Abstract:
The cochlear input impedance associated with the linear active component of cochlear mechanics is represented as an all-pole function of frequency. This allows the dynamics of the ear canal signal to be expressed in terms of the behavior of coupled damped harmonic oscillators. Spontaneous otoacoustic emissions correspond to negative damping and, consequently, unstable oscillations. The introduction of a compressive nonlinearity, which stabilizes the spontaneous emissions, gives an interesting and computationally simple model for investigating the response of the auditory periphery in the case where there are one or more spontaneous emissions. The model is used, in particular, for studying the behavior of the reflectance in the ear canal. The magnitude of the reflectance will normally be less than one due to the entrainment of the emissions.