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Keywords: the analyzer, Pavlov, doctrine Pavlova about analyzers, vision, hearing, an olfaction, visual, olfactory, acoustical, analyzers, a lens, a vitreous, cranial nerves, kortiev an organ

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FUNCTIONAL ANATOMY OF ANALYZERS

The external world environmental the person, is learnt by means of sense organs. Sense organs perceive not only the borings going from internal medium of an organism. As a result of a boring of sense organs in the big hemispheres of a brain there are sensations, perceptions, representations. Only through sensations the person is guided in an environment. The complex nervous devices perceiving and analyzing borings, acting from external and internal medium of an organism, I.P. Pavlov has named analyzers. The analyzer, on I.P.Pavlovu, will consist of three departments closely connected among themselves: peripheric, conduction and central. Receptors are a peripheric part of the analyzer. They are submitted by the nervous cells reacting to certain changes in an environment. Receptors are various on a structure, a site and functions. Some receptors look like rather simply arranged nervous terminations, or they are separate elements of difficultly arranged sense organs, as, for example, retinas of an eye. Centripetal the neurones conducting ways from a receptor up to a bark of the big hemispheres, make a conduction department of the analyzer. Sites of a bark of the big hemispheres of the brain, perceiving the information from corresponding receptor formations, make the central part, or a cortex department of the analyzer. All parts of the analyzer operate as a unit. Infringement of activity of one of parts causes infringement of functions of all analyzer. Distinguish visual, acoustical, olfactory, gustatory and dermal analyzers, a motor analyzer which receptors are in muscles, tendons, joints, and the vestibular analyzer, his receptors are irritated at change of a position of a body.

Analyzers

In 1904 Academician P.P.Lazarev at session of the Scientific organization for the first time showed the phenomenon of intensifying of sound perception under action of light. Before an audience in a hall the screen periodically shined and replaced was located. During illumination strongly enough sounding tuning fork was heard more loudly, than during blackout of the screen. In S.V.Kravkova's experiences function of the visual device essentially varied under action under action of a sound boring. Ability to distinguish dark objects on a light background improved, and light on dark - was reduced. Musicians mark the fact of intensifying of loudness of sounds at illumination, therefore for the best perception of music in concert halls usually extinguish light. Interactions of analyzers it is shown and in joint sensations. Cryesthesias, " running on a skin murashek " from a gnash a knif on glass. Here on the person the sound irritant - a gnash operates; He hears it, but simultaneously there is a cryesthesia - it is joint sensation. Sounds cause the various painted, color sensations in musicians. It enables them will designate various color character of those or other sounds. There are people which at action of light irritants have acoustical sensations. Interaction of analyzers is caused by transition of exaltation from centripetal ways of one analyzer on another. The interrelation of analyzers is very important when the person by virtue of the various reasons loses this or that kind of sensitivity (blindness, deafness, etc.). At blind absence of vision is compensated by an exacerbation of a taction and hearing. Using an olfaction, slepogluhonemye are capable to count amount of people which are taking place in a room.

