Examining the Effects of Anisotropy on Longitudinally Propagating Waves on Isolated Tectorial Membranes

Knowledge of the mechanical properties of the tectorial membrane (TM) would improve the understanding of TM function in hearing mechanics. In recent years, several groups have used measurements of wave propagation on isolated TMs to estimate the mechanical properties of the TM at acoustic frequencies. However, these studies have ignored the curvature, finite dimensions and anisotropy of the TM. In this study, optical images of an isolated wild-type basal TM segment in response to harmonic radial excitation are used to determine the amplitude and phase of the motion at acoustic frequencies. Wave propagation on the TM segment is modeled using a finite element model that takes into account the geometry, anisotropy and viscoelasticity of the TM. An automated least-square fitting algorithm is used to find material parameters of the TM. The resulting material properties are compared to previous estimates.