Essential characteristics and physiological basis of sensations. Psychology of sensations. Department of Pedagogy and Psychology with EIDO course

CHAPTER 6 SENSATIONS Senses - sight, hearing, taste, smell, touch - turn on and function by themselves. It is important for us to recognize the EMPTINESS, or being, hidden behind sensations. When we make this discovery, meditation becomes a way or way for us to realize and

SENSATIONS The ability to “feel” some information, how to “feel” it in the form of states similar to sensations from one’s body, from movements, from the surrounding space, helped me a lot and helps. Perhaps this will suit you too. We can feel the state flying

Feelings Physical intimacy is the goal of the first type of attachment. The child needs to physically feel the person to whom he is attached, inhaling his scent, looking into his eyes, hearing his voice or feeling his touch. He will do his best to keep

The physiological basis of sensations

Introduction

2. The concept of sensation

3. Physiology of sensations

3.1 Analyzers

3.2 Properties of sensations

3.3 Classification of sensations

4. Types of sensations

4.1 Vision

4.3 Vibratory sensations

4.4 Smell

Bibliography

Introduction

It is known that a person is realized in activities that are possible due to the knowledge of the environment. In ensuring the interaction of a person with the outside world, the leading role is played by the properties of the personality, its motives, attitudes. However, any mental phenomenon is both a reflection of reality and a link in the regulation of activity. The regulation of activity begins already at the level of sensations and perceptions - from mental cognitive processes. Sensations, perceptions, representations, memory belong to sensory forms of knowledge. Sensual reflection in a person is always associated with logical knowledge, thinking. The individual in human sensory cognition is reflected as a manifestation of the general. In sensory cognition, an essential role is played by language, the word, which always performs the function of generalization. In turn, logical cognition (thinking) is based on the data of sensory experience, on sensations, perception and memory representations. In a single process of cognition, a continuous interaction of all cognitive processes is carried out. More complex cognitive processes are based on sensations: perceptions, ideas, memory, thinking, imagination. Otherwise, except through sensations, we cannot learn anything about any forms of movement. Sensation is called the simplest, further no longer decomposable mental process. The sensations reflect the objective qualities of the object (smell, color, taste, temperature, etc.) and the intensity of the stimuli affecting us (for example, a higher or lower temperature).

1. Sensory organization of personality

The sensory organization of the personality is the level of development of individual systems of sensitivity and the possibility of their association. The sensory systems of a person are his sense organs, as if receivers of his sensations, in which sensation is transformed into perception. Every receiver has a certain sensitivity. If we turn to the animal world, we will see that the predominant level of sensitivity of any species is a generic trait. For example, bats have developed sensitivity to the perception of short ultrasonic pulses, dogs have olfactory sensitivity. main feature sensory organization of a person is that it develops as a result of all his life path. The sensitivity of a person is given to him at birth, but its development depends on the circumstances, desire and efforts of the person himself.

2. The concept of sensation

Sensation is a manifestation of the general biological property of living matter - sensitivity. Through sensation there is a psychic connection with the external and internal world. Thanks to sensations, information about all the phenomena of the external world is delivered to the brain. In the same way, a loop is closed through sensations to receive feedback about the current physical and partly mental state of the organism. Through sensations, we learn about taste, smell, color, sound, movement, the state of our internal organs, etc. From these sensations, holistic perceptions of objects and the whole world are formed. It is obvious that the primary cognitive process takes place in human sensory systems, and already on its basis, cognitive processes that are more complex in their structure arise: perceptions, representations, memory, thinking. No matter how simple the primary cognitive process may be, but it is precisely this that is the basis of mental activity, it penetrates into our consciousness only through the “entrances” of sensory systems. the world.

2.1 Processing sensations

After receiving information by the brain, the result of its processing is the development of a response action or strategy aimed, for example, at improving physical tone, focusing more on current activities, or setting up for accelerated inclusion in mental activity. Generally speaking, the response or strategy worked out at any given time is the best choice of the options available to the person at the time of the decision. However, it is clear that the number of available options and the quality of choice are different for different people and depend, for example, on: - the mental properties of the individual; - Strategies for relationships with others; - partly physical condition; - experience, the availability of the necessary information in memory and the possibility of retrieving it; - degree of development and organization of higher nervous processes, etc.

