is approximately one twentieth. this kind of sensations has for living beings. For some animal species, the meaning of smell goes beyond the perception of smells. In insects and higher apes, the sense of smell also serves as a means of intraspecific communication. The odor classification system, known as the Hanning Prism (floral, fruity, spicy, resinous, burnt, putrid), forms the corners of a prism with intermediate qualities located on planes (Fig. 4 ).Rice. 4. "Hanning Prism" There are other classifications. In practice, a comparison of this smell with a known standard (lilac, hay, etc.) is often used. Taste sensations are a reflection of the quality of food, providing the individual with information about whether this substance can be ingested. Taste sensations (often together with smell) are caused by the action of the chemical properties of substances dissolved in saliva or water on taste buds (taste buds) located on the surface of the tongue, back of the throat, palate and epiglottis. The taste classification system is represented by "Henning's Tetrahedron" ( Fig. 5), in which there are four main tastes (sweet, sour, salty, bitter). 5. "Hanning's Tetrahedron" They are located at the corners of the tetrahedron (four-cornered pyramid), and all other taste sensations are located on the planes of the Tetrahedron and represent them as combinations of two or more basic taste sensations. Skin sensitivity, or touch, is the most widely represented and widespread kind of sensitivity. We all know the sensation that occurs when an object touches the surface of the skin, is not an elementary tactile sensation. It is the result of a complex combination of four other, simpler types of sensations: pressure, pain, heat and cold, and for each of them there is a specific type of receptors unevenly located in different parts of the skin surface. The presence of such receptors can be found in almost all parts of the skin. However, the socialization of skin receptors has not yet been accurately established. It is not clear whether there are receptors exclusively intended for the perception of one impact, generating differentiated sensations of pressure, pain, cold or heat, or the quality of the resulting sensation may vary depending on the state of the same receptor, as well as on the specifics of the property acting on it. It is only known that the strength and quality of skin sensations are themselves relative. For example, with simultaneous exposure to the surface of one area of ​​the skin with warm water, its temperature is perceived differently depending on what kind of water we are acting on the neighboring area of ​​the skin. If it is cold, then there is a feeling of warmth on the first part of the skin, if it is hot, then a feeling of cold. Temperature receptors, as a rule, have two threshold values: they respond to high and low impacts, but do not respond to medium ones. Using the examples of kinesthetic sensations and sensations of balance, one can confirm the fact that not all sensations are conscious. In everyday speech, which we use, there is no word for sensations coming, for example, from receptors located in muscles and working when they contract or stretch. Nevertheless, these sensations still exist, providing control of movements, an assessment of the direction and speed of movement, and the magnitude of the distance. They are formed automatically, enter the brain and regulate movements at a subconscious level. To designate them in science, a word is adopted that comes from the concept of "movement" - kinetics, and in this regard they are called kinesthetic. Without sensations of this kind, we would experience great difficulties associated with the simultaneous coordination of movements of various parts of the body, maintaining posture, balance, control of various involuntary movements (unconditioned reflex reactions, skills, etc.), because they all include such motor moments that are performed automatically and very quickly. In addition to muscles, receptors for kinesthetic sensations are located in other organs. For example, the formation of sensations that contribute to maintaining and maintaining balance occurs due to the presence of special balance receptors present in the inner ear. The feeling of acceleration or deceleration of movements depends on the work of these receptors. There is evidence that, with the help of ordinary sense organs, a person perceives stimuli that are below the lower threshold of his sensitivity. These stimuli (they are called subsensory) are able to influence even conscious sensations. This proves the existence of human susceptibility to imperceptible conscious stimuli. With the help of this sensitivity, we refine, for example, the localization of sound. Physiologist G.V. Gershuni, in particular, writes that “immediately after a contusion, when auditory sensations are either completely absent or appear only when exposed to very strong sounds, such body responses arise as a change in the spontaneous electrical activity of the cerebral cortex - the appearance of rhythms of higher frequencies ... a change in the potential difference of the skin (galvanic skin reaction) and a cochlear-pupillary reflex - a change in the diameter of the pupil under the action of sound ". The zone of inaudible sounds that cause the cochlear-pupillary reflex was called Gershuni" subsensory area ". At the stages of gradual restoration of hearing, this zone increases, and with complete normalization it decreases. Other involuntary reactions recorded in the course of the pathological process behave in a similar way. Normally, the limits of the subsensory area significantly depend on the state of the person and for the cochlear-pupillary reflex range from 5 to 12 dB. The entire group of exteroceptive sensations is conventionally divided into two subgroups: contact and distant sensations. Contact sensations are caused by the direct impact of the object on the sense organs. Taste and touch are examples of contact sensations. Distant sensations reflect the qualities of objects that are at some distance from the senses. These senses include hearing and sight. It should be noted that the sense of smell, according to many authors, occupies an intermediate position between contact and distant sensations, since formally olfactory sensations occur at a distance from the object, but at the same time, the molecules that characterize the smell of the object, with which the olfactory receptor contacts, undoubtedly belong to this subject. This is the duality of the position occupied by the sense of smell in the classification of sensations. Since sensation arises as a result of the action of a certain physical stimulus on the corresponding receptor, the primary classification of sensations considered by us naturally proceeds from the type of receptor that gives the sensation of a given quality, or " modality.” However, there are sensations that cannot be associated with any particular modality. Such sensations are called intermodal. These include, for example, vibration sensitivity, which connects the tactile-motor sphere with the auditory one. Vibration sensation is sensitivity to vibrations caused by a moving body. According to most researchers, the vibrational sense is an intermediate, transient form between tactile and auditory sensitivity. In particular, some authors believe that tactile-vibrational sensitivity is one of the forms of sound perception. With normal hearing, it does not particularly protrude, but with damage to the auditory organ, this function of it is clearly manifested. Vibration sensitivity is of particular practical importance in visual and hearing impairments. It plays an important role in the lives of deaf and deaf-blind people. The deaf-blind, due to the high development of vibration sensitivity, learned about the approach of a truck and other modes of transport at a great distance. In the same way, through a vibrational sense, the deaf-blind and dumb learn when someone enters their room. Therefore, sensations, being the simplest type of mental processes, are actually very complex and not fully understood. us from the internal environment of the body, sensitivity to our own metabolic processes (hunger, thirst, suffocation, etc. ). Usually they close at the subsensory (unconscious) subcortical level and are realized only in the event of a significant violation of the normal state of the body, violation of the necessary constancy of its internal environment (homeostasis). They arise due to receptors located on the walls of the stomach and intestines, the heart and the circulatory system and other internal organs. Interoceptive sensations are among the least conscious and most diffuse forms of sensations and always retain their proximity to emotional states. It should also be noted that interoceptive sensations are often called organic. Proprioceptive sensations (“deep sensitivity”) are sensations that convey information about the position of the body in space and the position of the musculoskeletal system, provide the regulation of our movements. These sensations form the basis of human movements, playing a decisive role in their regulation. This group of sensations includes a sense of balance, or static sensation, as well as a motor, or kinesthetic, sensation. Peripheral receptors for this sensitivity are found in muscles and joints (tendons, ligaments) and are called Paccini bodies. Peripheral receptors for the sensation of balance are located in the semicircular canals of the inner ear. It should be noted that there are other approaches to the classification of sensations. An attempt to create a genetic classification of sensations was made by the English neurologist X. Head, who singled out the more ancient - protopathic and younger - epicritical sensitivity. Protopathic sensations (Greek protos - ᴨȇrvy, ᴨȇprimary, pathos - illness, suffering) - phylogenetically these are more ancient sensations, primitive and undifferentiated, mixed with emotions and localized. More often this concept is used in relation to skin sensitivity. This includes organic sensations (hunger, thirst, etc.). Epicritical sensations (Greek Epikrisis - judgment, decision) - phylogenetically new sensations. They are characterized by a lower threshold of irritation, the ability to feel light touches, accurate localization of external irritation, and more perfect recognition of the quality of an external stimulus. (C) Information published on the website
These include all the main types of human sensations. Types of sensations are classified according to modality, the location of the receptors, and contact with the stimulus. - Conclusion -

