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1. Psychology of sensations.

1. Psychology of sensations.

The simplest mental process from which a person’s cognition of the surrounding world begins is sensation. In the evolution of living beings, sensations arose on the basis of primary irritability, which is the property of living matter to selectively respond to biologically significant changes in the environment. Subsequently, these functions were taken over by the nervous system. A stimulus (visual, auditory, etc.) affects the sense organs, resulting in nerve impulses that enter the brain along nerve pathways and are processed there to form individual sensations. Sensation is the primary “building” material on the basis of which a holistic reflection in consciousness of the complexity and versatility of the surrounding world, the image of one’s bodily and mental “I” is built. Sensations are essentially subjective images of the objective world - the external and internal states of the body.

Sensation is a mental process of reflecting individual properties of objects and phenomena during their direct impact to the senses.

Since the time of Aristotle, five types (modalities) of sensations have traditionally been identified that inform a person about changes in environment: touch, taste, smell, hearing and vision.

It has now been established that there are also many other types of sensations, and the body is equipped with very complex mechanisms that ensure the interaction of the senses with each other. Thus, the sense of touch, along with tactile sensations (touch sensations), includes a completely independent type of sensation - temperature, which is a function of a special temperature analyzer. Vibration sensations occupy an intermediate position between tactile and auditory sensations. The sensations of balance and acceleration associated with the functions of the vestibular apparatus play a large role in a person’s orientation. Pain sensations that signal the destructive power of the stimulus are also common to different analyzers.

Depending on the type and location of the receptors, all sensations are usually divided into three groups:

1) exteroceptive (exteroceptive), reflecting the properties of objects and phenomena of the external environment and having receptors on the surface of the body;

2) interoceptive (interoceptive), having receptors located in the internal organs and tissues of the body and reflecting the state of the internal environment of the body;

3) proprioceptive (proprioceptive), whose receptors are located in muscles, ligaments, joints and provide information about the movement and position of the body. Motion sensitivity is also often called kinesthesia, and the corresponding receptors are kinesthetic.

Exteroceptive sensations can be divided into two more groups: contact(e.g. tactile, gustatory) and distant(e.g. visual, auditory). Contact receptors transmit irritation upon direct contact with an object, and distant receptors react to irritation emanating from a distant object.

For most created to end of the 19th century V. Psychological laboratories are characterized by reducing the main problems of experimental research to the study of elementary mental processes - sensations and perceptions. Until the beginning of the 20th century. The leading centers of world experimental psychology were the laboratories of V. Wundt in Germany (1879) and V.M. Bekhterev in Russia (1886 - in Kazan, 1894 - in St. Petersburg). The work of scientists in these laboratories on studying the mechanisms of perception prepared the subsequent experimental study of emotions, associations and memory, and then thinking.

2. General patterns of sensations

Sensations are a form of reflection of adequate stimuli. Thus, an adequate stimulator of visual sensation is electromagnetic waves in the range of 380-770 mmk. Auditory sensations arise under the influence of sound waves with a frequency of 16 to 20,000 Hz. Other sensations also have their own specific stimuli. However different kinds sensations are characterized not only by specificity, but also by properties common to all of them. These properties include quality, intensity, duration and spatial location.

Quality- This main feature of a given sensation, distinguishing it from other types of sensations and varying within a given type of sensation (one modality). Auditory sensations, for example, differ in pitch, timbre, and volume, while visual sensations differ in saturation and color tone.

Intensity sensation is his quantitative characteristics and is determined both by the strength of the stimulus and the functional state of the receptor.

Duration sensations are also determined by the intensity of the effect on the receptor, its functional state, but mainly by the time of action on the receptor.

When a stimulus is applied, the sensation does not occur immediately, but after some time. For painful sensations, the latent period is 370 ms, for tactile sensations - 130, and the taste sensation occurs within 50 ms after the application of a chemical irritant to the tongue.

Just as a sensation does not arise simultaneously with the onset of the stimulus, it does not disappear immediately after the cessation of its effect. This inertia of sensations is called aftereffect. For example, the trace of a stimulus in the visual analyzer remains in the form sequential image, first positive and then negative. A positive sequential image does not differ in lightness and color from the original image (in cinema, this property of the visual analyzer is used to create the illusion of movement), and then a negative image appears, and color sources of color are replaced by complementary colors.

If you look at the red color first, then the white surface will appear green. If the original color was blue, then the sequential image will be yellow, and if you initially look at a black surface, then the sequential image will be white.

Auditory sensations can also be accompanied by sequential images. For example, everyone is well aware of the phenomenon of “ringing in the ears” after exposure to deafening sounds.

A similar effect is typical for the muscular system. Stand in the doorway and strongly “push” the doorframes away from you with your hands; After this, moving to the side and relaxing the muscles of your arms, you will feel that your arms are rising up by themselves.

Academician D.N. Uznadze (1963) asked subjects to touch a large ball with their right hand and a small ball with their left, and then balls of the same size 10-15 times. It turned out that the ball felt with the right hand seemed smaller in contrast, and the ball felt with the left hand seemed larger.

3. Basic characteristics of sensations

1. Sensitivity range . A stimulus is capable of causing a sensation only when it reaches a certain magnitude or strength.

The lower absolute threshold of sensation(J0) is the minimum force (intensity, duration, energy or area) of impact that causes a barely noticeable sensation. The lower J0, the higher the sensitivity of the analyzer to the stimulus. For example, the lower limit (threshold) of sensitivity for pitch of sound is 15 Hz, for light - 0.001 light. etc.

Stimuli of lesser strength are called subliminal(subsensory), and signals about them are not transmitted to the cerebral cortex. If the light intensity is reduced so much that a person can no longer tell whether he saw a flash of light, then a galvanic skin response is nevertheless recorded by hand at that moment. This suggests that the light signal, although not realized, was processed by the nervous system. The operation of a “lie detector” is based on this procedure.

