Investigation of Vowel Duration in Stutterers and Nonstutterers

Some of researchers define stuttering as a disorder in timing feature between acoustic elements and interruption in successful and simultaneous programming of speech muscles movements for a word production. One of the temporal variable is vowel duration. Vowel duration is a feature that demonstrates between nature of phonation differences in stutterers and nonstutterers. The aim of this study was to study and compare the vowel duration in stutterers and nonstutterers.
The present study was descriptive and analytic and 22 stutterers and 22 nonstutterers participated and were asked to read a text that contains three contexts cv, cvc, cvcc and 6 vowels. Afterward, its summary and fluent speech from three contexts were selected and recorded by praat software and duration of vowels was computed via spectrogram.
Independent t test showed that stuttering (P=0.21) and age (P=0.061) did not have significant effect on vowel duration. However these values were higher in stutterers than nonstutterers.
This study showed that stuttering does not influence the vowel duration.