An intonational analysis of disfluency patterns in chronically stuttered speech

While previous stuttering research has successfully revealed areas vulnerable to disfluency at the word level in stuttering, identifying the specific factors responsible for this instability has proved difficult; moreover, inconsistent results are complicated by a failure to control for the effects of phrasal prosody, which govern such word‐level factors as lexical stress. The present experiment tested the hypothesis that disfluencies in stuttering are directly proportional to the prominence‐level of a given production. Three stuttering subjects participated in an oral sentence‐reading task testing a variety of sentence types while manipulating intonational factors such as pitch accent type and location. It was anticipated that pitch‐accented syllables, representing a higher degree of stress in an intonation phrase than stressed but non‐pitch‐accented syllables, would be most prone to triggering disfluency, since they bear a greater level of prominence in the utterance. The results of the study confirmed the major hypothesis: in all of the comparisons between pitch‐accented and non‐pitch‐accented positions of stress, the former attracted the highest rate of disfluent speech productions. This supports the principal hypothesis that intonationally prominent domains, not simply lexically stressed syllables, are a better indicator of unstable positions in stuttered speech.