Acoustics and Biomechanics

The questions we address include: 

  • How are sounds and vibrations coupled to the inner ear via the air- and bone-conduction pathways? 
  • How do the form and function of the eardrum and coupled ossicular chain limit the sounds that are audible in different vertebrate species? 
  • How do the normal and pathological pathways within the inner ear affect sound amplification and hearing function? 
  • How do the structures of the cochlea and middle ear determine the sensitivity to low- and high-frequency sounds in a variety of animals, including mice, gerbils, humans, and elephants?

Our researchers are focused on these questions. 

In the Eaton-Peabody Laboratories, we study the biomechanics of the middle ear and inner ear using a variety of techniques—including acoustical and mechanical measurements, imaging, physiology, and computational modeling—with the goal of improving human auditory diagnostics and therapeutics.

The tools we use to measure the microstructure and nanomotions of the ear include micro-CT scanning, 3D laser Doppler vibrometry, computer-aided laser holography, and optical coherence tomography. The motions we measure are produced by air-conducted sounds of different levels and frequencies as well as bone-conducted mechanical vibrations of the head and middle ear. Our results are evaluated against clinical measurements of the effects of different auditory pathologies, as well as computational models that range in complexity from simple circuit models to anatomically realistic finite-element models of the middle ear, cochlea, and the organ of Corti sensory epithelium within the cochlea.