PURPOSE: To compare utterance duration of fluent speech of adults with different degrees of stuttering on a phrase repetition task. METHODS: Six adult stutterers, with severity degrees varying from mild to severe, were matched to individuals with no communication problems. The corpus was constituted by the words "horse", "popcorn" and "carpet" introduced into the vehicle-phrase "I say......quietly". Each phrase was uttered by the researcher and repeated aloud three times by the participants. The speech sample was recorded on a computer, and phrases containing disfluencies were rejected. After that, measurements of the acoustic duration of each sample were carried out using the software Praat 4.3. The phrases were divided into segments delimited by two consecutive voice onsets. Data were tabulated and statistically analyzed using t-test and Analysis of Variance (ANOVA). RESULTS: Stutterers took longer to produce all the units analyzed, except for the unit [ib]. The comparison among different stuttering severities showed that mild and moderate stutterers had similar duration measures, which was significantly different from severe stutterers. CONCLUSION: The analysis of acoustic duration parameters of units delimited by consecutive voice onsets demonstrated that stutterers differed from non-stutterers; moreover, these measures were able to differentiate among stuttering severity degrees.
Articulation disorders; Speech disorders; Stuttering; Speech acoustics; Speech production measurement; Sound spectrography