the Structure and functions of an organ of vision. Hygiene of vision

The eye is posed in an excavation of a skull - an orbit. Behind and from sides he is environmentproofed by osteal walls of an orbit, and in front - blepharons. The internal surface of blepharons and a forward part of an eyeglobe, except for a cornea, are covered with a mucosa - a conjunctiva. At external edge of an orbit plaintive Ferri lactas which allocates a liquid protecting an eye from a desiccation is posed. In regular intervals distribution of a plaintive liquid on a surface of an eye is promoted by a nictitation of blepharons. The form of an eye ball-shaped. At adults diameter of it makes about 24 mm, at newborns - about 16 mm. The form of an eyeglobe at newborns more ball-shaped, than at adults. As a result of such form of an eyeglobe newborn children from 80 up to 94 % of cases have a hyperope refraction. Body height of an eyeglobe proceeds after a birth. Most intensively it grows first five years of life, less intensively - till 9-12 years. The eyeglobe will consist of three environments - external, average and internal. An external environment of an eye - a sclera, or belochnaja an environment. It is a dense opaque tissue of white color, thickness about 1 mm. In a forward part it passes in a transparent cornea. The sclera at children is more thin and has the increased extensibility and an elastance. It promotes mild deformation of an eyeglobe that is important in formation of a refraction of an eye. The cornea at newborn children to thickness also is more convex. By five years thickness of a cornea decrease, and the radius of curvature of it with the years does not vary almost. With the years the cornea becomes more dense and its refracting force decreases. Under a sclera the vascular environment of an eye is posed. Thickness of it of 0,2-0,4 mm. It contains a plenty of blood vessels. In a forward department of an eyeglobe the vascular environment passes in ciliary (tsiliarnoe) a body and an iris of the eye (iris). In a ciliary body the muscle connected to a lens and regulating his curvature is posed. The lens is the transparent elastic formation having the form of a biconcave lens. The lens is covered with a transparent bag; on all to his edge to a ciliary body very resilient fibers are pulled thin, but. They are strongly tense and hold a lens in the stretched condition. The tissue of an iris of the eye contains special staining substance - a melanin. Depending on amount of this pigment color of an iris changes from grey and blue up to brown, almost black. Color of an iris determines color of eyes. At absence of a pigment (people with such eyes name albinoes) rays of light will penetrate into an eye not only through a pupil, but also through a tissue of an iris. At albinoes of an eye have a reddish shade. At them the disadvantage of a pigment of an iris is frequently combined with an insufficient xanthopathy and hair. Vision at such people is lowered. Between a cornea and an iris, and also between an iris and a lens there are the small spaces termed according to forward and back chambers of an eye. In them there is a transparent liquid - a watery moisture. It supplies with nutrients cornea and a lens which are deprived blood vessels. The cavity of an eye behind of a lens is filled with transparent jelly-like mass - a vitreous. The internal surface of an eye is covered thin (0,2-0,3 mm), rather complex environment on a structure - by a retina, or a retina. It contains the photosensitive cells named because of their form cones and rods. The nervous fibers departing from these cells, gather and form an optic nerve which is referred to a brain. Light beams acting in an eye before they will get on a retina, pass in some refracting mediums. The cornea, a watery moisture of forward and back chambers of an eye, a lens and a vitreous concern to them. Each of these mediums has the parameter of optical force which is expressed in diopters. 1äïòð is an optical force of a lens with a focal length 1ì. Optical force of a cornea makes 43 dptr, a lens - 19 dptr, the system of an eye is peer as a whole 59 dptr at examining far subjects and 70,5 dptr at examining close subjects. An eye - extremely complex optical system. And for simplification such model of an eye in which one convex surface gives a cooperative effect of a diffraction of beams in all to complex optical system of an eye has been offered.

That the considered subject has been clearly seen, it is necessary, that beams from all his points have got on a back surface of a retina, i.e. here have been focused. When the person looks afar, the subjects posed on close distance, seem indistinct, they not in focus. If the eye fixes close subjects, are not clear visible remote. Try to see clearly simultaneously equally a font of the book through a gauze grid and a gauze grid. It will not be possible to you, since subjects are posed from an eye on different distance. The eye is capable to adapt to precise vision of the subjects which are taking place from him on various distances. This ability of an eye name an accommodation. It is carried out by change of curvature of a lens. At examining close subjects the lens is done by more convex due to what beams from a subject converge on a retina. The lens by means of a zinc sheaf paired to a muscle, locating a wide ring behind of a root of an iris of the eye. Due to activity of this muscle the lens can change the form, become more or less convex and accordingly stronger or more weak refract rays of light getting in an eye. At examining the subjects which are taking place on far distance, the ciliary muscle is weakened, and a sheaf, attached mainly to a forward and back surface of a capsule of a lens, at this time are tense, that causes squeezing a lens in front back and his extension. Therefore at a view afar curvature of a lens and, hence, refracting force of it become the least. At approach of a subject an eye there is a reduction of a ciliary muscle, the sheaf is relaxed. It stops squeezing and extension of a lens. Owing to an elastance the lens becomes more convex and his refracting force is enlarged. The least distance from an eye on which the subject is still distinctly seen, name the nearest point of clear vision. At a normal eye the distant point of clear vision lays in infinity. The senile hyperopia is caused by a distance of the nearest point of clear vision owing to loss by a lens of an elastance and corresponding decrease of his refracting force. With the years there is a change of an accommodation. The reason of it is inspissation of a lens. He becomes all less elastic and gradually loses ability to change the form. Accordingly decreases and refracting force of a lens. It is already not enough of it for clear vision of close subjects, glasses are necessary. Dropping of size of an accommodation begins with 10-years age though practically it does not affect vision for many years. A refraction name a refractivity of an eye at rest of an accommodation when the lens as much as possible impressed. Distinguish three kinds of a refraction of an eye: proportional (emmetropicheskuju), hyperope (gipermetropicheskuju) and mope-eyed (miopicheskuju). In an eye with a proportional refraction the parallel beams going from far subjects, are stopped on a retina, distinct vision of a subject thus is provided. For reception on a retina of clear images of subjects posed close such eye should strengthen the refractivity due to a strain of an accommodation, i.e. by augmentation of curvature of a lens. Than closer there is a considered subject, the lens should become especially convex to transfer the focal image of a subject on a retina. The hyperope eye has concerning a weak refractivity. In such eye the parallel beams going from far subjects, are crossed behind a retina. In a mope-eyed eye the parallel beams going from far subjects, are stopped ahead of a retina, not reaching up to it. It can be connected to too long longitudinal axis of an eye or with the greater, than normal, refracting force of mediums of an eye (curvature of a lens is more). The mope-eyed eye well sees only subjects posed close. At a myopia appoint glasses with disseminating biconcave glasses which transform parallel beams in missing. The myopia in the majority a case it congenital, however, is enlarged at school age from elementary grades to grown-ups. In serious cases the myopia is accompanied by changes of a retina that conducts to falling vision and even otsloeniju retinas. Therefore well-timed carrying of glasses by people, suffering a myopia, is obligatory.

