Micromechanical Models for the Brownian Motion of Hair Cell Stereocilia

Brownian motion of the hairs (stereocilia) of amphibian hair cells has been shown in experiments to be in the range of some nm. Our models of the Brownian motion of coupled harmonic oscillators with mechanical properties of stereocilia lead to similar displacements. Computer simulations show that stochastic fluctuations enhance the encoding of low level acoustic signals. Stochastic resonance lowers the detection threshold of auditory signals to amplitudes one order of magnitude lower than that of the Brownian motion.