Suppression of responses to pitch perturbations during Mandarin speech

Abstract

Previous research on the task dependency of voice fundamental frequency (F0) responses to pitch‐shifted feedback has shown them to be larger during speech than in a vowel task. The present study investigated how responses to pitch‐shift stimuli vary with the intonation of a speech utterance and the timing of the pitch shift stimuli. Mandarin speakers produced a four‐word phrase in which the F0 was held relatively steady and then either increased or was held steady on the final word. Pitch shift stimuli (100 cents, 200 ms) were presented 160, 240, or 340 ms after the onset of vocalization. F0 response magnitudes for the 340 ms onset condition were significantly smaller than in the 160 or 240 onset conditions when the F0 level on the final syllable was rising. When the F0 on the final syllable was held constant, there was no difference in response magnitudes between the three onset conditions. The decrease in response magnitude in the 340 ms, F0 rising condition, corresponding to approximately 660 ms before the final syllable, suggests vocal responses can be modulated both by the timing of stimulus presentation and the speech intonation pattern. Possible explanations for this finding will be discussed.