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Features of interoceptive sensations. Types of sensations and their mechanisms. General concept of sensation

The editors of the American journal "Journal of Minerals, Metals and Materials Society" (by the way, this is one of the best interdisciplinary scientific journals in materials science) decided to celebrate the fiftieth anniversary of the Minerals, Metals and Materials Society with an interesting event. With the help of readers as well as respected members of the community, a list of one hundred of the most important events and people who have had a significant impact on the development of the science of structural and special materials has been prepared. This list was published in the October issue of the magazine and posted on the Internet at www.materialmoments.org. It is assumed that until January 5, 2007, everyone can vote for those events that seem to him the most important. The ten events with the most votes will then be reviewed by a council of former and current society presidents and selected as the one that the materials science community considers most important in the history of its science. What kind of event this is - everyone will find out on February 26, 2007 during the annual meeting of the society.

With the kind permission of the organizers, "Chemistry and Life", which is by no means alien to the problems of materials science, decided to join this action. We have translated the list of one hundred events into Russian and are publishing it in this issue, taking into account some identified errors and a slight reduction.

28 thousand years BC e. The oldest fired ceramics are figurines of animals and people, as well as balls and plates. Found during excavations of the Pavlovsk Hills in Moravia. Start of materials processing.

8 thousand years BC e. The beginning of metallurgy - Neolithic people began to forge jewelry from native copper. Stone tools were replaced by more reliable copper ones.

5 thousand years BC e. People who lived in Asia Minor discovered that liquid copper was obtained by firing malachite and lapis lazuli, and various figures could be cast from it. The beginning of metallurgy and the discovery of the Earth's interior as a storehouse of minerals.

3.5 thousand years BC e. The Egyptians first smelted iron (apparently as a by-product of refining copper) and began using it to make jewelry. The first secret of obtaining the main metal of civilization has been revealed.

3 thousand years BC e. Metallurgists in the Middle East and Asia Minor discovered that the addition of tin ore to copper ore produced a material much stronger than pure copper or tin—bronze. The concept of alloying emerged, the idea that a mixture of two or more metals produces a substance whose properties exceed those of each of the components.

2.2 thousand years BC e. Residents of Northwestern Iran made the first glass. The second (after ceramics) main non-metallic material of civilization appeared.

1.5 thousand years BC e. Chinese potters made the first porcelain from kaolin clay. This marked the beginning of a centuries-old tradition of making artistic masterpieces from this type of ceramic.

1.5 thousand years BC e. Middle Eastern metallurgists developed the technology of lost wax casting. The beginning of mass production of complex-shaped objects from metal.

300 BC Metallurgists in South India came up with a way to melt steel in cupola furnaces - ceramic vessels dug into the ground. The same steel was obtained, which centuries later would be called “Damascus” and the secret of obtaining which will remain a mystery for many generations of blacksmiths and metallurgists (until Anosov reveals it, we add).

200 BC e. Chinese metallurgists have mastered steel casting. This marked the beginning of a centuries-old tradition of producing metal products in China.

100 BC e. The inhabitants of the Middle East, most likely the Phoenicians, mastered glassblowing. It became possible to quickly make large, transparent and leak-free vessels.

400 AD e. Indian metallurgists erected an iron pillar seven meters high near Delhi. The pillar, which withstood 1,500 years of corrosion tests without consequences in the very aggressive atmosphere of this humid region, serves as a striking example of the triumph of materials science and remains an archaeological mystery.

1450 Johannes Gutenberg created an alloy of the lead-tin-antimony system from which typeset type could be cast in copper molds for printing. The technological basis of the media has been created.

1451 Johanson Funcken developed a method for separating silver from lead and copper, the ores of which are usually mixed. It has been established that metal mining and processing operations can produce the desired metal as a by-product.

1540 Vannoccio Biringuccio publishes the treatise "De la pirotechnia". The first guide to forging.

1556 George Agricola publishes the treatise "De re metallica". A systematic and beautifully illustrated guide to mining and metallurgy as they existed in the 16th century.

1593 Galileo Galilei publishes Della scienza mechanica, a treatise he prepared after serving as a consultant on shipbuilding. Guide to Strength of Materials.

1688 Anton van Leeuwenhoek developed an optical microscope with 200x magnification. The beginning of the study of structures invisible to the human eye.

1709 Abraham Derby I discovered that coke could be an excellent substitute for charcoal in the production of pig iron. The cost of iron decreased significantly, its large-scale production became possible, and Europe was saved from the complete disappearance of forests.

1750 Fish glue is patented in Britain - the first patented glue in the world. The beginning of the production of adhesives, both from natural and, later, from synthetic substances.

1755 John Smeaton created concrete. The emergence of the main building material of our time.

1805 Luigi Brugnatelli invented a method for applying electroplating. From here came the industrial methods of making coatings for both industrial and decorative purposes.

1807 Sir Humphry Davy developed the process of electrolysis to separate metals from salts, particularly potassium, calcium, strontium, barium and magnesium. The basis of electrometallurgy and electrochemistry has been created.

1816 Augustus Tavu developed an amalgam of mercury and silver coins for dental fillings. A cheap material has been obtained for filling holes in teeth - the first example of a metallic biomaterial.

1822 Augustin Cauchy gave a report on his theory of stress and strain to the French Academy of Sciences. The first scientific definition of stress as the load per unit cross-sectional area of a material is formulated.

1827 Friedrich Wöhler isolated aluminum metal by heating its chloride with potassium. The most common metal that makes up the earth's crust has been obtained in its pure form.

1827 Wilhelm Albert used steel rope to lift loads from a mine. Replacing hemp rope with a stronger material made it possible to significantly increase the lifting height and led to an exponential increase in the size of structures.

1844 Charles Goodyear invented a method for vulcanizing rubber. Rapid progress in many industries, from the manufacture of vehicles to electrical engineering.

1855 Georges Hadamard patented rayon made from fibers from the inner layer of mulberry bark. The first production of viscose began the era of artificial fibers, and subsequently opened up new areas of textile application. Textiles - a material structure consisting of woven threads, are used today both in technology and in everyday life, and it is unthinkable to imagine what would happen if suddenly all textiles disappeared in our world - a real catastrophe would happen and it would take a lot of time to replace it with something with the same properties. Clothing, shoes, industrial and household products, works of art, upholstery, decoration - you name it. Home textiles occupy a special place, providing comfort and ecology of life, and among them in Russia there is the outstanding textiles of Ivanovo - a huge and constantly improving variety of products.

1856 Henry Bessemer patented the acid converter process for producing mild steel. The beginning of the era of low-cost, high-tonnage steel production, fast development transport, construction and general industrialization.