The transition from a subthreshold sensation occurs abruptly: if the impact has almost reached the threshold value, then a barely noticeable increase in its strength is enough for the stimulus to immediately become completely felt. Subthreshold impulses are not indifferent to the body. This is confirmed by numerous facts obtained in clinics of nervous diseases and psychiatry, when it is weak, subthreshold stimuli coming from the external or internal environment that create a dominant focus in the cerebral cortex and contribute to the emergence of “deceptions of the senses” - hallucinations.

Some scientists note the similarity between subliminal perception (sensation) and extrasensory perception, when we are also talking about signals that are too weak to reach the level of consciousness, but are still picked up by some people at a certain time and in a certain state. Extrasensory perception includes clairvoyance (the ability to see things that cannot be seen at a distance), telepathy (obtaining information about a person who is far away, transmitting thoughts), precognition (the ability to guess the future).

The border zone of psychology, studying the so-called psi phenomena, arose in the early 1930s (L.L. Vasiliev in the USSR and J. Rhine in the USA), although in scientific circles this work began to be openly discussed only in recent decades. The Parapsychological Association, which studied “anomalous” phenomena, was admitted to the American Association for Scientific Progress in 1969. This area, recently recognized as a scientific discipline, is called parapsychology in Germany and the USA, metapsychology in France, and bioinformatics in Russia. Its new general name is psychology. The main difficulty in fully recognizing the results in this area is that it is not always possible to reproduce the phenomena being studied, which is certainly necessary for facts that claim to be scientific.

Upper absolute threshold of sensation(Jmax) is the maximum value of the stimulus that the analyzer is capable of adequately perceiving. Impacts exceeding Jmax cease to be differentially felt or cause pain; Jmax is much more variable between individuals and ages than J0. The interval between J0 and Jmax is called sensitivity range.

2. Differential (difference) sensitivity threshold . With the help of our senses, we can not only ascertain the presence or absence of a particular stimulus, but also distinguish between stimuli by their strength and quality. The minimum magnitude of the difference in the strength of two homogeneous stimuli that a person is able to feel is called threshold of discrimination(aJ). The lower the difference threshold value, the higher the ability of this analyzer to differentiate irritation.

The German physiologist E. Weber established that an increase in the intensity of a stimulus, capable of causing a barely noticeable increase in the intensity of sensation, always constitutes a certain part of the initial value of the stimulus. Thus, an increase in pressure on the skin is already felt if the load is increased by only 3% (3 g should be added to a weight weighing 100 g, and 6 g should be added to a weight weighing 200 g, etc.). This dependence is expressed by the following formula: dJ/J = const, where J is the strength of the stimulus, dJ is its barely noticeable increase (discrimination threshold), const is a constant value (constant), different for different sensations (pressure on the skin - 0.03, vision - 0.01, hearing - 0.1, etc.).

3. Operational signal discernibility threshold - this is the value of discrimination between signals at which the accuracy and speed of discrimination reach their maximum. The operational threshold is 10-15 times higher than the differential threshold.

4. Psychophysical Weber-Fechner law - describes the dependence of the intensity of sensation (E) on the strength of the stimulus (J).

German physicist, psychologist and philosopher G.T. Fechner (1801-1887) expressed this dependence, which was first discovered by E. Weber, with the following formula (basic psychophysical law): E = k . logJ + c (the intensity of the sensation increases in proportion to the logarithm of the stimulus strength), where k is the proportionality coefficient; c is a constant that is different for sensations of different modalities.

The American scientist S. Stevens believes that the basic psychophysical law is better expressed not by a logarithmic, but by a power function. However, in any case, the strength of sensation increases significantly more slowly than the magnitude of physical stimuli. These patterns are associated with the characteristics of the electrochemical processes occurring in the receptors when converting the effect into a nerve impulse.

5. Time threshold - the minimum duration of exposure to the stimulus required for the occurrence of sensations. For vision it is 0.1-0.2 s, and for hearing - 50 ms.

6. Spatial threshold - determined by the minimum size of a barely perceptible stimulus. For example, visual acuity is expressed by the ability of the eye to distinguish small details of objects. Their sizes are expressed in angular values, which are related to linear sizes by the formula tgC/2=h/2L, where C is the angular size of the object, h is the linear size, L is the distance from the eye to the object. With normal vision, the spatial threshold of visual acuity is 1", but the minimum acceptable dimensions of image elements for confident identification of objects should be 15" for simple objects, and at least 30-40 for complex ones.

7. Latent period of reaction - the period of time from the moment the signal is given to the moment the sensation occurs. It is different for sensations of different modalities. For example, for vision it is 160-240 ms. It should also be remembered that after the end of the stimulus, the sensations do not disappear immediately, but gradually (the inertia of vision is 0.1-0.2 s), therefore the duration of the signal and the interval between appearing signals must be no less than the time the sensations persist.

When designing modern technology, engineers need to know and take into account the psychological capabilities of a person to receive information. The main characteristics of analyzers can be found in the relevant manuals and reference books on engineering psychology.

4. Changes in sensitivityand processes of interaction between analyzers

There are two main forms of change in the sensitivity of the analyzer - adaptation and sensitization.

Adaptation called a change in the sensitivity of the analyzer under the influence of its adaptation to the current stimulus. It can be aimed at either increasing or decreasing sensitivity. For example, after 30-40 minutes of being in the dark, the sensitivity of the eye increases by 20 thousand times, and subsequently by 200 thousand times. The eye adapts (adapts) to the dark within 4-5 minutes - partially, 40 minutes - enough and 80 minutes - completely. Such an adaptation, which leads to an increase in the sensitivity of the analyzer, is called positive.

Negative adaptation accompanied by a decrease in the sensitivity of the analyzer. So, in the case of constant stimuli, they begin to be felt weaker and disappear. For example, it is a common fact for us to experience a distinct disappearance of olfactory sensations shortly after we enter an atmosphere with unpleasant smell. The intensity of the taste sensation also weakens if the corresponding substance is kept in the mouth for a long time. Close to what is described is the phenomenon of dulling of sensation under the influence of a strong stimulus. For example, if you come out of the darkness into bright light, then after “blinding” the sensitivity of the eye sharply decreases, and we begin to see normally.

