Variability in the production of/s/by adults who do and do not stutter

Speech produced by typically developing adults at their habitual speech rate is characterized by low utterance-to-utterance variability. Higher production variability has been hypothesized to underlie the occurrence of stutter-like disfluencies among individuals who stutter. Adults who stutter (AWS) have been found to have higher articulatory variability when producing sentences, nonwords and even single phonemes relative to fluent controls. Prior research also showed that movement variability has the potential to differentiate children who will recover from stuttering and the ones who will persist. However, it’s challenging to measure articulatory movement since it requires specialized instruments. Few studies measured variability acoustically. This study collects acoustic signals remotely and explores whether a group difference would also emerge in acoustic variability in producing a single phoneme/s/. If the measure is sensitive enough, the method can be adopted more widely. Nine AWS and Nine matched control produced 180 instances of the target sound/s/embedded within words and nonwords, which are further embedded in carrier phrases. The duration for/s/was significantly influenced by phonetic contexts. However, the current study did not find the spectral variability of/s/to be influenced by contexts nor did it differ by participant groups.