1863 Emile and Pierre Martin developed the open-hearth process for melting steel. The beginning of large-scale production of general purpose steel from a mixture of scrap and iron ore - making steel a material that can be recycled more times than any other.

1863 Henry Clifton Sorby first used a light microscope to study the microstructure of steel. Beginning of the use of photomethods in metallurgy. (P.P.Anosov was the first to use a microscope to study the structure of steel in 1831, and L.Zh.M.Dager reported the discovery of the daguerreotype process in 1839. - Ed.)

1864 D.I. Mendeleev discovered the Periodic Table of Elements. An invaluable guide has been created, without which the work of a materials scientist is unthinkable.

1867 Alfred Nobel patented dynamite. Large-scale mining operations became possible.

1878 William Siemens patented the electric arc melting furnace. The basis for steel production in electric furnaces has been created.

1880 Pierre Manet built the first converter for copper smelting. The beginning of the modern stage of copper smelting production.

1886 Charles Martin Hall and Pierre Herod simultaneously and independently discovered a method for producing aluminum from its oxide by electrolysis. Aluminum has evolved from a precious exotic to a structural metal that can be produced on an industrial scale.

1890 Adolf Martens examined the microstructure of hard quenched steel and found that it differed from the structure of less hard steels: the grains were filled with needles and plates. Beginning of the use of the microscope to recognize crystal structures and establish the relationship between structure and properties.

1896 Pierre and Marie Curie discovered radioactivity. Research into spontaneous radiation began, and radioactive materials began to be used for peaceful and military purposes.

1898 William Roberts-Austen constructed a diagram of phase transformations for the iron-carbon system (in fact, the honor of discovering the critical points of these phase transformations belongs to K.V. Chernov, and he did this in 1868 - Ed. note). Work began on a thorough study of this most important phase diagram for metallurgy, and the basis was created for the development of similar diagrams for other systems. In terms of significance, this is comparable to the acquisition of writing, since phase diagrams for a metallurgist are the same as letters.

1900 Johan August Brinell figured out how to measure the hardness of metals by the size of the imprint of an indenter (steel ball or diamond pyramid) on the surface of the sample. A reliable and still used method for determining the hardness of almost any metal has emerged.

1901 Charles Vincent Potter developed a flotation process to separate sulfide minerals from gangue. Large-scale extraction of metals from increasingly poorer ores became possible.

1904 Léon Gillette developed the first stainless steel composition. Introducing the use of steel in highly corrosive environments.

1906 Alfred Wilm discovered that aluminum alloys are strengthened by the precipitation of fine particles. The first high-strength aluminum alloy appeared - duralumin.

1909 Leo Bakeland synthesized a solid thermoplastic polymer - bakelite, also known as phenol-formaldehyde resin. The beginning of the era of plastics and the emergence of the plastics industry.

1909 William D. Coolidge, using powder metallurgy, produced elastic tungsten wire suitable for use as a light source for an incandescent lamp. The rapid spread of light bulbs and the creation of powder metallurgy began.

1911 Kammerling Onnes discovered superconductivity while researching metals at ultra-low temperatures. The first step towards modern successes in the field of low- and high-temperature superconductivity and the creation of products based on them.

1912 Max von Laue discovered X-ray diffraction by crystals. A year later, independently of each other, Yu.V. Wulf and William Henry Bragg with their son William Lawrence derived the basic formula for X-ray diffraction analysis, the so-called Wulf-Bragg rule. Beginning of X-ray diffraction studies of crystalline materials.

1913 Niels Bohr published a model of the structure of the atom. A theory has emerged according to which electrons orbit in discrete orbits around
the central nucleus, and the chemical properties of the elements are determined by the number of electrons in the outer orbits.

1918 Jan Czochralski created a method for growing large single crystals of metals. Today, it is this method that is used to grow silicon single crystals for the semiconductor industry.

1920 Hermann Staudinger suggested that polymers are nothing more than long chains of similar units connected by covalent bonds. Polymer chemistry appeared.

1925 Werner Heisenberg created matrix mechanics, and Erwin Schrödinger created wave mechanics and introduced the nonrelativistic Schrödinger equation for atoms. The basis of quantum mechanics has been created.

1926 Wildo Lonsbury Samon created polyvinchloride. The emergence of the most common plastic construction material.

1926 Paul Merica patented the addition of small amounts of aluminum to a nickel-chromium alloy and produced the first high-temperature superalloy. It became possible to create engines for jet aircraft, rockets and powerful turbines of thermal power plants.

1927 Clinton Davisson and Lester Germer experimentally confirmed the wave nature of the electron. This work forms the basis of modern solid-state electronics.

1927 Arnold Sommerfeld applied quantum mechanics to Drude's theory of metals and created the theory of free electrons in metals. Signifies the emergence of a simple but close to reality model of the behavior of electrons in a crystal lattice, which served as the basis for the development of all subsequent physics solid.

1928 Fritz Pflumer patented magnetic tape. A technology was created that led to the emergence of various data storage devices from tapes to hard drives.

1932 Arne Olander discovered the shape memory effect of an alloy of gold and cadmium. Led to the development of numerous shape memory materials and their use in medicine and many fields of technology.

1933 Max Knohl and Ernst Ruska built the first transmission electron microscope. One more step has been taken into the structure of the metal.

1934 Egon Orowan, Michael Pogliani and G.I. Taylor, in three independent papers, proposed to explain the plasticity of metals by the nucleation and movement of dislocations. Creation of the basis of solid mechanics.

1935 Wallace Hume Carothers, Julian Hill and a group of other researchers patented nylon. This invention significantly reduced the need for
silk and ensured the rapid development of the polymer industry.

1937 Norman de Bruin developed the Gordon-Aerolite composite material, consisting of high-strength fibers in a phenolic resin matrix. The production of fiberglass began.

1937 Andre Guinier and G.D. Preston independently discovered diffusion bands in aging aluminum-copper alloys. It led to a better understanding of the mechanism of hardening of alloys due to the small particles released in them.

1939 Otto Hahn and Fritz Strassmann discovered the fission of a uranium nucleus when irradiated with neutrons. Served as the basis for the creation of nuclear energy and nuclear weapons.

1939 Rousset al Aul, George Southworth, Jack Skaff and Henry Tuerer discovered regions of electron and hole conductivity in silicon. Without this, it is unlikely that the first transistor would have been created eight years later.

1940 Wilhelm Knohl developed a cost-effective process for producing titanium. It has become possible to mass produce high-purity titanium and products made from it: from aircraft fuselages to corrosion-resistant reactor vessels.

1942 Frank Spedding developed an efficient process for producing high-purity uranium from its halides. Ensured the successful development of the atomic bomb.

1948 John Bardeen, Walter Brattain and William Shockley create the transistor. Appeared main element all microelectronics.

