Document Type : Original Articles
Authors
1 Lecturer, Academic Member, Department of Speech Therapy, School of Rehabilitation, Tabriz University of Medical Sciences, Tabriz, Iran
2 PhD student, Cognitive Science, Academic Member, Department of Speech Therapy, School of Rehabilitation, Tabriz University of Medical Sciences, Tabriz, Iran
3 Lecturer, Department of Audiology, School of Rehabilitation, Tabriz University of Medical Sciences, Tabriz, Iran
4 PhD Student, Cognitive Neuroscience, Tabriz University of Medical Sciences, Tabriz, Iran
5 BSc, Department of Speech Therapy, School of Rehabilitation, Tabriz University of Medical Sciences, Tabriz, Iran
Abstract
Introduction: Voice onset time has been known to be the most reliable acoustic cue in differentiating voiced and voiceless stops. It can also be used in describing or categorizing various developmental, neuromotor and/or linguistic disorders. Values of voice onset time have been determined for many languages, and in the present study, voice onset time values were investigated for Persian language (Standard dialect).Materials and Methods: In this study, 44 healthy subjects, who were selected through convenient sampling method, produced each of 42 monosyllabic words twice. All stimuli contained 7 Persian stops in the initial position. Using Praat software, the voice onset time values were calculated in milliseconds according to waveform and wideband spectrograms. Vowel effect, sex differences, and the effect of place of articulation on VOT were analyzed.Results: No significant difference was found for the voice onset times obtained from male and female Persian speakers (P > 0.050). However, vowel and place of articulation had a significant effect on the voice onset times (P < 0.001). The mean of voice onset time values for /b/, /p/, /d/, /t/, /g/, /k/, /G/ consonants and for [c] and [ɟ] allophones, along with their standard deviations, were 12.41 (12.7), 78.27 (18.1), 89.44 (20.9), 16.63 (9.8), 100.73 (20), 30.34 (9.1), 23.98 (8.69), 33.6 (7.7) and 103.13 (18) ms respectively.Conclusion: It was revealed through this study that voice onset time values are the same for Persian-speaking men and women. However, like many other languages, back and high vowels and back place of articulation increased VOT values. Moreover, the results indicated that voiceless stops had long voicing lags and were aspirated in Persian language. On the other hand, voiced stops had positive VOT values and short voicing lags.Keywords: Voice onset time, Persian language, Consonant, Vowel