Impossibility of a convergence of all beams in one point, focus, name an astigmatism. It is observed usually at unequal curvature of a cornea in its various meridians. Normal eyes too have a small degree of an astigmatism, as a surface of a cornea not strictly spherical: by treating from distance of the best vision of a disk with the concentric circles put on him insignificant flattening circles is observed. The sharp degrees of an astigmatism breaking vision, are corrected by means of cylindrical glasses which settle down on corresponding meridians of a cornea. For judgement about ability of an eye to distinguish the form and size of a considered subject uses concept of visual acuity. Visual acuity - ability to distinguish the least distance between two points which is reached when between two excited cones there is one not excited. As a criterion of visual acuity the angle which is formed between the beams going from two points of a subject to an eye, - an angle of vision serves. The less this angle, the above visual acuity. Normal vision is carried out by two eyes - a solid vision. It allows to feel relief images of subjects, to see depth and to determine distance of a subject from an eye. At vision 2-ìÿ eyes on a retina of each eye the image of a considered subject turns out. However the person perceives a subject single. It occurs because, that the image of a subject arises on identical points of a retina. Identical points of a retina of two eyes name areas of the central fossas and all points posed from it on identical distance and in the same direction. Incoincident points of a retina name not identical. If beams from a considered subject will get on not identical (not respective) points of retinas images of a subject it appears bifurcated. Vision two eyes facilitates perception of space and depth of a locating of a subject. At examining a subject serially that one other eye we see the different sides of it, that gives representation about dimensions of a subject. The perception of movement of a subject in case of a motionless eye depends on movement, moving his images on a retina. Perception of moving subjects at simultaneous movement of eyes and heads and definition of rate of movement of subjects are caused not only visual, but also centripetal impulses from proprioretseptorov eye and cervical muscles.

the Retina represents the internal environment of an eye having complex, laminated frame. Here two kinds of receptors - rods and cones are posed. These are photoceptors. Light beams from considered subjects, pronikaja through a pupil in an eye, operate on photosensitive cells of a retina and cause in them nervous exaltation which is transferred on an optic nerve in the cortex center of vision posed in occipital shares of a brain. In a bark of a brain there is very complex process of processing of the visual information as a result of which there is a visual sensation. In a mesh environment it is totaled about 125 million rods and 6 million cones. The main mass of cones is concentrated in the central area of a retina - in a macula lutea. On a measure of erasion from center the number of cones decreases, and rods grows. On periphery of a retina there are only rods. Cones are intended for day time vision. They are insensitive to weak illumination. They perceive the form, color and details of subjects. Rods perceive light beams in conditions of twilight illumination. The macula lutea, is especial his central fossa consisting only from cones, is a place of the best vision. Such visions refers to central.

