Effect of transducer fixation in the human middle ear on sound transfer

An ear is one of the smallest and the most important organs in a human body. Hearing loss becomes a significant problem for modern societies. Therefore, a non-linear model of the human middle ear is used to study effectiveness of a middle era implant. Special care is focused on the effect of floating mass transducer fixation on the ear system dynamics and sound transfer to the inner ear. A transducer fixation is realized by means of a coupler. Its characteristic plays the key role in stapes excitation. A numerical analysis for two variants of damping properties is performed, representing the intact and pathological ear stimulated by a low and strong external signal. A stiffness characteristic of the coupler can shift a main resonance region of the middle ear structure and cause polyharmonic and even chaotic motion of the stapes and the transducer. As a result, the conditions of regular and irregular vibrations of the stapes, near the primary resonance, are defined. Finally, practical remarks about how to avoid polyharmonic and irregular oscillations are proposed.

Automated summary

This study uses a non-linear model of the human middle ear to investigate the efficacy of a middle ear implant, with a focus on the impact of floating mass transducer fixation on ear system dynamics and sound transfer to the inner ear. The stiffness characteristic of the coupler plays a key role in stapes excitation, and can cause polyharmonic and chaotic motion of the stapes and the transducer. Recommendations are provided on how to avoid polyharmonic and irregular oscillations in the system.