1951 Bill Pfan came up with a method for cleaning metals using zone melting. The emergence of technology that is now used to produce ultra-pure materials, such as semiconductors.

1952 Nick Holonyak Jr. develops the first light-emitting diode (LED) that emits near-visible light. The beginning of the use of alloys from elements of groups III and V of the periodic table in semiconductor devices, including heterostructures with heterojunctions and quantum walls.

1953 A group of Swedish scientists produced the first artificial diamonds. The emergence of the diamond industry, without which high-precision
processing of parts.

1954 Gerald Pearson, Deryl Chapin and Calvin Fuller developed the solar cell, the first device capable of converting sunlight into electricity. The emergence of solar energy, as well as technology for manufacturing photodetectors.

1956 Peter Hirsch and colleagues using an electron microscope confirmed the existence of dislocations in metals. Not only was the dislocation theory confirmed, but the power of electron microscopes was also demonstrated.

1958 Jack Kilby assembled capacitances, resistors, diodes and transistors on a single germanium substrate, creating a microcircuit. Creating the basis for all current high-speed computers and communications.

1958 Frank Wehr-Schneider developed a method for directed crystallization of turbine blades consisting of huge columnar crystals. This revolutionary solution has made it possible to significantly increase the operating temperature of jet engines, which provides airlines with significant fuel savings.

1959 Paul Duvets, using rapid cooling, obtained an amorphous gold-silicon alloy. Creation of the first metallic glass - a promising class of new materials.

1959 Richard Feynman gave his famous talk “There's a Lot of Free Space Below” at a meeting of the American Physical Society. The concept of nanotechnology was introduced.

1964 Stefania Kwolek created the high-strength, lightweight plastic Kevlar. Kevlar fibers are an indispensable component of modern composites, from which a huge number of things are made - from tires to body armor.

1965 Cambridge Instruments develops the first scanning microscope. A very advanced method for studying surfaces has appeared, the capabilities of which are many times greater than those of a light microscope.

1966 Karl Strnat and colleagues discovered magnetocrystalline anisotropy in cobalt compounds with rare earth metals. Creating extremely powerful permanent magnets based on samarium-cobalt systems, and later neodymium-iron-boron and their use in various devices.

1970 James Fergason, using the field effect of twisted nematics, created the first working liquid crystal display. The result has completely transformed a variety of products, from computer displays and televisions to medical devices.

1970 Bob Maurer, Peter Schulz and Donald Keck create an optical fiber through which light passes with low loss. Revolution in telecommunications.

1977 Hideki Shirakawa, Alan McDiarmid and Alan Heger discovered electrically conductive polymers. Creation of flat displays based on organic light-emitting diodes, efficient solar cells and optical photomultipliers.

1981 Heinrich Rohrer and Gerd Karl Binning created a tunnel scanning microscope. It became possible to examine the surface structure with atomic precision.

1985 Robert Curl Jr., Richard Smalley, and Harold Walter Croteau discovered that carbon atoms sometimes cluster into spheres of 60 atoms called "buckyballs" or "fullerenes." It was believed that carbon is capable of forming countless structures.

1986 Johann Bednorz and Karl Müller create high-temperature superconducting ceramics based on the yttrium-barium-copper-oxygen system. The possibility of large-scale use of superconducting materials has opened up.

1989 Don Eigler used a tunneling microscope to write the word "IBM" with xenon atoms. The possibility of manipulating individual atoms and creating nanostructures has been demonstrated.

1991 Sumio Iizima discovered carbon nanotubes. Another promising material has appeared, since nanotubes are a hundred times stronger than steel and weigh six times less. In addition, they have unusual thermal and electrical properties.

1991 Eli Yablonovitch made a photonic crystal that can stop light of a certain wavelength. This device is a regular crystal in which a system of holes is drilled. They trap the light. The basis for obtaining photonic transistors has been created.

News announcements

Interoceptive sensations

Interoceptive sensations, signaling the state of the internal processes of the body, arise due to receptors located on the walls of the stomach and intestines, the heart and circulatory system and other internal organs. This is the most ancient and elementary group of sensations. Receptors that perceive information about the state of internal organs, muscles, etc. are called internal receptors. Interoceptive sensations are among the most conscious and most diffuse sensations and always retain their proximity to emotional states.

Organic sensations

Organic sensitivity gives us a variety of sensations that reflect the life of the organism. Organic sensations include: sensations of hunger, thirst, sensations coming from the cardiovascular, respiratory and reproductive systems of the body, as well as difficult-to-differentiate sensations that form the sensory basis of good or bad general well-being.

Research in recent decades has led to the discovery of receptors in a wide variety of internal organs, the activity of which is associated with organic sensations. Interoceptors are located throughout the digestive tract, in all organs abdominal cavity, in the liver, spleen, lungs, heart, blood vessels. Interoceptors perceive stimuli of a mechanical, chemical and physico-chemical nature. Impulses coming from many different receptors located in the internal organs form the sensory basis of “general well-being” in a healthy state; in pathological cases they cause feelings of ill health, weakness, and depression.

The blood vessels of the heart are innervated by sensory nerves, and the receptors of the vessels can perceive both changes in pressure inside the vessels and changes in the chemical composition of the blood. The activity of these receptors is related to the sensation of headache and heaviness in the head.

Receptors in the digestive tract are essential for overall well-being and performance. The activities of the interoceptors of the digestive tract are associated with sensations of hunger and thirst. Hunger and the sensations that accompany it have been the subject of numerous studies. At first it was believed that the feeling of hunger was caused by an empty stomach. However, more careful observation, experimental and clinical facts have led to the conclusion that the feeling of hunger appears much later after the stomach has been emptied. In contrast to this peripheral theory of hunger, a theory was put forward that claims that the feeling of hunger is of central origin (M. Schiff). According to this theory, blood depleted during hunger, with its altered chemical composition, affects the brain, causing a feeling of hunger, which is then projected to the stomach area. However, there are objections to this theory. When explaining the feeling of hunger, it is impossible to ignore the activity of numerous receptors located in the gastric mucosa and in the smooth muscles of its walls. These receptors signal the system about the presence, quantity and nature of stomach contents. Irritations emanating from contractions of an empty stomach are transmitted to the brain through afferent nerves. The resulting feeling of hunger reflects in the mind the lack of nutrients in the body.

