Active hair-bundle motility harnesses noise to operate near an optimum of mechanosensitivity.

ABSTRACT: The ear relies on nonlinear amplification to enhance its sensitivity and frequency selectivity to oscillatory mechanical stimuli. It has been suggested that this active process results from the operation of dynamical systems that operate in the vicinity of an oscillatory instability, a Hopf bifurcation. In the bullfrog's sacculus, a hair cell can display spontaneous oscillations of its mechanosensory hair bundle. The behavior of an oscillatory hair bundle resembles that of a critical oscillator. We present here a theoretical description of the effects of intrinsic noise on active hair-bundle motility. An oscillatory instability can result from the interplay between a region of negative stiffness in the bundle's force-displacement relation and the Ca(2+)-regulated activity of molecular moto

SUBMITTER: Nadrowski B 

PROVIDER: S-EPMC514456 | biostudies-literature | 2004 Aug

REPOSITORIES: biostudies-literature