Parameter estimation for the ABR source derivation

On the auditory brainstem response (ABR) intensity-latency curve, a critical point between linearity and nonlinearity seems to be approximately 50 dB HL. Above the critical point, the curve showed nonlinearity clearly, and it showed significant saturation at 80 dB HL. The normal and anesthesia ABR showed the same tendency. In the dynamic characteristic of the whole ABR, the vector length increased at sound levels over 50 dB HL. The anesthesia ABR showed strong dependence on consciousness level; the length gradually increased as the anesthesia progressed. In the ABR transfer function model, novel parameters were obtained for the proportional position control, differential action, and the first-order lag.<>