Figure 4.

Modeling of electrically evoked hair-bundle movements. Stimulation at 1 Hz (Top) accelerated bundle oscillation during the negative phase of stimulation and arrested movement during the positive phase. Excitation with a 30-Hz current (Middle) mimicked the intermediate regime of bundle responsiveness, with complex but phase-locked bundle movements. The modeled response to 100-Hz stimulation (Bottom) displays phase-locking, with movements of a polarity opposite that of stimulation. The three records correspond to those for the same stimulus frequencies in Fig. 1A. Except for the frequency and amplitude of stimulation, the values of all parameters in the model were identical in the three simulations. The uppermost time calibration refers to the top record and the second calibration to both subsequent records; the distance and current calibrations apply to all three records.