Auditory evoked responses (AER) typically include Auditory Evoked Potentials (AEPs) and Otoacoustic Emissions (OAEs).
AEPs are electrical potentials, with amplitudes ranging from nanovolts (nV) to several microvolts (μV, uV), recorded from a specific part of the nervous system, particularly the brain, in humans or animals – elicited by presentation of a stimulus or multiple stimuli.
OAEs are very faint sounds, in the 0-20 dB SPL range, recorded from the occluded ear canal. They may occur without stimulation (Spontaneous OAE, SOAE), and in response to a transient stimulus like click, chirp, or tone burst (Transient OAE, TEOAE), and in response to simultaneously presented pure tones of different frequencies (Distortion Product OAE, DPOAE).
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