Professor Dolores Bozovic
Department of Physics
University of California Los Angeles

Mechanical sensitivity in hair cells of the inner ear

Abstract:

Inner ear hair cells perform the first step of auditory processing – they detect minute mechanical displacements due to the incoming sound and transduce them into electrical signals via opening of mechanically gated ion channels. These cells are operant in a viscous medium, but can nevertheless sustain oscillations, amplify incoming signals, and support spontaneous oscillations, indicating the presence of an underlying active process that must pump energy into the system. We will present latest results on the mechanisms of amplification, as well as means by which individual hair cells tune their responsiveness to stimulus. We have also been developing techniques to simultaneously track movements of multiple hair bundles. We applied this method to characterize spontaneous oscillations across the epithelium, to probe for any correlations in their motion or patterns in their frequency distribution.  And finally, we will discuss the effects of extracellular matrices as mechanical coupling elements, and their effects on phase-locking between hair cells.