The auditory analyzer plays an important role in human perception of the environment. With the help of hearing, people communicate, exchange information. Learning to speak is associated with hearing. Through the organ of hearing, a person receives signals about what is happening in the environment.
The peripheral section of the auditory analyzer is represented by the organ of hearing, that is, the ear. The outer ear, middle ear, and inner ear are isolated. The outer and middle ear are auxiliary formations that ensure the transmission of sound vibrations to the inner ear, where sound vibrations are converted into nerve impulses.
The outer ear consists of the auricle, the external auditory canal, and the tympanic membrane. The auricle is formed by cartilage covered with skin. It directs sound waves into the ear canal to the eardrum. The eardrum is a thin membrane that separates the outer ear from the middle ear, which picks up sound vibrations and transmits them to the middle ear.
The middle ear is represented by the tympanic cavity. It contains the auditory ossicles (malleus, incus and stapes), which are interconnected by joints. The auditory ossicles amplify the auditory vibrations and transmit them to the membrane of the oval window of the inner ear. The middle ear is connected by the auditory (Eustachian) tube with the nasopharyngeal cavity. The function of the eustachian tube is to balance the pressure on the eardrum. …
The inner ear is located in the temporal bone and is represented by the bony and membranous labyrinth. Only a part of this section – the cochlea – belongs to the organ of hearing. The cochlea contains the organ of Corti – the receptor part of the organ of hearing. The snail is filled with liquid. The hair receptor cells of Corti’s organ perceive fluid vibrations and generate a nerve impulse.
The nerve impulse is transmitted along the auditory nerve to the auditory area of the cerebral cortex, located in the temporal lobe. There, the recognition of sounds and the formation of sensations takes place.
Balance organ (vestibular apparatus)
The vestibular apparatus perceives the position of the body in space. It is located in the inner ear and is represented by three semicircular canals and a vestibule, consisting of two sacs. In the semicircular canals, there are receptor hair cells that respond to rotational movements. In the cavity of the vestibule there are otoliths – numerous crystals of calcium carbonate – and on the inner walls of the sacs there are receptors that perceive acceleration or deceleration of movement.
The impulses are transmitted along the vestibular nerve to the central nervous system, where they are analyzed. Many parts of the central nervous system are responsible for the position of the body in space, but this is mainly the function of the cerebellum.
Muscles, tendons and joints contain receptors that control the degree of muscle stretching. The excitement arising in them enters the cerebellum and the parietal lobe of the cerebral cortex. There, a sense of the position and condition of the muscles of the body and its various parts is formed and coordination of all movements is carried out.
The muscular sense allows you to control and control your movements. Thanks to this feeling, we are able to perform many complex actions every day without thinking, automatically. Without it, a person would not be able to perform any complex movement. Muscular feeling plays an important role in the work of people of such professions as painter, surgeon, turner, driver.