Otoacoustic emissions arise from

OTOACOUSTIC EMISSIONS (OAEs) They are low-intensity sounds produced by outer hair cells of a normal cochlea and can be elicited by a very sensitive microphone placed in the external ear canal and analyzed by a computer. Sound produced by outer hair cells travels in a reverse direction: outer hair cells - basilar membrane - perilymph - oval window - ossicles - tympanic membrane - ear canal. OAEs are present when outer hair cells are healthy and are absent when they are damaged and thus help to test the function of cochlea. They do not disappear in VIIIth nerve pathology as cochlear hair cells are normal. Ref:-Dhingra; pg num:-27