The vital role of sensations is to promptly and quickly bring to the central nervous system, as the main control organ of activity, information about the state of the external and internal environment, the presence of biologically significant factors in it.

The life of every person is complex and multifaceted. It is revealed through a number of important processes. They can be conditionally divided into social and business activity of an individual, culture, medicine, sports, communication, interpersonal relations, scientific and research activities, entertainment and recreation.

The full flow of all the above processes is problematic, and sometimes even impossible to imagine without the involvement of all our senses. In this regard, it is necessary to evaluate the role of sensations in a person's life, since sometimes this knowledge helps in organizing the successful existence of an individual in society, achieving success in a business environment.

So, sensation is a process of reflecting the individual properties of objects of the objective world, both the external environment and one's own organism, arising from their direct impact on receptors (sense organs). This is a process of primary information processing, which is characteristic of both animals and humans. With the help of sensations, the subject reflects light, color, sounds, noises, heat, cold, smells, tastes. Sensations are a prerequisite for the creation of images and their knowledge.

There are several classifications of types of sensations. By modality (types of analyzers), sensations are distinguished: visual, auditory, tactile (tactile, temperature and pain), olfactory and gustatory. There are also intermodal sensations.

According to the nature of the reflection and the location of the receptors, the classification of sensations was presented by the English physiologist C. Sherrington. Based on the anatomical location of the receptors, sensations are divided into three classes: interoceptive (receptors are located in the internal environment of the body), proprioceptive (receptors are located in the muscles, tendons and joint capsules) and exteroceptive (receptors are located on the surface of the body). Exteroceptive include: contact (taste, touch) and distant (smell, hearing, vision). A.R. Luria completes the final row with two categories: intermodal (intermediate) and non-digital types of sensations.

By origin (X. Head's genetic classification), they distinguish: protopathic and epicritical sensations.

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Physiological mechanisms of sensation

The physiological basis of sensations is the activity of complex complexes of anatomical structures, called Pavlov analyzers, each analyzer consists of 3 parts.

1. peripheral department - receptors. The receptor is the perceiving part of the analyzer, its main function is to transform external energy into a nerve impulse.

