title: A study of sound transmission in an abstract middle ear using physical and finite element models.
abstract: The classical picture of middle ear (ME) transmission has the tympanic membrane (TM) as a piston and the ME cavity as a vacuum. In reality, the TM moves in a complex multiphasic pattern and substantial pressure is radiated into the ME cavity by the motion of the TM. This study explores ME transmission with a simple model, using a tube terminated with a plastic membrane. Membrane motion was measured with a laser interferometer and pressure on both sides of the membrane with micro-sensors that could be positioned close to the membrane without disturbance. A finite element model of the system explored the experimental results. Both experimental and theoretical results show resonances that are in some cases primarily acoustical or mechanical and sometimes produced by coupled acousto-mechanics. The largest membrane motions were a result of the membrane's mechanical resonances. At these resonant frequencies, sound transmission through the system was larger with the membrane in place than it was when the membrane was absent.
authors.affiliation: Department of Civil Engineering, Materials and Fabrication, University of Malaga, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Gonzalez-Herrera
authors.affiliation: Department of Otolaryngology/Head and Neck Surgery and Department of Biomedical Engineering, Columbia University, New York, New York 10032, USA.
authors.forename: Elizabeth S
authors.initials: ES
authors.lastname: Olson
mesh_terms: D004432:Ear, Middle; D004867:Equipment Design; D020342:Finite Element Analysis; D007368:Interferometry; D008365:Manometry; D008567:Membranes, Artificial; D008953:Models, Anatomic; D008959:Models, Neurological; D009038:Motion; D011312:Pressure; D013016:Sound; D014432:Tympanic Membrane; D014732:Vibration
chemical_list: D008567:Membranes, Artificial