title: Distortion-Product Otoacoustic Emissions: Body Position Effects with Simultaneous Presentation of Tone Pairs.
abstract: This study examined the effect of three different body positions on distortion-product otoacoustic emission (DPOAE) amplitude and noise levels with multiple primary tone pairs simultaneously-presented to 36 normal-hearing female human adults. Other studies have demonstrated that the simultaneously presented tone pairs method shows clinical promise as a screener, but the sequential method remains in widespread clinical use. Postural changes have been suggested to have an effect not only on DPOAEs, but also transient-evoked OAEs and stimulus-frequency OAEs. DPOAE amplitude and noise levels were recorded in seated, supine, and side-lying positions to the following order of simultaneously-presented tone pairs relative to the f2 frequencies: 1187, 2375, and 4812 Hz; 1500, 3000, and 6062 Hz; and 1875, 3812, and 7625 Hz. No DPOAE could be detected reliably at 7625 Hz as result of poor signal-to-noise ratio. For remaining DPOAEs, statistical analyses revealed that amplitudes were not significantly different among the three body positions. However, at 1500 Hz and below, body position did have a statistically significant effect on noise levels though they are likely clinically negligible. Except at 7625 Hz, results suggest that DPOAEs recorded using a simultaneously presented tone pairs appear to be comparably recorded regardless of an individual's body position.
authors.affiliation: Department of Audiology and Speech Pathology, University of Arkansas at Little Rock, University of Arkansas for Medical Sciences , Little Rock, Arkansas.
authors.forename: Samuel R
authors.initials: SR
authors.lastname: Atcherson
authors.affiliation: Department of Communication Disorders, University of South Dakota , Vermillion, South Dakota, USA.
authors.forename: Amy
authors.initials: A
authors.lastname: Mattheis
keywords: body position; distortion-product otoacoustic emissions; multiple-tone pair stimuli; simultaneous