2. conductive nerve pathways - (centripetal, centrifugal, afferent)

3. cortical sections of the analyzer, in which the processing of nerve impulses coming from the peripheral sections takes place. For the sensation to arise, it is necessary to use all the components of the analyzer. If any part of the analyzer is destroyed, the occurrence of sensation becomes impossible (visual sensation stops when the eye is damaged.). The analyzer is an active organ that reflexively rebuilds under the influence of stimuli, so sensation is not a passive process, but always includes motor components. Thus, the American psychologist D. Neff, observing skin areas with a microscope, made sure that when they are irritated with a needle, the moment the sensation occurs is accompanied by a reflex-motor reaction of this skin area.

Classification of sensations

Depending on which organ perceives the action of the stimulus, from which side the receptors are affected, what is the quality of the stimulus itself - the classification of sensations depends on all this. A.R. Luria believes that the classification of sensations can be carried out according to at least two main principles: systematic and genetic.

Since a sensation arises as a result of the action of a certain physical stimulus on the corresponding receptor, the primary classification of sensations naturally proceeds from the receptor that gives sensations of a given quality or "modality".

As the main types of sensations, skin sensations are distinguished - touch and pressure, touch, temperature sensations and pain, taste and olfactory sensations, visual, auditory, sensations of position and movement (static and kinesthetic) and organic sensations (hunger, thirst, sexual sensations, pain , sensations of internal organs, etc.).

Various modalities of sensations, so sharply differentiated from each other, have developed in the process of evolution. And to the present, there are still far from sufficiently studied intermodal types of sensitivity. Such, for example, is vibration sensitivity, which connects the tactile-motor sphere with the auditory one and, in genetic terms (according to a number of authors, starting with Charles Darwin), is a transitional form from tactile sensations to auditory ones.

Vibrational feeling is the sensitivity to vibrations in the air caused by a moving body. The physiological mechanism of vibration sensitivity has not yet been elucidated. According to some researchers, it is due to the bones, but not the skin (M. von Freud and others); others consider vibration sensitivity to be tactile-skin, recognizing bones as a resonator-physical function only (V.M. Bekhterev, L.S. Frey, etc.). Vibrational feeling is an intermediate, transitional form between tactile and auditory sensitivity. Some researchers (D. Katz and others) include it in tactile sensitivity, distinguishing, however, the vibrational feeling from the feeling of pressure; others bring it closer to the auditory. In particular, the school of L.E. Komendantova believes that tactile-vibrational sensitivity is one of the forms of sound perception.

Vibration sensitivity acquires special practical significance in case of visual and hearing impairments. It plays an important role in the lives of deaf and deaf-blind people. The deaf-blind, due to the high development of vibration sensitivity, recognized the approach of trucks and other modes of transport at a long distance. In the same way, through the vibrational sense, deaf-blind people know when someone enters their room.

In some cases, the development of vibrational sensitivity, and especially the ability to use it, reaches such perfection that it allows the deaf-blind-mute to catch the rhythm of music, which took place with Helen Keller.

Proceeding specifically from the properties of stimuli, a distinction is made between mechanical sensitivity, including tactile sensations, kinesthetic, etc.; close to it acoustic, due to vibrations of a solid body; chemical, which includes smell and taste; thermal and optical.

All receptors are divided into three groups according to their location: interoceptors, proprioceptors and exteroceptors (Sherrington proposed a classification); respectively, intero-, proprio- and exteroceptive sensitivity are distinguished.

In the genetic plan, another classification of types of sensitivity is put forward, which is of significant interest. It proceeds from the rate of regeneration of afferent fibers after transection of a peripheral nerve, which H. Head observed in experiments he performed on himself.

Interpreting his observations about the successive restoration of sensitivity after nerve transection, Head comes to recognize two different types of sensitivity - protopathic and epicritical. Protopathic sensitivity is more primitive and affective, less differentiated and localized. The epicritical sensibility is more subtly differentiating, objectified and rational; the second controls the first. For each of them, there are special nerve fibers that regenerate at different rates. Head considers the fibers conducting protopathic sensitivity to be phylogenetically older, primitive in structure and therefore recovering earlier, while epicritical sensitivity is carried out by fibers of a phylogenetically younger system and more complexly built. Head believes that not only the afferent pathways, but also the central formations of protopathic and epicritical sensitivity are different: the higher centers of protopathic sensitivity are localized, according to Head, in the thalamus, and epicritical sensitivity - in phylogenetically later cortical formations. Under normal conditions, protopathic sensitivity is controlled by epicritical through the inhibitory effect of the cortex on the thalamus and underlying areas with which protopathic sensitivity is associated.

With all the interest that Head's theory arouses, it is still only a hypothesis and, moreover, a hypothesis that is disputed by some.

In this matter, it is necessary to dissect two sides: firstly, the question of the legitimacy of opposing two types of sensitivity as genetically consecutive steps, each having a special type of afferent fibers, and, secondly, the question of the existence of functional differences between certain types of normal sensitivity, expressed in the more affective, less differentiated character of one and the more perceptual, differentiated, rational character of the other.

