AUDITORY-EVOKED BRAIN-STEM RESPONSES ELICITED BY MAXIMUM-LENGTH SEQUENCES IN NORMAL AND SENSORINEURAL EARS

Auditory brainstem responses (ABRs) were recorded using pseudo-random pulse trains called maximum-length sequences (MLSs), which allow high stimulus rates and simultaneous recording from both ears, and were com pared to ABRs obtained by conventional averaging. In normally hearing subjects, ABRs by MLSs produced the same waves as conventional ABRs, w ave latencies increased and amplitudes decreased. In normal as in sens orineural ears, MLS-ABR thresholds were similar to conventional ABR th resholds (except when binaural recordings were made) and were correlat ed with high-frequency audiometric thresholds. Binaural MLS-ABR record ings represent the individual response of each ear, as shown by record ings of monaurally deaf subjects.