What are sense organs? Subtle human feelings

Interesting Facts about the senses. Part 1.

The human sensory system is both a defense system and a system for perceiving the world, and the ability to fully contact the world. A healthy person has 5 senses. Each has its own functions and purpose.

How are human senses structured and how do they function?

A healthy person has 5 senses. They are divided into two types: remote and contact. The contact organs include the organs of taste and touch: tongue and fingers. Remote ones include: ears, eyes and nose. It is also important to note that disturbances in one place lead to multiple changes in other parts of the body. If you know what's going on with what, you can easily diagnose and fix it. key reasons illness. And the symptoms will go away on their own.

This is interesting! When sensitivity is impaired in some organs, others increase their abilities to compensate for a more or less normal perception of the world and protect the body. For example, with complete or partial loss of vision, hearing acuity or sense of touch increases significantly.

Speaking about the senses, it is worth saying that the main thing here is the brain. All others are only intermediaries, because all signals are ultimately transmitted to the brain.

Eyes and their functions

The eyes are responsible for the perception of visual information. They are more closely connected to the brain than other organs. That is why through vision a person perceives greatest number information, and it is processed most quickly by the brain. Therefore, vision is considered the most important means of world perception.

The eyes help to perceive colors and light, objects, allow you to see the world in volume, have the ability to focus directly on the central object or on the side ones. The eyes provide a wide range of vision. This is also a way of protection. By ear, for example, you can’t always immediately determine exactly where a sound is coming from. And the eyes immediately determine it accurately.

This is interesting!

• Lateral, or peripheral, vision is much better in women than in men. This also explains the ability of men to focus on only one thing, while women can do several at once.
• The eyes have the ability to distinguish up to 500 shades of gray.
• The iris of the eye is as unique as a fingerprint.

Therefore, it is important to protect your eyesight. Natural peptide bioregulators and other NPCRiZ drugs help not only prevent vision deterioration, but also restore it to some extent.

To prevent vision:

• Mesotel Neo;
• Geroprotector Retisil;
• Peptide complex No. 17;
• Peptide bioregulators: Visoluten, Cerluten;
• Bioregulators of vascular and brain functions: Pinealon, Vezugen.

For complex treatment:

Perfect solution - complex application NPTsRIZ products to solve various problems with vision.

Continued in the next article.

Sense organs are specialized structures through which parts of the brain receive information from the internal or external environment. With their help, a person is able to perceive the world around him.

Sense organs - afferent (receptive) section of the analyzer system. The analyzer is the peripheral part of the reflex arc, which communicates between the central nervous system and the environment, receives irritation and transmits it through pathways to the cerebral cortex, where information is processed and sensation is formed.

5 human senses

How many primary senses does a person have?

In total, a person usually has 5 senses. Depending on their origin, they are divided into three types.

• The organs of hearing and vision come from the embryonic neural plate. These are neurosensory analyzers, they belong to first type.
• The organs of taste, balance and hearing develop from epithelial cells, which transmit impulses to neurocytes. These are sensory epithelial analyzers and belong to second type.
• Third type includes peripheral parts of the analyzer that sense pressure and touch.

Visual analyzer

Basic structures of the eye: the eyeball and assistive apparatus(eyelids, eyeball muscles, lacrimal glands).

The eyeball has an oval shape, is attached by ligaments, and can move with the help of muscles. Consists of three shells: outer, middle and inner. Outer shell (sclera)- This protein coat opaque structure surrounds the surface of the eye by 5/6. The sclera gradually passes into the cornea (it is transparent), which makes up 1/6 of the outer shell. The transition area is called the limb.

Middle shell consists of three parts: the choroid, the ciliary body and the iris. The iris has a colored color, in the center of it there is a pupil, thanks to its expansion and contraction, the flow of light to the retina is regulated. In bright light, the pupil narrows, and in low light, on the contrary, it expands to catch more light rays.

Inner shell- this is the retina. The retina is located at the bottom of the eyeball and provides light and color perception. The photosensory cells of the retina are rods (about 130 million) and cones (6-7 million). Rod cells provide twilight vision (black and white), cones serve for daytime vision and color discrimination. The eyeball contains a lens and chambers of the eye (anterior and posterior).