Leaving open the first question, which relates to the specific core of Head's teaching, the answer to the second can be considered indisputable. In order to be convinced of this, it is enough to take, for example, organic sensitivity, which, for the most part, provides us with sensations that are difficult to localize, blurred, difficult to differentiate, with such a bright affective coloring that each such sensation (hunger, thirst, etc.) is interpreted just like feeling. Their cognitive level, the degree of differentiation of subjective-affective and objective-objective moments in them differ significantly.

Each sensation, being an organic process reflecting reality, inevitably includes polarity, two-sidedness. On the one hand, it reflects some side of the reality that acts on the receptor as an irritant, on the other hand, it reflects the state of the organism to some extent. This is connected with the presence in sensitivity, in sensory, on the one hand, affective, on the other - perceptual, contemplative moments. Both of these sides are presented in sensations in unity. But in this unity usually one side to a greater or lesser extent suppresses the other. In some cases, in sensory, affective character predominates to one degree or another, in another, perceptual character, the first predominantly in those types of sensitivity that serve mainly to regulate the internal relationships of the organism; the second - in those that primarily regulate its relationship with the environment.

The more primitive sensitivity was, apparently, initially an unsplit, undifferentiated unity of perceptual, affective and motor moments, reflecting the undivided properties of the object and the state of the subject. In the future, the development of sensitivity goes in different directions; on the one hand, the types of sensitivity associated with the regulation of internal relationships retain an affective character; on the other hand, in the interests of correct adaptation, and then the impact on the environment, it is necessary to display things in their objective properties, independent of the subject. Therefore, in the process of biological evolution, more and more specialized, relatively closed apparatuses began to form, which thus turned out to be more and more adapted to expressing not the general state of the organism, but reflecting, as impersonally and objectively as possible, the properties of things themselves.

In physiological terms, this is due to the fact that peripheral irritation in itself does not unambiguously determine sensation, but is only the initial phase of the process, which includes higher centers. Moreover, as the central apparatus of the cortex develops, centrifugal innervations (going from the center to the periphery), according to the latest data, apparently play an almost as significant role in the activity of sensory systems as centripetal (going from the periphery to the center). This regulation of the activity of individual sensory systems by central factors rationalizes sensitivity and ultimately serves to correct local irritation, as it were, to bring sensory qualities in consciousness into maximum correspondence with the object.

The problem of sensitivity was developed initially in terms of psychophysiology, which was essentially a part of physiology. Only recently has it risen in its own psychological plane. In psychophysiology, sensations are considered only as an indicator of the state of an organ. Actually, the psychological study of sensations begins where sensations are considered not only as indicators of the state of an organ, but as reflections of the properties of perceived objects. In this relationship to the object, they are at the same time a manifestation of the subject, the individual, his attitudes, needs, his history, and not just the reactions of the organ. Human psychology studies the sensitivity of a person, and not the activity of the sense organs themselves. Moreover, any specific process of sensation is carried out by a specific individual and depends on his individual characteristics, more directly - on his susceptibility and impressionability, i.e. characteristics of his temperament.

Turning to the study of sensation, we will go from less differentiated and objectified interoceptive sensations and proprioceptive to more differentiated and objectified exteroceptive and from contact receptors to distant receptors.

This order of presentation, in which interoception precedes exteroception, does not in any way imply any genetic priority of the former over the latter. Apparently, genetically primary was the reception, in which the exteroceptive and interoceptive moments were not yet dissected; while the main value belonged to the exteroceptive components.

A brief digression into the development of the concept of sensations

Feel- “the law of the specific energy of the sense organ”, that is, sensation does not depend on the nature of the stimulus, but on the organ or nerve in which the process of irritation occurs. The eye sees, the ear hears. The eye cannot see, but the ear cannot see. 1827

The objective world is fundamentally unknowable. The result of the sensation process is a partial, that is, a partial image of the world. All that we perceive is the process of specific impact on the senses. "Mental processes" Vecker L.M.

Power dependence of the change in sensations with a change in the intensity of stimuli (Stevens law)

The lower and upper absolute thresholds of sensations (absolute sensitivity) and the thresholds of discrimination (relative sensitivity) characterize the limits of human sensitivity. In addition to this, there are operational thresholds of sensations— the magnitude of the difference between the signals, at which the accuracy and speed of their discrimination reach a maximum. (This value is an order of magnitude greater than the difference threshold value.)

2. Adaptation. The sensitivity of the analyzer is not stable, it changes depending on various conditions.

So, entering a poorly lit room, at first we do not distinguish objects, but gradually the sensitivity of the analyzer increases; being in a room with any smells, after a while we stop noticing these smells (the sensitivity of the analyzer decreases); when we get from a poorly lit space into a brightly lit one, the sensitivity of the visual analyzer gradually decreases.

A change in the sensitivity of the analyzer as a result of its adaptation to the strength and duration of the acting stimulus is called adaptation(from lat. adaptatio- fixture).

Different analyzers have different speed and range of adaptation. To some stimuli, adaptation occurs quickly, to others - more slowly. Olfactory and tactile adapt faster (from the Greek. taktilos- touch) analyzers. Auditory, gustatory and visual analyzers adapt more slowly.

Full adaptation to the smell of iodine occurs in a minute. After three seconds, the sensation of pressure reflects only 1/5 of the strength of the stimulus. (Searching for glasses shifted to the forehead is one example of tactile adaptation.) Full dark adaptation of the visual analyzer takes 45 minutes. However, visual sensitivity has the largest range of adaptation - it changes 200,000 times.

