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The speed limit of outer hair cell electromechanical activity

  • J. Santos-SacchiEmail author
Leitthema

Abstract

The outer hair cell of Corti’s organ provides mechanical feedback into the organ to boost auditory perception. The fidelity of voltage-dependent motility has been estimated to extend beyond 50 kHz, where its force generation is deemed a requirement for sensitive high-frequency mammalian hearing. Recent investigations have shown, however, that the frequency response is substantially more low pass at physiological membrane potentials where the kinetics of prestin impose their speed limit. Nevertheless, it is likely that the reduced magnitude of electromotility is sufficient to drive cochlear amplification at high frequencies.

Keywords

Organ of Corti Auditory perception Cochlea Membrane potentials Feedback 

Geschwindigkeitsbegrenzung der elektromechanischen Aktivität der äußeren Haarzellen

Zusammenfassung

Von der äußeren Haarzelle des Corti-Organs gibt es zur Verstärkung der Hörwahrnehmung eine mechanische Rückkopplung. Die Genauigkeit der spannungsabhängigen Motilität wurde auf über 50 kHz geschätzt, wobei ihre Krafterzeugung als Voraussetzung für das empfindliche Hochfrequenzhören der Säugetiere angesehen wird. Neuere Untersuchungen haben jedoch gezeigt, dass die Frequenzantwort bei physiologischen Membranpotenzialen, bei denen sich die Geschwindigkeitsgrenze der Kinetik von Prestin auswirkt, wesentlich niedriger ist. Es ist jedoch wahrscheinlich, dass das verringerte Ausmaß der Elektromotilität ausreicht, um die Cochleaverstärkung bei hohen Frequenzen zu steuern.

Schlüsselwörter

Corti-Organ Auditorische Wahrnehmung Cochlea Membranpotenziale Rückkopplung 

Notes

Acknowledgements

This work was supported by National Institutes of Health-National Institute on Deafness and Other Communication Disorders Grants R01 DC000273, R01 DC016318, and R01.

Compliance with ethical guidelines

Conflict of interest

J. Santos-Sacchi declares that he has no competing interests.

This article does not contain any studies with human participants or animals performed by any of the authors.

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Copyright information

© Springer Medizin Verlag GmbH, ein Teil von Springer Nature 2019

Authors and Affiliations

  1. 1.Surgery (Otolaryngology), Neuroscience, and Cellular and Molecular PhysiologyYale University School of MedicineNew HavenUSA

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