The phenomenon of adaptation is explained by the action of both peripheral and central mechanisms. When mechanisms regulating sensitivity act on the receptors themselves, they speak of sensory adaptation. In the case of more complex stimulation, which, although captured by receptors, is not so important for activity, central regulation mechanisms come into play at the level of the reticular formation, which blocks the transmission of impulses so that they do not “clutter” consciousness with excess information. These mechanisms underlie habituation-type adaptation to stimuli ( habituations).

Sensitization - increased sensitivity to the effects of a number of stimuli. Physiologically it is explained by an increase in the excitability of the cerebral cortex to certain stimuli as a result of exercise or interaction of analyzers. According to I.P. Pavlov, a weak stimulus causes an excitation process in the cerebral cortex, which easily spreads (irradiates) throughout the cortex. As a result of the irradiation of the excitation process, the sensitivity of other analyzers increases. On the contrary, under the influence of a strong stimulus, an excitation process occurs, which tends to concentrate, and, according to the law of mutual induction, this leads to inhibition in the central sections of other analyzers and a decrease in their sensitivity. Thus, when a quiet tone of equal intensity is sounded and at the same time the rhythmic impact of light on the eye, it will seem that the tone also changes its intensity. Another example of interaction between analyzers is known fact increasing visual sensitivity with a weak taste of sour in the mouth. Knowing the patterns of changes in the sensitivity of the sensory organs, it is possible to sensitize a particular analyzer by using specially selected side stimuli. Sensitization can also be achieved as a result of exercise. These data have important practical applications, for example, in cases where it is necessary to compensate for sensory defects (blindness, deafness) at the expense of other, intact analyzers or in the development of pitch hearing in children involved in music.

Thus, the intensity of sensations depends not only on the strength of the stimulus and the level of adaptation of the receptor, but also on the stimuli currently acting on other sense organs. A change in the sensitivity of the analyzer under the influence of irritation of other sense organs is called interaction of sensations. The interaction of sensations, like adaptation, appears in two opposite processes: an increase and a decrease in sensitivity. Weak stimuli, as a rule, increase, and strong ones decrease, the sensitivity of analyzers

The interaction of analyzers is also manifested in the so-called synesthesia . With synesthesia, the sensation occurs under the influence of irritation characteristic of another analyzer. Visual-auditory synesthesia most often occurs when visual images (“color hearing”) appear under the influence of auditory stimuli. Many composers possessed this ability - N.A. Rimsky-Korsakov, A.N. Scriabin et al. Auditory-gustatory and visual-gustatory synesthesia, although they are much less common, we are not surprised by the use in speech of expressions like: “sharp taste”, “sweet sounds”, “screaming color”, etc.

5. Disorders of sensations

Sensory disturbances are very numerous. However, in most cases, all observed sensation disorders can be classified into one of three main groups: hyperesthesia, hypoesthesia and paresthesia.

Hyperesthesia - increased sensitivity to real ordinary or even weak influences. In these cases, both external and intero- and proprioceptive stimuli cause an extremely intense reaction due to a sharp decrease in the lower absolute thresholds of sensations. For example, the sound of a typewriter deafens the patient (acoustic hyperesthesia), a burning candle blinds (optical hyperesthesia), and a shirt adjacent to the body irritates so much that it seems to be made “of barbed wire” (hyperesthesia of the skin sense), etc. Such mental hyperesthesia is observed in neuroses, intoxication with certain substances, in the initial stages of clouding of consciousness, and in acute psychoses.

Hypesthesia - decreased sensitivity to real stimuli, increased lower absolute thresholds of sensations. In this case, the patient almost does not react to an injection, to a fly crawling on his face, etc. Reduced sensitivity to temperature stimuli can lead to accidents - burns and frostbite. In extreme cases of hypoesthesia, the analyzer is completely unable to respond to stimulation, and this phenomenon is called anesthesia. Anesthesia usually occurs with a complete anatomical interruption of one of the peripheral nerve trunks or destruction of the central part of the analyzer. Loss of sensation usually extends to tactile, pain and temperature sensitivity (total anesthesia) or only to certain types of it (partial anesthesia). Neurologists distinguish radicular anesthesia, in which sensitivity in the zone of innervation of a certain dorsal root of the spinal cord is completely impaired, and segmental, in which disorders occur in the innervation zone of a certain segment of the spinal cord. In the latter case, anesthesia can be as follows: total, so dissociated, in which the absence of pain and temperature sensitivity is combined with the preservation of proprioceptive sensitivity or vice versa. In some diseases, such as leprosy (leprosy), specific damage to skin receptors occurs with a subsequent weakening and loss of temperature, then pain, and then tactile sensitivity (proprioceptive sensitivity is preserved for the longest time during leprosy anesthesia).

At mental hypoesthesia and anesthesia the corresponding analyzer is anatomically and physiologically formally preserved. Thus, hypoesthesia and anesthesia can be instilled in a person in a hypnotic sleep. Mental amblyopia (blindness), mental anosmia (insensitivity to smells), mental ageusia (loss of the sense of taste), mental acusia (deafness), mental tactile and pain anesthesia are often found in hysterical neurotic disorders. Within the framework of hysterical anesthesia, disorders of pain sensitivity of the “stockings” and “gloves” type are described, i.e., from the point of view of neurologists, patients develop areas of insensitivity to pain with clear boundaries that do not correspond to the zones of innervation of certain roots or nerves.

Paresthesia . If hypoesthesia and hyperesthesia can be qualified as quantitative disorders of sensitivity, then paresthesia is associated with qualitative changes (distortion) of information coming from the receptor to the cortical part of the analyzer. Probably everyone knows about the sensations that arise from prolonged compression of a nerve by an uncomfortable position - “I rested my arm,” “I spent my time on my leg.” When conduction along the nerve is disrupted, sensations of “crawling goosebumps”, skin tightening, tingling, burning appear (these are peculiar fluctuations in the modality of sensation). Paresthesia is often a sign of neurological or vascular damage.