the Structure and functions of an ear

the Ear perceives fluctuations of air medium. At the person and the supreme vertebrate animals this organ is detached from other sense organs. Ears are connected in all fauna to organs of conservation of equilibrium which participate in maintenance of the certain pose of a body. The equilibriums which have lost sensation the animal, having started to move, immediately would turn over on a back or sideways. Receptor devices - acoustical and vestibular - are posed in an internal ear. In filogeneze they have the general parentage. Both receptor devices innervirujutsja fibers 8 steams of cranial cerebral nerves. Both are raised by mechanical fluctuations: the vestibular device perceives angle acceleration, acoustical - air fluctuations. The organ hearing is a part of the system providing ability to articulate speech. Acoustical perceptions in development of the person so closely contact speech, that the child who has lost hearing in the early childhood, loses also speech ability though all articulation device at him remains not broken.

Acoustical receptors are in a cochlea of an internal ear which is posed in a pyramid of a temporal bone. Sound fluctuations are transferred to them through the whole system of the auxiliary formations providing perfect perception of sound borings. The ear of the person will consist of three parts - an external, average and internal ear.

the External ear will consist of an auricle and external acoustical passage. The external ear serves for catching sounds. The auricle is formed elasticheskim by a cartilage outside covered with a skin. Below the auricle is added dermal skladkoj - mochkoj which is filled with a fatty tissue. At animals the concha is mobile, that enables them to catch a direction of a sound. At the person aural muscles are weakly advanced also an auricle is almost motionless. Definition of a direction of a sound at the person is connected with so-called binauralnym hearing, i.e. with earing two ears. Any sound going sideways, acts in one ear earlier on some share of a millisecond, than in another (depending on a site of a source of a sound). The difference in time of arrival of the sound waves perceived by the left and right ear, enables the person to define a direction of a sound. If at the person one ear is struck and does not function, he determines a direction of a sound rotation of a head. External acoustical passage at the adult person has length of 2,5 sm, capacity 1 from m a cube. Acoustical passage is covered by a thin skin with thin hairs and modified potovymi Ferri lactases, developing an earwax. The earwax will consist of the fatty cells containing a pigment. Hairs and an earwax carries out a protective role. On border between external and a middle ear there is an eardrum. It is thin soedinitelno-tkannaja a plate (its thickness about 0,1 mm) which outside is covered with an epithelium, and from within a mucosa. The eardrum is posed naklonno and starts to change, when on it fall on the part of external acoustical passage sound fluctuations. And as the eardrum has no own period of fluctuations it changes at any sound according to his wavelength.

The middle ear is submitted by the drum-type cavity having the wrong form as a small flat drum on which the shaking membrane is hardly tense, and an acoustical tube. Inside a tympanic cavity acoustical bonelets jointed among themselves - a hammer, an anvil and a stirrup are posed. The internal ear is separated from average by a membrane of an oval window. The handle of a hammer is twisted in an eardrum; the hammer paired by other end to an anvil, and last with the help of a joint movably paired to a stirrup. The muscle holding it at a membrane of an oval window of a vestibule is attached to a stirrup stremennaja. The system of acoustical bonelets provides augmentation of pressure of a sound wave by transfer from an eardrum on a membrane of an oval window approximately at 30-40 time. It is very important, as even the weak sound waves falling on an eardrum, in result it appears capable to overcome resistance of a membrane of an oval window and to transfer fluctuations in an internal ear, being transformed there in fluctuations of a liquid - endolymphs. The drum-type cavity paired to a nasopharynx by means of acoustical (evstahievoj) tubes in length of 3,5 sm and very narrow (2 mm). The tube supports identical pressure outside and from within - on an eardrum that frames optimum conditions for its fluctuation. The aperture of a tube in a pharynx usually is in a slept condition, and passage of air to a drum-type cavity occurs during the act of a swallowing and yawn when the lumen of a tube and pressure in a pharynx opens and a drum-type cavity is leveled.

