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M M Sondhi

Publications and source records attributed to M M Sondhi.

3 recordsLinked to original sources

Cochlear macromechanics: time domain solutions.

In this paper we report on a new method of solving a previous derived, two-dimensional model, integral equation for basilar membrane (BM) motion. The method uses a recursive algorithm for the solution of an initial-value problem in the time domain, combined with a fast Fourier transform (FFT) convolution in the space domain at each time step. Thus, the method capitalizes on the high speed and accuracy of the FFT yet allows the BM to have nonlinear mechanical properties. Using the new method we compute (linear) solutions for various choices of model parameters and compare the results to the experimental measurements of Rhode. [J. Acoust. Soc. Am. 49, 1218-1231 (1971)]. We also demonstrate the effect of including longitudinal stiffness along the BM and conclude that it is useful in matching the high-frequency slope as measured by Rhode.

Basilar Membrane

Method for computing motion in a two-dimensional cochlear model.

We describe an effective technique for computing the steady-state motion in a two-dimensional cochlear model. With the cochlear fluid assumed incompressible and inviscid, the problem reduces to solving Laplace's equation for a region with a yielding boundary (corresponding to the basilar membrane). From an integral equation representation of this solution, a pair of second-order differential equations is derived. The solution of these differential equations gives the velocity of the basilar membrane and hence other related quantities, e.g., displacement, pressure, driving-point impedance at the stapes. Higher-order approximations, as well as extensions to nonlinear membranes are discussed.

Acoustic Stimulation