Autocorrelation models of pitch perception: In memory of ray meddis

Abstract

About 60 years ago, Licklider (1951, Experientia) described a qualitative model of autocorrelation that appeared to explain complex pitch perception. However, it was almost 40 years later before, Slaney and Lyon (1990, ICAASP) and Meddis and Hewitt (1991, JASA) incorporated autocorrelation into computational auditory models to test Licklider’s model of pitch perception. The Meddis and Hewitt frontend combined a level-dependent gammatone filterbank with Meddis’ (1986, JASA) inner hair-cell model. The “autocorrelograms” it produced revealed the temporal regularity of simulated auditory-nerve interspike intervals that occur in response to complex stimuli. The model was/is remarkably successful in accounting for a large set of complex pitch perception data. The model emphasizes the temporal structure of the neural information produced by a complex sound, in contrast to models that use a simple spectral representation of the resolved harmonics of a complex sound. Today, those who model complex pitch perception either use an autocorrelation-like approach or argue why such an approach does not work. The Meddis-Hewitt model is almost always considered in these modeling efforts. This presentation will describe the Meddis-Hewitt model and discuss its lasting effect on the study of complex pitch perception. [Work supported by NIDCD and Facebook Reality Labs grants to WAY.]