Thirst is expressed in sensations localized in the mouth, pharynx and upper esophagus. When thirst reaches great strength, these sensations are accompanied by compression of the pharynx, causing spasmodic sensations and convulsive swallowing movements. These local sensations are accompanied by a general painful feeling. With regard to thirst, as well as hunger, there is a struggle between the central theory, which explains thirst by the lack of water in the body, and the peripheral theories, which pay attention to peripheral manifestations - dryness of the larynx, etc. In reality, central and peripheral factors interact. The general lack of water in the body makes itself felt in the salivary glands, the secretion of which contains water. Lack of secretion of the salivary glands leads to dryness of the mouth and pharynx and, indirectly due to a lack of water in the body, increased and rapid contractions of the esophagus occur. Thus, the feeling of thirst also includes a feeling of tension.

The respiratory system gives us more or less sharp sensations when the automatic regulation of breathing is disrupted. The need for air that is not adequately satisfied is reflected in specific general and localized sensations of suffocation. General feelings are caused primarily by a violation of normal blood chemistry, local reflect impaired coordination of respiratory movements and muscle tension through which they are carried out. These sensations cause a tendency to restore normal breathing.

Feeling pain

Pain is a biologically important protective device. Occurring under the influence of irritations that are destructive in nature and strength, pain signals a danger to the body. Pain sensitivity is distributed unevenly on the surface of the reins and in the internal organs. On average, according to M. Frey, there are 100 pain points per 1 cm; There should be about 900 thousand pain points on the entire surface of the skin.

According to Frey's theory, pain sensitivity has its own independent not only peripheral, but also central nervous system. A. Goldscheider and A. Pieron deny this. Goldscheider recognizes the unity of receptors and peripheral nerve pathways for pain and tactile sensitivity, believing that the nature of the sensation depends on the nature of the irritation. Pain sensitivity is characterized by low excitability. Impulses arising after painful stimulation are characterized by slow conduction. Adaptation to pain impulses occurs very slowly.

Psychologically, pain is most characterized by the affective nature of sensations. It’s not for nothing that they talk about sensation and the feeling of pain. The sensation of pain is associated with a feeling of displeasure or suffering. In general, in psychological terms, some interpret pain as a specific sensation, while others consider it as a particularly acute manifestation of the affective quality of the unpleasant. Pain is undoubtedly an affective reaction, but is associated with intense irritation of only certain sensory apparatus. There is reason to talk about the specific sensation of pain without dissolving it in the affective-sensual tone of the unpleasant; pain is a clear manifestation of the unity of sensory and affective sensitivity. The painful sensation may consist in unity with the affective and cognitive moment. If with a burn only the affective moment of acute pain sensitivity is manifested, then with an injection, when the painful nature of the sensation is associated with tactile moments, in the painful sensation, in unity with the affective reaction, the moment of sensory cognition appears - differentiation and localization of painful irritation.

Proprioceptive sensations

Feelings of balance

Receptors for the sense of balance are located in the inner ear, which consists of three parts: the vestibule, semicircular canals and cochlea. Balance receptors are located in the vestibule.

The movement of fluid irritates the nerve endings located on the inner walls of the semicircular tubes of the inner ear, which is the source of the sense of balance. We get a sense of balance not only from the named receptors. For example, when our eyes are open, the position of the body in space is determined with the help of visual information, as well as motor and skin sensations, through the information they transmit about movement or information about vibration. In some special conditions, for example, when diving into water, we can obtain information about the position of the body only through a sense of balance. Signals coming from balance receptors do not always reach our consciousness. In most cases, our body reacts to changes in body position at the level of unconscious regulation.

Sensations of movement

Receptors for kinesthetic (motor) sensations are located in muscles, tendons and joint surfaces. These sensations give us an idea of the magnitude and speed of our movement, the position in which this or that part of the body is located. Motor sensations play an important role in coordinating our movements. When performing a particular movement, our brain receives signals from receptors located in the muscles and on the surface of the joints. If a person has impaired processes of forming sensations of movement, then by closing his eyes, he can walk, since he cannot maintain balance in movement. This condition is called ataxia, or movement disorder.

In psychology there are different approaches to classification of sensations . The traditional approach involves identifying types of sensations depending on the specifics of the sense organs: they distinguish visual, auditory, gustatory, tactile and olfactory Feel. However, this classification is not exhaustive. Currently, the classification of sensations is based on two basic principles: systematic And genetic .

Systematic classification was proposed by an English physiologist C. Sherrington (1857-1952) . Taking as a basis the nature of the reflection and the location of the receptors, he divided all sensations into three groups: exteroceptive, proprioceptive and interoceptive.

The largest group consists of e xteroceptive sensations , reflecting the properties of objects and phenomena of the surrounding world and arising when a stimulus acts on receptors located on the surface of the body. Among the sensations in this group are contact And distant. For contact sensations to occur, direct action of the object on the receptor is necessary. So, in order to evaluate the taste of food, we need to taste it; to feel the character of the surface of an object, we need to touch it.

For distant sensations, direct contact with the object is not necessary, since the receptors respond to stimulation coming from objects distant at some distance. Examples of this type of sensation are visual and auditory sensations.

Olfactory sensations , according to a number of psychologists, occupy a kind of intermediate position in the structure of exteroceptive sensations. On the one hand, they arise at a distance from the object, on the other, the molecules that determine the smell come into direct contact with the olfactory receptors. Consequently, olfactory sensations can be characterized as both distant and contact.

Proprioceptive(Latin proprius – own) Feel - these are sensations that reflect the movement and position of the body thanks to receptors located in the muscles, ligaments and vestibular apparatus. The role of proprioception as the basis of movements in animals was studied by Soviet psychologists A.A. Orbeli And PC. Anokhin, in humans - ON THE. Berstein. Proprioceptive sensations, in turn, are divided into kinesthetic (motor) and static, or balance sensations. The receptors of the last subgroup are located in the semicircular canals of the inner ear.

Interoceptive(organic) Feel - these are sensations that arise when an irritant acts on receptors in internal organs and tissues and reflect the internal states of the body. Interoceptive sensations represent the most ancient and elementary group. Interoreceptors inform a person about various conditions internal environment body (for example, the presence of biologically useful and harmful substances in it, body temperature, pressure, chemical composition of liquids).

Exteroceptive sensations are the most studied, interoceptive sensations are the least studied. In foreign psychology, the latter are sometimes called "sphere of dark (secret) feelings". They play an important role in making diagnoses in medicine, as well as in dream analysis in psychology. Today, almost any large treatment and preventive medical center has special equipment that can monitor the reaction of internal organs to an irritant. Using this procedure medical centers can diagnose various diseases of internal organs even in the early stages.

However, not all sensations can be classified into one of the three identified groups. In this case, we talk about intermodal (intermediate) sensations. These include, for example, vibration sensations , occupying an intermediate position between tactile and auditory. Special meaning they acquire when the organs of vision or hearing are damaged.

The deaf-blind mute O. Skorokhodova writes that if she tries to imagine people’s lives, movement in the city, then noise and sounds appear to her in the form of continuous vibrations. There was such a case: she felt how the moving air touched the surface of her face, and woke up from the movement of the air.

