A nonlinear electroelastic model of the auditory outer hair cell

Mechanically linear and electrically nonlinear constitutive relations for the auditory outer hair cell membrane (wall) are proposed. These relationships are derived on the basis of dual thermodynamic potentials. The active forces and active strains generated by the cell, important characteristics of the cellÕs behavior under physiological conditions, are associated with the mixed (piezoelectric) terms in the dual thermodynamic potentials. By using experimental information from four independent experiments, where the cell is loaded mechanically or electrically, the free parameters of the model are estimated. In addition, the model is extended to a composite representation of the cell membrane. In that representation, the outer layer is considered active (electroelastic) and the inner layer is considered passive (purely elastic). The layers are connected by elastic springs. The graphs for the elastic energy stored in the passive layer versus the cell wall potential are presented