otoacoust

otoacoust refers to sounds generated from within the ear. These sounds are not consciously heard but can be measured by sensitive microphones placed in the ear canal. Otoacoustic emissions (OAEs) are the most common type of otoacoustics. They are thought to be produced by the vibrations of the outer hair cells in the cochlea, a structure in the inner ear responsible for hearing. As these hair cells move in response to incoming sound waves, they generate a faint echo that travels back out of the cochlea and through the middle ear to the ear canal.

The presence and characteristics of OAEs can provide valuable information about the health and function of the cochlea and outer hair cells. They are commonly used in audiology for hearing screening in newborns and infants, as they can detect hearing loss even before behavioral responses can be reliably assessed. OAE testing is non-invasive and relatively quick. Abnormal or absent OAEs can indicate a problem with the outer hair cells or conductive hearing loss in the middle ear. Different types of OAEs, such as transient-evoked otoacoustic emissions (TEOAEs) and distortion-product otoacoustic emissions (DPOAEs), are used to assess different aspects of cochlear function. The measurement of otoacoustic emissions is a significant advancement in the objective assessment of hearing.