As already noted, another approach to the classification of sensations is possible - according to their corresponding sense organs (i.e. modalities). In this regard, we can cite the statement of the French philosopher D. Diderot:

“Our feelings are the keys that are struck by the nature around us.”

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 far from full 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 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?

A person’s emotions and inner feelings reflect his attitude towards 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 to 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. The impact of 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.

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Introduction

From an everyday point of view, it is difficult to imagine something more natural than seeing, hearing, feeling the touch of an object...

We are able to perceive the loss of one of them as something irreparable. The phenomena of sensations are so primitive that, perhaps, in everyday practice there is no specific definition for them. All living beings with a nervous system have the ability to sense sensations. As for conscious sensations, they exist only in living beings that have a brain and cerebral cortex.

By their origin, sensations from the very beginning were associated with the activity of the body, with the need to satisfy its biological needs. The vital role of sensations is to promptly and quickly convey to the central nervous system, as the main organ of activity control, information about the state of the external and internal environment, the presence of biologically significant factors in it.

Sensation is the simplest mental process, consisting of the reflection of individual properties of objects and phenomena of the material world, as well as the internal states of the body under the direct influence of stimuli on the corresponding receptors.

A receptor is an organ specially adapted for the reception of stimuli, a sensory system that can be considered a “Gateway of consciousness or an input device (in the language of cybernetics).”

In order for us to be aware of any factor or element of reality, it is necessary that the energy emanating from it (thermal, chemical, mechanical, electrical or electromagnetic) first of all be sufficient to become a stimulus, that is, to excite any of our receptors . Only then will electrical impulses arise in the nerve endings of one of our sense organs, and the process of sensation can begin. The initial analysis of the stimulus and encoding of the signal is carried out by receptor cells, and then the encoded signal is transmitted along sensory nerves to centers in the spinal cord and brain.

According to modern data, the human brain is a highly complex, self-learning analog computing machine, working according to genotypically determined and lifetime acquired programs that are continuously improved under the influence of incoming information. By processing this information, the human brain makes decisions, gives commands and controls their implementation.

Based on the nature of the reflection and the location of the receptors, it is customary to divide sensations into three groups:

Exteroceptive;

Interoceptive;

Proprioceptive.

In this work, we will focus on the study of exteroceptive sensations, give them definitions, and take a more specific look at all types and their properties.

1. exteroceptive sensations and their types

Exteroceptive sensations are sensations that arise when external stimuli act on receptors located on the surface of the body. These include visual, auditory, skin, taste, and olfactory sensations.

There are two types of sensations:

Contact sensations, that is, when irritation of receptors occurs through direct contact with objects affecting them. These include tactile and gustatory sensations.

Distant sensations, that is, when receptors respond to stimuli emanating from a distant object. These include: visual, auditory, olfactory sensations.

1 .1 Skin sensations and touch

When we touch objects different forms and surfaces, the brain receives more accurate signals than those coming to it from the organs of vision, hearing, smell and taste.

The most difficult thing to determine and understand is the mechanisms of touch: after all, in fact, it is a whole complex of different sensations. In addition, the sense of touch seems to insure other senses and certify that what we are seeing is actually what they told us about.

Unlike the other four senses, which are realized through specific organs - eyes, ears, nose or mouth - tactile sensations are perceived throughout the body, that is, tactile receptors are located in the human skin.

Skin sensations include tactile, temperature and pain sensations.

Let's look at each irritant in more detail.

Pain is a biologically very important protective device for the body, in our case for humans. Occurring under the influence of irritations that are destructive in nature and strength, pain signals danger to the body.

There are areas that are insensitive to pain and others that are much more sensitive. On average, there are 100 pain points per 1 cm2.

The feeling of pain for a person is usually associated with a feeling of displeasure and suffering, of course, if the person does not have mental disorders.

Temperature sensations:

Temperature (thermal) sensitivity gives us the sensations of heat and cold. This sensitivity has great importance for reflex regulation of body temperature. Temperature sensations provide relative independence in relation to temperature changes in the environment (winter, summer, intermediate seasons). At the same time, depending on the intensity of the stimulus and the structural relationship of the stimulus to the perceiving apparatus, not only the number of sensitive points changes, but also the quality of the receiving sensation: the sensation of warmth is replaced by a sensation of pain, the sensation of pain turns into a sensation of warmth, etc.

Thermal sensitivity is associated with thermoregulation. Based on temperature sensations that first appeared in birds and mammals and persist in humans, automatic regulation of internal body temperature, relatively independent of the environment, is complemented by the ability to create an artificial environment - heated and cooled dwellings, winter, and devices accompanying the creation of this environment - summer or demi-season clothing, household appliances (air conditioners, heaters, shades, etc.), etc., with the help of which a person maintains the most favorable environment for his body.

Temperature conditions are reflected in thermal sensitivity and affect a person’s overall activity and performance. So, for example, if a person is hot, then a decrease in activity and performance follows, and drowsiness and general fatigue may even occur.

Touch, pressure (tactile sensations):

The sensations of touch and pressure are closely related. The pressure feels like a strong touch. A characteristic feature of the sensations of touch and pressure (unlike, for example, pain) is their relatively precise localization, which is developed in a person as a result of experience with the participation of vision and muscle sense. Pressure receptors are characterized by rapid adaptation. Because of this, we usually feel not so much pressure as such, but changes in pressure.

In touch, the sensations of pain, heat and cold, touch and pressure interact. The interaction of the sensations of pressure and temperature gives us the sensation of wetness. The combination of moisture and a certain pliability, permeability allows us to recognize liquid bodies as opposed to solid ones. The interaction of deep pressure sensations is characteristic of the soft sensation: in interaction with the thermal sensation of cold, they generate sensations of stickiness. The interaction of various types of skin sensitivity, mainly again of a moving hand, also reflects a number of other properties of material bodies, such as: viscosity, oiliness, smoothness, roughness, etc.

Skin sensations are closely related to motor sensations, uniting functionally in a special organ of human labor and cognition - the hand. The combination of skin and motor sensations constitutes the sense of touch of an object. Touch is a person’s feeling of the objects around him, and is associated with the impact on them. With touch, cognition of the material world occurs in the process of movement, which turns into a consciously purposeful action of feeling, effective cognition of an object.

During individual development, from early childhood, the hand is one of the most important organs of cognition of the surrounding world. The baby reaches out with his little hands to all objects that attract his attention. Preschoolers and often junior schoolchildren Also, when they first become acquainted with an object, they grab it with their hands, actively rotate it, move it, and lift it. Thus, sensation plays the role of effective familiarization in the process of active cognition of an object in an experimental situation.

