A mechanism for stimulated acoustic emissions in the cochlea

Stimulated acoustic emissions in the cochlea are explained in terms of its hydraulic properties. The mathematical model predicts that these ‘echoes’ are caused by reflections which result from a discontinuity in the resistive and reactive components of the impedance which occurs at resonance. This discontinuity is a direct result of the wavelength-dependent nature of the fluid inertance and occurs without the consideration of non-linearities. Calculations of the time delay of tone bursts to and from the places of reflection by determination of the group velocity agree with observations of the response latencies for the frequencies concerned.