3. Physiology of sensations

3.1 Analyzers

Physiological mechanism sensations is the activity of the nervous apparatus - analyzers, consisting of 3 parts: - receptor - the perceiving part of the analyzer (carries out the transformation of external energy into a nervous process); - the central section of the analyzer - afferent or sensory nerves; - cortical sections of the analyzer, in which the processing of nerve impulses takes place. Certain receptors correspond to their sections of cortical cells. The specialization of each sense organ is based not only on the structural features of the receptor analyzers, but also on the specialization of the neurons that make up the central nervous apparatus, which receive signals perceived by the peripheral senses. The analyzer is not a passive receiver of energy; it is reflexively rebuilt under the influence of stimuli.

3.2 Properties of sensations

Any sensation can be described in terms of several properties inherent in it. The main properties of sensations are: quality, intensity, duration and spatial localization.

Quality- this is a specific feature of this sensation, which distinguishes it from all other types of sensations and varies within a specific modality.

For example, the qualities of visual modality include

Brightness,

Saturation,

Color tone.

Hearing qualities:

Volume,

Quality of tactile sensations:

Hardness,

Roughness, etc.

3.3 Classification of sensations

The most common, earliest and simplest classification of sensations according to the modality (kind) of the stimulus. Modality is a qualitative characteristic in which the specificity of sensation is manifested as the simplest mental signal, in contrast to the nervous signal.

Depending on the location of the receptors, all sensations are divided into three groups. The first group includes sensations that are associated with receptors located on the surface of the body: visual, auditory, olfactory, gustatory and skin sensations. These are exteroceptive sensations. The second group includes interoreceptive sensations associated with receptors located in the internal organs. The third group includes kinesthetic (motor) and static sensations, the receptors of which are located in the muscles, ligaments and tendons - proprioceptive sensations (from Latin "-own").

Depending on the modality of the analyzer, the following types of sensations are distinguished:

- distant(visual, auditory)

- contact(tactile, gustatory) sensations.

4. Types of sensations

Each receptor responds to a specific type of stimulus. Therefore, the following types of sensations can be distinguished:

Visual - arise under the influence of light rays on the retina of the eye; - auditory - are caused by sound waves of speech, music or noise; - vibrational - the ability to capture vibrations of an elastic medium (water, air, earth, objects); this is a kind of auditory sensitivity, poorly developed in humans, but used by dolphins, bats, etc. (echolocation, ultrasound); - olfactory - reflect the smells of surrounding objects; - taste; - skin: tactile (sensation of touch), temperature and pain. The palms, fingertips and lips are very sensitive to touch - we touch them. Pain sensations have a strong emotional connotation - they are well heard or seen by other people. Temperature sensitivity is different in different parts of the body: the back is most sensitive to cold, and the chest is the least sensitive. In special states of the human psyche and body, pseudo-sensations can occur - hallucinations, when the stimulus is absent, but the sensation is present (mirage, visions, "voices", delirium, etc.).

4.1 Vision

The apparatus of vision is the eye - a sensory organ with a complex anatomical structure. Light waves reflected by an object are refracted, passing through the lens of the eye, and focused on the retina in the form of an image. The eye belongs to distant receptors, since vision provides knowledge about objects and phenomena located at some distance from the sense organs.

The ability to reflect space is provided by the pairing of the visual analyzer, the change in the size of the image on the retina when moving away or approaching the object, as well as the movement (convergence and separation) of the axes of the eyes. The retina of the eye consists of several tens of thousands of optic nerve fiber endings, which come into a state of excitation under the influence of a light wave. The endings of the optic nerve differ in shape and function. Cone-shaped receptors are adapted to reflect color. They are located in the center of the retina and are daytime vision devices. Rod-shaped nerve endings reflect light. They are located around the cones, closer to the edge of the retina. This is a night vision device. Cone vision is not impaired when the rods are affected, and vice versa, i.e., the sensations of color and light have their own analyzer systems.

