自閉症類群障礙與發展遲緩幼兒共享式注意力與模仿能力的表現

Performance of Joint Attention and Imitation in Toddlers With Autism Spectrum Disorder and Those With Developmental Delay

本研究探討3歲以下自閉症類群障礙（autism spectrum disorder, ASD）與發展遲緩（developmental delay, DD）幼兒共享式注意力（joint attention, JA）與模仿能力障礙與表現型態，及JA與模仿和語言能力的關聯性。受試者為生理年齡25－36個月的ASD與DD幼兒各61名。以修訂臺灣版二歲期自閉症篩檢工具評估主動性JA（initiating JA, IJA）、回應性JA（responding JA, RJA）、物體操作及手勢動作模仿能力，IJA分為完整IJA（full-IJA, F-IJA）與部分IJA（partial-IJA, P-IJA）。以穆林發展量表測量語言理解、語言表達及整體語言，以適應行為評量系統第二版中文版－幼兒版測量溝通適應。共變數分析控制整體心理年齡後，ASD組的F-IJA、P-IJA、RJA顯著低於DD組，模仿能力無顯著差異。二因子混合設計變異數分析發現組別與非語言溝通能力的交互作用達顯著顯示ASD與DD組的JA與模仿能力存在不同表現型態，ASD組IJA表現最差，而DD組手勢動作模仿表現最差。階層迴歸探究ASD與DD幼兒語言能力的關聯因素，發現ASD組手勢動作模仿和語言理解、語言表達，以及溝通適應具顯著關聯性，P-IJA和語言表達具顯著關聯性，RJA和語言理解與溝通適應具顯著關聯性。DD組僅手勢動作模仿和語言表達具顯著關聯性。本研究顯示ASD幼兒主要缺陷為JA，模仿能力是落後而非缺陷，ASD幼兒在JA、模仿以及語言能力的發展順序不同於DD幼兒。ASD與DD幼兒JA與模仿能力表現型態的差異，導致兩組幼兒語言能力的關聯因素也不同。本研究結果可以作為ASD與DD幼兒早期篩檢與早期療育的參考。

Purpose: This study examined the performance and profiles of joint attention and imitation in toddlers with autism spectrum disorder (ASD) and those with developmental delay (DD). The contributions of joint attention and imitation to language development were also analyzed. Methods: The sample comprised 122 toddlers aged 25–36 months, comprising 61 toddlers with ASD and 61 toddlers with DD. The Taiwan version of the Screening Tool for Autism in Two-Year-Olds was modified and used for measuring joint attention and imitation, including initiating joint attention (IJA), responding joint attention (RJA), object imitation, and manual imitation. IJA was divided into full IJA (F-IJA) and partial IJA (P-IJA). In addition, the Mullen Scales of Early Learning and the communication subscale of the Chinese Adaptive Behavior Assessment System-II for infant or preschool children were used to measure language abilities and communication adaptation, respectively. Results/Findings: In analysis of covariance (which was controlled for mental age), toddlers with ASD exhibited significant impairment of F-IJA, P-IJA, and RJA instead of imitation compared with toddlers with DD. Two-way mixed analysis of covariance revealed a significant group x nonverbal communication abilities interaction. The results suggested that the profiles of joint attention and imitation of toddlers with ASD and those with DD were distinct. Toddlers with ASD showed weakest ability in IJA, whereas toddlers with DD showed weakest ability in manual imitation. Hierarchical regressions were used to examine the contributors to language development in the 2 groups. For toddlers with ASD, manual imitation was the strongest significant contributor to receptive language, expressive language, and communication adaptation, whereas P-IJA was the significant contributor to expressive language. In addition, RJA was the significant contributor to receptive language and communication adaptation. For toddlers with DD, only manual imitation was a significant contributor to expressive language. Conclusions/Implications: The findings of this study revealed that weak joint attention was the core deficit of toddlers with ASD. However, imitation was delayed instead of being a deficit in toddlers with ASD. The distinct profiles of the 2 groups suggested that the developmental sequence of joint attention and imitation differed between toddlers with ASD and toddlers with DD. Therefore, contributors to language development differed between toddlers with ASD and toddlers with DD. The results of the study offer implications for early screening and early intervention of toddlers with ASD and those with DD.