The value of the visual analyzer

With the help of the eyes, a person receives about 80% of information about the environment, distinguishes colors and shapes of objects, and is able to see even with minimal light. The accommodative apparatus makes it possible to maintain clarity of objects when looking into the distance or reading closely. Auxiliary structures protect the eye from damage and contamination.

Hearing analyzer

The organ of hearing includes the outer, middle and inner ear, which perceive sound stimuli, generate an impulse and transmit it to the temporal cortex. Hearing analyzer inseparable from the organ of balance, therefore the inner ear is sensitive to changes in gravity, vibration, rotation, and movement of the body.

Outer ear divided into the auricle, auditory canal and eardrum. The auricle is an elastic cartilage with a thin ball of skin that detects sound sources. The structure of the external auditory canal includes two parts: cartilaginous at the beginning and bone. Inside there are glands that produce sulfur (has a bactericidal effect). The eardrum perceives sound vibrations and transmits them to the structures of the middle ear.

Middle ear includes the tympanic cavity, inside which are located the hammer, stirrup, incus and Eustachian tube (connects the middle ear with the nasal part of the pharynx, regulates pressure).

Inner ear It is divided into a bony and membranous labyrinth, with perilymph flowing between them. The bony labyrinth has:

• vestibule;
• three semicircular canals (located in three planes, provide balance, control the movement of the body in space);
• cochlea (it contains hair cells that perceive sound vibrations and transmit impulses to the auditory nerve).

The value of the auditory analyzer

Helps to navigate in space, distinguishing noises, rustles, sounds at different distances. With its help, information is exchanged when communicating with other people. From birth a person is hearing oral speech, learns to speak on his own. If congenital hearing impairment occurs, the child will not be able to speak.

The receptor cells are located at the back of the upper nasal passages. By perceiving odors, they transmit information to olfactory nerve, which delivers it to the olfactory bulbs of the brain.

With the help of smell, a person determines the good quality of food, or senses a threat to life (carbon smoke, toxic substances), pleasant aromas lift your spirits, the smell of food stimulates the production of gastric juice, promoting digestion.

Organs of taste

On the surface of the tongue there are papillae - these are taste buds, on the apical part of which there are microvilli that perceive taste.

Sensitivity of receptor cells to food products different: the tip of the tongue is receptive to sweet, the root - to bitter, the central part - to salty. Through nerve fibers, the generated impulse is transmitted to the overlying cortical structures of the taste analyzer.

Organs of touch

A person can perceive the world around him through touch, with the help of receptors on the body, mucous membranes, and muscles. They are able to distinguish temperature (thermoreceptors), pressure levels (baroreceptors), and pain.

Nerve endings have high sensitivity in the mucous membranes and earlobe, and, for example, the sensitivity of receptors in the back area is low. The sense of touch makes it possible to avoid danger - to remove your hand from a hot or sharp object, determines the degree of pain threshold, and signals an increase in temperature.

A person lives and works in the world around him, in the society of other people. All phenomena of the material world are perceived by us and reflected in our consciousness through the senses. With the help of the eyes (the organ of vision), a person perceives light, colors, shape and location of objects in the surrounding world. Sounds and noises are perceived by the hearing organ, taste qualities are determined using the organ of taste, the organ of smell serves to perceive various odors. Through the organ of touch (skin), a person gets an idea of ​​the temperature, hardness and nature of the surface, and the shape of objects. These five senses perceive signals outside world, affecting humans. Signals from the environment around us evoke in our consciousness a clear idea of ​​the sources of these signals, their qualities, reflecting the existence of an objective material world outside of us.

Peripheral nerves contain fibers that carry signals to the brain in the form of nervous excitement from nerve endings located in muscles, joints and ligaments. Based on these signals, a person determines the position of his body in space.

From all internal organs, signals continuously come to the central nervous system, reflecting the state of each organ. IN normal conditions These signals are most often not perceived by our consciousness and are manifested only by “general well-being.”

The sense organs are designed in such a way that each of them is best suited for the perception of certain signals - light, sound, etc. The main part of the sense organs are the nerve endings that perceive signals from the outside world.

The eyes are located in sockets formed by the bones of the facial part of the skull. Each eye consists of eyelids, eye muscles, the eyeball and the optic nerve extending from it. In the outer corners of the eye sockets there are lacrimal glands that secrete tears. When the eyelids move, tears wash away dust particles from the eyeball and moisturize it. Excess tear fluid enters the nasal cavity through special canaliculi.