From what has been said, it is clear that two large groups of visual sensations can be distinguished: achromatic sensations, reflecting the transition from white to black, through a mass of shades of gray, and chromatic sensations, which reflect a color gamut with numerous shades and color transitions.

Auditory sensations are also distant sensations. The sensory endings of the auditory nerve are located in the inner ear, the cochlea with the auditory membrane and sensory hairs. The auricle, the so-called outer ear, collects sound vibrations, and the mechanism of the middle ear transmits them to the cochlea. The sensory endings of the cochlea are excited as a result of resonance, i.e. the endings of the auditory nerve, different in length and thickness, set in motion at a certain number of oscillations per second, and the received signals are transmitted to the brain. These oscillations occur in elastic bodies and are transmitted by the air medium. We know from physics that sound has a wave nature and is characterized by frequency and amplitude.

There are three types of auditory sensations: speech, music and noise. In these types of sensations, the sound analyzer distinguishes four qualities of sound:

Strength (loud - weak),

Height (high - low),

Sound duration and tempo-rhythmic pattern of perceived sounds.

Phonemic hearing is called hearing, using which you can distinguish the sounds of speech. It is formed during life and depends on the speech environment. Good knowledge foreign language involves the development of a new system phonemic hearing. The ability to learn foreign languages ​​is determined by phonemic hearing, which also affects literacy. writing. The musical ear of a person is brought up and formed, as well as speech. The ability to enjoy music is a centuries-old result of the development of the musical culture of mankind. Noises and rustles are less significant for a person, unless they interfere with his life. Noises can evoke a pleasant emotional mood, for example, the sound of rain, the roar of the surf, and, one of my acquaintances, a computer network administrator, said that he cannot fall asleep when he does not hear the noise of working fans from three or four computers. Noises can also serve as a danger signal - the hiss of gas, the clatter of feet behind your back, the howl of a siren.

4.3 Vibratory sensations

Vibration sensitivity is adjacent to auditory sensations. They share the nature of reflected physical phenomena. Vibration sensations reflect vibrations of an elastic medium. This type of sensitivity is figuratively called "contact hearing". No specific vibration receptors have been found in humans. At present, it is believed that the vibrational feeling is one of the most ancient types of sensitivity, and all tissues of the body can reflect the vibrations of the external and internal environment.

In human life, vibrational sensitivity is subordinated to auditory and visual. The cognitive value of vibration sensitivity increases in those activities where vibrations become a signal of malfunctions in the operation of the machine. In the life of the deaf and deaf-blind, vibrational sensitivity compensates for hearing loss. On the body of a healthy person, short vibrations have a tonic effect, long and intense vibrations are tiring and can cause painful phenomena.

4.4 Smell

Olfactory sensations are distant. Irritants that cause olfactory sensations are microscopic particles of substances that enter the nasal cavity with air, dissolve in the nasal fluid and act on the receptor. In a number of animals, the sense of smell is the main distant receptor: guided by the smell, the animal finds food or avoids danger.

In humans, olfactory sensations have little to do with orientation in environment. This function of smell is suppressed by vision and hearing. The lack of development and instability of olfactory sensations is evidenced by the absence in the language of special words for their designation, sensations are not abstracted from the object that names it. They say: "the smell of hay", "the smell of rotten apples", "the smell of lilies of the valley".

Olfactory sensitivity is closely related to taste, helps to recognize the quality of food. The sense of smell warns of an air environment dangerous for the body, and in some cases makes it possible to distinguish the chemical composition of substances.

Taste sensations are contact, arising from the contact of the sense organ (tongue) with the object itself. The sense of taste detects molecules dissolved in saliva. There are four main qualities of taste stimuli: sour, sweet, bitter, salty. From the combinations of these four sensations, to which tongue movements are added, a complex of taste sensations arises. Initially, the sensory process occurs in the taste buds, and each of the papillae has from 50 to 150 receptor cells, which are quickly worn out from contact with food and then renewed. Sensory signals then travel along nerves to the hindbrain, thalamus, and gustatory cortex, which processes taste sensations.