The phenomenon of adaptation has expedient biological significance. It contributes to the reflection of weak stimuli and protects the analyzers from excessive exposure to strong ones. Adaptation, like getting used to constant conditions, provides an increased orientation to all new influences. Sensitivity depends not only on the strength of the impact of external stimuli, but also on internal states.

3. Sensitization. Increasing the sensitivity of analyzers under the influence of internal (mental) factors is called sensitization(from lat. sensibilis- sensitive). It can be caused by: 1) the interaction of sensations (for example, weak taste sensations increase visual sensitivity. This is due to the interconnection of analyzers, their systemic work); 2) physiological factors (the state of the body, the introduction of certain substances into the body; for example, vitamin A is essential to increase visual sensitivity); 3) the expectation of a particular impact, its significance, a special setting to distinguish between stimuli; 4) exercise, experience (thus, tasters, by specially exercising taste and olfactory sensitivity, distinguish between various varieties of wines, teas and can even determine when and where the product was made).

In people deprived of any kind of sensitivity, this deficiency is compensated (compensated) by increasing the sensitivity of other organs (for example, increased auditory and olfactory sensitivity in the blind). This so-called compensatory sensitization.

Strong excitation of some analyzers always lowers the sensitivity of others. This phenomenon is called desensitization. So, the increased noise level in "loud shops" lowers visual sensitivity; visual desensitization occurs.

Rice. 4. . The inner squares produce sensations of varying intensities of gray. In reality they are the same. Sensitivity to the properties of phenomena depends on adjacent and successive contrast effects.

4. . One of the manifestations of the interaction of sensations is their contrast(from lat. contraste- a sharp contrast) - an increase in sensitivity to one property under the influence of other, opposite, properties of reality. So, the same gray figure appears dark on a white background, and white on a black one (Fig. 4).

5. Synesthesia. An associative (phantom) non-modal sensation that accompanies a real one (the sight of a lemon causes a sensation of sourness) is called synesthesia(from Greek. synaisthesis shared feeling).

Rice. 5.

Features of certain types of sensations.

visual sensations. The colors perceived by a person are divided into chromatic (from the Greek. chroma- color) and achromatic - colorless (black, white and intermediate shades of gray).

For the appearance of visual sensations, the impact of electromagnetic waves on the visual receptor, the retina of the eye (an accumulation of photosensitive nerve cells located at the bottom of the eyeball), is necessary. In the central part of the retina, nerve cells predominate - cones, which provide a sense of color. At the edges of the retina, rods sensitive to brightness changes predominate (Fig. 5, 6).

Rice. 6. . To light-sensitive receptors - rods (reacting to changes in brightness) and cones (reacting to different wavelengths of electromagnetic waves, i.e. to chromatic (color) influences), light penetrates, bypassing ganglion and bipolar cells, which carry out the primary elementary analysis of nerve impulses going already from the retina. For the occurrence of visual excitation, it is necessary that the electromagnetic energy that enters the retina be absorbed by its visual pigment: rod pigment - rhodopsin and cone pigment - iodopsin. Photochemical transformations in these pigments give rise to the visual process. At all levels of the visual system, this process: manifests itself in the form of electrical potentials, which are recorded by special devices -, electroretinograph,.

Light (electromagnetic) beams of different lengths cause different color sensations. Color - a mental phenomenon - human sensations caused by different frequencies of electromagnetic radiation (Fig. 7). The eye is sensitive to the part of the electromagnetic spectrum from 380 to 780 nm (Fig. 8). The wavelength of 680 nm gives the impression of red; 580 - yellow; 520 - green; 430 - blue; 390 - purple flowers.

electromagnetic radiation.

Rice. 7. electromagnetic spectrum and its visible part (NM - nanometer - one billionth of a meter)

Rice. 8. .

Rice. 9. . Opposite colors are called complementary colors - when mixed, they form white. Any color can be obtained by mixing two border colors with it. For example: red - a mixture of orange and purple).

The mixture of all perceived electromagnetic waves gives the sensation of white.

There is a three-component theory of color vision, according to which the whole variety of color sensations arises as a result of the work of only three color-perceived receptors - red, green and blue. Cones are divided into groups of these three colors. Depending on the degree of excitation of these color receptors, various color sensations arise. If all three receptors are excited to the same extent, then there is a sensation of white color.

Rice. 10. .

To different parts of the electromagnetic spectrum, our eye has unequal sensitivity. It is most sensitive to light rays with a wavelength of 555 - 565 nm (light green color tone). The sensitivity of the visual analyzer at dusk moves towards shorter wavelengths - 500 nm (blue color). These rays begin to appear lighter (Purkinje phenomenon). The rod apparatus is more sensitive to ultraviolet color.

In conditions of sufficiently bright lighting, the cones turn on, the rod apparatus turns off. In low light, only sticks are included in the work. Therefore, in twilight lighting, we do not distinguish the chromatic color, the color of objects.

Rice. eleven. . Information about events in the right half of the visual field enters the left occipital lobe from the left side of each retina; information about the right half of the visual field is sent to the left occipital lobe from the right parts of both retinas. The redistribution of information from each eye occurs as a result of the crossing of part of the optic nerve fibers in the chiasm.

