Effects of Supplemental Magnesium on Temporary Threshold Shift: Distortion Product Otoacoustic Emissions
Degree Granting Department
Richard A. Roberts, Ph.D. Chair
Harvey B. Abrams, Ph.D. Co-Chair
K. Paul Boyev, M.D. Co-Chair
Raymond Hurley, Ph.D.
temporary threshold shift, TTS, distortion product otoacoustic emissions, DPOAE, supplemental magnesium, noise induced hearing loss
Previous studies have shown that supplemental magnesium administered prior to exposure to noise has an alleviating effect on temporary threshold shift (TTS). These studies have only used audiometric thresholds to demonstrate changes in the auditory system. However, to help determine the effects on outer hair cells (OHCs), a more sensitive measure should be used. The purpose of this study was to determine if supplemental magnesium administration prior to noise exposure has a beneficial effect on acoustic overexposure using a double-blind research design. This was determined by measuring distortion product otoacoustic emissions (DPOAEs) to determine any changes in cochlear OHC function. DPOAE amplitude and signal-to-noise ratio (SNR) measurements were analyzed for two groups of twenty participants (an experimental group and a control group). The experimental group received 150 mg of magnesium gluconate one hour prior to noise exposure. The control group received a placebo pill that was identical in appearance to the magnesium pill. Following noise exposure, the greatest changes in DPOAE amplitude and SNR occurred for the frequencies that were one-half to one octave above the frequency of the stimuli used. The greatest changes in DPOAE measurements were present immediately post TTS-inducing stimulus, with only slight changes present after 30 minutes and no difference between 30 minutes and 60 minutes post-exposure. These results were the same for both groups. It was concluded that this dosage of supplemental magnesium had no apparent protective effect on DPOAEs following intense noise exposure.
Scholar Commons Citation
Leonard, Jenifer, "Effects of Supplemental Magnesium on Temporary Threshold Shift: Distortion Product Otoacoustic Emissions" (2003). USF Tampa Graduate Theses and Dissertations.