Typically, the sense of touch functions in humans in connection with vision and under its control. In cases where, as is the case with the blind, the sense of touch acts independently of vision, its distinctive features, its weak and strengths. That is, with the help of touch we can distinguish the shape of an object, its size, material form (hardness, liquid, viscosity, etc.), but without vision we will not be able to determine all the colorfulness of this object, feel the color saturation, brightness, lightness, etc. d.

But, nevertheless, the entire process of teaching the blind, and to an even greater extent the deaf-blind, is based on touch, on the activity of the moving hand, since teaching them to read and, therefore, mastering one of the main means of mental and general cultural development is accomplished by them through palpation - by perceiving convex letters with the fingers. Palpation is also used in the perception of speech by deaf-blind people. “Listening” to speech by deaf-blind people using the “voice reading” method involves the deaf-blind person putting his hand with the back of his hand to the speaker’s neck in the area of the vocal apparatus and, through tactile-vibrational perception, catching speech.

The life and work of many blind people who have reached a high level of intellectual development and work as teachers, sculptors, writers, etc., serves as a fairly clear indicator of the capabilities of the tactile-motor learning system.

1 .2 Olfactory and gustatoryFeel

The senses of smell and taste are closely related; they are types of chemical sensitivity. This means that they are a reaction to chemicals present in the environment. When we taste something, we feel the presence of certain chemical substances in our mouth, and when we smell it, we register their presence in the air in gaseous form.

Smell and taste, once as necessary for human survival as hearing, touch and vision, are now much less developed than in animals and play a secondary role.

From the moment man rose from all fours and lifted his nose from the ground, his life ceased to depend to the same extent on the sense of smell and taste as the life of other animals. Having lost their former significance, these physical senses now serve a person almost exclusively to select and enjoy food and drink.

Smell:

It is known that a small area at the back of the nasal cavity is replete with nerve endings that sense odors. This area, called the olfactory epithelium, or olfactory area, is literally packed with millions of nerve endings. Each of them has at least a dozen tiny hairs, or flagella. They are constantly moistened with mucus, which also serves as a trap for odorous substances. But due to the inaccessibility of the olfactory region, it is difficult for scientists to study the processes occurring in it.

It is believed that when odorous substances accessible to our sense of smell are inhaled with the air, they dissolve in the mucus that moisturizes the flagella, as a result of which these finest hairs are covered with a solution of odorous substances. Reacting to them, the flagella send signals to the olfactory cells for further transmission along the corresponding nerve fibers (they are called olfactory nerves). These signals are then transmitted to the olfactory medulla, a region of the brain. All olfactory cells that act as receptors for chemicals recognized by smell are exactly the same, so it remains a mystery how they distinguish thousands of diverse odors.

Over the centuries, people have identified six main odors: floral, fruity, fetid, spicy, resinous (like turpentine) and burning.

To have an odor, a substance must evaporate microscopic particles. The smallest building blocks of any substance are molecules, and olfactory cells are thought to be able to distinguish molecules by their shape. The more particles a substance emits, the stronger the smell. For example, chicken soup simmering on the stove smells stronger than cold chicken on a plate because the steam releases more odorous particles into the air. They are recognized as odors due to their ability to dissolve in water. Heat releases more particles into the air, and the moisture in the air increases their concentration, so odors become stronger in a warm, humid atmosphere. You probably yourself have noticed that in the warm haze after summer rain, the fragrance of the garden or grass intensifies; or what a pinch of bath salt makes hot water stronger aroma than the whole dry package.

If you enter a room where someone is eating cutlets with onions, the pungent smell will immediately hit your nose, although the people present there will not notice it. This phenomenon is called adaptation. The reason seems to be that when all the receptors are "filled" with odorous chemical particles, they stop sending signals to the brain.

In human life, the sense of smell plays a large role as a connector with a person’s emotional sensual tone: almost any olfactory sensation has a more or less pronounced character of pleasant or unpleasant; many cause very strong positive or negative reactions. There are smells that are unbearable and others that are intoxicating. Some people are particularly sensitive to their effects, and the sensitivity of many in this regard is great, which has given rise to an entire industry - perfumery.

Much more is known about taste than about smell, and it is generally accepted that there are only four basic tastes: sweet, salty, sour and bitter. But we owe all the richness of shades of what is called taste to the sense of smell. With a severe cold, the sense of smell temporarily disappears and food becomes tasteless. But the fact is that when we have a cold, we receive information about taste only from the tongue. As experiments have shown, when tasting foods only with the tongue, a person cannot distinguish even a peeled apple from a raw potato.

Like odorous chemical compounds, the substances that give us the sensation of taste must be dissolved. Only when dry food is dissolved by saliva can we determine its taste. The presence of salt is determined very quickly, as it quickly dissolves in saliva. Substances that are more complex in composition take longer to dissolve in the mouth, and therefore we do not perceive their taste as quickly as salt.

The receptors that pick up signals from the dissolved chemicals that make up our food are called taste buds. These are clusters of microscopic cells, or nerve endings, on tiny tubercles located on the tongue, palate and larynx. Each taste bud is a cluster of more than 50 cells connected to the brain nerve fibers. All taste buds are capable of distinguishing four basic tastes. Some of them serve as supporting cells, while the rest serve as taste cells. Like smell receptors, each taste cell has a tiny hair (microvilla). The outer ends of the taste buds are connected to the tactile nerves, making the taste and feel of food in the mouth closely related. When you hear the debate about whether thinly sliced beef or coarsely sliced beef tastes better, you may wonder what the difference actually is. However, the taste perception of food also depends on the touch of food with the tongue. The top (tip) of the tongue reacts best to sweet, its lateral edges to sour, the area adjacent to the top to salty, and the root region to bitter. Like smell receptors, all taste buds are similar to each other, but they are grouped differently in different parts of the tongue. When the taste buds come into contact with dissolved chemicals, they emit an electrical impulse that travels through the nerves to the brain.

In addition to taste, our idea of what we eat is influenced by a whole bunch of impressions. First of all, gases released when chewing food rise into the nasal cavity, affecting the sense of smell. The structure of food also matters. Temperature and pain sensations are involved in the process - after all, spicy food stimulates pain receptors (smearing adjika on your face, you will feel the same burning sensation on your skin as on your tongue). Touch and pressure receptors tell us whether we have crunchy pieces or cream, hard or soft food in our mouth; The ears perceive the sounds made by food when chewed. And, of course, memory - we will remember the disgusting dish for a long time.

1 .3 Auditory sensations

As objects move and collide, they vibrate and create vibrations that are transmitted through the air. The vibrations are perceived by the ear and converted into sounds of varying intensities.

We hear because our ears respond to sound waves or to small changes in air pressure. They convert these waves into electronic impulses and transmit them to the brain, where they are transformed into sounds.