Visual excitations are characterized by some inertia. This is the reason for the preservation of a trace of light irritation after the cessation of exposure to the stimulus. (Therefore, we do not notice gaps between frames of the film, which turn out to be filled with traces from the previous frame.)

People with weakened cone apparatus have difficulty distinguishing chromatic colors. (This drawback, described by the English physicist D. Dalton, is called color blind). The weakening of the rod apparatus makes it difficult to see objects in twilight lighting (this drawback is called "night blindness".)

For the visual analyzer, the difference in brightness is essential - contrast. The visual analyzer is capable of distinguishing contrast within certain limits (optimum 1:30). Strengthening and weakening of contrasts is possible through the use of various means. (To reveal a subtle relief, shadow contrast is enhanced by side lighting, the use of filters.)

The color of each object is characterized by those rays of the light spectrum that the object reflects. (A red object, for example, absorbs all rays of the light spectrum, except for the red, which is reflected by it.) The color of transparent objects is characterized by the rays that they transmit. Thus, The color of any object depends on which rays it reflects, absorbs and transmits..

Rice. 12.: 1 - chiasm; 2 - visual tubercle; 3 - occipital lobe of the cerebral cortex.

In most cases, objects reflect electromagnetic waves of various lengths. But the visual analyzer perceives them not separately, but in total. For example, exposure to red and yellow colors is perceived as orange, and a mixture of colors occurs.

Signals from photoreceptors - light-sensitive formations (130 million cones and rods) go to 1 million larger (ganglion) retinal neurons. Each ganglion cell sends its own process (axon) to the optic nerve. Impulses traveling to the brain along the optic nerve receive primary processing in the diencephalon. Here, the contrast characteristics of the signals and their temporal sequence are enhanced. And from here, nerve impulses enter the primary visual cortex, localized in the occipital region of the cerebral hemispheres (fields 17-19 according to Brodmann) (Fig. 11, 12). Here, individual elements of the visual image are distinguished - points, angles, lines, directions of these lines. (Established by Boston researchers, 1981 Nobel Prize winners Hubel and Wiesel.)

Rice. 13. optogram taken from the retina of a dog's eye after her death. This indicates the screen principle of functioning of the retina.

The visual image is formed in the secondary visual cortex, where the sensory material is compared (associated) with previously formed visual standards - the image of the object is recognized. (It takes 0.2 seconds from the beginning of the stimulus to the appearance of a visual image.) However, a screen display of the perceived object occurs already at the level of the retina (Fig. 13).

auditory sensations. There is an opinion that we receive 90% of information about the world around us through vision. It can hardly be calculated. After all, what we see with the eye should be covered by our conceptual system, which is formed integratively, as a synthesis of all sensory activity.

Rice. 14. Deviations from normal vision - nearsightedness and farsightedness. These deviations can usually be compensated for with glasses with specially selected lenses.

The work of the auditory analyzer is no less complex and important than the work of the visual analyzer. This channel is the main flow of speech information. A person feels sound 35 - 175 ms after he has reached the auricle. Another 200 - 500 ms is necessary for maximum sensitivity to a given sound. It also takes time to turn the head and properly orient the auricle in relation to the source of a weak sound.

From the tragus of the auricle, the oval auditory canal deepens into the temporal bone (its length is 2.7 cm). Already in the oval passage, the sound is significantly amplified (due to the resonant properties). The oval passage is closed by the tympanic membrane (its thickness is 0.1 mm, and its length is 1 cm), which constantly vibrates under the influence of sound influences. The tympanic membrane separates the outer ear from the middle ear - a small chamber with a volume of 1 cm³ (Fig. 15).

The middle ear cavity is connected to the inner ear and the nasopharynx. (The air coming from the nasopharynx balances the external and internal pressure on the tympanic membrane.) In the middle ear, sound is repeatedly amplified by the system of bones (hammer, anvil and stirrup). These ossicles are supported in weight by two muscles that tighten when sounds are too loud and weaken the ossicles, protecting the hearing aid from injury. With weak sounds, the muscles increase the work of the bones. The intensity of sound in the middle ear increases 30 times due to the difference between the area of ​​the tympanic membrane (90 mm2) to which the malleus is attached and the area of ​​the base of the stirrup (3 mm2).

Rice. 15. . Sound vibrations of the external environment pass through the ear canal to the tympanic membrane, located between the outer and middle ear. The tympanic membrane transmits vibrations and the bony mechanism of the middle ear, which, acting on a lever principle, amplifies the sound by about 30 times. As a result of this, slight changes in pressure at the eardrum are transmitted by a piston-like movement to the oval window of the inner ear, which causes the movement of fluid in the cochlea. Acting on the elastic walls of the cochlear canal, the movement of the fluid causes an oscillatory movement of the auditory membrane, more precisely, of a certain part of it, resonating at the appropriate frequencies. At the same time, thousands of hair-like neurons transform the oscillatory movement into electrical impulses of a certain frequency. The round window and the Eustachian tube coming from it serve to equalize the pressure with the external environment; leaving the nasopharynx, the Eustachian tube opens slightly during swallowing movements.