Taste sensations, like olfactory ones, increase a person's appetite. By analyzing the quality of food, taste sensations also have a protective function and are important for survival. When fasting, taste sensitivity increases, when satiated or satiated, it decreases.

In the skin there are several independent analyzer systems:

Tactile (sensation of touch),

temperature,

Painful.

All types of skin sensitivity are referred to as contact sensitivity. The largest accumulation of tactile cells is in the palm, on the fingertips and on the lips. Skin receptors transmit information to spinal cord, making contact with motor neurons, which makes possible reflex actions such as, for example, pulling the hand away from the fire. The sense of touch is the tactile sensations of the hand along with the musculo-articular sensitivity.

Temperature sensitivity regulates heat transfer between the body and the environment. The distribution of heat and cold receptors over the skin is uneven. The back is most sensitive to cold, the least - the chest.

Strong pressure on the surface of the body causes pain. The receptor endings of pain sensitivity are located under the skin, deeper than the tactile receptors. Where there are more tactile receptors, there are fewer pain receptors. Tactile sensitivity gives knowledge about the qualities of the object, and pain sensitivity gives a signal about the harm caused by the stimulus.

4.7 Proprioceptive sensitivity

Kinesthesia

Kinesthetic sensations are sensations of movement and position of individual parts of the body. Kinesthetic sensation receptors are located in muscles and tendons. Irritation in these receptors occurs under the influence of muscle stretching and contraction.

A large number of motor receptors are located in the fingers, tongue and lips, since these organs need to carry out precise and subtle working and speech movements. The activity of the motor analyzer allows a person to coordinate and control his movements.

Speech kinesthesias are formed in the infantile and preschool periods of human development. Teaching a foreign language requires the development of such speech kinesthesias that are not typical for mother tongue.

vestibular sense

Static, or gravitational, sensitivity reflects the position of our body in space. Its receptors are located in the vestibular apparatus of the inner ear: the semicircular canals and vestibular sacs convert signals about relative movement and gravity and transmit them to the cerebellum and the cortex of the temporal region. Sudden and frequent changes in the position of the body relative to the plane of the earth, such as swinging on a swing or sea rolling, lead to dizziness - "seasickness".

Page 4 of 10

PHYSIOLOGICAL BASES OF SENSATIONS. THE CONCEPT OF THE ANALYZER.

All living beings that have a nervous system have the ability to sense. As for conscious sensations (about the source and quality of which an account is given), only a person has them. In the evolution of living beings, sensations arose on the basis of primary irritability, which is a property of living matter to respond to biologically significant environmental influences by changing its internal state and external behavior.

In their origin, from the very beginning, sensations were associated with the activity of the organism, with the need to satisfy its biological needs. The vital role of sensations is to promptly bring to the central nervous system (as the main organ for managing human activity and behavior) information about the state of the external and internal environment, the presence of biologically significant factors in it. Sensation, in contrast to irritability, carries information about certain qualities of external influence.

A person's sensations in their quality and diversity reflect the diversity of the properties of the environment that are significant for him. The sense organs, or human analyzers, are adapted for perception and processing from the moment of birth. various kinds energy in the form of stimuli-stimuli (physical, mechanical, chemical and others). Stimulus- any factor that affects the body and can cause any reaction in it.

It is necessary to distinguish between stimuli that are adequate for a given sense organ and those that are not adequate for it. This fact testifies to the subtle specialization of the sense organs to reflect one or another type of energy, certain properties of objects and phenomena of reality. The specialization of the sense organs is a product of a long evolution, and the sense organs themselves are products of adaptation to the influences of the external environment, therefore, in their structure and properties, they are adequate to these influences.

In humans, subtle differentiation in the field of sensations is associated with historical development human society and social work practices. “Serving” the processes of adaptation of the organism to the environment, the sense organs can successfully perform their function only if they correctly reflect its objective properties. Thus, the non-specificity of the sense organs gives rise to the specificity of sensations, and the specific qualities of the external world gave rise to the specificity of the sense organs. Sensations are not symbols, hieroglyphs, but reflect the actual properties of objects and phenomena of the material world that act on the senses of the subject, but exist independently of him.

