Correlation study of two-channel recordings of the brain stem auditory evoked potential.

Two-channel recordings of the brain stem auditory evoked potential (BAEP), for example, forehead to ipsilateral mastoid and forehead to contralateral mastoid, presumably provide "views" of the generators from different, nearly orthogonal, directions. The two channels thus are expected to register somewhat different waveforms, as revealed by past research. Still, the absolute latencies of the peaks are expected to be strongly correlated between channels. To test this notion, correlation analyses were made of the latencies of positive and negative peaks of normal-appearing BAEPs. The results demonstrated the expected high correlations for brain stem components but less tight coupling between peaks of waves of more peripheral origins. The possible influence of residual noise also was considered. Implications of the findings for clinical and multichannel recording applications are discussed.