brainstem auditory evoked potential


potential

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au·di·to·ry brain·stem re·sponse (ABR),

an electrophysiologic measure of auditory function using computer-averaged responses produced by the auditory nerve and the central auditory pathways principally in the brainstem to repetitive acoustic stimuli. ABR is also used to locate brainstem lesions and determine whether a hearing impairment is sensory or neural. Synonym(s): brainstem auditory evoked potential, brainstem evoked response

auditory brainstem response audiometry

A neurologic test of brainstem function in response to 70–90 dB auditory (click) stimuli transmitted by an acoustic transducer to headphones. The evoked waveform response is measured by surface electrodes placed at the vertex of the scalp and ear lobes. The signal amplitude is averaged and charted against the time, not unlike an EEG, with the waveform peaks being labelled I–VII.
Applications
Identification of retrocochlear pathology (e.g., acoustic neuroma or vestibular schwannoma), identification of coma patients at increased risk of dying, screening hearing in newborns.
Method
Electrodes are attached to the head to record electrical activity from the auditory and other regions of the brain.

brain·stem au·di·tor·y e·voked po·ten·tial

(brān'stem aw'di-tōr-ē ē-vōkt' pŏ-ten'shăl) Responses triggered by click stimuli, which are generated in the acoustic nerve and brainstem auditory pathways; recorded over the scalp.