The internal ear is posed in a petrous part of a temporal bone and represents an osteal labyrinth inside which there is a webby labyrinth from a connecting tissue. The webby labyrinth is as though inserted into an osteal labyrinth and, in general, repeats his form. Between osteal and webby labyrinthes are present a liquid - a perilympha, and inside a webby labyrinth - an endolymph. In a wall separating a middle ear from internal, except for an oval window, there is still a round window which makes possible fluctuation of a liquid. The osteal labyrinth will consist of three parts: in center - the vestibule, in front from him is a cochlea, and behind - semicircular canals. An osteal cochlea - spirally coiling canal forming two revolution around of a hinge of the pencil-point form. Diameter of the osteal canal at the basis of a cochlea of 0,04 mm, and at top 0,5. From a hinge the osteal spiral plate which divides a cavity of the canal into two parts, or ladders departs. Inside the average canal of a cochlea, in a cochlear course. Is zvukovosprinimajushchy the device - spiral (kortiev) an organ. Kortiev the organ has a basilar (basic) plate which will consist approximately of 24000 thin fibrous fibers of various length, very resilient and weakly connected with each other. On the basic plate along it in 5 series settle down basic and voloskovye sensory cells which is actually acoustical receptors.

For an acoustic analyzer the sound is an adequate irritant. Sound waves arise as alternating of condensations and underpressures of air which are distributed in all sides from a source of a sound. All vibrations of air, water or other resilient medium break up to periodic (tones) and acyclic (hums). If them to write down, tones have the correct, precise, rhythmic form, hums - wrong, complex. Tones are high and low. To the last there corresponds smaller number of fluctuations in a second. The basic characteristic of each sound tone is the length of a sound wave to which there corresponds the certain number of fluctuations in a second. Length of a sound wave determine in distance which passes a sound in a the second, divided on number of complete fluctuations which makes a sounding body in a second. The more number of fluctuations, the more shortly a wavelength. At high sounds a wave short, gauged in millimeters; at low - long, gauged in the meters. The highest sound which we in condition to hear, has 20000 fluctuations in a second; the lowest - 12-24 Hz. At many animals the top border of hearing is higher, than at the person. For the person sounds in 50-100 thousand fluctuations a second neslyshimy are ultrasounds. With the help of physical devices the person can cause and record ultrasounds.

Value of sense organs

The organism is connected to an external world with the help of sense organs. The affection or partial deenergizing of sense organs causes sharp downstroke of his activity in the person. Operating on our sense organs, subjects and the phenomena of world around cause sensations. With the help of analyzers the person learns world around. The role of analyzers in labour activity is especially great. In case of defeat of the majority of analyzers labour activity is practically impossible, the person is immersed in continuous dream. I.M.Setchenov has described the patient observed Botkinym at whom all sense organs have been struck, except for a taction and muscular feeling in the right arm. This patient continuously slept, if nothing irritated its right arm. If to limit entering in the central nervous system of borings from different sense organs or completely to exclude them the delay in development of a brain is observed, intelligence. The analysis of perceived borings begins already in a receptor part of the analyzer. Here there is the elementary analysis, and the boring is transformed during exaltation. More perfect analysis occurs in subcortical formations, result of that is performance of complex congenital acts (vstavanie, nastorazhivanie, turn of a head to a light source, a sound, maintenance of a position of a body, etc.) . The supreme, most thin analysis is carried out in a bark of the big hemispheres of a brain, in a cortex department of the analyzer. The big hemispheres are the supreme body the analysis and synthesis for irritants not only external, but also internal. However the majority of pulses from receptors of internal organs, reaching a bark of the big hemispheres, does not cause the mental phenomena. Such pulses name subsensory: they are lower than a threshold of sensations and consequently do not cause sensations. As a result of entering pulses from receptors of internal organs there is a self-regulation of respiration, a blood pressure, activity of heart, etc. The Healthy person usually does not feel the internal organs. Their signals in a bark of the big hemispheres change its functional a condition, but realized sensations do not cause (I.M.Setchenov it has named "dark" feeling). Only at diseases of internal organs or at essential changes of their condition (famine, thirst, etc.) There are realized sensations.

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Keywords: the analyzer, Pavlov, doctrine Pavlova about analyzers, vision, hearing, an olfaction, visual, olfactory, acoustical, analyzers, a lens, a vitreous, cranial nerves, kortiev an organ

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