Understanding the micromechanics of the cochlea

The cochlea converts the acoustic waveform at our ears into the neural signals that travel to our brain and allow us to hear. It has some remarkable mechanical properties, including an active mechanism that amplifies the amplitude of the wave that travels along the cochlea. It is known that this "cochlear amplifier" is powered by specialist outer hair cells, but the detailed way in which these cells interact mechanically with the other cells in the organ of Corti is not well understood.

Although theoretical models have been used for some time to try to understand this interaction, it has been impossible to validate these models, since there have been no measurements of the internal motion of the active organ of Corti. Recent animal measurements at several centers, using novel optical techniques, are now starting to reveal this motion for the first time. These measurements provide some excellent data on which to base new models of the micromechanics, the details of which could then be verified by further experiments.

This project will involve the development of a model of the micromechanics of the cochlea, involving the relative motion of the different parts of the organ of Corti, based on these recent measurements. It would mainly involve theoretical development and numerical simulation, although optimization techniques have recently been used to fit potential models to measured data from Stanford University