Sensation arises as a reaction of the nervous system to a particular stimulus and, like any mental phenomenon, has a reflex character. Reaction The body's response to a specific stimulus.

The physiological basis of sensation is a nervous process that occurs when a stimulus acts on an analyzer adequate to it. Analyzer- a concept (according to Pavlov), denoting a set of afferent and efferent nervous structures involved in the perception, processing and response to stimuli.

efferent is a process directed from the inside out, from the central nervous system to the periphery of the body.

Afferent- a concept that characterizes the course of the process of nervous excitation through the nervous system in the direction from the periphery of the body to the brain.

The analyzer consists of three parts:

1. Peripheral department ( or receptor), which is a special transformer of external energy into the nervous process. There are two types of receptors: contact receptors- receptors that transmit irritation by direct contact with objects that act on them, and distant receptors- receptors that respond to stimuli emanating from a distant object.

2. Afferent (centripetal) and efferent (centrifugal) nerves, conducting paths connecting the peripheral section of the analyzer with the central one.

3. Subcortical and cortical sections (brain end) of the analyzer, where the processing of nerve impulses coming from the peripheral sections takes place (see Fig. 1).

In the cortical region of each analyzer is analyzer core, i.e. the central part, where the main mass of receptor cells is concentrated, and the periphery, consisting of scattered cellular elements, which are located in one quantity or another in various areas of the cortex.

The nuclear part of the analyzer consists of a large mass of cells that are located in the area of ​​the cerebral cortex where the centripetal nerves from the receptor enter. Scattered (peripheral) elements of this analyzer enter the regions adjacent to the nuclei of other analyzers. This ensures participation in a separate act of sensation of a large part of the entire cerebral cortex. The analyzer core performs the function of fine analysis and synthesis, for example, it differentiates sounds by pitch. Scattered elements are associated with rough analysis functions, such as distinguishing between musical sounds and noises.

Certain cells of the peripheral parts of the analyzer correspond to certain parts of the cortical cells. So, spatially different points in the cortex are represented, for example, different points retina of the eye; spatially different arrangement of cells is presented in the cortex and the organ of hearing. The same applies to other sense organs.

Numerous experiments carried out by methods of artificial stimulation now make it possible to quite definitely establish the localization in the cortex of certain types of sensitivity. Thus, the representation of visual sensitivity is concentrated mainly in the occipital lobes of the cerebral cortex. Auditory sensitivity is localized in the middle part of the superior temporal gyrus. Tactile-motor sensitivity is represented in the posterior central gyrus, etc.

For the sensation to arise, the work of the entire analyzer as a whole is necessary. The impact of the stimulus on the receptor causes the appearance of irritation. The beginning of this irritation lies in the transformation of external energy into a nervous process, which is produced by the receptor. From the receptor, this process along the centripetal nerve reaches the nuclear part of the analyzer located in the spinal cord or brain. When the excitation reaches the cortical cells of the analyzer, we feel the qualities of the stimuli, and after this, the body's response to the irritation occurs.

If the signal is due to a stimulus that threatens to cause damage to the body, or is addressed to the autonomic nervous system, then it is very likely that it will immediately cause a reflex reaction emanating from the spinal cord or other lower center, and this will happen before we are aware of this effect ( reflex- an automatic response of the body to the action of any internal or external stimulus).

Our hand recoils when we get burned by a cigarette, our pupil constricts in bright light, our salivary glands start to salivate when we put a lollipop in our mouth, and all this happens before our brain can decipher the signal and give the appropriate order. The survival of an organism often depends on the short neural circuits that make up the reflex arc.

If the signal continues down the spinal cord, then it takes two different paths: one leads to the cerebral cortex via thalamus, and the other, more diffuse, passes through filter reticular formation , which keeps the cortex awake and decides whether the signal transmitted directly is important enough for the cortex to “engage” in deciphering it. If the signal is considered important, a complex process will begin, which will lead to a sensation in literally this word. This process involves changing the activity of many thousands of cortical neurons, which will have to structure and organize the sensory signal in order to give it meaning. ( Sensory- associated with the work of the senses).

