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Published on: October 16, 2012
Quinine reduces the dynamic range of the human auditory system
E Berninger1, K K Karlsson, G Alván
1Department of Audiology, Karolinska Institute, Huddinge University Hospital, Sweden. Erik.Berninger@aud.hs.sll.se
Acta Oto-Laryngologica
|March 21, 1998
Summary
Quinine administration reversibly induces loudness recruitment in humans, serving as a model for cochlear hearing loss. This study quantified hearing changes, revealing specific impacts on auditory function.
Area of Science:
- Audiology
- Otoacoustic Emissions
- Pharmacology
Background:
- Cochlear hearing loss affects the auditory dynamic range.
- Quinine is a potential pharmacological agent to model hearing impairment.
- Understanding quinine's effects can elucidate hearing physiology.
Purpose of the Study:
- To evaluate and quantify quinine-induced changes in the human auditory dynamic range.
- To use quinine as a reversible model for cochlear hearing loss.
- To investigate the specific effects of quinine on auditory function.
Main Methods:
- Administered quinine hydrochloride to six otologically normal volunteers.
- Conducted refined hearing tests at various sound levels (threshold, moderate, high).
- Measured pure-tone thresholds, psychoacoustical click thresholds, and click-evoked otoacoustic emissions (CEOAEs).
Main Results:
- Quinine caused a maximal pure-tone threshold shift of 23 dB (1000-2000 Hz).
- Increased psychoacoustical click and CEOAE detection thresholds were observed.
- The stimulus-response function of CEOAEs indicated loudness recruitment.
Conclusions:
- Quinine is a valuable model for reversibly inducing complete loudness recruitment in humans.
- Quinine specifically affects certain aspects of hearing function.
- Further research into quinine's molecular mechanisms may advance hearing physiology understanding.
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