The purpose of the auditory analyzer is to receive and analyze signals transmitted by vibrations of an elastic medium in the range of 16-20,000 Hz (sound range).

The receptor part of the auditory system - the inner ear - the so-called cochlea. It has 2.5 turns and is divided transversely by a membrane into two isolated channels filled with liquid (relymph). Along the membrane, which narrows from the lower coil of the cochlea to its upper coil, there are 30 thousand sensitive cilia formations - they are sound receptors, forming the so-called organ of Corti. In the cochlea, the primary dissection of sound vibrations occurs. Low sounds affect long eyelashes, high sounds affect short ones. The vibrations of the corresponding sound cilia create nerve impulses that enter the temporal part of the brain, where complex analytical and synthetic activity is carried out. The most important verbal signals for a person are encoded in neural ensembles.

The intensity of the auditory sensation - loudness - depends on the intensity of the sound, that is, on the amplitude of the vibrations of the sound source and on the pitch of the sound. The pitch of the sound is determined by the oscillation frequency of the sound wave, the timbre of the sound is determined by overtones (additional oscillations in each main phase) (Fig. 16).

The pitch of a sound is determined by the number of oscillations of the sound source in 1 second (1 oscillation per second is called hertz). The organ of hearing is sensitive to sounds in the range from 20 to 20,000 Hz, but the highest sensitivity lies in the range of 2000 - 3000 Hz (this is the pitch corresponding to the cry of a frightened woman). A person does not feel the sounds of the lowest frequencies (infrasounds). The sound sensitivity of the ear starts at 16 Hz.

Rice. 16. . The intensity of sound is determined by the amplitude of the vibration of its source. Height - vibration frequency. Timbre - additional vibrations (overtones) in each "time" (middle figure).
However, subthreshold low-frequency sounds affect the mental state of a person. So, sounds with a frequency of 6 Hz cause a person to feel dizzy, tired, depressed, and sounds with a frequency of 7 Hz can even cause cardiac arrest. Getting into the natural resonance of the work of internal organs, infrasounds can disrupt their activity. Other infrasounds also selectively affect the human psyche, increasing its suggestibility, learning ability, etc.

Human sensitivity to high frequency sounds is limited to 20,000 Hz. Sounds that lie beyond the upper threshold of sound sensitivity (that is, over 20,000 Hz) are called ultrasounds. (Ultrasonic frequencies of 60 and even 100,000 Hz are available to animals.) However, since sounds up to 140,000 Hz are found in our speech, we can assume that they are perceived by us at a subconscious level and carry emotionally significant information.

The thresholds for distinguishing sounds by their height are 1/20 of a semitone (that is, up to 20 intermediate steps differ between the sounds produced by two adjacent piano keys).

In addition to high-frequency and low-frequency sensitivity, there are lower and upper thresholds for sensitivity to sound intensity. Sound sensitivity decreases with age. So, for the perception of speech at the age of 30, a sound volume of 40 dB is required, and for the perception of speech at the age of 70, its volume must be at least 65 dB. The upper threshold of auditory sensitivity (in terms of volume) is 130 dB. Noise above 90 dB is harmful to humans. Sudden loud sounds are also dangerous, hitting the autonomic nervous system and leading to a sharp narrowing of the lumen of blood vessels, an increase in heart rate and an increase in the level of adrenaline in the blood. The optimal level is 40 - 50 dB.

Tactile sensation(from Greek. taktilos- touch - the feeling of being touched. Tactile receptors (Fig. 17) are most numerous at the fingertips and tongue. If on the back two touch points are perceived separately only at a distance of 67 mm, then on the tip of the fingers and tongue - at a distance of 1 mm (see table).
Spatial thresholds of tactile sensitivity.

Rice. 17. .

High sensitivity zone	Low sensitivity zone
Tip of the tongue - 1 mm	Sacrum - 40.4 mm
End phalanxes of fingers - 2.2 mm	Buttock - 40.5 mm
The red part of the lips - 4.5 mm	Forearm and lower leg - 40.5 mm
Palmar side of the hand - 6.7 mm	Sternum - 45.5 mm
Terminal phalanx of the big toe - 11.2 mm	Neck below the back of the head - 54.1 mm
The back side of the second phalanges of the toes - 11.2 mm	Loin - 54.1 mm
The back side of the first phalanx of the big toe - 15.7 mm	Back and middle of the neck - 67.6 mm
	Shoulder and hip - 67.7 mm

The threshold of spatial tactile sensitivity is the minimum distance between two point touches at which these effects are perceived separately. The range of tactile distinctive sensitivity is from 1 to 68 mm. The zone of high sensitivity is from 1 to 20 mm. The low sensitivity zone is from 41 to 68 mm.

Tactile sensations combined with motor sensations form tactile sensitivity underlying the subject actions. Tactile sensations are a kind of skin sensations, which also include temperature and pain sensations.

Kinesthetic (motor) sensations.

Rice. 18. (according to Penfield)

Actions are associated with kinesthetic sensations (from the Greek. kineo- movement and aesthesia- sensitivity) - a sense of the position and movement of parts of one's own body. The labor movements of the hand were of decisive importance in the formation of the brain, the human psyche.

