visual sensory system. Organ of hearing and balance. Analyzers of smell and taste. Skin sensory system.

The human body as a whole is a unity of functions and forms. Regulation of the body's life support, mechanisms for maintaining homeostasis.

Topic for self-study: The structure of the eye. Ear structure. The structure of the tongue and the location of the zones of sensitivity on it. The structure of the nose. Tactile sensitivity.

Sense organs (analyzers)

A person perceives the world around him through the sense organs (analyzers): touch, sight, hearing, taste and smell. Each of them has specific receptors that perceive a certain type of irritation.

Analyzer (sense organ)- consists of 3 departments: peripheral, conductor and central. Peripheral (perceiving) link analyzer - receptors. They convert the signals of the outside world (light, sound, temperature, smell, etc.) into nerve impulses. Depending on the mode of interaction of the receptor with the stimulus, there are contact(skin receptors, taste receptors) and distant(visual, auditory, olfactory) receptors. conductor link analyzer - nerve fibers. They conduct excitation from the receptor to the cerebral cortex. Central (processing) link analyzer - a section of the cerebral cortex. Violation of the functions of one of the parts causes a violation of the functions of the entire analyzer.

There are visual, auditory, olfactory, gustatory and skin analyzers, as well as a motor analyzer and a vestibular analyzer. Each receptor is adapted to its specific stimulus and does not perceive others. Receptors are able to adapt to the strength of the stimulus by reducing or increasing sensitivity. This ability is called adaptation.

visual analyzer. Receptors are excited by light quanta. The organ of vision is the eye. It consists of an eyeball and an auxiliary apparatus. Auxiliary device represented by eyelids, eyelashes, lacrimal glands and muscles of the eyeball. Eyelids formed by folds of skin lined from the inside with a mucous membrane (conjunctiva). Eyelashes protect the eye from dust particles. Lacrimal glands located in the outer upper corner of the eye and produce tears that wash the anterior part of the eyeball and enter the nasal cavity through the nasolacrimal canal. Muscles of the eyeball set it in motion and orient it towards the object in question.

Eyeball located in the orbit and has a spherical shape. It contains three shells: fibrous(outer), vascular(middle) and mesh(internal) and inner core, consisting of lens, vitreous body And aqueous humor anterior and posterior chambers of the eye.

The posterior part of the fibrous membrane is a dense opaque connective tissue albuginea (sclera), front - transparent convex cornea. The choroid is rich in vessels and pigments. It distinguishes actually choroid(rear end), ciliary body And rainbow shell. The main mass of the ciliary body is the ciliary muscle, which changes the curvature of the lens with its contraction. Iris ( iris) has the form of a ring, the color of which depends on the amount and nature of the pigment it contains. There is a hole in the center of the iris pupil. It can narrow and expand due to the contraction of the muscles located in the iris.

The retina is divided into two parts: back- visual, perceiving light stimuli, and anterior- blind, not containing photosensitive elements. The visual part of the retina contains light-sensitive receptors. There are two types of visual receptors: rods (130 million) and cones (7 million). sticks are excited by weak twilight light and are not able to distinguish color. cones excited by bright light and able to distinguish color. The sticks contain red pigment - rhodopsin, and in cones - iodopsin. Directly opposite the pupil there is yellow spot - the place of best vision, which consists only of cones. Therefore, we see objects most clearly when the image falls on the macula. Toward the periphery of the retina, the number of cones decreases, the number of rods increases. On the periphery are only sticks. The place on the retina where the optic nerve exits is devoid of receptors and is called blind spot.

Most of the cavity of the eyeball is filled with a transparent gelatinous mass, forming vitreous, which maintains the shape of the eyeball. lens is a biconvex lens. Its back is adjacent to the vitreous body, and the front is facing the iris. When the muscle of the ciliary body associated with the lens contracts, its curvature changes and the rays of light are refracted so that the image of the object of vision falls on the yellow spot of the retina. The ability of the lens to change its curvature depending on the distance of objects is called accommodation. If accommodation is disturbed, there may be myopia(the image is focused in front of the retina) and farsightedness(the image is focused behind the retina). With myopia, a person sees indistinctly distant objects, with farsightedness, near ones. With age, the lens thickens, accommodation deteriorates, and farsightedness develops.

