Effects of frequency-shifted auditory feedback on voice F0 contours in syllables

Previous studies have shown that, during continuous vocalization, voice fundamental frequency (voice F0) is modified by frequency-shifted auditory feedback. In this study, the effects of frequency-shifted auditory feedback on voice F0 contours were determined for the first two syllables of the nonsense word [tatatas]. Results show that voice F0 is auditorily controlled with a long latency and responses are not interrupted by the onset and offset of phonation itself. Furthermore, after-effects were found in voice F0 in trials after the termination of the frequency shift, which indicates that the response persists for several seconds. It is argued that the purpose of the auditory-vocal system is not to control voice F0 precisely within single syllables, but rather on a supra-segmental level in the context of prosody.