What Is the Organ of Corti?

Helix, sonic sensor, also known as Corti's organ. Located in the cochlea of the inner ear, on the basement membrane of the labyrinth of membrane, an epithelial cell complex formed by hair cells and support cells. The dorsal membrane is in contact with the hair cells of the spiral organ and the hair cells are connected to the nerve fibers in the deep part. Nerve fibers reach the snail shaft through the spiral bone plate, and connect the spiral ganglia. The cochlear nerve consists of nerve fibers from the spiral ganglia and extends to the cochlear nucleus of the bulbus.
Cotti organ

Helix, sonic sensor, also known as Corti's organ. Located in the cochlea of the inner ear, on the basement membrane of the labyrinth of the membrane, an epithelial cell complex formed by hair cells and support cells. The dorsal membrane is in contact with the hair cells of the spiral organ and the hair cells are connected to the nerve fibers in the deep part. Nerve fibers reach the snail shaft through the spiral bone plate, and connect the spiral ganglia. The cochlear nerve consists of nerve fibers from the spiral ganglia and extends to the cochlear nucleus of the bulbus.

Chinese name

Screw

Foreign name

spiral organ

Screwer overview

The cover film is composed of a gel-like matrix and fine fibers, which is soft and elastic, and is in close contact with the hair of the hair cells. When the vibrations of the sound waves pass through the eardrum and the ossicles to the external lymphatics of the inner ear, the external lymphatics of the drum stage cause the basement membrane of the volute to oscillate, while the cover membrane is relatively stationary. The relative movement between the two causes the hair cells to bend, causing the hair cell potential to change, and the mechanical energy of sound vibrations is converted into electrical energy in the hair cells, causing nerve excitement.

Physiological function of screw

To understand the functions of the spiral organ and ampullate from the physiological function of the inner ear, although there are two functions, from a physiological point of view, if both are understood as a disguised "tactile" organ, the two organs with different divisions of labor are Can go a step further to simplify and unify the concept. The spiral device feels a glial lid on top of the cells. In recent years, it has been confirmed under scanning electron microscopy that the cilia of sensory cells are inserted into the glia of the cover membrane. When sound waves cause internal and external lymphatic vibration, the spiral device vibrates with the basement membrane.

At this time, the cilia of the sensory cells are mechanically pushed by the cover membrane, causing the cilia to be displaced. The cells convert mechanical energy into electrical energy, which is evoked by the auditory nerve to the auditory center. The mechanical stimulation of the cilia by the cover film is the most important link that causes hearing. Imagine that on the sensory cells, hearing cannot occur without a stimulating substance such as a cover film. This mechanical pushing action is similar to touching the hair with a finger to cause a tactile sensation. Therefore, the mechanical stimulation of the sensory cells of the cover by the cover membrane can be called a disguised tactile sensation. In the same way, the physiological mechanism of the ampulla when the body position is changed is also a tactile disguise. This is because the top of the ampullary crest surface sensory cells also have long cilia that are inserted into the gelatinous ampulla crest located on top of the ampullate crest. When the human body begins to rotate and suddenly stops, the endolymph in the tri-semicircular canal also moves with positive and negative angular acceleration as the head rotates. Due to the inertia, the endolymph directly impacts the ampulla of the ampulla by mechanical action. The top of the ampulla is shifted obliquely, and the sensory cell cilia inserted in the ampulla are also shifted. In this way, the stimulation of the endothelium is transmitted to the center to cause position sensation, and then the reflection causes body balance. Imagine that without the glial membrane of the ampulla (impacted by the impact of endolymph), you cannot accept the stimulus of body rotation, nor can it cause the hair cells to excite, that is, they will lose their sense of position. Therefore, Stimulation is also a tactile disguise.

Corti Cortical structure of corti's hair cells and cover membrane

Human perception and discrimination analysis of sound waves, many researchers agree that sound waves enter the cochlea through the vestibular window and become liquid waves, and the basement membrane vibrates up and down with this liquid wave. Corti's device and the cover membrane are based on the spiral plate edge as The fulcrum forms a complex, shearing movement. The static cilia are bent under pressure, and the sound wave is replaced by the physical characteristics of its Rumi phase with nerve impulses, which are then transmitted to the auditory center through the cochlear nerve. The tunica tissue is a membrane that extends outward from the vestibular lip of the cochlear spiral edge, covering the inner spiral groove and the spiral organs, floating in the endolymph. The tissue structure of the vestibular lip portion and the free margin portion of the cover membrane is the thinnest, which is equivalent to the thickest part above the screw. The cover film structure is mainly composed of fibers and jelly. Its surface can see radial fibers and meandering thick fibers, which have a strengthening effect. The free margin of the cover membrane has foot-like protrusions, and contacts H_ensen's cells during shaking. The underside of the cover film is a granular layer, that is, the reticular membrane surface has W-shaped indentations consistent with the arrangement of hair cells.

Noise deafness caused by screwdriver

Noise-induced deafness (NIHL) is a type of sensorineural hearing loss that is slowly progressive due to long-term noise stimulation. In addition to the specific damage to the human hearing system, noise can also affect nervous, cardiovascular, digestive, endocrine and other systems, causing headaches, dizziness, high blood pressure, indigestion, insomnia and other symptoms, which can cause people's Mental and psychological disorders.

Microdynamics theory: After the high-intensity noise is transmitted through the ossicular chain or worm window, it can cause strong internal and external lymph fluid flow to form vortices, cause shear and squeeze movements of the basement membrane and the cover membrane, and impact the cochlear spiral , Causing different levels of mechanical damage, such as damage to the hair cells and hearing hair, rupture of vestibular windows, perforation of the reticular layer, bleeding of capillaries, and even peeling of the spiral device from the basement membrane. Some scholars have found that these mechanical injuries can aggravate or secondary cause vascular and metabolic lesions.

Metabolism: Noise exposure can cause severe disorders of hair cells and supporter enzyme systems, leading to metabolic disorders in the oxygen and energy systems, cell degeneration, and death. Strong noise can cause systemic and local stress protective reactions, which significantly increase the body's glucocorticoid concentration and heat shock protein levels, leading to hypoxia in hair cells, metabolism tends to anaerobic fermentation process, and insufficient energy generation, and the spiral organ cannot Acoustic-electrical conversion is completed.