Work

Normal Hearing Sensitivity at Low to Middle Frequencies with ∼25% Prestin

Year: 2011

Type: conference-paper

Abstract: Two mechanisms have been proposed for outer hair cell (OHC)‐mediated amplification in the mammalian cochlea: hair‐bundle motility and somatic, prestin‐based, motility. In cochlear mechanical modeling, different amounts of OHC‐motor activity should provide different degrees of feedback efficiency and gain of the amplifier at resonant frequencies. We created two novel knock‐in prestin mice with reduced quantities (∼25% and 50%) of prestin. OHCs from these mice exhibited length, non‐linear capacitance (NLC) and electromotility values intermediate between wild‐type and prestin knock‐out mice. Surprisingly, hearing sensitivity up to 22 kHz of knock‐in and wild‐type mice are similar, so ∼25% prestin is sufficient for normal hearing at these frequencies. In these mice in the mentioned frequency range, OHC NLC and electromotility do not correlate with in vivo gain of the cochlear amplifier as predicted by the feedback model of the OHC motor.

Source: AIP conference proceedings

DOI: 10.1063/1.3658085