Clustering of cochlear oscillations in frequency plateaus as a tool to investigate SOAE generation

Spontonaeous otoacoustic emissions (SOAE) reflect the net effect of self-sustained activity in the cochlea, but do not directly provide information about the underlying mechanism and place of origin within the cochlea. The present study investigates if frequency plateaus as found in a linear array of coupled oscillators (OAM) [7] are also found in a transmission line model (TLM) which is able to generate realistic SOAEs [2] and if these frequency plateaus can be used to explain the formation of SOAEs. The simulations showed a clustering of oscillators along the simulated basilar membrane Both, the OAM and the TLM show traveling-wave like behavior along the oscillators coupled into one frequency plateau. While in the TLM roughness is required in order to produce SOAEs, no roughness is required to trigger frequency plateaus in the linear array of oscillators. The formation of frequency plateaus as a consequence of coupling between neighbored active oscillators might be the mechanism underlying SOAEs.