Early pitch-shift response is active in both steady and dynamic voice pitch control

Abstract

When air conducted auditory feedback pitch is experimentally shifted upward or downward during steady phonation, voice pitch changes in response. The first pitch change is an automatic deflection opposite in direction to the feedback shift. It appears to help stabilize voice pitch by counteracting unintended changes. But what happens during an intended pitch change? If the purpose of the first pitch-shift response is to stabilize voice pitch around a fixed target, it should be suppressed during voluntary pitch changes. Alternatively, if the pitch-shift response is a general process of voice control it should be modified during intended pitch changes to bring production in line with the desired output. Auditory feedback pitch was shifted during steady pitch and upward glissando vocalizations by thirty trained singers. Contrary to the "steady-specific" hypothesis, pitch-shift responses occurred during dynamic pitch vocalizations. Responses were comparable in direction, peak time, and slope, but had significantly longer latency and smaller magnitude than responses elicited during steady note phonation. Results indicate that the early pitch-shift response is a general component of voice control that serves to automatically bring phonation pitch into agreement with an intended target, whether that target is constant or changing in time.