The eyeball consists of the vitreous body, the lens and three membranes (Fig. 1). The anterior part of the outer (protein) membrane, which transmits rays due to its transparency, is called the cornea. Behind the outer shell lies the choroid, which contains blood vessels that supply the eye. The front part of the choroid is called the iris, which determines the color of the eyes. In the center of the iris there is a round hole called the pupil.

The inner layer - the retina - is located on back wall eyeball. It contains special cells - rods and cones, containing a light-sensitive substance, as well as nerve cells. The processes extending from these cells give rise to the optic nerve. The latter goes from the posterior pole of the eyeball to the cranial cavity, where it enters the brain.

Behind the pupil is a transparent lens shaped like a lentil. The cavity of the eyeball, limited by the membranes and the lens, is filled with a transparent vitreous body.

Light rays penetrate the cornea, pupil, lens, vitreous body and enter the retina. Under their influence, the light-sensitive substance in cones and rods changes, causing the appearance of signals in nerve cells retina. Next, these signals from the nerve cells go to their processes, which make up optic nerve, and along it they enter the brain (the occipital lobe cortex), where a sensation of light arises, an idea of ​​the shape of objects in the surrounding world.

Rice. 1. Schematic section through the eye and its accessory organs.
1 - upper wall of the orbit; 2 - eye shells; 3 - space between the eye and Tenon’s capsule; 4 - Tenon's capsule; 5 - levator muscle upper eyelid; 6 - superior rectus muscle; 7 - central artery of the retina; 8 - optic nerve; 9 - inferior rectus muscle; 10 - lower wall of the orbit; 11 - vitreous body of the eye; 12 - periosteum; 13 - inferior oblique muscle in a transverse section; 14 - orbicularis oculi muscle, 15 - orbital septum; 16 - lower fornix of the conjunctiva; 17 - cartilage of the lower eyelid, 18 - iris; 19 - lens; 20 - cornea; 21 - cartilage upper eyelid; 22 - conjunctiva covering the posterior surface of the upper eyelid; 23 - conjunctiva covering the eyeball; 24 - circular muscle of the eye; 25 – orbital septum.

The pupil has the ability to contract and expand, depending on the brightness of the light falling on the eyes. This is achieved with the help of smooth muscles present in the iris. In bright light, the pupil narrows, allowing less light rays to enter the eyeball; in low light, it dilates. Regulation of pupil width occurs reflexively, automatically, which ensures rapid adaptation of the eyes to different lighting conditions.

The organ of hearing consists of three differently arranged parts: the outer, middle and inner ear. The outer and middle ears serve to conduct sound vibrations; in the inner ear lies the nervous apparatus that converts sound vibrations into nerve signals (Fig. 2 and 3).

The outer ear is composed of Auricle and the external auditory canal is a channel for conducting sound waves.

Rice. 2. Frontal section through the organ of hearing (schematically).
1 - auricle; 2 - external auditory canal, 3 - eardrum; 4 - middle ear cavity; 5 - auditory tube; 6 - snail; 7 - semicircular canals; 8 - anvil; 9 - hammer; 10 - stirrup; 11 - endolymphatic duct; 12 - utricle; 13 - bag; 14 - temporal bone.

End ear canal closed by the eardrum, behind which lies the middle ear cavity. The middle and inner ear are located in the thickness temporal bone. In the middle ear cavity there are auditory ossicles (hammer, incus and stapes), connecting the eardrum with inner ear. A narrow tube called eustachian tube, the middle ear connects to the pharynx, from where air enters, filling the middle ear cavity.

Rice. 3. Eardrum and auditory ossicles from the inside.
1 - head of the hammer; 2 - its upper ligament; 3 - cave of the tympanic cavity; 4 - anvil; 5 - a bunch of it; 6 - drum string; 7 - pyramidal elevation; 8 - stirrup; 9 - hammer handle; 10 - eardrum; 11- auditory tube; 12 - partition between the half-channels for the pipe and for the muscle; 13 - muscle that strains the tympanic membrane; 14 - anterior process of the malleus.

In the inner ear there is a canal in the form of a cochlea filled with fluid. The cochlea contains very sensitive hair cells that perceive the vibrational movements of the fluid. The auditory nerve (connected with hair cells) originates from the cochlea, which enters the cranial cavity from the temporal bone and enters the brain, heading to the temporal lobes.

