Auditory Brainstem Response (ABR)

ABR is the gold standard. ABR activity is a direct measurement of the neural response to sound that is generated along the auditory system from the level of the cochlea and through the VIII nerve and pontine-level of the brainstem and that correlates with behavioral hearing measures in the mid- to high-frequency region. The ABR is recorded using surface electrodes that are attached to the infant’s head. Click stimuli are presented through insert or muff-style earphones that are worn on both ears. ABR measurements are sensitive to neural auditory disorders (i.e., auditory neuropathy). Auditory neuropathy is a neural hearing loss that leaves cochlear (outer hair cell) function intact. ABR screening is less sensitive to outer ear debris than OAE screening, resulting in lower referral rates. This is the only method that tests the entire hearing pathway. 

Otoacoustic Emissions (OAE)

OAEs – either transient-evoked OAEs (TEOAEs) or distortion product OAEs (DPOAEs) – are measured using a sensitive probe microphone inserted into the infant’s ear canal. OAEs are a direct measure of outer hair cell and cochlear function in response to acoustic stimulation. They yield an indirect estimate of peripheral hearing sensitivity. OAEs are not sensitive to disorders central to the outer hair cells, such as auditory neuropathy. OAEs will be absent when there is outer or middle ear dysfunction or debris/blockage in the ear canal.