title: Speech auditory brainstem response (speech ABR) characteristics depending on recording conditions, and hearing status: an experimental parametric study.
abstract: Speech elicited auditory brainstem responses (Speech ABR) have been shown to be an objective measurement of speech processing in the brainstem. Given the simultaneous stimulation and recording, and the similarities between the recording and the speech stimulus envelope, there is a great risk of artefactual recordings. This study sought to systematically investigate the source of artefactual contamination in Speech ABR response. In a first part, we measured the sound level thresholds over which artefactual responses were obtained, for different types of transducers and experimental setup parameters. A watermelon model was used to model the human head susceptibility to electromagnetic artefact. It was found that impedances between the electrodes had a great effect on electromagnetic susceptibility and that the most prominent artefact is due to the transducer's electromagnetic leakage. The only artefact-free condition was obtained with insert-earphones shielded in a Faraday cage linked to common ground. In a second part of the study, using the previously defined artefact-free condition, we recorded speech ABR in unilateral deaf subjects and bilateral normal hearing subjects. In an additional control condition, Speech ABR was recorded with the insert-earphones used to deliver the stimulation, unplugged from the ears, so that the subjects did not perceive the stimulus. No responses were obtained from the deaf ear of unilaterally hearing impaired subjects, nor in the insert-out-of-the-ear condition in all the subjects, showing that Speech ABR reflects the functioning of the auditory pathways.
authors.affiliation: Université de Lyon, Lyon F-69003, France.
authors.forename: Idrick
authors.initials: I
authors.lastname: Akhoun
authors.forename: Annie
authors.initials: A
authors.lastname: Moulin
authors.forename: Arnaud
authors.initials: A
authors.lastname: Jeanvoine
authors.forename: Mikael
authors.initials: M
authors.lastname: Ménard
authors.forename: François
authors.initials: F
authors.lastname: Buret
authors.forename: Christian
authors.initials: C
authors.lastname: Vollaire
authors.forename: Riccardo
authors.initials: R
authors.lastname: Scorretti
authors.forename: Evelyne
authors.initials: E
authors.lastname: Veuillet
authors.forename: Christian
authors.initials: C
authors.lastname: Berger-Vachon
authors.forename: Lionel
authors.initials: L
authors.lastname: Collet
authors.forename: Hung
authors.initials: H
authors.lastname: Thai-Van
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D000328:Adult; D000704:Analysis of Variance; D001300:Audiometry, Evoked Response / Q000379:methods; D001306:Auditory Pathways / Q000502:physiology; D001309:Auditory Threshold / Q000502:physiology*; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology*; D005260:Female; D046088:Hearing Loss, Unilateral / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011571:Psychoacoustics; D011930:Reaction Time / Q000502:physiology; D013060:Speech / Q000502:physiology*; D013067:Speech Perception / Q000502:physiology*; D055815:Young Adult