Theoretical dependence of cochlear fibre discharge rate versus intensity function on frequency: evidence for basilar membrane nonlinearity?

The suggestion that the frequency dependence of the slope of the cochlear fibre discharge rate vs. intensity function is evidence for a frequency-dependent basilar-membrane nonlinearity, is challenged by a demonstration that such frequency dependence of slope can be derived from a model of the cochlea which involves only linear filters and memoryless, frequency-independent nonlinearities. Some of the shortcomings of both models are briefly discussed. A third type of model, involving feedback, is tentatively proposed, which might more parsimoniously explain neurophysiological results.