On the retina, the image is inverted and reduced. Due to the processing in the cortex of information received from the retina and receptors of other sense organs, we perceive objects in their natural position.

auditory analyzer. The receptors are excited by sound vibrations in the air. The organ of hearing is the ear. It consists of the outer, middle and inner ear. outer ear consists of the auricle and ear canal. auricles are used to capture and determine the direction of sound. External auditory canal begins with the external auditory opening and ends blindly tympanic membrane which separates the outer ear from the middle ear. It is lined with skin and has glands that secrete earwax.

Middle ear It consists of the tympanic cavity, the auditory ossicles and the auditory (Eustachian) tube. tympanic cavity filled with air and connected to the nasopharynx by a narrow passage - auditory tube, through which the same pressure is maintained in the middle ear and the space surrounding the person. auditory ossicles - hammer, anvil And stirrup - connected to each other movably. They transmit vibrations from the eardrum to the inner ear.

inner ear consists of a bony labyrinth and a membranous labyrinth located in it. Bone labyrinth contains three sections: vestibule, cochlea and semicircular canals. The cochlea belongs to the organ of hearing, the vestibule and semicircular canals - to the organ of balance (vestibular apparatus). Snail- bone canal, twisted in the form of a spiral. Its cavity is divided by a thin membranous septum - the main membrane on which receptor cells are located. The vibration of the cochlear fluid irritates the auditory receptors.

The human ear perceives sounds with a frequency of 16 to 20,000 Hz. Sound waves travel through the external auditory canal to the eardrum and cause it to vibrate. These vibrations are amplified (almost 50 times) by the auditory ossicles and are transmitted to the fluid in the cochlea, where they are perceived by the auditory receptors. The nerve impulse is transmitted from the auditory receptors through the auditory nerve to the auditory zone of the cerebral cortex.

vestibular analyzer. The vestibular apparatus is located in the inner ear and is represented by the vestibule and semicircular canals. threshold consists of two bags. Three semicircular canals located in three mutually opposite directions corresponding to the three dimensions of space. Inside the sacs and channels there are receptors that are able to perceive fluid pressure. The semicircular canals receive information about the position of the body in space. The sacs perceive deceleration and acceleration, changes in gravity.

Excitation of the receptors of the vestibular apparatus is accompanied by a number of reflex reactions: a change in muscle tone, muscle contraction, contributing to the straightening of the body and maintaining the posture. Impulses from the receptors of the vestibular apparatus through the vestibular nerve enter the central nervous system. The vestibular analyzer is functionally connected with the cerebellum, which regulates its activity.

Taste analyzer. Taste buds are irritated by chemicals dissolved in water. The organs of perception are taste buds- microscopic formations in the mucous membrane of the oral cavity (on the tongue, soft palate, posterior pharyngeal wall and epiglottis). Receptors specific to the perception of sweet are located on the tip of the tongue, bitter - on the root, sour and salty - on the sides of the tongue. With the help of taste buds, food is tested, its suitability or unsuitability for the body is determined, when they are irritated, saliva and gastric and pancreatic juices are released. The nerve impulse is transmitted from the taste buds through the taste nerve to the taste zone of the cerebral cortex.

Olfactory analyzer. The olfactory receptors are irritated by gaseous chemicals. The organ of perception is the perceptive cells in the nasal mucosa. The nerve impulse is transmitted from the olfactory receptors through the olfactory nerve to the olfactory zone of the cerebral cortex.

Skin analyzer. Skin contains receptors , perceiving tactile (touch, pressure), temperature (thermal and cold) and pain stimuli. The organs of perception are the perceiving cells in the mucous membranes and skin. The nerve impulse is transmitted from the tactile receptors through the nerves to the cerebral cortex. With the help of tactile receptors, a person gets an idea of ​​the shape, density, temperature of bodies. Tactile receptors are most found on the fingertips, palms, soles of the feet, and tongue.

motor analyzer. Receptors are excited during contraction and relaxation of muscle fibers. The organs of perception are the perceiving cells in the muscles, ligaments, on the articular surfaces of the bones.

