Macro and micro mechanical motion in the living mammalian cochlea

Nigel Cooper, University College London, London, UK

Hopeman 224

Basilar membrane (BM) vibrations introduce tonotopy, level dependent tuning, and frequency dependent nonlinearities into a signal processing scheme that is fundamental to mammalian hearing. How these vibrations gain such characteristics remains a mystery - after all, the BM is just a collagenous ribbon suspended in the fluid filled chambers of the inner ear. Recent applications of new measurement techniques, including spectral domain optical coherence tomography (SD-OCT), are starting to reveal how the hidden mechanics of the organ of Corti might ‘control’ the BM’s motion, and/or couple it to other important structures. This talk will summarise some recent findings made using the OCT technique, focusing on both the "macromechanics" and "micromechanics" of the system.