Air sound wave vibrates the eardrum and the associated auditory ossicles. The latter transmit vibrations of the liquid filling

cochlea (through the membrane in the wall of the inner ear). The movement of fluid irritates sensitive hair cells, the signals from which auditory nerve reach the cerebral cortex (temporal lobes). The sensation of sound arises in the cerebral cortex, its quality and direction are determined.

In addition to the hearing aid, the inner ear also contains a balance apparatus (labyrinths), which regulates the position of the body in space.

Odors are perceived by nerve cells located in the mucous membrane of the upper part of the nasal cavity. Fibers from these cells penetrate the cranial cavity through special openings and connect to the olfactory nerve, which passes to the temporal lobes of the brain. Along these nerve pathways, signals indicating the quality of various odors reach internal departments temporal lobes (on each side).

Taste cells (taste buds) are located on the surface of the tongue. When taste substances enter the tongue, signals arise in the taste cells, which pass through the nerve processes (emanating from these cells) into the cranial cavity and enter the corresponding temporal lobes of the brain. This is where the sensations of taste and smell are formed.

The skin contains the organ of touch (skin sensitivity). In addition to its sensitive function, human skin performs several other functions. It is a protective cover that protects soft fabrics from external influences, organ. discharge ( sweat glands), a thermoregulatory organ. The skin is constructed from the integumentary and connective tissue. In its thickness there are numerous sensory bodies, to which the endings of sensory nerve fibers approach, which merge into nerve trunks and, together with the motor nerves going to the muscles, form the peripheral nerves of the limbs and torso. These nerves enter the spinal cord through the intervertebral foramina of the spinal column. As part of it white matter sensory fibers go further to the brain, where they approach special sensory centers in the brain stem and further to the cortex of the parietal lobes cerebral hemispheres.

Touching the skin, exposing it to heat or cold, and painful stimulation cause the appearance of signals (excitation) in the skin's sensory bodies. From them, signals travel through sensitive nerve fibers to the spinal cord and reach the cerebral cortex, where a sensation arises that reflects the nature of the effect on the skin. The entire nervous apparatus, starting from the peripheral sense organ and ending with the sensitive centers located in the cerebral cortex, was called by I. P. Pavlov an analyzer. Through each given analyzer, a person perceives one or another property of the surrounding world, analyzes it, and compares these properties.

There are motor, auditory, visual, olfactory and skin analyzers. With the help of these analyzers, the cerebral cortex receives great amount signals reflecting the functioning of the body and the state of the external environment.

Most of the signals generated in these analyzers are reflected in our consciousness. The cerebral cortex is also an analyzer for all internal organs, from which it constantly receives signals about their work. These signals are usually not realized by us, but with very severe irritation nerves of the diseased organ, they begin to be reflected in consciousness in the form of a variety of unpleasant sensations and pains.

The result of analyzing all these signals is the other side of the activity nervous system- a response that regulates the functioning of individual organs (both normally and in case of illness or injury), causing changes in a person’s mental activity. Emphasizing the role of analysis of external environmental phenomena by the cerebral cortex, I.P. Pavlov called the cortex a set of analyzers.

The thermoregulatory role of the skin is carried out with the help of large quantity available in it blood vessels. In hot weather and strong muscle work The skin vessels dilate, and more heat is emitted from the surface of the skin, thereby preventing overheating of the body. All regulation of the lumen of blood vessels is carried out through the nervous system ( reflexively). Reflex regulation of the lumen of skin vessels thus ensures the preservation constant temperature bodies.

Human sense organs: the main organs, what they are responsible for, how they are connected to the brain. Hygiene rules.

Thanks to the presence of sense organs, we can easily adapt to the world around us. What is given from birth and is present to us all our lives is of little value, and if suddenly, due to some accident, we lose one or more feelings, we lose a part of ourselves. Unfortunately, we are not always taught from childhood how important this is, but if you are reading this article, it means that you, like us, have decided to take care of the most important thing in the world - your body!

Let's think about how we feel for a second:

• Close your eyes and imagine how people who do not have such a natural gift live;
• Imagine not hearing the smell of food, the aroma of flowers and the delicious aromas of your beloved family members;
• Think about it, if you could no longer taste your favorite dish or drink;
• Imagine putting your hand in water and it starts to blister, but you don't understand why.

And this is just a small list of the limitations experienced by people whose senses work poorly or do not work at all.