The structure of the eye The eyeball
optic nerve
The eyeball is made up of
3 shells that
surround the inner core
eyes representing him
transparent content -
vitreous,
crystal, watery
moisture in front and back
cameras.
vitreous body -
jelly-like texture
99% water and 1%
hyaluronic acid.

The structure of the eye

How does the ear hear?

vestibular apparatus

Olfactory organ - nose

Smells

Odor transmission mechanism

ALALIA - underdevelopment or lack of speech

APHASIA - inability to perceive speech

A person perceives the world around him through the sense organs (analyzers). There are visual, auditory, olfactory, gustatory, skin, vestibular and motor analyzers. Each analyzer contains receptors, perceiving the signal; nerve fiber, which conducts excitation from the receptor to the cerebral cortex and cortical area hemispheres, processing the received information.

The receptors of the visual analyzer are excited by light quanta. The organ of vision is eye, consisting of eyeball And auxiliary apparatus(eyelids, eyelashes, lacrimal glands, muscles of the eyeball). The eyeball contains three shells: fibrous (external), vascular and mesh, and lens, vitreous body And eye cameras filled aqueous humor(Fig. 26).

Rice. 26. The structure of the eye:

1 - cornea; 2 - iris;

3 - lens; 4 - retina;

5 - choroid;

6 - fibrous membrane;

7 - optic nerve;

8 - vitreous body

The posterior part of the fibrous membrane is an opaque sclera, the anterior part is a transparent convex cornea. The choroid in front forms a pigmented iris. In the center of the iris there is a hole - the pupil, which can change its size. Part of the choroid forms the ciliary muscle, which changes the curvature of the lens.

The back of the retina perceives light stimuli and contains visual receptors, rods and cones. The rods are responsible for black and white vision, the cones are responsible for color vision. Directly opposite the pupil on the retina there is yellow spot, the site of best vision containing only cones. On the periphery are located only sticks. The place in the retina where the optic nerve originates is called blind spot, it is devoid of receptors.

The lens is a biconvex lens. When the ciliary muscle contracts, its curvature changes, and the rays of light are refracted so that the image of the object falls on the yellow spot of the retina. The ability of the lens to change its curvature depending on the distance of the object is called accommodation. From the retina along the optic nerve, information is transmitted to the visual zone of the cerebral cortex, where it is processed, and a person receives a natural image of objects.

If the rules of visual hygiene are not observed, for example, when reading in a poorly lit room or lying down, visual impairment may occur. The most common of these disorders is myopia, in which accommodation is disturbed, the lens remains in a convex position, which makes it impossible to see distant objects clearly. Visual impairment can occur due to constant reading in transport, as well as due to the harmful effects of alcohol and tobacco. Another common visual impairment is farsightedness, which can be congenital or occur due to age-related flattening of the lens.

Hearing organ is ear, its receptors are excited by air vibrations. The human ear perceives sounds with a frequency of 16 to 20,000 Hz. It consists of the outer, middle and inner ear. The outer ear consists of the pinna and the ear canal. The eardrum separates the outer ear from the middle ear. The middle ear consists of the tympanic cavity, the auditory ossicles, and the Eustachian tube, which connects the tympanic cavity to the nasopharynx. The auditory ossicles, hammer, anvil, and stirrup are movably connected, and vibrations from the tympanic membrane are transmitted through them to the inner ear (Fig. 27). The ossicle system amplifies the vibrations of the tympanic membrane by 50 times. The vibrations of the auditory ossicles are transmitted by the fluid that fills the inner ear. The inner ear contains the cochlea, a bony canal twisted in the form of a spiral (Fig. 27). There are receptor cells in the cochlea that are excited by the vibration of the fluid in the cochlea. Nerve impulses are transmitted through the auditory nerve to the auditory zone of the cerebral hemispheres.

