A system of linked resonators in cochlea

The cochlear partition is modelled with two parallel long elastic plates connected with a raw of springs. This system of linked resonators is studied by means of multi-degree-of-freedom systems theory. The normal frequencies of the cross section are calculated. It is found that if the partial eigenfrequency of isolated outer hair cell (spring) coincides with any of partial eigenfrequencies of any of two membranes – this frequency is also a normal frequency of the linked system, and the resonance at this frequency is especially sharp. It is concluded, that the slow changes of outer hair cell volume and intracellural pressure can be an effective tool for adjusting of the tuned system, while the fast oscillations remain to be simply forced mechanical vibration. The shifts in the resonance frequency, in magnitude and width of the tuning curve are found to be the results of slow motility of the outer hair cells.