sound emanating from the ear that can be recorded from minute microphones placed in the external auditory canal and is thought to be produced by the outer hair cells in the cochlea. Otoacoustic emissions occur spontaneously and can be evoked by acoustic stimuli; they are more prominent in women than in men and are particularly robust in infants. Indicative of the integrity of the auditory hair cells, they are measured to screen newborns for hearing impairment.