Human ear structure diagram and the physiological functions of the three parts

The physiological structure of the ear can be divided into three parts: the outer ear, the middle ear, and the inner ear, which connect the auditory nerve to the brain and constitute the human auditory system.

The structure of the ear enters the external auditory canal from the auricle of the outer ear, followed by the middle ear tympanic membrane (tympanic membrane);

There are three ossicles in the middle ear cavity, namely malleus, incus and stapes.The stapes touches the foramen ovale of the inner ear, and the sound is transmitted to the inner ear.

The structure of the inner ear can be divided into two parts.The cochlear part is auditory, the vestibular semicircular canal part is balanced, the cochlear part is assembled into the cochlear nerve, and the semicircular canal part is assembled into the vestibular nerve. These two nerves combine to form the cochlear vestibular nerve, which is the eighth pair of cranial nerves. The dried auditory nerve nucleus then reaches the auditory center of the brain.The main area of ​​the auditory center is in the temporal lobe of the brain.Therefore, the ear is only used to transmit sound, and ultimately the brain still has to listen to the sound.Each part of the auditory organ has its own unique function.

The sound we hear is actually a vibration wave _sound wave with a certain frequency range emitted by a certain sounding body.The human auricle is like a satellite receiver that can receive sound waves and converge them to the external auditory canal, and then pass to the tympanic membrane, causing the tympanic membrane to vibrate. In this way, the sound energy of the sound wave is converted into mechanical energy, and the vibration of the tympanic membrane can drive it. The connected ossicles, and the activity of the ossicles can vibrate the inner ear’s portal-the oval window membrane, which causes the lymph fluid in the inner ear to vibrate, which causes the inner ear basement membrane to vibrate and stimulates the cells on the basement membrane to produce it. Corresponding to the potential change, at this time, the mechanical energy is transformed into a biological signal. This electrical signal converges in the auditory nerve, and then is transported to the auditory center of the brain through the auditory nerve. Until then, the person can truly “hear” the sound.The listening center is like an information research institute, classifying, numbering, and analyzing and sorting out the bioelectric signals that come. The brain can understand the meaning of the received sound waves at this time, and then it can react.Although we have talked a lot, in fact this process was completed in a very short period of time, only a few thousandths of a second, and I couldn’t even notice it.

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