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Sex and environment shape cochlear sensitivity in human populations worldwide
Patricia Balaresque1, Sébastien Delmotte2, Franklin Delehelle3,4
1Centre de Recherche sur la Biodiversité et l'Environnement (CRBE) UMR5300, CNRS, Université de Toulouse, IRD, Université Paul Sabatier, 118 Route de Narbonne, Bâtiment 4R1, 31062, Toulouse, France. patricia.balaresque@univ-tlse3.fr.
Scientific Reports
|March 27, 2025
Summary
Environmental factors significantly impact cochlear sensitivity, influencing hearing
Area of Science:
- Evolutionary biology
- Auditory science
- Environmental health
Background:
- Hearing issues are a growing global concern, necessitating research beyond typical factors.
- The Acoustic Adaptation Hypothesis suggests environmental structures influence acoustic communication.
- The cochlea's role in sound processing makes it crucial for understanding environmental impacts on hearing.
Purpose of the Study:
- To investigate how environmental factors shape cochlear sensitivity.
- To evaluate the influence of endogenous and exogenous factors on auditory processes.
- To analyze the impact of diverse global environments on cochlear function.
Main Methods:
- Collected Transient-Evoked Otoacoustic Emissions (TEOAE) data from 448 healthy individuals across 13 global populations.
- Assessed cochlear sensitivity by measuring TEOAE profiles, focusing on amplitude and frequency spectrum.
- Analyzed six acoustic metrics derived from TEOAEs to characterize cochlear responses.
Main Results:
- Cochlear sensitivity amplitude is influenced by sex and environment, with environment showing a larger effect (up to 3.6 dB).
- Age and ear side also affect amplitude, but to a lesser extent.
- The frequency spectrum of cochlear sensitivity is exclusively determined by exogenous factors, with environment (altitude, urban/rural) being most significant.
Conclusions:
- Environmental factors, particularly altitude and setting (urban/rural), play a critical role in shaping cochlear sensitivity.
- Findings challenge the assumption that only biological factors influence auditory processes.
- Future auditory research must integrate both biological and environmental considerations.
Keywords:
Auditory processesCochlear sensitivityEnvironmentHuman populationsSexTransient-Evoked Oto-Acoustic Emission (TEOAE)VariabilityMore Related Videos
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