Contribution
Pitch discrimination of unresolved pure tones: a glance at the temporal pitch code
* Presenting author
Abstract:
While pitch perception for broadband sounds relies on a number of perceptual cues, resolved harmonics are assumed to be particularly important. Resolved harmonics (i.e., pure tones) provide both temporal and tonotopic place cues. Interestingly, it is still not clear to what extent human pitch perception of a pure tone relies on temporal versus place coding as a function of tone frequency. This question also has practical importance, particularly for “electric hearing” with cochlear implants (CIs). When increasing the stimulation pulse rate at a single electrode, CI listeners perceive increasing pitch only up to about 400 Hz. Here we ask if this so-called rate limit is CI-specific or also found in normal hearing. To that end, we measure pure-tone pitch thresholds with and without complex-tone maskers that are designed to selectively remove place but preserve temporal pitch cues, in a cohort of normal-hearing listeners. Confounding pitch cues are avoided by roving the masker pitch between intervals of a trial. Data collected so far for the low-frequency region show very high pitch sensitivity for conditions providing no place cues at all, according to established models of the auditory periphery, indicating exquisite temporal coding even for completely unresolved tones.