Otoacoustic emissions (OAEs) are sounds generated by vibrations of the hair cells in the cochlea of the inner ear. OAE testing utilizes a tiny probe fitted with a microphone and speaker that is used to stimulate the cochlea and measure its response. Individuals with normal hearing will produce emissions; when a hearing loss exceeds 25-30 decibels, no sound will be produced. This test helps determine whether there is a blockage in the ear canal, excess fluid in the middle ear or damage to the hair cells of the cochlea. OAE testing is often included in newborn hearing screening programs.