First of all, the attention of the cerebral cortex to the stimulus will now entail a series of movements of the eyes, head or torso. This will allow you to get acquainted with the information coming from the sensory organ, the primary source of this signal, in a deeper and more detailed way, and also, possibly, connect other senses. As new information becomes available, it will be associated with traces of similar events stored in memory.

Between the receptor and the brain there is not only a direct (centripetal), but also a reverse (centrifugal) connection. The feedback principle discovered by I.M. Sechenov, requires the recognition that the sense organ is alternately both a receptor and an effector.

Thus, sensation is not only the result of a centripetal process; it is based on a complete and complex reflex act, which, in its formation and course, obeys general laws reflex activity. In this case, the analyzer constitutes the initial and most important part of the entire path of nervous processes, or the reflex arc.

reflex arc- a concept denoting a set of nervous structures that conduct nerve impulses from stimuli located on the periphery of the body to the center , processing them in the central nervous system and causing a reaction to the corresponding stimuli.

The reflex arc consists of a receptor, pathways, a central part, and an effector. The interconnection of the elements of the reflex arc provides the basis for the orientation of a complex organism in the surrounding world, the activity of the organism, depending on the conditions of its existence.

Figure 2 shows a variant of the action of a human reflex arc in the event of a mosquito bite (according to J. Godefroy).

The signal from the receptor (1) is sent to the spinal cord (2) and the reflex arc turned on can cause hand withdrawal (3). The signal, meanwhile, travels further to the brain (4), heading along a direct path to the thalamus and cortex (5) and along an indirect path to the reticular formation (6). The latter activates the cortex (7) and prompts it to pay attention to the signal it has just become aware of. Attention to the signal is manifested in the movements of the head and eyes (8), which leads to the recognition of the stimulus (9), and then to the programming of the reaction of the other hand in order to “drive away the unwanted guest” (10).

The dynamics of the processes occurring in the reflex arc is a kind of likening to the properties of an external influence. For example, touch is just such a process in which hand movements repeat the outlines of a given object, as if becoming like its structure. The eye operates on the same principle due to the combination of the activity of its optical “device” with oculomotor reactions. movements vocal cords also reproduce the objective pitch nature. When the vocal-motor link was turned off in the experiments, the phenomenon of a kind of pitch deafness inevitably arose. Thus, due to the combination of sensory and motor components, the sensory (analyzing) apparatus reproduces the objective properties of the stimuli affecting the receptor and resembles their nature.

Numerous and versatile studies on the participation of effector processes in the occurrence of sensation have led to the conclusion that sensation as a mental phenomenon is impossible in the absence of an organism's response or in its inadequacy. In this sense, the fixed eye is as blind as the fixed hand ceases to be an instrument of knowledge. The sense organs are closely connected with the organs of movement, which perform not only adaptive, executive functions, but also directly participate in the processes of obtaining information.

Thus, the connection between touch and movement is obvious. Both functions are merged in one organ - the hand. At the same time, the difference between the executive and groping movements of the hand is also obvious (Russian physiologist, author of the doctrine of higher nervous activity) I.P. Pavlov called the latter orienting-exploratory reactions related to a special type of behavior - perceptual rather than executive behavior. Such perceptual regulation is aimed at enhancing the input of information, optimizing the process of sensation. All this suggests that for the emergence of a sensation it is not enough that the organism is subjected to the corresponding action of a material stimulus, but some work of the organism itself is also necessary. This work can be expressed both in internal processes and in external movements.

In addition to the fact that the sense organs are a kind of “window” for a person into the world around them, they are, in fact, energy filters through which the corresponding changes in the environment pass. On what basis is the selection useful information in feelings? In part, we have already touched on this issue. To date, several hypotheses have been formulated.

According to the first hypothesis, there are mechanisms for detecting and passing restricted signal classes, with messages not matching those classes being rejected. The task of such selection is performed by comparison mechanisms. For example, in insects, these mechanisms are involved in solving the difficult task of finding a partner of their own species. "Winks" of fireflies, "ritual dances" of butterflies, etc. - all these are genetically fixed chains of reflexes that follow one after another. Each stage of such a chain is sequentially solved by insects in a binary system: “yes” - “no”. Not the movement of the female, not the spot of color, not the pattern on the wings, not the way she “answered” in the dance - it means that the female is alien, of a different species. The stages form a hierarchical sequence: the beginning of a new stage is possible only after the previous question is answered “yes”.

