Voice F0 responds to auditory feedback pitch shifts during both steady and dynamic vocal behaviors

Abstract

When trying to hold steady voice fundamental frequency (F0), subjects vocally oppose experimentally introduced small upward or downward shifts in auditory feedback pitch. These voice F0 responses have a latency of 100–150 ms, and occur despite efforts by subjects to ignore the feedback pitch shifts. The consistent and involuntary nature of these responses provides evidence of closed-loop fine control of voice F0. Studies of oculomotor and limb movement systems have revealed different control strategies for static versus dynamic behaviors. It is not clear whether the fine control voice F0 likewise differs. For this reason, a study was undertaken to determine if the voice F0 response to pitch-shifted auditory feedback was affected by task dynamics. Specifically, a comparison was made between responses to pitch shifts introduced during voice F0 hold and ramp tasks. Results indicate a similar role of the voice F0 response across both vocal behaviors, namely, to facilitate production of an intended target, be it static or dynamic.