How long is the ear canal

Ears are an important source for people to hear sounds and obtain information. The ear is mainly divided into the inner ear, outer ear and middle ear. The ear canal we often refer to usually refers to the external auditory canal. The external auditory canal and the auricle are collectively called the external ear. The depth of the ear canal is generally 2.5 cm to 3.5 cm. Generally, children's ear canals are deeper. At the deepest part of the ear canal, there are some membranes called eardrums, which are relatively fragile.

The external ear refers to the part of the ear that can be seen from the outside of the human body, namely the auricle and the external auditory canal.

The middle ear consists of the tympanic membrane, the middle ear cavity and the ossicular chain. The inner ear is located in the petrous part of the temporal bone and includes the semicircular canals, vestibule, and cochlea. The semicircular canals can sense movement in all directions and play a role in regulating body balance. The cochlea is a snail-shaped structure surrounded by the skull.

The cochlea is filled with fluid and separated by the basilar membrane. Located above the basilar membrane is the spiral organ, a structure that collects nerve electrical impulses. A cross-section of the cochlea shows the structure of the spiral organ.

The sound we hear is actually produced by a sound-making body.

There are vibration waves and sound waves within a certain frequency range. The human auricle is like a satellite receiver that can receive sound waves and gather them to the external auditory canal. Then, they are transmitted to the eardrum, causing the eardrum to vibrate. In this way, the sound energy of the sound waves is converted into mechanical energy. The vibration of the eardrum can drive the auditory bones connected to it, and the movement of the auditory bones can vibrate the portal of the inner ear - the oval window membrane.

This causes the lymph fluid in the inner ear to vibrate.

This causes the basilar membrane of the inner ear to vibrate, stimulating the cells on the basilar membrane to produce corresponding changes in electrical potential. At this time, the mechanical energy is converted into biological signals. This electrical signal converges on the auditory nerve and is then transmitted to the auditory center in the brain through the auditory nerve.

Only then can people truly "hear" the sound.

The auditory center is like an intelligence research institute, which classifies, numbers, analyzes and organizes the incoming bioelectric signals. Only then can the brain understand the meaning of the received sound waves and then respond. Although we have talked about it a lot, in fact this process is completed in a very short time, only a few thousandths of a second, and you can't even notice it.