LAUSR

Nobel Laureate von Békésy first discovered travelling wave vibration of the basilar membrane (BM) in cochlea in1960, and thus the mysterious veil of passive phonoreceptive mechanism of human cochlea was unveiled. However, the interpretation of active phonoreceptive mechanism of human cochlea has been a major medical problem for mankind, which has received wide attention from scientists. The active mechanism can be reflected in structures and the lymph where a series of complex coupling nonlinear motion process is observed in the cochlea. Because the cochlea is small and complex, vibration data of the whole BM are not yet available from existing experiments. To address the problem, firstly, the motion equations of the organ of Corti (OHC) is established, and the circuit equations of the outer hair cells (OHCs) in the lymph and the relationship between the motion of the outer hair cells and the electrostatic force are derived. Then the active feedback force onto the BM is obtained. Finally, a analytical-numerical combination model of cochlea, where both macro structures and micro structures of cochlea are considered, is established. The model not only vividly depict the spatial helical body and biological materials of the cochlea, but also reflect the fluid-solid coupling nonlinear motion of cochlear structures in the electrical environment. Thus, the active process of cochlea is revealed.