Share Email Print

Proceedings Paper

Motor noise in outer hair cells
Author(s): Kuni H. Iwasa; Xiao-Xia Dong
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Outer hair cells in the mammalian ear has a membrane based motor which directly converts electrical energy into mechanical energy. Such a motor is associated with the function of these cells in providing feedback to vibration in the inner ear. To obtain insights into the motor mechanism, we examined kinetics of charge transfer across the membrane in two different modes. One is to monitor charge transfer induced by changes in the membrane potential as an excess membrane capacitance. The other is to measure spontaneous flip-flops of charges across the membrane under voltage clamp condition as current noise. The noise spectrum of current was inverse Lorentzian and the capacitance was Lorentzian as theoretically expected. The characteristic frequency of the capacitance was about 10 kHz and that for current noise was about 30 kHz. This result is inconsistent with the prediction. The difference can be explained by a reciprocal effect of being a piezoelectric motor in that mechanical motion which is subjected to friction affects the frequency response.

Paper Details

Date Published: 30 April 2003
PDF: 10 pages
Proc. SPIE 5110, Fluctuations and Noise in Biological, Biophysical, and Biomedical Systems, (30 April 2003); doi: 10.1117/12.497616
Show Author Affiliations
Kuni H. Iwasa, National Institutes of Health (United States)
Xiao-Xia Dong, National Institutes of Health (United States)

Published in SPIE Proceedings Vol. 5110:
Fluctuations and Noise in Biological, Biophysical, and Biomedical Systems
Sergey M. Bezrukov; Hans Frauenfelder; Frank Moss, Editor(s)

© SPIE. Terms of Use
Back to Top