Realistic mechanical tuning in a micromechanical cochlear model.

Two assumptions were made in the formulation of a recent cochlear model [P.J. Kolston, J.

Nonlinear and active two-dimensional cochlear models: time-domain solution.

A numerical solution method for two-dimensional (2-D) cochlear models in the time domain is presented. The method has particularly been designed for models with a cochlear partition having nonlinear and active mechanical properties. The 2-D cochlear model equations are reformulated as an integral equation for the acceleration of the basilar membrane (BM).

Numerical methods for solving one-dimensional cochlear models in the time domain.

In this article, a robust numerical solution method for one-dimensional (1-D) cochlear models in the time domain is presented. The method has been designed particularly for models with a cochlear partition having nonlinear and active mechanical properties. The model equations are discretized with respect to the spatial variable by means of the principle of Galerkin to yield a system of ordinary differential equations in the time variable.

Cochlear power flux as an indicator of mechanical activity.

The question of whether one can conclude just from basilar membrane (BM) vibration data that the cochlea is an active mechanical system is addressed. To this end, a method is developed which computes the power flux through a channel cross section of a short-wave cochlear model from a given BM vibration pattern. The power flux is an important indicator of mechanical activity because a rise in this function corresponds to creation of mechanical energy.

Are active elements necessary in the basilar membrane impedance?

This article is motivated by the current hypothesis [Kim et al., Psychological, Physiological and Behavioural Studies in Hearing (Delft U. P.

Quantitative validation of cochlear models using the Liouville-Green approximation.

This article is devoted to the question of whether linear and passive models of the cochlea can mimic the recently observed sharply tuned data of basilar membrane vibration. The model equations are solved by means of an asymptotic approach, the Liouville-Green approximation, which is adequate for quantitative comparisons with experimental data. The conclusions are: (i) the older, mildly tuned basilar membrane responses can be matched very well by means of linear, passive models; (ii) the newer, sharply tuned data cannot be matched satisfactorily by linear, passive modelling.

Point-impedance characterization of the basilar membrane in a three-dimensional cochlea model.

In this paper we derive which impedance definition appropriately represents the basilar membrane in a simple three-dimensional model (de Boer's 'block model') of the cochlea. The starting point of our considerations is a system of parallel visco-elastic beams as characterization of the basilar membrane. It is possible to transform this representation into an impedance concept by observing that the membrane velocity is to a very good approximation distributed over the width as a centred half cosine function, independent of the pressure distribution.