Analog and zero phase-shift digital filtering of the auditory brain stem response waveform.
Auditory brain stem response waveforms, derived from normal ears, were analyzed with a computer-based digital filtering program as a means of systematically evaluating the effects of phase-shift distortion. Off-line analysis involved the stimulated responses of a Butterworth-type filter at five high-pass and four low-pass frequencies, three filter slopes, and standard versus zero phase-shifting. Phase-shift, as seen with analog filters, proved to be a major cause of waveform distortion including significant latency and amplitude changes. A discussion on the need and use of digital filtering as well as suggested analog filter parameter settings is included.
D000328:Adult; D001933:Brain Stem / Q000502:physiology*; D003201:Computers; D004594:Electrophysiology / Q000379:methods*; D005072:Evoked Potentials, Auditory; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged