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Dissection of the Auditory Bulla in Postnatal Mice: Isolation of the Middle Ear Bones and Histological Analysis
Published on: January 4, 2017
Missing links in some curious auditory phenomena: a tale from the middle ear
Michelle S Carpenter1, Anthony T Cacace, Marty J Mahoney
1Department of Communication Sciences and Disorders, Wayne State University, Detroit, MI, USA.
Journal of the American Academy of Audiology
|February 23, 2012
Summary
Broadband middle ear power reflectance (BMEPR) varies significantly with age, gender, and ear. These findings suggest middle ear transmission characteristics play a role in auditory function, impacting test development and interpretation.
Area of Science:
- Audiology
- Otoacoustic Emissions
- Middle Ear Physiology
Background:
- Broadband middle ear power reflectance (BMEPR) is an advanced, noninvasive electroacoustic measure for high-resolution middle ear assessment.
- Applicable across all ages, BMEPR is rapid to perform, but its clinical significance requires further investigation.
Purpose of the Study:
- To investigate the influence of age, gender, ear, and frequency on BMEPR in healthy adults.
- To determine if these factors necessitate adjustments in BMEPR test development.
- To explore implications for inner ear function and reconcile findings with existing literature.
Main Methods:
- A prospective, cross-sectional study analyzed BMEPR in 56 healthy adults (18-25 yrs and 50-65 yrs).
- Audiometry assessed for air-bone gaps; BMEPR was measured using a calibrated commercial system.
- A four-way repeated measures ANOVA examined effects of age group, gender, ear, and frequency (258-5040 Hz).
Main Results:
- Frequency significantly impacted BMEPR.
- Interactions were observed between gender and ear, gender and frequency, and age, gender, and ear.
- Younger females exhibited lowest reflectance in right ears; older females showed higher reflectance in right ears.
Conclusions:
- BMEPR variations align with known differences in hearing sensitivity and otoacoustic emissions across age, gender, and ear.
- These findings suggest middle ear transmission properties contribute to auditory function, alongside previously considered inner ear mechanisms.
- BMEPR data may refine our understanding of auditory physiology and inform future research applications.
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