Based on muscle-articular sensations, a person determines compliance or inconsistency
their movements to external circumstances. Kinesthetic sensations perform an integrating function in the entire human sensory system. Well-differentiated voluntary movements are the result of the analytical-synthetic activity of a vast cortical zone located in the parietal region of the brain. The motor, motor area of ​​the cerebral cortex is especially closely connected with the frontal lobes of the brain, which perform intellectual and speech functions, and with the visual areas of the brain.

Rice. 19. .

Muscle spindle receptors are especially numerous in the fingers and toes. When moving various parts of the body, hands, fingers, the brain constantly receives information about their current spatial position (Fig. 18), compares this information with the image of the final result of the action and carries out the appropriate correction of the movement. As a result of training, the images of intermediate positions of various parts of the body are generalized in a single general model of a specific action - the action is stereotyped. All movements are regulated on the basis of motor sensations, on the basis of feedback.

The motor physical activity of the body is essential for optimizing the work of the brain: skeletal muscle proprioceptors send stimulating impulses to the brain, increase the tone of the cerebral cortex.

Rice. 20. : 1. Permissible vibration limits for individual parts of the body. 2. The limits of permissible vibrations acting on the entire human body. 3. Borders of weakly felt vibrations.

Static sensations- sensations of the position of the body in space relative to the direction of gravity, a sense of balance. The receptors for these sensations (gravitoreceptors) are located in the inner ear.

receptor rotational body movements are cells with hair endings located in semicircular canals inner ear, located in three mutually perpendicular planes. When accelerating or decelerating the rotational movement, the fluid filling the semicircular canals exerts pressure (according to the law of inertia) on the sensitive hairs, in which the corresponding excitation is caused.

Moving into space in a straight line reflected in otolith apparatus. It consists of sensitive cells with hairs, over which are located otoliths (cushions with crystalline inclusions). Changing the position of the crystals signals to the brain the direction of the rectilinear movement of the body. The semicircular canals and the otolithic apparatus are called vestibular apparatus. It is connected with the temporal region of the cortex and with the cerebellum through the vestibular branch of the auditory nerve (Fig. 19). (Strong overexcitation of the vestibular apparatus causes nausea, since this apparatus is also connected with the internal organs.)

vibration sensations arise as a result of reflection of oscillations from 15 to 1500 Hz in an elastic medium. These vibrations are reflected by all parts of the body. Vibrations are tiring and even painful for a person. Many of them are unacceptable (Fig. 20).

Rice. 21. . The olfactory bulb is the brain center of smell.

Olfactory sensations arise as a result of irritation by particles of odorous substances in the air, the mucous membrane of the nasal cavity, where the olfactory cells are located.
Substances that irritate the olfactory receptors enter the nasopharyngeal cavity from the side of the nose and nasopharynx (Fig. 21). This allows you to determine the smell of a substance both at a distance and if it is in the mouth.

Rice. 22. . The relative concentration of taste receptors on the surface of the tongue.

Taste sensations. The whole variety of taste sensations consists of a combination of four tastes: bitter, salty, sour and sweet. Taste sensations are caused by chemicals dissolved in saliva or water. Taste receptors are nerve endings located on the surface of the tongue - taste buds. They are located on the surface of the tongue unevenly. Separate areas of the surface of the tongue are most sensitive to certain taste influences: the tip of the tongue is more sensitive to sweet, the back to bitter, and the edges to sour (Fig. 22).

The surface of the tongue is sensitive to touch, that is, it is involved in the formation of tactile sensations (the texture of food affects taste sensations).

Temperature sensations arise from irritation of thermoreceptors of the skin. There are separate receptors for the sensation of heat and cold. On the surface of the body, they are located in some places more, in others - less. For example, the skin of the back and neck is most sensitive to cold, and the tips of the fingers and tongue are most sensitive to hot. Different parts of the skin themselves have different temperatures (Fig. 23).

Pain are caused by mechanical, thermal and chemical influences that have reached a superthreshold intensity. Pain sensation is largely associated with subcortical centers, which are regulated by the cerebral cortex. Therefore, they are amenable to some degree of inhibition through the second signal system.

Rice. 23. (according to A.L. Slonim)

Expectations and fears, fatigue and insomnia increase a person's sensitivity to pain; with deep fatigue, the pain dulls. Cold intensifies and heat relieves pain. Pain, temperature, tactile sensations and pressure sensations are related to skin sensations.

organic sensations- sensations associated with interoreceptors located in the internal organs. These include feelings of satiety, hunger, suffocation, nausea, etc.

This classification of sensations was introduced by the famous English physiologist Ch.S. Sherrington (1906);

There are three types of visual sensations: 1) photopic - daytime, 2) scotopic - night and 3) mesopic - twilight. The greatest photopic visual acuity is located in the central field of view; it corresponds to the central, foveal region of the retina. In scotopic vision, maximum light sensitivity is provided by paramolecular areas of the retina, which are characterized by the largest accumulation of rods. They provide the greatest light sensitivity.

Sources and literature

• Enikeev M.I. Psychological encyclopedic dictionary. M., 2010.
• Zinchenko T.P., Kondakov I.M. Psychology. Illustrated dictionary. M. 2003.