What are human sense organs?

Human senses are the very organs through which a person interacts with the world around him. With the help of the senses, a person can realize what awaits him at one time or another when he comes into contact with the world around him, cognize it and enjoy life.

How many basic sense organs does a person have and how many total sense organs?

Currently, scientists have approved six human senses, but there is constant debate that a person has many more senses and this is only a condensed concept.

The list of human senses includes:

• Ears (thanks to the ears we hear sounds and vibrations);
• Eyes (thanks to the eyes we see);
• Tongue (thanks to this organ we feel the taste and temperature of everything we absorb);
• Nose (the nose helps us hear smells and aromas);
• The skin (they provide tactile sensations, touch, feeling of pain and temperature of the surrounding world);
• Vestibular apparatus (thanks to this sense organ, we are aware of our place in space, maintain balance and feel weight and position).

5 main senses - taste, vision, hearing, touch, smell: their main functions and significance

In this section I would like to pay attention to each of the senses separately and highlight their significance for human life.

Eyes . With the help of vision we receive on average about 90% of information. The pupils, with the help of which we see, are formed in the embryo and continue to develop until birth, directly connected with the brain.

Vision, or rather visual analysis, consists of several functions:

• Eyeballs;
• Optic nerves;
• Subcortical centers;
• Higher visual centers in the occipital areas.

Can you imagine how long a signal travels in an instant so that we can see and process information in real time without delay? How fast eyeballs Having recognized the signal, they transmit it to the brain, and the brain instantly analyzes and gives a reaction to what it sees.

In addition, eyeballs are an ideal and unique optical device. Thanks to this, we can see at different distances, and we are also able to see both the whole picture (for example, a room) and the smallest detail (for example, a scratch on furniture).

The principle of operation of the eyes is very simple and at the same time very complex: light passing through the cornea of ​​the eye is refracted and the refracted passes through the lens, where it is refracted again and tends to the vitreous body, where it converges in focus on the retina. It sounds complicated, but you need to know this in order to understand that visual acuity directly depends on the cornea and lens, or rather their ability to perfectly refract light.

But that's not all! The eyes, thanks to the muscles located in them, are able to move in different sides, which significantly increases the speed of vision and also relieves stress on the spine.

Organs of taste . This organ is responsible for taste buds, thanks to which a person can evaluate the food he eats. This protects a person from eating spoiled foods, allows him to enjoy new and familiar tastes, and also tells the brain the most acceptable tastes, and therefore, the brain subsequently signals what kind of food he wants to eat.

There is a misconception that the tongue is responsible for taste, but for some reason they forget to tell you that special nipples and bulbs are located not only on the tongue, but also on the palate, epiglottis, and also on the upper part of the esophagus.

Interesting fact: the tongue is divided into several zones that best determine a particular taste. But even if the zone is not responsible for a given taste, this does not mean that it will not feel it, just not so brightly. Example: the lateral arches of the tongue most clearly sense bitterness, but this does not mean that the rest of the tongue, palate and larynx will not taste pepper.

It is worth noting that the organs of taste are closely interconnected with the organs of charm. For colds and viral diseases taste habits can change significantly and what gave pleasure can cause persistent disgust. After recovery, the situation will stabilize and return to its previous state.

Ears . It is believed that the most difficult people to adapt to in the world are those who have difficulty seeing and hearing aid. Indeed, in our fast-paced world it is quite difficult to live without acute hearing, and therefore it is important to carefully take care of what nature has given us.

The ear consists of three interconnected parts: external, internal and middle. The outside is the familiar shell, which is as individual for everyone as fingerprints. It is responsible for sound localization and also clearly identifies the sound source.

In the external passage, which goes from the outer ear to the internal organ, there are sebaceous glands, which produce earwax. It is she who, constantly coming out, prevents clogging of the inner ear. This is followed by the eardrum, which responds to sound vibrations. Followed by tympanic cavity- the basis of the middle ear. In this cavity there is a stapes hammer and anvil connected into a single whole. After them is the cochlea and semicircular canals, which are responsible for balance.

So, auditory waves are caught by the outer ear, move to the eardrum, from there to the three auditory ossicles and then to the cochlea, from the cochlea there is irritation to the auditory nerve and the brain perceives what is heard.