They are close to paresthesia and senesthopathy, but occupy an intermediate position with visceral hallucinations, since they are even less associated with any real irritation of the peripheral part of the analyzer.

Senestopathies, “psychosomatic sensations”, or “sensations” - vague, often migrating, very unpleasant and painful sensations that are projected inside the body (inside the bodily “I”): squeezing and stretching, rolling and trembling, “suction”, “sticking” etc. They never have a clear localization, and patients are not even able to describe them correctly. Senestopathies occur in many mental illnesses. They can be constant or episodic. Sometimes they occur in the form of attacks, acute attacks, which allows us to talk about senestopathic crises. They are often accompanied by panic reactions, autonomic disorders, fear of madness, expressive postures and gestures. Exist different approaches to assess the clinical significance of senestopathy and their classification. So, A.K. Anufriev (1978) distinguishes five types of senestopathy for latent depression: cardiovascular, central neurological, abdominal, musculoskeletal, and skin-subcutaneous.

List of used literature

1. Ananyev B.G. Theory of sensations. – L.: Lenizdat, 1961.

2. Luria A.R. Sensation and perception. – M.: Education, 1978.

3. Sidorov P.I., Parnyakov A.V. Clinical psychology. – 3rd ed., revised. and additional – M.: GEOTAR-Media, 2008.

And the person’s emotions? It is this issue that we decided to devote today’s article. After all, without these components we would not be people, but machines that do not live, but simply exist.

What are the sense organs?

As you know, a person learns all the information about the world around him through his own. These include the following:

• eyes;
• language;
• leather.

Thanks to these organs, people feel and see the objects around them, as well as hear sounds and taste. It should be noted that this is not a complete list. Although it is usually called the main one. So what are the feelings and sensations of a person who has functioning not only of the above organs, but also of other organs? Let's consider the answer to the question posed in more detail.

Eyes

The sensations of vision, or rather color and light, are the most numerous and diverse. Thanks to the presented body, people receive about 70% of information about the environment. Scientists have found that the number of visual sensations (of various qualities) of an adult, on average, reaches 35 thousand. It should also be noted that vision plays a significant role in the perception of space. As for the sensation of color, it completely depends on the length of the light wave that irritates the retina, and the intensity depends on its amplitude or so-called scope.

Ears

Hearing (tones and noises) gives a person approximately 20 thousand different states of consciousness. This sensation is caused by air waves that come from the sounding body. Its quality depends entirely on the magnitude of the wave, its strength on its amplitude, and its timbre (or sound coloring) on ​​its shape.

Nose

The sensations of smell are quite varied and very difficult to classify. They occur when the upper part of the nasal cavity, as well as the mucous membrane of the palate, is irritated. This effect occurs due to the dissolution of the smallest odorous substances.

Language

Thanks to this organ, a person can distinguish different tastes, namely sweet, salty, sour and bitter.

Leather

Tactile sensations are divided into feelings of pressure, pain, temperature, etc. They occur during irritation of nerve endings located in tissues, which have a special structure.

What feelings does a person have? In addition to all of the above, people also have feelings such as:

• Static (body position in space and a sense of its balance). This feeling occurs during irritation of the nerve endings that are located in the semicircular canals of the ear.
• Muscular, joint and tendon. They are very difficult to observe, but they are of the nature of internal pressure, tension and even slip.
• Organic or somatic. Such feelings include hunger, nausea, sensations of breathing, etc.

What are the feelings and emotions?

Emotions and inner feelings a person’s attitude to any event or situation in life. Moreover, the two named states are quite different from each other. So, emotions are a direct reaction to something. This happens at the animal level. As for feelings, this is a product of thinking, accumulated experience, experiences, etc.

What feelings does a person have? It is quite difficult to answer the question posed unambiguously. After all, people have a lot of feelings and emotions. They give a person information about needs, as well as feedback on what is happening. Thanks to this, people can understand what they are doing right and what they are doing wrong. After realizing the feelings that have arisen, a person gives himself the right to any emotion, and thereby he begins to understand what is happening in reality.

List of basic emotions and feelings

What are the feelings and emotions of a person? It is simply impossible to list them all. In this regard, we decided to name only a few. Moreover, they are all divided into three different groups.

Positive:

• pleasure;
• jubilation;
• joy;
• pride;
• delight;
• confidence;
• confidence;
• Delight;
• sympathy;
• love (or affection);
• love (sexual attraction to a partner);
• respect;
• gratitude (or appreciation);
• tenderness;
• complacency;
• tenderness;
• gloat;
• bliss;
• feeling of satisfied revenge;
• feeling of self-satisfaction;
• feeling of relief;
• anticipation;
• feeling of security.

Negative:

Neutral:

• astonishment;
• curiosity;
• amazement;
• calm and contemplative mood;
• indifference.

Now you know what feelings a person has. Some to a greater extent, some to a lesser extent, but each of us has experienced them at least once in our lives. Negative emotions that are ignored and not recognized by us do not just disappear. After all, the body and soul are one, and if the latter suffers for a long time, then the body takes on some part of its heavy burden. And it’s not for nothing that they say that all diseases are caused by nerves. Influence negative emotions on human well-being and health has long been scientific fact. As for positive feelings, the benefits of them are clear to everyone. After all, experiencing joy, happiness and other emotions, a person literally consolidates in his memory the desired types of behavior (feelings of success, well-being, trust in the world, people around him, etc.).

Neutral feelings also help people express their attitude towards what they see, hear, etc. By the way, such emotions can act as a kind of springboard to further positive or negative manifestations.

Thus, by analyzing his behavior and attitude to current events, a person can become better, worse, or remain the same. It is these properties that distinguish people from animals.

Sensation is one of the simplest and at the same time important psychological processes that signal what is happening at a given moment in time in the environment around us and in our own body. It gives people the opportunity to navigate the conditions that surround them and connect their actions and actions with them. That is, sensation is cognition environment.

Feelings - what are they?

Sensations are a reflection of certain properties that are inherent in an object, with their direct impact on human or animal senses. With the help of sensations, we gain knowledge about objects and phenomena, such as, for example, shape, smell, color, size, temperature, density, taste, etc., we capture various sounds, comprehend space and make movements. Sensation is the primary source that gives a person knowledge about the world around him.

