Inner ear: its structure and functions, as well as the mechanism of
How does the inner ear in humans?
The inner ear is one of the sections of a person’s ear. Due to the specific appearance of the inner ear also called labyrinth. It sees the ripple, we send only the eardrum.
The inner ear is the mediator between the outside world and the brain. In the inner ear are the most important elements of the whole of human hearing system.
Features of the structure of the inner ear
The ear is a complex organ of the human senses. Is the machine perception of sound, and control of body orientation in space. This paired organ located in the temporal bones of the skull. Anatomically divided into three subdivisions:
- The outer ear consisting of the auricle and the external auditory canal.
- The middle ear with the tympanic cavity with the auditory ossicles.
- Inner ear. In structure it is more complicated than the first two.
Part of the inner ear consists of bony and membranous labyrinths. Hollow elements connected to each other to form the bony labyrinth. Special attention deserves the protection of this organ from external factors.
He is so firmly buried in the bone, between it and the pyramid absolutely no space. Inside is membranous labyrinth, it is perfectly follows the shape of bone, but smaller in size.
Than filled the cavity of the inner ear:
- Endolymph – clear, viscous substance circulates in the membranous labyrinth.
- The perilymph fills the space between the maze called perilymphatic.
Interestingly, the whole labyrinth is a system of fluids and hypersensitive cells, which are responsible for sound perception and spatial orientation.
Anatomy of the inner ear has three major parts:
- semicircular canals.
The threshold is the center of the maze. Behind this cavity connects with the tubes of the semicircular canals, on the side wall of the vestibule has two holes. The first oval window is sealed with the stapes, and the round, communicating with a spiral canal of the cochlea, has a secondary eardrum.
Predgornaya part contains two connected education: elliptic and spherical saccules. They are filled with lymph, and their walls are covered with special voloskovye cells.
The peculiar structure of the cochlea is that it is a spiral hollow channel, wrapped around the bone core. In this rod are longitudinal channels with voloskovye and reference cells, which are the basis of the organ of Corti.
The length of the cochlea is a spiral bone plate. It divides the cavity of the cochlea into two moves:
- on the top – predgornaya stairs;
- on the lower tympani.
The bottom of the spiral canal of the cochlea is covered the main membrane. Drum and predgornaya of the ladder is the outer channels, interconnected at the apex of the cochlea. The volute channel is a fluid, endolymph, perilymph makes the ladder of the vestibule and drum the stairs.
Semicircular canals start from the vestibule: front, rear and lateral. Three in each ear, they are in the same planes and have the shape of arcs. The legs of the arcs are closed in anticipation of an elliptical shaped pouch.
The feature of the structure of the semicircular canals is that one leg of each arc expands vial attached to the pouch. The front and rear channels are fused at the base and have a common exit into the vestibule.
The function of the inner ear
Likely that the internal ear, its structure and functions have undergone evolution. The modern man it performs two functions:
- The auditory function. The processes responsible for auditory perception, occur in the cochlea.
- Orientational function. For the orientation in space of the responsible semicircular canals and the vestibule.
The auditory element
Moving Andolini in the canal of the cochlea causes tremors of the membrane in the round window. For drum and preddverno stairs moves the perilymph. Fluctuations in the SAG areas of the membrane and irritate the hair cells the organ of Corti. The transformation of sound signals into nerve impulses — the main task of the organ of Corti.
The brain, which received impulses, analyzes the information and the person understands what he heard. Hair cells, combined with the tips of the nerve fibers form the nerve, leaving the organ of Corti. Accordingly, the cochlea is the auditory portion of the inner ear.
Interestingly, certain sounds react different areas of the membrane. In the apex of the cochlea it senses low sounds at the base are high.
The vestibular apparatus
Working on the principle of building level, the vestibular system helps us maintain balance. Perform this function semicircular canals and the vestibule, they have a very complex system. In ampoules the arcs of the semicircular canals placed receptors scallops.
In function they are similar voloskova the cell membrane of the cochlea. Scallops is the kinetic receptors, that is they perceive angular acceleration (head movement). Receptors are irritated a moving jelly-like substance.
At linear acceleration (orientation in space) aktiviziruyutsya receptors in the sacs of the vestibule, the so-called otolith apparatus. Linear acceleration causes the movement of the endolymph, irritant receptors, which nerve fibers transmit information to the brain. Further, the brain collects and analyses all information received. If visual and auditory information do not match, the person feels dizziness.
The ear is a complex and important organ. In order to avoid various diseases that lead to decrease and hearing loss, should pay due attention to their ears. To keep clean the surface of the ears, do not SuperCool and not too much loud sounds – the best advice to maintain good hearing.