Nonlinear effects in human ear stimulated with sound and implant simultaneously

PRELUDIUM 21

Funding Organization: National Science Centre

Project title: Nonlinear effects in human ear stimulated with sound and implant simultaneously

Agreement number: UMO-2022/45/N/ST8/02447

Project implementation period: 02.02.2023 - 01.10.2025

Principal Investigator: mgr inż. Robert Filip Zabłotni

Project value: 140 000,00 PLN

Funds granted for Lublin University of Technology: 140 000,00 PLN

Abstract: The human ear is one of the smallest biomechanical systems. Mechanical models are used to analyze the dynamics of the human ear and are an indispensable part of mechanical engineering. Designing models of both lumped mass and the finite element method helps to better understand many phenomena, including vibrations of the auditory ossicles. For the FEM analysis of the middle ear, it is necessary to know the Young's Modulus, density and Poisson's ratio of individual elements, i.e. the ear bones, ligaments and tendons. For analysis using lumped mass models, it is necessary to know, among others, stiffness and damping coefficients. The aim of the project is to find the relationship between the excitation with sound of the tympanic membrane and the implant with help of the Finite Element Method modelling and Lumped Parameter model of the middle ear. Moreover it is also essential to study the dynamics of the middle ear, in particular the vibrations of the stapes. The novelty of this model will be its complex geometry obtained by micro-CT scanning the actual ossicles and research on double excitation in the human middle ear. After simulating and verifying the correctness of the intact ear model, an active implant will be attached to the long proces of the incus. There will be two models: Finite Elements Method model and Lumped Parameter Model. On the model with the implant, simulations will be performed in which the exciting forces will be applied to the tympanic membrane, just like in the intact ear, and to the implant. In this way, the nonlinear behavior of the system under the double excitation will be investigated. One of the most important results is whether in the human ear, stimulation with an implant and sound reaching the eardrum interferes with hearing. The result of the research may be appropriate parameters assigned to the implant, which will be able to correct the disturbance resulting from the double excitation. Another expected research result is the discovery of non-linear behavior in the implanted middle ear.