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Hi all, We are very happy to announce Assoc. Prof. Sunil Puria (Department of Otolaryngology, Harvard Medical School and Massachusetts Eye and Ear) will be speaking on “Measurements of Cochlear amplification, compression and transduction”
at 2pm (UK time) on the 31st of August. The seminar will be held over MS Teams. Click
here to join the meeting Speaker bio Sunil Puria is Associate Professor in the Department of Otolaryngology, Harvard Medical School, and Amelia-Peabody Scientist at Massachusetts Eye and Ear. He studies the biomechanics of the middle ear and cochlea using imaging modalities
such as optical coherence tomography (OCT) and uCT and physiology using laser 3D Doppler vibrometers that are incorporated into finite element models. Abstract Throughout history, our understanding of cochlear amplification, compression and transduction mechanisms has gone through major changes. The ter Kuile model (1900) has been the standard for converting basilar membrane (BM) motion to hair
cell transduction. Bekesy (1947) formulated the travelling wave, but all based on passive mechanics in cadaver ears. Rhode (1971) changed all that when he showed in vivo compressive non-linearity of the BM. Brownell’s (1985) measurements indicated that the
site of the non-linearity and sensitive hearing are the beautifully arranged three rows outer hair cells (OHCs). Reticular lamina (RL) motion has recently been shown to move more than the BM. Our knowledge of cochlear organ-of-Corti mechanics is once again
undergoing another major rethinking. Much of this is being heralded by the advent of optical coherence tomography (OCT) which allows displacement measurements with Angstrom level resolution. Our measurements in the gerbil high-frequency basal region reveal
that the RL at OHC row 3 moves significantly more than at OHC row 1. This new discovery suggests that the RL’s mosaic structure is not stiff, but rather bends and/or stretches and questions the prevailing ter Kuile model for transduction. This has implications
for transduction in the human and mouse cochlea which we also measure using OCT. Timothy Beechey Hearing Sciences – Scottish Section, Mental Health and Clinical Neurosciences, School of Medicine University of Nottingham |