Rice. 1 Structure of the ear: 1 -- external auditory canal; 2 -- eardrum; 3 -- Eustachian tube; 4 -- hammer; 5 -- anvil; 6 -- stirrup; 7 -- semicircular Canals; 8--10 -- snail; 11--12 -- Eustachian tube; 13 -- temporal bones of the skull

The human ear includes three compartments - the outer, middle and inner ear. The outer ear consists of skin fold with cartilage and the auditory canal leading to its hidden part. The visible part of the ear is called the pinna. It acts as a receiving device sound waves, which then enter the middle ear through the auditory canal and cause the eardrum at the entrance to the middle ear to vibrate. The middle ear is eight times smaller in size than the outer ear and is a small cavity inside the skull. This is where the eardrum is located, and the opposite part of the middle ear is connected to the nose by a narrow tube called the Eustachian tube. This allows the air pressure in the middle ear to be equalized with respect to external environment. If the pressure changes, our ears must adjust to this, which sometimes causes "popping" in the ears. In the cavity of the middle ear there are three bones, each of which has a characteristic shape: the hammer, the incus and the stapes. Air vibrations reflected by the eardrum pass from the malleus to the stapes and then through the oval window of the vestibule, which connects the middle and inner ear. In the inner ear there is a labyrinth - three fluid-filled tubes, thanks to which we feel balanced pressure. There is also a miniature spiral tube (cochlea), consisting of two channels and a duct. These channels and ducts are filled with fluid. The duct also contains tiny sensory hair cells covered with a narrow membrane film. These cells and membrane make up the organ of Corti. It is he who is the real auditory center. The vibrations passing through the cochlea cause the membrane to move back and forth. As the membrane moves, it pulls on the hair cells, and they send electrical signals through the auditory nerve to the brain. The brain deciphers the signals and perceives them as sounds.

Auditory sensations vary in pitch, strength and timbre.

The pitch of a sound is mainly determined by the number of vibrations per second. The higher the vibration frequency, the higher the sound, and vice versa. However, the pitch of the sound is also influenced by the intensity of the sound. So, if you amplify a high sound, it seems even higher. If you amplify a low sound, it seems even lower.

The human hearing organ reacts with an auditory sensation to sounds ranging from 16 to 20,000 vibrations per second. The ear is most sensitive to sounds in the region of about 1000 vibrations per second. Sounds lying below the extreme limit of the sensation of low sounds are called infrasounds. Sounds lying above the extreme limit of high sounds are called ultrasounds. Animals can also perceive sounds that the human ear cannot perceive: for example, insects perceive ultrasound up to 80,000 vibrations per second.

The strength of the auditory sensation is called loudness. Loudness is mainly related to the intensity of the sound, but it also depends on the pitch. This is explained by the fact that the human ear is differently sensitive to sounds of different pitches. Therefore, sounds that are equal in intensity but different in pitch have different volumes.

The timbre of a sound is its specific quality, which distinguishes from each other sounds that are equal in fundamental frequency and intensity, but different in the composition of additional vibrations. People's voices and the sounds of individual instruments are characterized by different timbres. Timbre depends on those additional pure sounds included in a given sound, which are usually an integer number of times greater than its main sound. These sounds are called harmonic partials (harmonics).

Auditory sensations are characterized by spatial localization: the sound stimuli affecting us are localized in one direction or another. Localization of sounds is achieved through the paired work of the cerebral hemispheres. The signal for the direction of sound is the difference in the time of arrival of sound in each ear (and, consequently, the arrival of excitation in each hemisphere), caused by the different distance of each ear from the sound source (binaural effect). By artificially creating a delay in the arrival of sound in one ear relative to the other, you can create the illusion of a change in the direction of the sound.

For most people, hearing acuity decreases with age. This is explained by the fact that the ear bones lose their original mobility, and therefore vibrations are not transmitted to the inner ear. In addition, ear infections can damage the eardrum and negatively affect the functioning of the ossicles. If you experience any hearing problems, you should immediately consult a doctor. Some types of deafness are caused by damage to the inner ear or auditory nerve. Hearing loss can also be caused by constant noise exposure (for example, in a factory floor) or sudden and very loud sound bursts. You should be very careful when using personal stereo players, as excessive volume can also cause deafness.

1 .4 Visual sensations

We receive most (up to 80%) of information about the world around us through our eyes.

Our eyes are specifically designed to provide us with information about depth, distance, magnitude, movement and color. In addition, they are able to move up, down and in both directions, giving us the widest possible view.

The eye is connected to the brain via the optic nerve. This nerve is located inside a special process attached to the back wall of the eye. It transmits signals entering the retina in the form of impulses, which are deciphered in the brain.

Each eye sees objects from a slightly different angle, sending a signal to the brain. Our brain, even in very early childhood, “learns” to bring both images together so that we do not see double contours. Images superimposed on each other allow you to see the volume of objects, and whether one object is in front or behind another. This phenomenon is known as three-dimensionality of the image, or "3-D". In addition, the brain allows us to correctly distinguish between up and down. When light is refracted as it passes through the lens, it leaves an inverted image on the retina. Our brain “reads” it and immediately turns it “from head to foot.” However, the newborn initially sees all objects upside down.

Rice. 2 Schematic section of the eye

First, let's describe the structure of the eye. The human eye is spherical in shape. In the center of its anterior section there is a slightly convex transparent layer, or cornea. It is connected to the white, or sclera, which covers almost the entire outer surface of the eye. The sclera is covered with thin membranes penetrated by tiny blood vessels.

The cornea is the first lens through which the light ray passes. She has a fixed focus and never changes position or shape. Beneath the cornea is the iris, or “iris.” In Greek this word means "rainbow". Most often, irises are blue, green or brown. Essentially, the iris is a muscular disc with a hole in the center. This hole is the pupil, through which light enters the eye. The iris controls the amount of light entering the eye through the pupil. In very bright light, it narrows and the pupil shrinks to the size of a tiny dot, letting only a small amount of light into the eye. In dim lighting, it relaxes and the pupil dilates, allowing light to enter. The pupils may also dilate in cases where you are overwhelmed by some strong feeling, for example, love or fear.

