Auditory and vestibular systems display mechanical coupling of active, oscillating components. The strength and extent of this coupling varies across species and organs, depending on the specific task of each system. It is believed that this mechanical coupling is essential to achieve sufficient s ensitivity, frequency s electivity, and temporal resolution for reliable s ignal detection. These characteristics depend heavily on the ability of the active oscillators to synchronize with each other. It has previously been shown that spontaneous otoacoustic emissions may arise through a dynamical systems phenomenon known as frequency clustering, where active oscillators synchronize with those of similar characteristic frequency, forming several distinct clusters. In this work, we demonstrate that nonisochronous oscillators (those with amplitude-dependent characteristic frequencies) enhance the stability of these clusters, yielding larger, sharper spectral peaks. Further, we show that nonisochronicity enhances the ability of the system to detect weak signals. We propose that auditory and vestibular systems utilize nonisochronicity as a mechanism of facilitating synchronization among oscillating components to enhance signal detection.
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