In anatomical terms, three sections are distinguished in the human ear . 

  •                the outer ear, consisting of the auricle and the external auditory canal  
  •                the middle ear, composed of the tympanic cavity and having appendages – the Eustachian tube and cells of the mastoid process;     
  •                inner ear (labyrinth), consisting of a cochlea (part auditory), vestibule and semicircular canals (organ of equilibrium).       

If we attach to this the auditory nerve from the periphery to the cortex of the temporal lobes of the brain, then the whole complex will be called the auditory analyzer.

The auricle of a person consists of a skeleton – a cartilage covered with perichondrium and skin. The surface of the shell has a series of depressions and elevations. The muscles of the auricle in humans serve to maintain the auricle in its normal position. The external auditory meatus is a blind tube (about 2.5 cm long), slightly curved, closed on its inner end by the eardrum. At ADULT logo man outer third of the ear canal falls on the cartilage part and the inner two-thirds – of bone, which is part of the temporal bone. The walls of the external auditory meatus Venue lans skin, which in its cartilage section and the initial hydrochloric bone portion has hair and glands, highlighting guides viscous secret (earwax), and the sebaceous glands.

Tympanic membrane in the adult (10 mm in height and 9 mm wide) entirely of liruet outer ear fluids from it, i.e. from the drum by Lost. The handle of the malleus is rotated into the eardrum – part of one of the auditory ossicles.   

The drum cavity of an adult has a volume of about 1 cm ^; vystla on the mucous membrane; bone its upper wall borders the cavity of the skull, the front in the lower part passes into the eustachian tube, the rear in the upper part – the recess which connects the tympanic cavity with a cavity (cavern) paps prominent bone. The drum cavity contains air. It contains the auditory ossicles (Molo points, anvil, stapes) , connected Soest you, as well as two muscles (stirrups and tension members vayuschaya eardrum) and ligaments.    

On DNAs light on the internal wall has two holes Xia; one of them is an oval, closed stirrup plate edges koto swarm attached to the bone dies frame grained cloth, allowing the mobility of the stirrup; the other is round, tightened by the membrane (the so-called secondary tympanic).

Eustachian tube connects the drum hydrochloric nasopharynx cavity. It is usually in the sleeping state, swallowing pipe is open INDICATES and air passes therethrough into the tympanic cavity. 

In inflammatory processes in nasal pharyngeal mucosa lining the tube swells, the lumen tube is closed, stops camping air into the tympanic cavity, which causes a sense of laying and ear hearing loss.

Behind the tympanic cavity and the external auditory meatus are the cells of the mastoid process of the temporal bone, communicating with the middle ear, normally filled with air. With purulent inflammation of the tympanic cavity ( see otitis media ), the inflammatory process can go to the cells of the mastoid process ( mastoiditis).

The arrangement of the inner ear is very complicated, which is why it is called the labyrinth. It distinguish auditory part (snail) , which has the form of sea tion snails and forms a 2 1/2 curl, and so-called lead bulyarnuyu part, consisting of a tank, or before the doors , and three semicircular canals , located in three different planes. Inside the bone labyrinth, a membranous membrane is made, made of a transparent liquid. Curl across the lumen of the cochlea passes the plate that can vary, and it is located on the cochlear, or Corti organ containing auditory cells – perceiving the sound of the auditory analysis of the torus.

Physiology of hearing.

In the functional relation of the ear can inflate to pour into two parts: 

  •                sound-conducting (shell, external auditory meatus, eardrum and tympanic cavity, labyrinth fluid) and 
  •                zvukovosprinimayuschego (auditory cells, windows chania auditory nerve); to the sound-unit applies the entire auditory nerve, central nye wires and part of the cerebral cortex. Paul Noe defeat zvukovosprinimayuschego device leads to complete loss of hearing in this uha- Glu Hoth, and a sound-conducting – only a partial Noah (hearing loss).

Pinna in the physiology of a human ear is largely irrelevant, although it seems, in my opinion Gaeta orientation relative to the sound source in space. The external auditory meatus is the main channel through which the sound comes before Vai through the air with so-called. Air Provo gence; it can disrupt the hermetic Zak whipping (eg., sulfuric stopper ) lumen. In such cases, sound is transmitted to the labyrinth mainly through the bones of the skull (the so-called bone sound transmission).  

The tympanic membrane, hermetically separating the middle ear (tympanic cavity) from the outside world to protect it from atmospheric WHO contained in the spirit of the bacteria, as well as by cooling. The physio ogy ear tympanic membrane (as well as all associated auditory chain) is important for the transmission of low, ie, bass, ulcer.. Cove; the destruction of the ear or hearing to Stoczek low sounds are perceived poorly or not at all perceived, medium and high sly shatsya satisfactorily. The air contained in the tympanic cavity promotes mobility of the auditory ossicles chain n, in addition, it itself also conducts the sound of medium and low tones directly to the stapes plate, and maybe the secondary membrane of a round window. Muscles in the tympanic cavity are used to regulate the tension of the tympanic membrane and the chain of the auditory ossicles (adaptation to sounds of a different nature) depending on the strength of the sound. The role of the oval window is in the main transmission of sound vibrations to the labyrinth (its liquid). 

A role in the transmission of sound itself plays inner (labyrinthine) wall of the middle ear (ba Rab cavity).  

Through the Eustachian tube constant but it resumes air tympanum than atmospheric pressure is maintained therein encircling fluidized bed; this air undergoes gradual resorption. Furthermore, the tube serves to derive from the tympanic cavity in the nasopharynx of certain harmful substances – accumulated otde trolled accidentally trapped infection, etc. In the open mouth portion of the sound waves reaching the tympanic cavity through the tube..; this explains the fact that some hearing loss open their mouth in order to hear better.  

The labyrinth is of great importance in the physiology of hearing Sound waves traveling through the oval window and in other ways transmit vibrations of the labyrinth fluid of the vestibule, which in turn transfers them to the fluid of the cochlea. Sound waves passing through the labyrinth liquid cause its oscillation, which annoys the endings of the hairs of the corresponding auditory cells. This irritation, transmitted to the cerebral cortex, causes an auditory sensation.  

The vestibule and semicircular canals of the ear are the sensory organ, perceiving changes in the position of the head and body in space, as well as the direction of movement of the body. As a result of the rotation of the head or the movement of the whole body, the movement of fluid in semicircular channels located in three mutually perpendicular! planes, deflects hairs of sensitive cells in semicircular canals and this causes irritation of nerve endings; these irritations are transmitted to the nerve centers located in the medulla oblongata, causing reflexes. Severe irritations of the vestibule and semicircular canals of the vestibular apparatus (e.g., when the body rotates, rolls on ships or aircraft) cause dizziness, paleness, sweat, nausea, and vomiting. The study of the vestibular apparatus is of great importance in the selection of flight and maritime services.  

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