Rice. 27. Ear ossicles

(A) and general view

inner ear (B):

1 - hammer;

2 - anvil;

3 - stirrup; 4 - tympanic membrane; 5 - snail;

6 - round bag;

7 - oval bag;

8 – 10 - semicircular canals

The vestibular analyzer is located in the inner ear and is represented by oval and round sacs and semicircular canals (Fig. 27). Inside the sacs and channels there are receptors that are excited by fluid pressure. The semicircular canals perceive information about the position of the body in space, the sacs perceive deceleration and acceleration, a change in the direction of gravity. The vestibular analyzer is functionally connected with the cerebellum, which regulates its activity.

The taste analyzer is represented by taste buds located in the oral cavity and on the tongue. Taste buds are irritated by chemicals dissolved in water. With the help of taste buds, the suitability of food is tested; when they are irritated, digestive juices are released.

Olfactory receptors are located in the nasal mucosa, they perceive a variety of chemicals. From them, the nerve impulse is transmitted to the olfactory zone of the cerebral hemispheres, located in the insular zone.

Skin receptors perceive pressure, temperature changes, pain sensations. Skin analyzer receptors are located in the skin and mucous membranes. Most of them are on the fingertips, palms, tongue.

The motor analyzer transmits information about the state of muscles and the position of body parts to the brain. Its receptors are located in muscles, ligaments, on articular surfaces and are excited by contraction and relaxation of muscle fibers.

The concept of feeling

1. Feeling is a mental process of reflection of individual elementary properties of reality that directly affect our senses.

More complex cognitive processes are based on sensations: perception, representation, memory, thinking, imagination. Feelings are, as it were, the "gates" of our knowledge.

Sensation is the sensitivity to the physical and chemical properties of the environment.

Both animals and humans have sensations and the perceptions and ideas that have arisen on their basis. However, human sensations are different from animal sensations. A person's feelings are mediated by his knowledge, i.e. socio-historical experience of mankind. Expressing this or that property of things and phenomena in the word (“red”, “cold”), we thereby carry out elementary generalizations of these properties. A person's feelings are connected with his knowledge, the generalized experience of the individual.

Sensations reflect the objective qualities of phenomena (color, smell, temperature, taste, etc.), their intensity (for example, higher or lower temperature) and duration. Human sensations are as interconnected as the various properties of reality are interconnected.

Sensation is the transformation of the energy of external influence into an act of consciousness.

They provide a sensual basis for mental activity, provide sensory material for building mental images. Types of sensations

And skin. tactile And painful,

Subject, tasks and methods of developmental and educational psychology

The subjects of age psychology are: age dynamics, patterns, factors in the development of the human psyche at different stages of his life path. The subject of pedagogical psychology is the patterns of development of the human psyche in the conditions of training and education.

METHODS OF AGE PSYCHOLOGY ¢ ABOUT The main research methods used in developmental psychology are: ¢ observation, ¢ experiment, ¢ testing, ¢ survey, ¢ conversation ¢ analysis of activity products. Specific methods of age psychology: Twin method and Longitudinal method.

Tasks of developmental psychology:
- The study of the driving forces, sources and mechanisms of mental development throughout the life of a person.
- Periodization of mental development in ontogenesis.
- The study of age characteristics and patterns of mental processes.
- Establishment of age opportunities, features, patterns of implementation of various activities, the assimilation of knowledge.
- Study of the age development of the individual, including in specific historical conditions.
- Determination of age norms of mental functions, identification of psychological resources and human creativity.
- Creation of a service for systematic monitoring of the progress of mental health and development of children, assistance to parents in problem situations.
- Age and clinical diagnostics.
- Performing the function of psychological support, assistance in crisis periods of a person's life.

Analyzers as sense organs

The analyzer is a complex nervous mechanism that makes a subtle analysis of the surrounding world, that is, it singles out its individual elements and properties. Each type of analyzer is adapted to isolate a certain property: the eye reacts to light stimuli, the ear to sound stimuli, the olfactory organ to smells, etc.

