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How does the organ of Corti convert sound vibrations into nerve impulses?

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Diagram showing auditory mechanisms in insects, including labeled illustrations of a scolophore organ, the mosquito ear with antenna shaft and scolophores, the cicada ear with auditory capsule and tympanic membrane, and the grasshopper ear with sensory body and tympanic membrane. — sound reception Auditory mechanisms in insects. (Left) A scolophore organ. (Top right) The mosquito ear. (Centre right) The ear of the cicada *Magicicada septendecim*. (Bottom right) The ear of the grasshopper.

The organ of Corti converts mechanical sound vibrations into nerve impulses through a process of transduction involving specialized sensory hair cells.12

When sound waves cause the basilar membrane to vibrate, the organ of Corti moves against the tectorial membrane. This movement creates shearing forces that displace the stereocilia projecting from the tops of the hair cells.13

The conversion process functions as follows:
* Depolarization: When stereocilia are bent toward their longest side, ion channels open, allowing potassium ions to flow into the cell. This influx depolarizes the hair cell.1
* Neurotransmitter Release: The resulting depolarization triggers the release of neurotransmitters from the base of the hair cell.1
* Signal Transmission: These chemicals are absorbed by the nerve endings of the cochlear nerve, stimulating them to send electrical signals to the brain.14

Conversely, when stereocilia are deflected in the opposite direction, the ion channels close, hyperpolarizing the cell and inhibiting the signal. This complex mechanism allows the ear to translate physical sound energy into the neural information perceived as sound.13