فهرست نشریات علمی دسترسی آزاد ایران

Autism is a neurodevelopmental disorder which is characterized by difficulty in social interaction, language and communication. In the present study, F0 of onset as a feature which can distinguish voiced from voiceless plosives has been acoustically analyzed in the speech production of two groups of autistic and normal developing children. The first group containing 7 girls and 13 boys with autism spectrum disorders (ASD), and the second group seven girls and 13 typically developing (TD) boys. Children were six to ten years old. Monosyllabic CVC words having oral plosives /p, b, t, d, k, g, G/ in the initial position followed by back vowel /æ/ were recorded in a sound-proof room using Praat Software. Acoustic analysis of uttered syllables confirmed that the speech of ASD children was different from that of TD peers. Significantly more plosives produced by ASD children were deleted because of unusual production. The differences between voiced and voiceless plosives were much more in TD children, which means ASD children distinguished these plosives slightly. Concerning gender, there were not significant differences between girls and boys of ASD and TD because they were before puberty. Considering different places of articulation, the onset F0 of ASD children was significantly lower than TD peers. The total results demonstrate that ASD children need more training and practice to become similar to TD peers in the production of initial plosive consonants.