If a person were deprived of absolutely all senses, then he would not be able to understand the environment by any means. After all, it is sensation that gives a person the material for the most complex psychological processes, such as imagination, perception, thinking, etc.

For example, those people who are blind from birth will never be able to imagine what blue, red or any other color looks like. And a person who has been deaf since birth has no idea what his mother’s voice, the purr of a cat or the babbling of a stream sounds like.

So, sensation is in psychology what is generated as a result of irritation of certain sense organs. Then irritation is an effect on the sense organs, and irritants are phenomena or objects that in one way or another affect the sense organs.

Sense organs - what are they?

We know that sensation is a process of cognition of the environment. And with the help of what do we feel, and therefore understand the world?

Also in ancient Greece identified five sense organs and sensations corresponding to them. We have known them since school. These are auditory, olfactory, tactile, visual and gustatory sensations. Since sensation is a reflection of the world around us, and we use not only these senses, modern science has significantly increased information about the possible types of feelings. In addition, the term “sense organs” today has a conditional interpretation. “Sensation organs” is a more accurate name.

The endings of the sensory nerve are main part any sense organ. They are called receptors. Millions of receptors have sensory organs such as the tongue, eye, ear and skin. When a stimulus acts on a receptor, a nerve impulse occurs and is transmitted along sensory nerve to certain areas of the cerebral cortex.

In addition, there is sensory experience that is generated internally. That is, not as a result of physical impact on the receptors. Subjective sensation is such an experience. One example of this sensation is tinnitus. In addition, the feeling of happiness is also a subjective feeling. Thus, we can conclude that subjective sensations are individual.

Types of sensations

In psychology, sensation is a reality that affects our senses. Today, there are about two dozen different sensory organs that reflect the impact on the human body. All types of sensations are the result of exposure to various stimuli on the receptors.

Thus, sensations are divided into external and internal. The first group is what our senses tell us about the world, and the second is what our own body signals to us. Let's look at them in order.

External senses include visual, gustatory, olfactory, tactile and auditory.

Visual sensations

This is a feeling of color and light. All objects that surround us have some color, while a completely colorless object can only be one that we cannot see at all. There are chromatic colors - various shades of yellow, blue, green and red, and achromatic - these are black, white and intermediate shades of gray.

As a result of the influence of light rays on the sensitive part of our eye (the retina), visual sensations arise. There are two types of cells in the retina that respond to color - rods (about 130) and cones (about seven million).

The activity of cones occurs only during the daytime, but for rods, on the contrary, such light is too bright. Our vision of color is the result of the work of cones. At dusk, rods become active, and a person sees everything in black and white. By the way, this is where famous expression that at night all cats are gray.

Of course, the less light, the worse person sees. Therefore, in order to prevent unnecessary eye strain, it is strongly recommended not to read at dusk or in the dark. Such strenuous activity has a negative impact on vision and may lead to the development of myopia.

Auditory sensations

There are three types of such sensations: musical, speech and noise. In all these cases, the auditory analyzer identifies four qualities of any sound: its strength, pitch, timbre and duration. In addition, he perceives the tempo-rhythmic features of sounds perceived sequentially.

Phonemic hearing is the ability to perceive speech sounds. Its development is determined by the speech environment in which the child is raised. Well-developed phonemic awareness significantly influences the accuracy of written speech, especially during training in primary school, whereas a child with poorly developed phonetic hearing makes many mistakes when writing.

A baby’s musical ear is formed and develops in the same way as speech or phonemic hearing. The early introduction of a child to musical culture plays a huge role here.

A certain emotional state of a person can create various noises. For example, the sound of the sea, rain, howling wind or rustling leaves. Noises can serve as a signal of danger, such as the hiss of a snake, the noise of an approaching car, or the menacing barking of a dog, or they can signal joy, such as the thunder of fireworks or the footsteps of a loved one. School practice often talks about the negative impact of noise - it tires nervous system schoolboy.

Skin sensations

Tactile sensation is the sensation of touch and temperature, that is, the feeling of cold or warmth. Each type of nerve endings located on the surface of our skin allows us to feel the temperature of the environment or touch. Of course, the sensitivity of different areas of the skin varies. For example, the chest, lower back and abdomen are more susceptible to the feeling of cold, and the tip of the tongue and fingertips are most susceptible to touch; the back is least susceptible.

Temperature sensations have a very pronounced emotional tone. Thus, a positive feeling is accompanied by average temperatures, despite the fact that the emotional colors of heat and cold differ significantly. Warmth is regarded as a relaxing feeling, while cold, on the contrary, is invigorating.

Olfactory sensations

Olfaction is the ability to sense smells. In the depths of the nasal cavity there are special sensitive cells that help recognize odors. Olfactory sensations modern man play a relatively small role. However, for those who are deprived of any sense organ, the rest work more intensely. For example, deaf-blind people are able to recognize people and places by smell and receive signals of danger using their sense of smell.

The sense of smell can also signal to a person that danger is nearby. For example, if there is a smell of burning or gas in the air. The emotional sphere of a person is influenced by big influence the smells of the objects around him. By the way, the existence of the perfume industry is entirely determined by the aesthetic need of a person for pleasant smells.

The senses of taste and smell are closely related to each other, since the sense of smell helps determine the quality of food, and if a person has a runny nose, then all the dishes offered will seem tasteless to him.

Taste sensations

They arise due to irritation of the taste organs. These are the taste buds, which are located on the surface of the pharynx, palate and tongue. There are four main types of taste sensations: bitter, salty, sweet and sour. A series of shades that arise within these four sensations gives the taste originality to each dish.

The edges of the tongue are sensitive to sour, its tip to sweet, and its base to bitter.

It should be noted that taste sensations are significantly influenced by the feeling of hunger. If a person is hungry, then tasteless food seems much more pleasant.

