title: Effects of electrode placement on the auditory brainstem response using ear canal electrodes.
abstract: The effects of electrode placement on the latency and amplitude of the auditory brainstem response (ABR) were investigated in normal-hearing subjects. Ear canal (EC) electrodes were used in conjunction with surface electrodes to obtain ABRs. Three electrode combinations were evaluated: (1) vertex-EC-EC; (2) vertex-EC-neck; and (3) forehead-EC-neck. Absolute and interwave latencies and absolute and relative amplitudes were computed for Waves I, III, and V at 75 dB SL. Standard errors of measurement (SEmeas) revealed excellent test-retest reliability for latency (SEmeas = 0.06 ms) but only fair reliability for amplitude (SEmeas = 55 nv). No reliability differences were observed among the three electrode combinations. No significant latency or interwave latency differences were found among the three montages. No amplitude differences were found for Waves I and III among the montages. However, the Wave V amplitude was larger for the vertex-EC-EC and vertex-EC-neck montages than for the forehead-EC-neck montage. Because the vertex-EC-EC montage does not require additional electrodes on the contralateral neck, this montage is recommended.
authors.affiliation: Department of Communicative Disorders, California State University, Long Beach 90840.
authors.forename: R C
authors.initials: RC
authors.lastname: Beattie
authors.forename: L A
authors.initials: LA
authors.lastname: Lipp
mesh_terms: D000161:Acoustic Stimulation / Q000295:instrumentation* / Q000379:methods; D000328:Adult; D000818:Animals; D006224:Cricetinae; D004424:Ear Canal / Q000033:anatomy & histology / Q000502:physiology*; D004566:Electrodes; D004867:Equipment Design; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology*; D005260:Female; D006311:Hearing Disorders / Q000175:diagnosis / Q000503:physiopathology*; D006801:Humans; D008297:Male; D015203:Reproducibility of Results