Organs of touch . Most people don't even realize what an important role they play. this function body. How important it is for us to understand whether we come into contact with hot or cold, smooth, rough, soft or hard. It is tactile sensations that bring endorphins (hormones of joy) when in contact with a loved one. Touching a favorite thing, an animal, and even the outside world can tell us no less than sight! Please note that children who have not yet accumulated enough life experience they touch everything and it is through touch that they study the world and gain that very experience.

But it is worth noting that the skin (they are the organs of touch) exclusively “catch” signals and transmit them to the brain, and the brain, having already analyzed it, reports what our fingers felt.

Nose or olfactory organs . In the nasal passages, a small part is occupied by olfactory cells. The shape of the cells resembles many tiny hairs and when moving they capture the subtleties of all kinds of aromas and odors. As with the sense of touch, olfactory cells pick up scents and transmit the signal to the brain, which is already processing the information. Signals are transmitted in this way: olfactory cells capture the aroma and transmit them through olfactory threads and bulbs to the centers of the brain. The sense of smell may be temporarily dulled during viral respiratory diseases and restored within a few days after recovery. Otherwise, the help of doctors is necessary.

The tongue is what sense organ?

The tongue, along with the larynx, palate and other parts oral cavity relate to the taste organs. We discussed the taste organs in more detail in the section above.

What sense organs does a person lack?

Many people have a question: what sense organs do humans lack? For science fiction writers, this is simply fertile ground for creating superheroes or, on the contrary, villains. We have identified the most popular sense organs that humans do not have, but if they existed, a person’s life would be much more comfortable.

• The ability to detect ultrasound is a unique gift of bats;
• Clear vision in the dark - the capabilities of cats and more are amazing!
• Electroreceptors with which stingrays and sharks are gifted;
• The lateral line of fish is ideal sensitivity in space, which contributes to both survival and hunting;
• Thermal locators that snakes are gifted with.

This is just a small list of the capabilities of the surrounding world that nature has not endowed us with or that we have lost in the process of evolution.

Sense organs and brain, nervous system: how are they interconnected?

Each sense organ is directly connected by nerve endings to the brain and continuously sends signals. The brain, in turn, analyzes the signals and produces ready-made information. It is worth noting that the brain rarely receives a signal from just one sense organ, and most often in a complex manner. So, for example, a child enters the kitchen and sees food (vision), hears the mother’s voice “Sit down to eat”, feels the aroma of food, sits down at the table and comes into contact with cutlery (a signal that food is about to arrive), and by the time the mother When a child puts a plate on the table, he most likely knows what the dish will taste like.

How do the senses help a person navigate the world?

Have you seen a newborn kitten, how it pokes in different directions, not yet understanding how to navigate in space. Likewise, a person without sense organs would move in space without understanding where he is and how to get to the right place, what needs to be done to avoid getting into trouble.

For example, a sense of balance helps a person understand where the earth is and where the sky is, even in a room without a single window. Also, thanks to this feeling, a person clearly navigates in space, moving in the desired direction without injury.

The hearing organs help to hear not only conversations with family, but also the sound of moving vehicles, running animals, etc. Having analyzed this sound, a person can correctly orient himself even if he does not yet see this object.

Vision in modern life one of the key sense organs, because our society is created in such a way that we receive 99% of information visually. According to statistics, people with visual impairments are the most severely limited in the modern world.

Thanks to the sense of touch and charm, a person not only experiences the most vivid and pleasant emotions, but can also protect himself from the dangers of our world. For example, repulsive odors signal to us that food is no longer suitable for consumption until it reaches the tongue. The smell of smoke and burning often saves people from fires and allows them to quickly extinguish or leave the room at the stage of fire.

Hygiene rules for the main sense organs

In order for the senses to serve us faithfully long years we must respond to them with care and regular care. Below we provide basic hygiene rules for the organs responsible for the senses.

• Organ of touch: all of our skin needs daily cleaning (shower or bath), moisturizing and nourishing as necessary. Particular attention should be paid to the palms and feet, since it is on their integument that maximum amount transmitting receptors vital information brain;
• Olfactory organ: as necessary, it is necessary to rinse and clean the nasal cavities from pollution and substances secreted by the body. In case of illness, treat according to the doctor’s recommendations;
• Organs of taste: the oral cavity needs daily brushing of the teeth, brushing with dental floss if necessary, as well as rinsing the mouth in the morning and evening, as well as after each meal;
• Hearing organs: if there are no problems in the ears, then cleaning the outer ear should be done after washing with cotton swabs or special swabs. In other cases, as necessary, it is necessary to clean out the wax, but only at the entrance to the ear, deeper, just like ear plugs should be cleaned exclusively by an ENT doctor;
• Eyes: along with skin eyes should be washed morning and evening, if worn contact lenses— clean them according to the instructions. If tearing, burning or other unpleasant sensations occur in the eyes, it is recommended to immediately consult a doctor.

Video: What controls our senses: human anatomy?

Sense organs are specialized peripheral formations that provide the perception of external stimuli acting on the body. Due to their high specialized excitability, certain sense organs provide the perception of only certain types of irritation. In this regard, a person has organs: vision, smell, taste, touch. The concept of “sensory organ” and “”, which is affected by the stimulus, should not be confused. So, for example, one should not confuse the eye as an organ of vision and the retina - a receptor that is part of the sensory organs, but constitutes only one of its components. In addition to the retina, the organ of vision (eye) includes the refractive media of the eye, its various membranes, and its muscular apparatus. Thus, the concept of sensory organs refers to a very specific peripheral formation. At the same time, it should be emphasized that the concept of sense organs is largely conditional, since the sense organ itself cannot provide sensation as such. For the emergence of one or another subjective sensation, it is necessary that the excitation that arises in the receptors comes from them to the central nervous system - to special sections of the cerebral cortex. It is with the activity of the higher parts of the brain that the emergence of subjective feelings. Thus, any of the sense organs represents only a peripheral section of a complex connection of nervous structures that ensure the emergence of a specific form of sensation (see Analyzers).

Sense organs are specialized receptor formations that ensure the body’s perception of changes occurring in the surrounding world and in the body itself. The biological purpose of the sense organs is their participation in the complex adaptive activity of the body, aimed at constantly balancing it with the environment (). Along with this, the senses, being an apparatus for perceiving the external world, take part in the creation of the subjective world of the organism, which is a reflection of external, objective reality.

With evolutionary development, this side of their function becomes increasingly important, opening up for the organism a wide opportunity to understand the outside world.

The sense organs are analyzers (q.v.) of chemical, mechanical, light, sound, temperature and other stimuli falling on receptors (q.v.), characterized by fine specialization. So, part of the visual receptors - rods - serves for twilight vision, and the other part of them - cones - for daytime vision; mechanoreceptors are divided into phase ones, which perceive dynamic, and static, which perceive static deformation, etc.

A distinctive feature of the sense organs is their high sensitivity (see) and the ability to function in a wide range of intensities of adequate stimuli.

The basic patterns of activity of the sense organs were established by measuring human sensations using the so-called psychophysical method. One of these patterns, described back in the 19th century, was called the Weber-Fechner law, according to which the magnitude of sensation (S) is proportional to the logarithm of the intensity of the current stimulation (J): S = algJ.

This law, confirmed later and objective methods research is common to various organs feelings and is observed mainly in the range of average intensity of stimulation.

Not all reactions of the senses reach consciousness in the form of sensations. Reactions occurring in internal organs, muscles, vestibular apparatus etc., remain in the form of a “dark feeling” (I.M. Sechenov). To study such reactions widespread received an electrophysiological method, which made it possible to study bioelectric phenomena (see) in receptors, single fibers and individual nerve cells. The implantation of microelectrodes made it possible to study the reactions of nerve centers and cells on the whole animal in combination with emotional and behavioral acts. Advances in cybernetics and bionics have opened up the possibility of modeling the functions of receptors and neurons and creating prosthetics that compensate, to one degree or another, for the lack of certain sensory organs. A major role in the objective study of the sense organs of humans and animals, especially in comparative physiological terms, is still played by the method of conditioned reflexes (see).

In response to the action of an adequate stimulus, the receptor of a particular sensory organ enters a state of excitation, which is based on a slow negative change in the charge (depolarization) of the receptor membrane, called the receptor, or generator, potential. The magnitude of this potential obeys the Weber-Fechner law. The receptor potential determines the occurrence of impulses in the nerve fiber extending from the receptor, the frequency of which is linearly related to the amplitude of the potential. An increase in the intensity of stimulation leads to an increase in the frequency of impulses in a separate nerve fiber and involvement in activity more fibers The resulting sensation is determined not by a simple frequency code, but by a complex of impulses in many nerve fibers that transmit information.

