What is the function of the inner ear?

I believe that many people do not know that the human ear is divided into inside and outside. Only those who have studied relevant professional knowledge can have a better understanding of the structure of the human ear. Most people do not understand this knowledge. Generally speaking, the structure of the human ear is very complex. The outermost layer is called the outer ear, and the innermost part is called the inner ear. The inner ear has the most complex structure, and the inner ear plays the following functions.

Functions of the inner ear:

The auditory system has three main parts: the outer ear, the middle ear, and the inner ear. Among them, the inner ear is the most complex and important.

The structure of the inner ear is very complex and sophisticated, especially the spiral organ in the cochlea, which is the main part of hearing. It works together with the auditory nerve to transmit sound signals to the auditory center of the brain.

The inner ear cannot be separated separately like the ossicular chain. It has a series of ducts and cavities in it. These ducts and spaces are filled with two types of fluid: perilymph and endolymph. The inner and outer lymph fluids are separated by a membrane. The inner ear is divided into three parts: the semicircular canals, the vestibule, and the cochlea.

The semicircular canals maintain the body's balance, are responsible for rotational movement, and do not have hearing function. However, because the lymph fluid is continuous in the inner ear, balance problems that accompany hearing loss, such as vertigo and vomiting, are related to it.

The vestibule is small and irregular in shape, located behind the stapes base within the oval window. The vestibule, as its name implies, is where the semicircular canals, the stapes base, and the cochlea converge. They are both filled with lymphatic fluid, and they both contain the sensory endings of the vestibular nerve, which is a branch of the auditory nerve.

The cochlea, as the name suggests, is coiled like a snail. The stapes base moves in the oval window, vibrating the perilymph in the vestibule. When the stapes footplate pushes the lymph inward, the final destination of the lymph is the oval window. We all know that the structure of the inner ear is very complex and sophisticated, especially the spiral organ in the cochlea. The spiral organ is composed of a plexus of microvessels. The vascular plexus secretes lymph fluid and is the main source of the chemical components of endolymph, which is a necessary substance for maintaining the function of hair cells. The spiral organ is composed of supporting cells, inner hair cells, outer hair cells and gelatinous tectorial membrane. Hair cells are auditory cells, which are arranged in order from outer hair cells and inner hair cells. It is generally believed that outer hair cells are more sensitive than inner hair cells. At the base of the hair cells are nerve endings, which can generate nerve impulses once triggered. Nerve impulses are transmitted along nerve fibers. Multiple nerve fibers form spiral ganglia. Multiple spiral ganglia gather like cables to form the cochlear nerve, which transmits electrical-chemical energy. The vestibular and cochlear nerves eventually merge into the auditory nerve.

Pathological changes in the inner ear and auditory nerve caused by various reasons are collectively referred to as sensorineural hearing loss.