Second hypothesis suggests that the acceptance or non-acceptance of messages can be regulated on the basis of special criteria, which, in particular, represent the needs of a living being. All animals are usually surrounded by a "sea" of stimuli to which they are sensitive. However, most living organisms respond only to those stimuli that are directly related to the needs of the organism. Hunger, thirst, readiness for mating, or some other internal attraction can be the regulators, the criteria by which the selection of stimulus energy is carried out.

According to the third hypothesis, the selection of information in sensations occurs on the basis of the criterion of novelty. Under the action of a constant stimulus, the sensitivity seems to be dulled and the signals from the receptors cease to flow to the central nervous apparatus ( sensitivity- the ability of the body to respond to environmental influences that do not have direct biological significance, but cause a psychological reaction in the form of sensations). Thus, the sensation of touch tends to fade away. It can completely disappear if the irritant suddenly stops moving across the skin. Sensitive nerve endings signal the brain that irritation is present only when the strength of the irritation changes, even if the time during which it presses harder or weaker on the skin is very short.

The same is true with hearing. It was found that the singer to control own voice and to keep it at the right pitch, vibrato is needed - a slight fluctuation in pitch. Without stimulation of these deliberate variations, the singer's brain does not notice the gradual changes in pitch.

The visual analyzer is also characterized by the extinction of the orienting reaction to a constant stimulus. The visual sensory field, it would seem, is free from the obligatory connection with the reflection of movement. Meanwhile, the data of the genetic psychophysiology of vision show that the initial stage of visual sensations was precisely the display of the movement of objects. The compound eyes of insects work effectively only when exposed to moving stimuli.

This is the case not only in invertebrates, but also in vertebrates. It is known, for example, that the retina of a frog, described as a “detector of insects,” reacts precisely to the movement of the latter. If there is no moving object in the frog's field of vision, its eyes do not send essential information to the brain. Therefore, even being surrounded by many motionless insects, the frog can die of hunger.

The facts testifying to the extinction of the orienting reaction to a constant stimulus were obtained in the experiments of E.N. Sokolov. The nervous system finely models the properties of external objects acting on the sense organs, creating their neural models. These models perform the function of a selectively acting filter. If there is a mismatch affecting the receptor in this moment irritant with the previously formed nervous model, impulses of mismatch appear, causing an orienting reaction. Conversely, the orienting reaction fades to the stimulus that was previously used in the experiments.

Thus, the process of sensation is carried out as a system of sensory actions aimed at the selection and transformation of the specific energy of external influence and providing an adequate reflection of the surrounding world.

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

Inverse relationship

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

Sensory organization

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

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

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

Data processing

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

Analyzers

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

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

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

Information properties

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

Features of differentiation

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

Types

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

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

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

Vision

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

Hearing

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

Vibration sensitivity

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

Smell

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

Taste

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

Leather

It contains several independent sensory structures:

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

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

Kinesthetic Sensitivity

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

vestibular sensitivity

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

Conclusion

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

The diversity of the surrounding world to a certain extent becomes available to us due to the diversity of our sensations.

Sensation is a mental process of reflecting the individual properties of objects and phenomena of the surrounding world, as well as the internal states of the body with the direct influence of stimuli on the corresponding analyzer systems.

Sensation, their nature, the laws of formation and change are studied in a special area of ​​psychology, which is called psychophysics. It arose in the second half of the 19th century, and its name is associated with the main question that is posed and solved in this field of knowledge - with the question of the relationship between sensations and sensations. physical characteristics stimuli affecting the sense organs.

