Juncture cues to disfluency

The paper describes properties of normal disfluent speech which help listeners to distinguish disfluent from fluent strings of speech. It focuses on juncture phenomena in cases where there is no clear silent pause at the interruption point. Recent attempts to define acoustically identifiable features of speech which can be seen as reliable indicators of disfluency have produced several suggestions. But studies of silent pause, (pre-)pausal lengthening, glottalisation and measurements of F ₀ have all failed to provide any reliable means of distinguishing fluent from disfluent continuations. The paper introduces into the discussion a phonological feature of speech which has been overlooked in previous work and which could prove to be a reliable indicator of disfluency, especially in mid-clause disfluencies where no pause is present at the interruption. In normal fluent continuous speech, words are not usually separated by silent pause into discrete units, but have their boundaries obscured or linked by processes like assimilation, liaison, elision and so on. The hypothesis examined by the study is that such juncture phenomena are blocked by disfluency. Evidence from perceptual experiments suggests that this phenomenon may be used by human listeners in early detection of disfluency