Characteristics Of Production Of Prosody In Autistic Children

The disorder of prosody has a great influence on the expression of syntax,semantics,and emotions,which hinders the development of social communication among autistic children.Many studies abroad have shown that autistic children have difficult on the production of prosody,which is rarely studied in China.It's impossible for domestic researchers to entirely use foreign research conclusions for the influence caused by tone.Therefore,it's necessary to understand the prosodic characteristics of autistic children in the context of Mandarin.The study selects school-age autistic children?ASD?and children with typical development?TD?,who have same language ability and explored the prosodic characteristics of autistic children on intonation,rhythm and stress.The following are main research results:1.Characteristics of production of intonation in autistic childrenThe characteristics of production of intonation are explored by acoustic analysis,which are represented by the average fundamental frequency?F₀?,the standard deviation of the fundamental frequency?F₀SD?,and the fundamental frequency range??F?.The mixed experiment design of 2?subject:ASD,TD?×3?emotion:happy,sad,angry?×4?4 kinds of tone?is applied for imitation task.The results show that except for F₀SD and?F in sad emotion,F₀,F₀SD,and?F in the three emotional intonation of ASD are significantly lower than those of TD.The mixed experiment design of2?subject:ASD,TD?×2?emotion:like,aversion?is applied for spontaneous task.The results showed that the F₀ of the two emotional intonation of ASD was significantly lower than that of TD,and there was no significant difference between F₀SD with TD.The?F of likeness of ASD was significantly lower than that of TD,and?F of aversion of ASD was no significant difference with TD.According to results,F₀SD and?F,which are in the majority of emotional type produced by autistic children are significantly lower than those in TD in both spontaneous and imitation tasks,suggesting that ASD have monotonous intonation.What's more,differences in F₀ may be influenced by age and still require further study.2.Characteristics of production of rhythm in autistic childrenThe characteristics of production of rhythm are explored by acoustic analysis.The characteristics are reflected by the speed,the number of pause and pause duration.The imitation task was explored through the mixed experiment design of 2?subject:ASD,TD?×3?sentence length:6?8?10?×3?target speech rate:slow,medium,and fast?.The results show that the number of pause and pause duration in ASD change similarly to TD,which increase with the length of the sentence and decrease with the speed of the target speech rate.However,the speech rate of ASD is faster than that of TD in the slow-and medium-speed,and there is no significant difference between the fast-speed with TD.The spontaneous tasks were explored through a single factor?subject type:ASD,TD?experimental design.The results show that there was no significant difference in the three acoustic indicators between ASD and TD.The results suggest that autistic children have a similar pause pattern to children with typical development,but they are lack of the ability to control speech rate,which show faster imitation speech rate.3.Characteristics of production of stress in autistic childrenThrough 2?subject:ASD,TD?×3?stress position:start of sentence,middle of sentence,end of sentence?two-factor mixed experimental design to study the characteristics of imitation stress characteristics,which were reflected by the relative average fundamental frequency??F₀?,relative average intensity??I?and relative time??D?.The results show that?F₀ and?D in start of sentence in ASD were significantly lower than those in TD,and the?D in the middle of sentence was significantly lower than that of TD,and?D in end of the sentence was significantly higher than that of TD.The difference in?D between the three stress positions of ASD was significant.It shows that?D in the end of sentences is significantly larger than that in the start or middle of sentences.Through 2?subject:ASD,TD?×3?stress position:start of sentence,middle of sentence,end of sentence?two-factor mixed experimental design to explore the characteristics of spontaneous stress,which are reflected by the accuracy of stress production.The results showed that the when stress in the start or middle of sentences,accuracy of stress production in ASD are significantly lower than TD.When in the end of sentences,accuracy in ASD are significantly higher than TD.The results suggest that autistic children have problems of stress production on the start and middle of sentence.They are prefer to place stress at the end of the sentence by lengthen duration of words.The following are the innovations of research:1.It's the first time to analyze the prosodic characteristics of children with autism in the Mandarin system by the quantification analysis method,which enriched the content of the characteristics of prosody production in autistic children in China.2.By comparing the commonalities and differences in acoustic parameters between autistic children and typical development children,we provide parameter basis for intervention strategies of autism children with disorder of prosody production.3.According to different prosody production tasks,suitable experimental material is compiled.Under imitation task,the experimental materials reduce the influence of tone on intonation and stress;under spontaneous task,experimental materials has ecological validity,avoiding the"floor effect"in previous research.