Description of Three Time-Domain Speech Features in Children with Down Syndrome: A Pilot Study

Background: The present pilot study aims at investigating the three features of time domain in speech in Persian-speaking children with Down syndrome. Methods: In this Cross sectional study, our sample consisted of two 3-8-year-old children (2 males) with Down syndrome (4.9 years old and standard deviation of 1.52). Inclusion criteria were children with Down syndrome, aged 3-8 years old, no neurological or motor disorders, sensory disorders and psychiatric disorders. The voice sample of the children was analyzed with Praat, and the phonetic features of the voice onset time, vowel duration time and closure duration time were evaluated and descriptive statistics were reported by the Statistical Package for Social Sciences version (SPSS, Inc., Chicago IL, USA; version 16). Results: we found that in /pa/, the mean of the voice onset time variable is (0.04±0.00) and in /ta/ the mean of the voice onset time variable is (0.04±0.00). Conclusion: According to the results of this study, it can be concluded that the speech time domain features in Persian-speaking children with Down syndrome were similar to these features in other languages, which could be due to problems with the tone and muscular strength in these children.