From point of view modern science the specificity of sensations depends on the organization of cortical projections (see Architectonics of the cerebral cortex). Thus, electrical stimulation of the cerebral cortex, carried out during neurosurgical interventions, causes a sensation in the person being operated on, the quality of which depends on the location of the stimulation. The application of electrodes to the visual projection causes a sensation of light, to the gustatory projection - taste, etc. The specific sensitivity of the sensory organs to certain stimuli depends on the structure of the receptors. The mechanism for transmitting information from receptors to the brain is common to all sense organs and is expressed in a flow of impulses characterized by different frequencies, durations and interpulse intervals.

Primary processing of incoming information is carried out at the periphery. This occurs because the receptors of each sense organ are anatomically interconnected, forming a receptive field innervated by a separate nerve fiber. Already in a single receptor, a complex interaction of excitation and inhibition can occur, carried out with the participation of an interneuron connected through collaterals with a nerve fiber extending from the receptor. The discharge of impulses in any fiber, in addition, depends not only on the stimulation parameters of a given receptor unit, but also on the spatiotemporal distribution of excitation throughout the entire group of interacting receptors. As a result of peripheral interaction, spatial and temporal contrasts of the stimulus are emphasized. The spatial summation of excitation determines the value of the area of ​​stimulation to characterize the magnitude and threshold of the reaction of the sensory organs. For visual apparatus this dependence is expressed by the formula: J·S=K, in which J is the intensity threshold, S is the area, K is a constant value. If we take into account that not all receptor elements can function in a given area, then the formula takes the form: J·S(P-p) = K, where P-p is the number of functioning elements (P. G. Snyakin).

In the sense organs, sensory units are distinguished that respond differently to the action of the stimulus: some respond to the beginning (switching on) of the stimulus, others - to its end (switching off), others - to the beginning and end, others are characterized by continuous impulses, and others are inhibited by the action of the stimulus. . This specialization, as well as the existence of elements with different sensitivity thresholds, provide a kind of “filtering” of irritations and contribute to a more subtle analysis of the external world.

A characteristic feature of the sense organs is functional mobility, i.e. the ability to react not with the entire mass of constituent elements, but fractionally, partially. This property is one of the mechanisms for establishing the optimal functioning of the senses (P. G. Snyakin).

When exposed to irritants (for example, light or sound), the sensitivity of the sensory organs decreases; upon the cessation of their action or in their absence (darkness, silence) it is observed reverse process increasing the sensitivity of the senses. A change in the sensitivity of the sense organs under the influence of irritation is called adaptation (see). It depends both on changes in the influx of afferent impulses from receptors, and on changes in the functional state of overlying nerve structures.

Afferent impulses from receptors enter the cortical representation of the sensory organs through both specific and nonspecific pathways; the latter are associated with the reticular formation (see) of the brain. In the cerebral cortex (see), the sense organs are represented by primary projections, or nuclei (visual, gustatory, auditory, etc.), and zones of overlap of cortical projections, where impulses from different sense organs are received. Most cortical neurons respond to the arrival of impulses of a certain modality (gustatory, mechanical, temperature); only a small number of neurons are capable of responding to impulses of different modalities. The presence of zones of overlap of cortical projections is one of the mechanisms for the interaction of sensory organs, combining and synthesizing information coming from various receptors. The sense organs do not function in isolation, but have an inhibitory or activating effect on each other. The versatility of objects and phenomena of the external world reflects complex work sense organs, underlying objective perception.

The functioning of the sense organs is not limited to the receipt of afferent impulses from receptors and deciphering their code into nerve centers brain, and also includes the response influences of the centers on the perceptive apparatus. These influences, reflexive in nature, are in the nature of “tuning” the receptor apparatus for the best perception of irritations and can be carried out through special efferent fibers that are part of the sensory nerves, fibers of the autonomic nervous system, neurohumorally, as well as through the muscular reception apparatus. The reticular formation plays a major role in the regulation of receptors and neurons of the cortical projections of the sensory organs. Conditioned reflex regulation of the sense organs is also essential. The central regulation of sensory influx underlies the efficiency of the work of nervous structures, the basis for the formation of a mechanism of temporary communication, performs the task of switching attention, recognition, etc. See also Taste, Vision, Smell, Touch, Hearing.