Behind the iris is a second lens, or lens. It is much more mobile and flexible than the cornea. It is held in place by a whole network of fibers called suspensory ligaments. The lens is surrounded on all sides by ciliary muscles, which give it various shapes. Let's say, when you look at some distant object, these muscles relax, the lens increases in diameter and becomes flatter. When looking at a closer object, the curvature of the lens increases. Behind the lens is the inner chamber of the eye, filled with a gelatinous substance called the vitreous. Light must first pass through this substance and only then hits the retina - the layer covering the back and side walls of the inner chamber of the eye. The retina consists of 130 million light-sensitive cells called rods and cones. The rods are sensitive to light, but do not distinguish colors, with the exception of blue and green. Cones capture all colors and help us see more clearly, but they stop working when there is insufficient light. That is why, with the onset of twilight, our vision weakens, we see colors worse and see everything in blue or gray-green tones. The French call this time of day the “hour of blue.” In very bright light, the rods close, giving up all the work to the cones. As the light weakens, the sticks come to life, but this does not happen immediately: when you enter a dark room from a sunlit street, your eyes only gradually get used to the darkness, and when you go out into the sunlight, you seem to go blind for a moment. The cones are concentrated in a fovea on the back wall of the retina, and most of the rods are located around it. The fovea is located near where the optic nerve exits, where there is a small tear in the retina. Light rays do not reach this area, which means that there is a tiny “blind spot” in the back of each eye.

All visual sensations arising from the action of light can be divided into two groups: sensations of achromatic colors (all shades of gray, as well as black and white) and sensations of chromatic colors (all colors except black, white and all grays). Ordinary sunlight, which we perceive as white, consists of a number of chromatic rays. This is easily demonstrated by passing sunbeam through a prism that splits white light into a spectrum.

It is convenient to observe the mixing of colors into one common color by looking at a rapidly rotating circle made up of several sectors of different colors. The phenomenon of color mixing, which was indicated by Newton, obeys certain laws. These laws are as follows:

1st law. For each color there is a different light from mixing with which a white or gray (achromatic) color is obtained. Such colors that mutually neutralize each other are called complementary (bluish-green is complementary to red, blue is complementary to yellow, etc.).

2nd law. When two non-complementary colors are mixed, a new color is obtained that is intermediate between them (mixing blue and red produces purple, a mixture of red and yellow - orange).

3rd law. The color of the mixture does not depend on the spectral composition of the colors being mixed, i.e. each of the mixed colors can itself in turn be obtained by mixing other colors (mixing yellow with blue equally produces gray regardless of whether it is yellow spectrally pure or the result of mixing other colors).

The laws of color mixing are explained by the so-called three-component theory of vision, first expressed by Lomonosov and further developed by Jung, Helmholtz and Lazarev. The starting point for this theory was the conclusion following from the laws of color mixing, namely: all the diversity color sensations can be obtained by mixing three colors taken as primary (red, green, blue). According to the three-component theory, there are three color-perceiving apparatuses in the retina of the eye. Excitation of the first of them gives a sensation of red color, the second - green color, the third - blue color. Usually the color affects three or two devices at once. At the same time the light different lengths waves act on each of these devices with different efficiency. Depending on the ratio of excitation processes caused in these devices, sensations of different colors arise. The sensation of white color occurs when the excitation of all apparatuses occurs equally strongly.

When characterizing color, one should distinguish between its three main properties: lightness, hue and saturation.

The lightness of the color is determined by the brightness of the stimulus and the sensitivity of the eye to it; it characterizes the effect of a stimulus on the eye by intensity.

The color tone characterizes specific features of a given color and depends on the composition of the rays acting on the eye (on the wavelength of these rays). In cases where the eye is affected by the color of a surface, the color tone is determined by the predominant reflection of rays of a certain wavelength. Achromatic colors do not have a color tone, since in these cases the surface equally reflects all rays (of all wavelengths).

Color saturation is the difference between chromatic color and gray of equal lightness. Low-saturated colors are usually obtained by adding a significant amount of white or gray to the chromatic color.

In visual sensations there is also adaptation, or color adaptation, which is expressed in a decrease in the sensitivity of the eye to a certain color stimulus due to the duration of its action. Both the appearance of a sensation and its disappearance do not occur suddenly and with the end of the stimulus. Therefore, after the cessation of the stimulus, a “trace,” or consequence, of the irritation remains in the eye, which gives a “consistent image.” An example would be a simple experiment: for 1 minute you need to look, for example, at a white skull drawn on a white sheet of paper, then look at a white wall, where an image of a skull will clearly appear.

A little about visual impairments and ways to eliminate them.

The most common visual impairments include myopia and farsightedness. Myopic people have trouble seeing distant objects, while far-sighted people have difficulty seeing what is nearby. These vision defects are almost always caused by the shape of the eyeball. For perfect vision, the eyeball must also have perfect shape ball. However, in nearsighted people the anteroposterior diameter of the eyeballs is elongated, while in farsighted people it is shortened. Myopia and farsightedness can be easily corrected by wearing glasses or contact lenses. Scientists have recently discovered a new way to correct myopia by surgically flattening the cornea.

The shape of the eyeball can affect vision in another way, causing astigmatism. It usually occurs together with myopia or farsightedness. The curvature of the corneal walls should be the same everywhere, like a soccer ball. But some people have corneas that look more like an oval rugby ball, and their eyes can't focus light rays properly. We say that an eye is squinting when it is directed away from the other eye - often towards the nose or temple, and sometimes up or down. The reason for this is often “laziness” of one of the muscles that controls the movement of the eyeball. To “spur” the squinting eye to normal operation, the healthy eye is covered with a bandage. If this does not help, you have to wear glasses or have surgery.

Glaucoma is an eye disease in which the volume of aqueous fluid in the chamber between the iris and cornea increases, causing pain and increased intraocular pressure. Vision deteriorates, and if glaucoma is not treated, complete blindness can occur. Sometimes a laser is used to cut a tiny drainage hole in the iris to drain fluid, which helps relieve pressure inside.

Cataract is a clouding of the lens, in which the patient looks at the world as if through a freezing window. Cataracts develop slowly and are not painful. It is removed by destroying the lens with a special ultrasonic probe. The removed lens is replaced with a miniature plastic lens.

Conclusion

exteroceptive sensation stimulus receptor

Thus, sensations play an important role in human life. Sensations, reflecting the properties of objects in the objective world, help a person in the cognitive process, and are also a sensory reflection of a person’s reality.

With the help of sensations, a person performs activities, both consciously and unconsciously, but in both cases, this activity can be of an educational nature, and the already acquired knowledge and skills can also be improved.

It should be remembered that there are people deprived of any sensation (blind, deaf-mute, deprived of any parts of the body, etc.), while in these people other senses become more acute.

Summing up the results of this work, I want to say that in order to feel like a full-fledged person, you need to have the whole complex of sensations, take care of them, develop their sensitivity and improve them.

Bibliography:

1. Gamezo M.V., Domashenko I.V. Atlas of psychology. - M.: Pedagogical Society of Russia 2004.

2. Electronic textbook. Psychology and pedagogy: Tutorial for universities / Compiled by Radugin A.A. - M.: Center, 2002.

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