Virtual pitch in a computational physiological model.

A computational model of nervous activity in the auditory nerve, cochlear nucleus, and inferior colliculus is presented and evaluated in terms of its ability to simulate psychophysically-measured pitch perception. The model has a similar architecture to previous autocorrelation models except that the mathematical operations of autocorrelation are replaced by the combined action of thousands of physiologically plausible neuronal components. The evaluation employs pitch stimuli including complex tones with a missing fundamental frequency, tones with alternating phase, inharmonic tones with equally spaced frequencies and iterated rippled noise. Particular attention is paid to differences in response to resolved and unresolved component harmonics. The results indicate that the model is able to simulate qualitatively the related pitch-perceptions. This physiological model is similar in many respects to autocorrelation models of pitch and the success of the evaluations suggests that autocorrelation models may, after all, be physiologically plausible.