Internal sensations

This group of sensations lets a person know what changes are occurring in his own body. Interoceptive sensation is an example of an internal sensation. It tells us that we experience hunger, thirst, pain, etc. In addition, there are also motor, tactile sensations and a sense of balance. Of course, interoceptive sensation is an extremely important ability for survival. Without these sensations, we would know nothing about our own body.

Motor sensations

They determine that a person feels the movement and position in space of parts of his body. With the help of the motor analyzer, a person has the ability to feel the position of his body and coordinate its movements. Receptors of motor sensations are located in the tendons and muscles of a person, as well as in the fingers, lips, and tongue, because these organs need to make subtle and precise working and speech movements.

Organic sensations

This type of sensation tells us how the body works. Inside organs, such as the esophagus, intestines and many others, there are corresponding receptors. While a person is healthy and well-fed, he does not feel any organic or interoceptive sensations. But when something is disrupted in the body, they manifest themselves in full. For example, abdominal pain appears if a person has eaten something that is not very fresh.

Tactile sensations

This type of feeling is caused by the fusion of two sensations - motor and skin. That is, tactile sensations appear when you feel an object with a moving hand.

Equilibrium

This sensation reflects the position that our body occupies in space. In the labyrinth of the inner ear, which is also called the vestibular apparatus, when the body position changes, lymph (a special fluid) oscillates.

The organ of balance is closely related to the work of other internal organs. For example, with strong stimulation of the balance organ, a person may experience nausea or vomiting. This is otherwise called air sickness or seasickness. Stability of the balance organs during regular training increases.

Painful sensations

The feeling of pain has a protective value, as it signals that something is wrong in the body. Without this type of sensation, a person would not even feel serious injuries. The anomaly is considered complete insensitivity to pain. It does not bring anything good to a person, for example, he does not notice that he is cutting his finger or putting his hand on a hot iron. Of course, this leads to permanent injuries.

A brief excursion into the development of the concept of sensations

Feel- “the law of specific energy of the sensory organ,” that is, the 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, partial image of the world. Everything we perceive is a process of specificity of influence on the senses. “Mental processes” Wekker L.M.

Power-law dependence of changes in sensations when the intensity of stimuli changes (Stevens' law)

The lower and upper absolute thresholds of sensation (absolute sensitivity) and thresholds of discrimination (relative sensitivity) characterize the limits of human sensitivity. Along with this, there is a distinction operational sensation thresholds— the magnitude of the difference between the signals at which the accuracy and speed of their discrimination reaches a maximum. (This value is an order of magnitude greater than the discrimination threshold.)

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

Thus, when entering a poorly lit room, we initially do not distinguish objects, but gradually the sensitivity of the analyzer increases; being in a room with any odors, after a while we stop noticing these odors (the sensitivity of the analyzer decreases); when we move from a poorly lit space to 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 current stimulus is called adaptation(from lat. adaptatio- device).

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

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

The phenomenon of adaptation has a purposeful biological significance. It helps to reflect weak stimuli and protects analyzers from excessive exposure to strong ones. Adaptation, as getting used to constant conditions, provides an increased orientation to all new influences. Sensitivity depends not only on the strength 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 explained by 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 influence, its significance, a special attitude towards distinguishing between stimuli; 4) exercise, experience (thus, tasters, by specially exercising their taste and olfactory sensitivity, distinguish between different types of wines and teas and can even determine when and where the product was made).

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

Strong stimulation of some analyzers always reduces the sensitivity of others. This phenomenon is called desensitization. So, increased level noise in “loud workshops” reduces visual sensitivity; desensitization of visual sensitivity 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 sequential contrasting influences.

4. . One of the manifestations of the interaction of sensations is their contrast(from lat. contrast- sharp contrast) - increased sensitivity to some properties under the influence of other, opposite, properties of reality. Thus, the same gray figure appears dark on a white background, but white on a black background (Fig. 4).

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

Rice. 5.

Features of certain types of sensations.

Visual sensations. Colors perceived by humans are divided into chromatic (from the Greek. chroma- color) and achromatic - colorless (black, white and intermediate shades of gray).

For visual sensations to occur, exposure is necessary. electromagnetic waves to the visual receptor - the retina (a collection of photosensitive nerve cells located at the bottom of the eyeball). The central part of the retina is dominated by nerve cells called cones, which provide the sense of color. At the edges of the retina, rods, sensitive to changes in brightness, predominate (Fig. 5, 6).

Rice. 6. . Light penetrates the light-sensitive receptors - rods (reacting to changes in brightness) and cones (reacting to different lengths of electromagnetic waves, i.e. chromatic (color) influences), bypassing the ganglion and bipolar cells, which carry out the primary elementary analysis of nerve impulses traveling already from the retina. For visual stimulation to occur, it is necessary that the electromagnetic energy falling on 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 - an electroretinograph.

Light (electromagnetic) rays of different lengths cause different color sensations. Color is a mental phenomenon - human sensations caused by different frequencies electromagnetic radiation(Fig. 7). The eye is sensitive to the region of the electromagnetic spectrum from 380 to 780 nm (Fig. 8). The 680 nm wavelength gives the sensation 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 color. Any color can be obtained by mixing two bordering colors. For example: red - a mixture of orange and purple).

The mixing of all perceived electromagnetic waves gives the sensation of white color.

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

Rice. 10. .

Our eye is sensitive to different parts of the electromagnetic spectrum 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 in twilight conditions moves towards shorter waves - 500 nm ( Blue colour). 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 are turned on and the rod apparatus is turned off. In low light conditions, only the sticks are activated. Therefore, in twilight lighting we do not distinguish chromatic color, the coloring 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. Redistribution of information from each eye occurs as a result of the crossing of part of the optic nerve fibers in the chiasm.

Visual stimulation is characterized by some inertia. This is the reason for the persistence of a trace of light stimulation after the cessation of exposure to the stimulus. (This is why we do not notice the breaks 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 disadvantage, described by the English physicist D. Dalton, is called color blindness). Weakening of the rod apparatus makes it difficult to see objects in dim light (this deficiency 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 contrasts is possible through the use of various means. (To identify subtle relief, shadow contrast is enhanced by lateral lighting and the use of light 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 red, which are reflected by it.) The color of transparent objects is characterized by the rays that they transmit. Thus, the color of any object depends on what rays it reflects, absorbs and transmits.