Evolutionary sensations arose on the basis irritations, which are inherent in living matter, which selectively reacts by changing its internal state to biologically significant environmental influences. An elementary response to irritation appears in the simplest unicellular living organisms, which react to the influence of the environment by movement. Irritation, or excitability of the sense organs, is the most important prerequisite for the body to display the objective properties of the environment, which is the essence of sensory processes. According to the hypothesis of O. M. Leont "eva, sensibility "is genetically nothing more than irritation in relation to this kind of environmental influence, which correlates the organism in other influences, i.e. orient the organism in the environment, performing a signal function." Thanks to sensuality, the signs of objects (smells, shape, color), are in themselves indifferent (in the sense that they cannot satisfy organic needs), acquire a signal value.The more developed the senses, the more opportunities to reflect the influence of the external environment.It is necessary to distinguish between stimuli, adequate for a given sense organ and not adequate for it.Specialization of the sense organs to display one or another type of energy, certain properties of objects or phenomena of reality is a product of long evolution, and the sense organs themselves are a product of adaptation to environmental influences.Adequate reflection of reality on the sensory -perceptual level is necessary from an evolutionary-historical point of view, because which is a precondition for survival.

The physiological basis of sensation is a nervous process that occurs when a stimulus is applied to the corresponding analyzer. Speaking of analyzers, two things should be kept in mind. Firstly, this name is not entirely accurate, because the analyzer provides not only analysis, but also the synthesis of stimuli into sensations and images. Secondly, analysis and synthesis can occur outside the conscious control of these processes by a person. Most of the stimuli she feels, processes, but is not aware of.

The feeling is reflex in nature; physiologically it is provided by the analyzer system. The analyzer is a nervous apparatus that performs the function of analyzing and synthesizing stimuli that come from the external and internal environment of the body. The concept of the analyzer And introduced. P. Pavlov. The analyzer consists of three parts:

1) peripheral department - receptor that transforms a certain type of energy into a nervous process;

2) afferent(centripetal) paths that transmit the excitation that arose in the receptor in the higher centers of the nervous system, and efferent (centrifugal), along which impulses from the higher centers are transmitted to lower levels;

3) subcortical and cork projective zones where the processing of nerve impulses from the peripheral regions takes place.

Historically, it so happened that those analyzer systems, the receptor part of which (represented from the anatomical point of view) exists in the form of separate external organs (nose, ear, etc.), are called sense organs. Sight, hearing, smell, touch and taste are distinguished by Aristotle. In reality, there are many more types of sensations. A significant part of physical influences acquires a direct vital significance for living beings, or is simply not perceived by them. For some of the influences that are found on Earth in its pure form and in quantities that threaten human life, it simply does not have the appropriate sense organs. Such an irritant is, for example, radiation. It is also not given to a person to consciously perceive, reflect in the form of sensations ultrasounds, light rays, the wavelength of which goes beyond the allowable range.

The analyzer constitutes the initial and most important part of the entire path of nervous processes, or the reflex arc.

Reflex arc = analyzer + effector. An ephector is a motor organ (a certain muscle) that receives a nerve impulse from the central nervous system (brain). The relationship of the elements of the reflex arc provides the basis for the orientation of a complex organism in the environment, the activity of the organism, depending on the conditions of its existence.

For a feeling to arise, it is not enough that the organism is subjected to the corresponding influence of a material stimulus; some work of the organism itself is also necessary. The process of sensation is optimized through perceptual regulation. The sense organs are closely connected with the organs of movement, which perform not only adaptive, executive functions, but also directly participate in the processes of obtaining information.

In the first case (I), the muscle apparatus acts as an effector. In the second case (II), the organ of sensation itself can be either a receptor or an efector.

Not a single sensory impulse, not a single receptor stimulation by itself can unambiguously determine an adequate image of sensation and perception without muscular correction (since errors are inevitable and require feedback). When receiving a sensory image, this feedback is always present, so there is reason to talk not about a reflex arc, but about a closed reflex ring.

Correction of the sensual image occurs with the help of perceptual actions, in which the image of the object is compared with the real-practical features of this object. The effector components of these actions include hand movements that feel the object, eye movements that track the visible contour, larynx movements that reproduce the heard sound, and others. In all these cases, a copy is created that is comparable to the original, and branching signals, entering the nervous system, can perform a corrective function in relation to the image, and therefore to practical actions. Thus, perceptual action is a self-regulating model what controls the feedback mechanism and adapts to the characteristics of the object under study.