Each analyzer consists of three sections: peripheral, conductive and central.

Peripheral department It is represented by receptors - sensitive nerve endings that have selective sensitivity only to a certain type of stimulus.

Receptors are outdoor, located on the surface of the body and perceiving irritations from the external environment, and internal, which perceive irritations from the internal organs and the internal environment of the body,

conductor department The analyzer is represented by nerve fibers that conduct nerve impulses from the receptor to the central nervous system (for example, the visual, auditory, olfactory nerve, etc.).

Central department The analyzer is a certain area of ​​the cerebral cortex, where the analysis and synthesis of incoming sensory information and its transformation into a specific sensation (visual, olfactory, etc.) takes place. It is here that sensations arise - visual, auditory, gustatory, olfactory, etc.

A prerequisite for the normal functioning of the analyzer is the integrity of each of its three departments.

In the cortical region of the analyzer, on the basis of the nervous process, a mental process arises - feeling. This is how “the transformation of the energy of external irritation into a fact of consciousness” takes place.

All departments of the analyzer work as a whole. There will be no sensation if any part of the analyzer is damaged. A person will go blind if the eye is destroyed, if the optic nerve is damaged, or if the work of the brain department - the center of vision is disturbed, even if the other two parts of the visual analyzer are completely preserved.

Sensation is a mental process of reflection of individual elementary properties of reality that directly affect our sense organs.

Depending on the nature of the stimuli acting on a given analyzer, and on the nature of the sensations arising in this case, separate types of sensations are distinguished.

First of all, it is necessary to single out a group of five types of sensations, which are a reflection of the properties of objects and phenomena of the external world - visual, auditory, gustatory, olfactory And skin. The second group consists of three types of sensations that reflect the state of the body - organic, sense of balance, motor. The third group consists of two types of special sensations - tactile And painful, which are either a combination of several sensations (tactile.), or sensations of different origin (pain).

ANALYZERS

THEME #11

The meaning and role of analyzers. A person perceives the phenomena of the environment and its effects with the help of the senses. All irritations that he receives and reach a certain intensity are the source of ideas about the environment, about the world around him, about what exists outside of us and independently of our consciousness.

The orientation of the body in the external environment, its movements are mainly associated with the higher sense organs.

Each analyzer consists of three parts: peripheral ~ receptor, an apparatus that perceives and converts (transforms) the energy of external stimulation into a nervous process; conductive- transmitting excitation to the center, consisting of centripetal nerve fibers; central, or cortical part of the hemispheres, represented by special cells of the cerebral cortex.

The peripheral part of the analyzer perceives strictly defined types of stimuli. For example, the organs of vision perceive light, the organs of hearing - sound, etc. This property is called the adequacy of the senses to irritants.

Analyzer properties. Each analyzer has the ability to adapt (adapt) to the perception of either stronger or weaker stimuli. In addition, in labor activity, in the process of studying a child at school, his analyzers are subjected to exercises, they get used to accepting and distinguishing even minor irritations. This is what happens with the development and sharpening of hearing in children who learn music from an early age.

Interaction of analyzers. Analyzers interact with each other. This contributes to a better feeling. Sometimes even lowering it. So, sunlight changes the excitability of the receptors of the skin, smell, and hearing. Too hot food seems less tasty, as a strong temperature effect weakens the function of the taste analyzer. Auditory stimuli (tones, noises) increase the excitability of the dark-adapted eye to green-blue rays and lower it to orange-red. Therefore, knowledge of the mutual influence of analyzer functions in normal practice is of great importance. Disturbances in the work of the analyzer (for example, loss of vision, hearing, etc.) make a person disabled.

Analyzers function not only with close mutual influence, but also with partial mutual substitution of each other. At the same time, temporary (conditioned reflex) connections are formed between their cortical centers, which make it possible to partially compensate for the lost analyzer. So, in the blind, due to the systematic simultaneous functioning of the auditory and motor-tactile analyzer, the ability to cognize the world around with the help of touch and hearing is developed.