How do hair cells in the organ of Corti convert sound vibrations into nerve signals?

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Meissner's corpuscle; mechanoreception — Mechanoreception In human skin, specialized nerve endings known as Meissner's corpuscles (or tactile corpuscles) are sensitive to touch. They are one of several different types of mechanoreceptors found in human skin.

In the organ of Corti, hair cells convert sound vibrations into nerve impulses through a process of mechanical displacement and electrochemical signaling.1

When sound causes the basilar membrane to vibrate, shearing forces are created between the reticular lamina and the tectorial membrane. This movement bends the stereocilia located at the top of the hair cells.1

The conversion process functions as follows:
* Depolarization: When stereocilia bend toward their increasing length, ion channels open, allowing potassium ions to flow into the cell. This influx depolarizes the hair cell.1
* Hyperpolarization: When deflected in the opposite direction, these channels close, inhibiting or hyperpolarizing the cell.1
* Signal Transmission: Depolarization triggers the release of neurotransmitters from the base of the hair cell. These chemicals are absorbed by nerve fibers, which then transmit electrical signals along the cochlear nerve.1

This mechanism is sensitized by a steep electrical gradient, known as the endocochlear potential, maintained by the difference in ion content between the endolymph and perilymph.1