A micromechanical model for fast cochlear amplification with slow outer hair cells

Timothy K. Lu, Serhii Zhak, Peter Dallos, Rahul Sarpeshkar*

*Corresponding author for this work

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Scopus citations

Abstract

Recent experimental evidence has demonstrated that somatic outer hair cell (OHC) motility is important for amplification in the mammalian cochlea [1,2]. However, under the ‘somatic electromotility’ theory, the transmembrane potential that is responsible for driving the somatic OHC force is subject to low-pass filtering by the electrical RC time constant of the OHC membrane [3]. Numerous mechanisms have been proposed to compensate for the attenuation of the membrane potential by the low membrane time constant at high frequencies [3,4-10]. We present a micromechanical model derived from an engineering-based analysis of cochlear mechanics and experimental data. Our model does not require novel compensatory mechanisms and demonstrates that adequate OHC gain with negative feedback significantly extends closed-loop system bandwidth and increases resonant gain. The OHC gain-bandwidth product, not just bandwidth, determines if high-frequency amplification is possible. Thus, fast cochlear amplification is possible with slow OHCs simply due to in situ feedback dynamics, though our model does not preclude other compensatory mechanisms.

Original languageEnglish (US)
Title of host publicationAuditory Mechanisms
Subtitle of host publicationProcesses and Models - Proceedings of the 9th International Symposium
EditorsAlfred L. Nuttall, Tianying Ren, Peter Gillespie, Karl Grosh, Egbert de Boer
PublisherWorld Scientific Publishing Co. Pte Ltd
Pages433-441
Number of pages9
ISBN (Electronic)9812568247, 9789812568243
StatePublished - 2005
Event9th International Mechanics of Hearing Workshop on Auditory Mechanisms: Processes and Models, MoH 2005 - Portland, United States
Duration: Jul 23 2005Jul 28 2005

Publication series

NameAuditory Mechanisms: Processes and Models - Proceedings of the 9th International Symposium

Conference

Conference9th International Mechanics of Hearing Workshop on Auditory Mechanisms: Processes and Models, MoH 2005
Country/TerritoryUnited States
CityPortland
Period7/23/057/28/05

ASJC Scopus subject areas

  • Biotechnology
  • Biomedical Engineering

Fingerprint

Dive into the research topics of 'A micromechanical model for fast cochlear amplification with slow outer hair cells'. Together they form a unique fingerprint.

Cite this