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

In most cases, objects reflect electromagnetic waves of different lengths. But the visual analyzer does not perceive them separately, but collectively. 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) arrive to 1 million larger (ganglionic) neurons of the retina. Each ganglion cell sends its process (axon) to the optic nerve. Impulses traveling to the brain along the optic nerve receive primary processing in diencephalon. Here the contrast characteristics of the signals and their time sequence are enhanced. And from here, nerve impulses enter the primary visual cortex, localized in the occipital region of the cerebral hemispheres (Brodmann fields 17 - 19) (Fig. 11, 12). Here, individual elements of the visual image are highlighted - points, angles, lines, directions of these lines. (Established by Boston researchers, laureates Nobel Prize for 1981 by Hubel and Wiesel.)

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

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

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

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

The work of the auditory analyzer is no less complex and important than the work of the visual analyzer. The main flow of speech information goes through this channel. A person perceives a sound 35 - 175 ms after it reaches auricle. Another 200 - 500 ms is necessary for maximum sensitivity to a given sound to occur. It also takes time to turn the head and appropriately orient the auricle in relation to the source of the 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 enhanced (due to 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. The eardrum 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 eardrum.) In the middle ear, sound is amplified many times over by a system of ossicles (the malleus, incus and stapes). These ossicles are supported 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 sound intensity in the middle ear increases 30 times due to the difference between the area of ​​the eardrum (90 mm2), to which the malleus is attached, and the area of ​​the base of the stapes (3 mm2).

Rice. 15. . Sound vibrations from the external environment pass through the ear canal to the eardrum, located between the outer and middle ear. The eardrum 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, slight changes in pressure at the eardrum are transmitted in a piston-like motion to the oval window of the inner ear, which causes fluid movement 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, or more precisely, a certain part of it that resonates at the corresponding 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 extending from it serve to equalize pressure with the external environment; entering the nasopharynx area, 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 section of the auditory system is 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 fluid (perilymph). Along the membrane, which narrows from the lower curl of the cochlea to its upper curl, there are 30 thousand sensitive formations - cilia - they are sound receptors, forming the so-called organ of Corti. The primary separation of sound vibrations occurs in the cochlea. Low sounds affect long cilia, 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 humans 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 vibrations of the sound source and on the pitch of the sound. The pitch of the sound is determined by the frequency of vibrations of the sound wave, the timbre of the sound is determined by overtones (additional vibrations in each main phase) (Fig. 16).

The pitch of a sound is determined by the number of vibrations of the sound source in 1 second (1 vibration per second is called a hertz). The organ of hearing is sensitive to sounds in the range from 20 to 20,000 Hz, but the greatest 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 begins at 16 Hz.

Rice. 16. . The intensity of a sound is determined by the amplitude of the vibration of its source. Height - vibration frequency. Timbre - additional vibrations (overtones) in each “time” (middle picture).
However, subthreshold low-frequency sounds affect a person’s mental state. Thus, sounds with a frequency of 6 Hz cause dizziness, a feeling of fatigue, depression in a person, 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 suggestibility, learning ability, etc.

Sensitivity to high-frequency sounds in humans is limited to 20,000 Hz. Sounds lying beyond the upper threshold of sound sensitivity (i.e. above 20,000 Hz) are called ultrasounds. (Animals have access to ultrasonic frequencies of 60 and even 100,000 Hz.) However, since sounds up to 140,000 Hz are found in our speech, it can be assumed 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 of sensitivity to sound intensity. With age, sound sensitivity decreases. Thus, to perceive speech at the age of 30, a sound volume of 40 dB is required, and to perceive speech at the age of 70, its volume must be at least 65 dB. The upper threshold of hearing sensitivity (in terms of volume) is 130 dB. Noise above 90 dB is harmful to humans. Sudden loud sounds that hit the autonomic nervous system and lead to a sharp narrowing of the lumen of blood vessels, increased heart rate and an increase in the level of adrenaline in the blood are also dangerous. The optimal level is 40 - 50 dB.

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

Rice. 17. .

The threshold of spatial tactile sensitivity is the minimum distance between two point touches at which these impacts are perceived separately. The range of tactile discrimination sensitivity is from 1 to 68 mm. High sensitivity zone - from 1 to 20 mm. Low sensitivity zone - from 41 to 68 mm.

Tactile sensations combined with motor ones form tactile sensitivity, which underlies objective actions. Tactile sensations are a type of skin sensation, which also includes temperature and pain sensations.

Kinaesthetic (motor) sensations.

Rice. 18. (according to Penfield)

Actions are associated with kinesthetic sensations (from the Greek. kineo- movement and aesthesia- sensitivity) - sensation of the position and movement of parts of one’s own body. Labor movements of the hand were of decisive importance in the formation of the brain and the human psyche.

Based on muscle-joint sensations, a person determines compliance or non-compliance
their movements to external circumstances. Kinaesthetic sensations perform an integrating function throughout the human sensory system. Well-differentiated voluntary movements are the result of the analytical and synthetic activity of a large cortical zone located in the parietal region of the brain. The 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 driving various parts 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 appropriate correction of movement. As a result of training, images of intermediate positions of various parts of the body are generalized into a single general model of a specific action - the action is stereotyped. All movements are regulated based on motor sensations, based on feedback.

Motor physical activity The body is essential for optimizing brain function: proprioceptors of skeletal muscles send stimulating impulses to the brain and increase the tone of the cerebral cortex.

Rice. 20.: 1. Limits of permissible vibrations for individual parts of the body. 2. Limits of permissible vibrations acting on the entire human body. 3. Boundaries 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 the rotational movement accelerates or decelerates, the fluid filling the semicircular canals exerts pressure (according to the law of inertia) on the sensitive hairs, in which a corresponding excitation is caused.

