Interaction of stimulus parameters on the auditory brain stem response: a normal variant

The purpose of this investigation was to further define the effect that stimulus parameters of phase, intensity, and rate have in significantly reducing the wave V amplitude. Two separate experiments were conducted to determine whether an interactive effect exists and how robust the effect was on wave V. Results revealed that wave V amplitude was reduced to less than half the absolute amplitude of the wave IV-V complex in 9 of the 39 subjects. The phenomenon was dependent upon stimulus parameters of rarefaction phase, high intensity, and low repetition rate. Conversely, the phenomenon was independent of cochlear integrity, sex, and test equipment. The implications to diagnostic interpretation during routine auditory brain stem response testing are discussed.