An oscillatory template pitch model

Abstract

Traditional approaches to explaining missing fundamental and pitch-shift phenomena have relied on either the fitting of harmonic templates to spectral information (generally assumed to correspond to a neural excitation pattern), or by performing an autocorrelation-based calculation on temporal information. In this paper, an alternative approach relying on the dynamics of phase-locking oscillators is proposed. Rather than applying some decoding procedure, such as spectral analysis or autocorrelation, a pitch estimate is given by the state (firing frequency) of an appropriately excited oscillator in a template structure operating on peripheral information. This approach is shown to reproduce many of the classical pitch shift-phenomena. In addition to a direct implementation in terms of phase-locking oscillators, a simplified model consisting of arrays of adaptive templates, operating directly on timing information, is also presented. This latter approach offers a straightforward way to tune the model in acc...