A model of the hair cell-primary fiber complex

Abstract

The proposed model consists of a chain of three energy reservoirs through which energy from an infinite supply is fed to a modulator which in turn drives a firing mechanism. The modulator consists of a variable permeability p that depends on instantaneous basilar displacement a through: p = (a - AO)2 for a greater than AO, and p = O for a less than or equal to AO, where AO is a constant. The firing mechanism consists of a Poisson generator (process) whose average output rate is proportional to energy flow through the modulator, and a classical "leaky integrator" neuronal model driven by the Poisson generator. The model, containing three fixed and eight free parameters, was examined with respect to statistical properties of spontaneous activity, relation between overall firing rate and level of stimulation, various adaptation and recovery phenomena within time ranges from a few milliseconds to several seconds, period histograms for one- and two-tone (phase locked) stimulation, suppression of responses to one tone by subthreshold levels of another (phase locked) tone, and neural masking. Model behavior in general was satisfactory. Deficiencies in single-cycle histograms at medium and high levels, and insufficient onset peaking in PST histograms, were attributed to the malfunctioning of one particular segment of the model, and a possible remedy was suggested.