The auditory steady state evoked response (ASSR) is a brain response elicited by a continuous or steady state acoustic stimulus. ASSRs are evoked by modulated tonal stimuli and provide frequency – specific measures of hearing sensitivity across a wide rage of frequencies (250 to 8000 Hz). The primary clinical application for Auditory Steady-State Evoked Response is for detailed frequency-specific hearing assessment in babies. Since ASSR measures electrophysiological responses to sounds, it allows us to objectively assess how well a subject hears. This is especially useful in patients who are unable or unwilling to give reliable behavioral responses. ASSR can be reliably recorded in sleeping neonates and children.
They are evoked by frequency-specific tonal stimuli, can be detected objectively using statistical algorithms, have thresholds that are highly correlated with behavioral audiogram thresholds, and can be used to estimate the behavioral pure tone audiogram.  The estimated audiograms obtained from ASSR testing provide a basis for determining whether the child requires a cochlear implant or not