Moving into space in a straight line reflected in otolithic apparatus. It consists of sensitive cells with hairs, above which are located otoliths (pads with crystalline inclusions). Changing the position of the crystals signals the brain the direction of the rectilinear movement of the body. The semicircular canals and otolithic apparatus are called vestibular apparatus. It is connected to the temporal region of the cortex and to 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 internal organs.)

Vibration sensations arise as a result of reflection of vibrations 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 humans. 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 of the mucous membrane of the nasal cavity, where the olfactory cells are located.
Substances that irritate the olfactory receptors penetrate into the nasopharyngeal cavity from the nose and nasopharynx (Fig. 21). This allows you to determine the smell of a substance both from a distance and if it is in the mouth.

Rice. 22. . Relative concentration of taste receptors on the surface of the tongue.

Taste sensations. The entire 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 unevenly on the surface of the tongue. Certain areas of the surface of the tongue are most sensitive to individual 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 participates in the formation of tactile sensations (the consistency of food affects taste sensations).

Temperature sensations arise from irritation of skin thermoreceptors. 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 areas of the skin themselves have different temperatures (Fig. 23).

Painful sensations are caused by mechanical, temperature and chemical influences that have reached above-threshold intensity. Pain sensations are largely associated with subcortical centers, which are regulated by the cerebral cortex. Therefore, they can be inhibited to some extent through a second signaling 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 warmth reduces pain. Pain, temperature, tactile sensations and pressure sensations are skin sensations.

Organic sensations- sensations associated with interoceptors 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 C.S. Sherrington (1906);

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

Cognition of the environment and one’s own states begins in a person with such a mental process as sensation. It is sensations that allow a person to navigate the environment, distinguish sounds, colors, smells, taste of products, and also estimate the weight and size of objects. However, sensation is not capable of giving a person a complete picture of the reflected objects. With the help of sensations Living being is able to gain knowledge about the individual properties of certain objects.

V.M. Kozubovsky gives the following definition: “Sensation is a mental cognitive process of reflecting individual properties of the real outside world and the internal state of a person, which directly affect the senses at a given (current) moment. When sensing, primary information processing occurs precisely at the sensory level, that is, at the level of individual properties of objects and phenomena.”

It is worth noting that sensations are characteristic of all living beings that have a nervous system. Sensations are a sensory reflection of objective reality, as they arise due to the influence of various stimuli on the sense organs. It is precisely in the fact that a really existing external stimulus is reflected through the means of sensations that the objectivity of sensations is expressed. However, sensations are also characterized by subjectivity, which is due to the dependence of sensations on individual characteristics and the current mental state of a person.

Physiological basis sensations are analyzers, that is, channels through which a person receives information about the external environment and his own internal state. Together, the analyzers form the human sensory system.

Feelings begin with physical process irritation, which occurs when various factors influence the human senses: vision, smell, etc. The appearance of sensations directly depends on the functioning of the brain, however, in order for the brain to perceive certain stimuli, they must be transmitted to it in the form of electrical signals. Translation of signals of various modalities into electrical form is carried out using receptors.

Each receptor works with certain signals: the visual one reacts to light stimuli, the auditory one to sound stimuli, etc. In this case, not only information about the presence of the stimulus is transmitted to the brain, but also about its characteristics. Coding of signal characteristics is realized through the conversion of physical stimuli into electrical signals with certain parameters. So, for example: the sensation of touching the hand corresponds to a sequential series of rectangular electrical impulses, while a light touch corresponds to a small number of impulses in a series, strong pressure - a large number of.

After encoding, the electrical signal enters the receptive zones of the cerebral cortex via afferent nerves, with each receptor having a specific receptive zone. The movement of signals is ensured by the physiological process of excitation - the property of nerve cells (neurons) to respond to irritation. When excited, the cell moves from a state of physiological rest to activity.

In the cerebral cortex, an electrical signal causes the simplest emotional experiences of sensations that arrive at the periphery of the body through excitation through efferent nerves. Thus, a response of the body occurs, which can take the form of movement or an internal process.

For example, birdsong and the sound of the sea surf balance the nervous system and promote relaxation. The body also reacts to the sensations of smells. The Japanese company Shieido successfully uses odors to increase the stress resistance of their employees. On the website “World of Psychology and Self-Development” you can study in more detail such areas in psychology as color therapy, music therapy and aromatherapy.

In psychology, the following properties of sensations are distinguished:

1. Intensity of sensation characterizes a person’s subjective sensory experience and expresses the degree of sensation experienced, which depends on the strength of the stimulus and the functional state of the receptor.
2. Duration of sensation - this is the period of time during which the sensation of the impact of the stimulus persists after its cessation.
3. Latent (hidden) period of sensation - the period of time from the moment the stimulus begins to act until the moment the sensation begins.
4. Aftereffect of sensation - the period of time from the end of the stimulus until the sensation disappears. So, due to the aftereffect of sensations, we do not notice breaks between frames when watching a film.
5. Spatial localization of the stimulus - the property of sensation to provide a person with the ability to determine the spatial position of the stimulus acting on the receptors (the direction of the sound, the location of the pain point on the body, etc.)

Sensations are classified according to their characteristics, that is, depending onwhat properties need to be emphasized:

- by type of modality (visual, auditory, olfactory, skin and taste sensations);

— according to the level of awareness, they are divided into conscious and unconscious (for example, sensations of balance);

- Based on the location of the receptors, interoceptive, exteroceptive and proprioceptive are distinguished.

Interoceptive sensations– these are sensations that signal the state of the internal processes of the body and are associated with internal receptors located on the walls of the internal organs (feelings of hunger, thirst, pain, etc.)

Information from the external environment of a person is provided exteroceptive sensations, which arise both through direct contact with a source of irritation (contact), and through a source located at some distance (distant). It is worth noting that olfactory sensations are sometimes neutral, since the source of the odor is located at a distance, and the molecules carrying the odor have direct contact with human receptors.

There are other classifications of sensations. It is interesting that in psychology the prevailing hypothesis is the existence of a magnetic sensation, which helps some species of animals (dolphins, pigeons, bees, etc.) navigate in the Earth’s magnetic field.

In the following articles you will learn more about different types sensations.