VARIABILITY AND DURATION OF VOICE ONSET TIME AND PHONATION IN STUTTERING AND NONSTUTTERING ADULTS

Eighteen male stutterers and 16 male nonstutterers who were matched according to age and social status were required to speak the testwords /kakakas/, /tatatas/, and /papapas/ with stress on the middle syllable at two different speech rates. Duration of phonation, voice onset time, and coefficients of variation were computed and analyzed. It was shown that stutterers produced, even during nonstuttering periods under repetitive articulation, an enhanced variation of voice onset time and an increased variability for the duration of phonation associated with the production of the first syllable. Furthermore, this experiment did not confirm the often reported differences in voice onset time and vowel duration between stutterers and nonstutterers.