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Auditory nonlinearities: the role of cochlear hydromechanics
Hearing Research
|January 1, 1986
Summary
Nonlinearities in cochlear models explain auditory perception. These include harmonic distortion and envelope detection, with evidence supporting the latter in real ears.
Area of Science:
- Auditory Neuroscience
- Bioacoustics
- Fluid Mechanics
Background:
- Nonlinearities of hydromechanical origin were first observed in cochlear models.
- Two types of nonlinearities were identified: amplitude-dependent eddies causing harmonic distortion and asymmetrical displacements leading to envelope detection.
Purpose of the Study:
- To review evidence for hydromechanical nonlinearities in the cochlea.
- To assess the compatibility of observed nonlinearities with physiological experiments.
Main Methods:
- Review of historical and contemporary research on cochlear models.
- Comparison of theoretical findings with experimental data from physiological studies on ears.
Main Results:
- Type 1 nonlinearities (eddies, harmonic distortion) have circumstantial evidence.
- Type 2 nonlinearities (asymmetrical displacements, envelope detection) show compatibility with physiological experiments.
Conclusions:
- Hydromechanical nonlinearities play a role in cochlear function.
- Type 2 nonlinearities are particularly well-supported by physiological data, suggesting their relevance in actual auditory processing.
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