目的： 近年來兒童早期非語言溝通能力逐漸受到重視，被認為是兒童未來語言、人際社會、認知發展的基礎。而以往研究顯示普拉德-威利症候群（Prader-Willi syndrome, PWS）兒童，在語言能力發展上多有遲緩現象，且有人際互動上的困難。然而目前並無PWS兒童非語言溝通能力的研究。本研究的目的在於探討PWS兒童早期非語言溝通能力發展的特徵。

病人與方法： 研究對象是1998-2002間全國送至成大醫院分子遺傳實驗室進行基因檢測確認為PWS的個案，選取生理年齡為二至七歲之兒童進行評估研究。本研究共收集PWS兒童16人（生理年齡：44.0±14.9個月），配對心智發展年齡相近的16位唐氏症兒童（生理年齡：45.4±15.7個月）及30位正常發展兒童（生理年齡：22.5±6.1個月）。利用ESCS (Early Social Communication Scale) 工具進行非語言溝通能力的評量，並比較三組兒童在主動性、反應性、低層次、高層次的非語言溝通能力發展上的類別差異。

結果： 非語言溝通能力的分析比較結果，PWS組在ESCS作業上的總行為次數，以及在相互注意協調能力、要求能力、社會互動能力三類不同功能之非語言溝通行為的平均反應次數，與正常組並無明顯差異。低、高層次的行為分析發現，其低層次的行為比率則明顯高於正常組。各行為類型的分析顯示，PWS兒童在主動性的相互注意協調能力部分，高於正常組及唐氏症組的表現，但PWS兒童傾向使用眼光接觸、眼光交替的低層次互動行為。而使用手指指示的高層次相互注意協調能力部分則低於正常兒童。反應性相互注意協調能力部分，不論是近距離或遠距離指示的跟隨能力，PWS皆明顯低於正常組。在要求能力部分，PWS兒童在使用眼光交替、伸手拿取的低層次行為部分與正常兒童無差異，且高於唐氏症組，但在使用給予的高層次能力上明顯低於正常兒童。社會互動能力部分，不論在主動性、反應性及低、高層次的比較上，與正常組及唐氏症組皆無顯著差異。

結論： 本研究發現PWS兒童非語言溝通能力的發展，與正常兒童及唐氏症兒童有所差異。PWS兒童在總行為次數與正常兒童無差異的情況下，其低層次的行為比率仍明顯高於正常兒童。顯示PWS兒童人際互動的溝通行為次數與正常組無差別，非語言溝通能力的差異主要是在溝通行為類型運用的部分。PWS兒童在非語言溝通能力的運用，不論在分享式或工具式的表達上，皆傾向使用低層次的溝通行為。而在高層次的分享式及工具式的表達能力以及低、高層次的相互注意協調能力的理解發展上皆明顯落後。顯示其非語言溝通能力發展，停留在較低年齡層的運作技巧層面，在發展較高年齡層的運作技巧層面，似乎有明顯的遲滯及困難。因此針對這些高層次非語言溝通能力的提升，可作為早期療育介入的參考。而唐氏症兒童不論是在低、高層次的溝通行為次數皆有明顯低落現象，有別於PWS兒童的行為表現趨勢。因此不同生物機制的發展障礙兒童早期非語言溝通能力的評估，以及針對不同發展特徵所設計的治療模式介入，有其顯著的重要性。

Objective: Nonverbal communication skills provide a foundation for subsequent language, social and cognitive development in young children. Prader-Willi syndrome (PWS) is a multiple congenital anomaly syndrome associated with mild to moderate mental retardation. This disorder is cause by genetic deficit in 15q11-q13 deletion (approximately 70%), chromosome 15 uniparental disomy (approximately 29%), or imprinting center mutations (approximately 1-2%). Children with PWS often have language developmental delay, and difficulty maintaining social interactions with peers. However there is no research on the nonverbal communication skills of individuals with PWS. This study examined the nonverbal communication competence of children with PWS.
Materials and Methods: All PWS subjects were confirmed by molecular genetic testing at the Molecular Cytogenetics Laboratory of National Cheng Kung University Medical Center from 1998 to 2002. The PWS group consisted of 16 children aged between 2 and 7 years. Sixteen children with Down syndrome and twenty-six normal children matched to PWS children with mental age were recruited. An early social communication scale was used to assess nonverbal communication skills in all subjects. The procedures of analysis of variance were conducted to compare differences between initiation and response behaviors, and differences between low- and high-level behaviors.
Results: We found that there were significant differences among the 3 groups in the low- and high-level behaviors. Children with PWS used significantly more low-level joint attention behaviors than did the Downs and normal children. However, the PWS children performed significantly fewer low- and high-level responses to joint attention behaviors, fewer high-level initiating joint attention behaviors, fewer high-level request behaviors than did in normal children. There were no difference in total behaviors frequency between the PWS and normal children, but the PWS children undertook significantly higher proportion in low-level behaviors compared to normal children.
Conclusions: The PWS children used significantly more low-level nonverbal communication behaviors and significantly fewer high-level behaviors than did in normal children. These findings suggested that children with PWS displayed significantly delayed development in high-level of nonverbal communication skills. There were also different profiles in development of nonverbal communication skills between the children with PWS and Downs. Therefore, nonverbal communication skills is important in the evaluation of the developmental characteristics and in design for specific early intervention program for children with different etiology of developmental delay including PWS and Down syndrome.

姜忠信（民89）。自閉症兒童意圖能力之研究。國立台灣大學心理學研究所博士論文。
林姿伶（民92）。自閉症幼兒非語言溝通能力之研究。中原大學心理學系碩士論文。
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