Frequency selectivity of the cochlea for formant peaks at high signal levels

The frequency selectivity for formant peaks in a synthetic continuous vowel was measured on a nonlinear model for motion of the basilar membrane. In spite of the fact that the model becomes more broadly tuned at high levels, the formant peaks in the model response become more sharply defined. This effect is caused by nonlinear suppression of the response to frequencies between adjacent formant peaks.