Mechanical Problems in Human Hearing

Abstract

For the description of the normal hearing process mechanical models are appropriate and distinct pathological situations can be simulated by changing specific parameters. Nonlinear behavior is found due to nonlinear constitutive equations of the ear drum, the ligaments and the coupling between implant and ossicles as well as due to active processes in the inner ear. Based on multibody system approach models of natural middle ears and reconstructed ears with active implants have been established including some rough assumptions of the nonlinear behavior. To study the dynamic behavior frequency domain methods and time integration has been used. A high risk of damaging the hearing organ of the inner ear is given for loud sound events especially in transient cases. Some measurements in the clinical practice are based on nonlinear effects to detect pathological situations. With simulated multifrequency tympanometry the effect of incudo-stapedial separation on umbo motion is shown. For actively driven implants the effect of different working conditions of the middle ear structure on sound transfer due to prestress in the coupling region has been simulated.

Pure-tone auditory threshold in school children

“…The mastoid cavity will be decoupled more and more depending on the tube size of the antrum mastoideum. The influence on the transfer function of the middle ear was correlated with the mastoid volume in simulations with a middle ear model [6,7]. For frequencies below 1 kHz, the simulations confirmed a reduced sensitivity up to 12 dB for small mastoid volumes compared with adult cavities.…”

Basilar Membrane and Tectorial Membrane Stiffness in the CBA/CaJ Mouse

“…The past decade has brought remarkable advances in the understanding of the micromechanics of the auditory system and its components (Barral and Martin 2011;Brownell et al 2011;Cheatham and Dallos 2000;Dong and Olson 2009;Eiber 2008;Elliott et al 2007Elliott et al , 2011Eze and Olson 2011;Fettiplace 2006;Fisher et al 2012;Gao et al 2013;Gavara and Chadwick 2009;Gavara et al 2011;Gu et al 2008;He et al 2008;Hemila et al 2010;Hong and Freeman 2006;Jacob et al 2009;Kapadia and Lutman 2000;Kitani et al 2011;Kolston 2000;Grosh 2011, Meaud andGrosh 2010;Naidu and Mountain 2007;Nam and Fettiplace 2012;Ren and Nuttall 2000;Rhode 2007;Santos-Sacchi 2008;Van Dijk et al 2011;Zhang et al 2007;Zheng et al 2007). Quantitative descriptions of basilar membrane motion patterns are available for the base and the apex of the mammalian cochlea (e.g., Olson et al 2012;Robles and Ruggero 2001).…”