Efferent innervation and function

Efferent neurones inhibit outer hair cells to modulate cochlear sensitivity. Mechanosensory hair cells of the organ of Corti and vestibular end-organs transmit information regarding sound and body position and motion to the central nervous system by way of peripheral afferent neurons. In return, the central nervous system provides feedback and modulates the afferent stream of information through efferent neurons. This article focuses on auditory signaling. Efferent activity inhibits auditory endorgans. It explains the efferent innervation of the mammaliam cochlea, its development, and discusses the efferent neurotransmitters. It also deals with hair cell responses and efferent effects on cochlear output. Furthermore, it gives information about hair cell nicotininc receptors, giving insights from genetically modified mice. While good progress has been made in identifying the ionic channels that contribute to the hair cell's cholinergic response, a variety of questions remain for future study, these challenges are forming the basis for future research.