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Evaluation of Planar-Cell-Polarity Phenotypes in Ciliopathy Mouse Mutant Cochlea
Published on: February 21, 2016
Inverted direction of wave propagation (IDWP) in the cochlea
Egbert de Boer1, Jiefu Zheng, Edward Porsov
1Academic Medical Center, University of Amsterdam, Room D2-225/226, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
The Journal of the Acoustical Society of America
|March 19, 2008
Summary
New research on guinea pig basilar membrane (BM) wave propagation reveals that distortion product waves can travel forward, challenging the classical view. This "inverted direction of wave propagation" extends beyond classical theory predictions.
Area of Science:
- Auditory Neuroscience
- Bioacoustics
- Mechanics of Hearing
Background:
- The classical model of wave propagation along the basilar membrane (BM) posits bidirectional travel with identical properties.
- Recent experimental findings challenge this established view, suggesting alternative wave behaviors.
Purpose of the Study:
- To investigate wave propagation characteristics on the guinea pig basilar membrane (BM).
- To experimentally verify and characterize the phenomenon of "inverted direction of wave propagation".
Main Methods:
- Measurements of basilar membrane (BM) velocity in guinea pigs.
- Generation of distortion products (DPs) using two primary tones below the characteristic frequency.
- Recording DP phase as a function of DP frequency to analyze wave direction.
Main Results:
- Distortion product (DP) waves were observed traveling in both forward and reverse directions along the BM.
- The region exhibiting forward wave propagation was found to be more extensive than predicted by classical theory.
- These findings support recent experimental evidence on anomalous wave propagation.
Conclusions:
- The study confirms "inverted direction of wave propagation" on the basilar membrane.
- Experimental data align with theoretical predictions for a classical cochlear model, but highlight discrepancies in wave propagation extent.
- The findings necessitate a re-evaluation of classical wave propagation theories in the auditory system.
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