| Abstract: | 本研究欲了解學齡期注意力不足過動症—混合表現型（Attention-Deficit/ Hyperactivity Disorder-Combined Presentation, ADHD-C）兒童執行功能表現，並檢視執行功能作業表現作為區分ADHD-C及一般兒童之區辨效能。研究對象共60名兒童，為國小一年級至六年級學童，包括30名目前未服藥且無其他精神科共病的ADHD-C兒童，以及配對年齡、智商與性別之30名控制組兒童；另有兒童家長及教師。探討二組兒童於五項執行功能領域（含八細項）之能力差異，分別為抑制（抑制正進行反應及干擾控制）、工作記憶（語文及視覺空間工作記憶）、認知彈性、計畫、流暢度（語文及非語文流暢度）。兒童依序接受WISC-IV簡式版及執行功能作業，家長與教師填答注意力缺陷過動症中文版。進行輪廓分析及典型區辨分析，探討執行功能差異及作業的區辨效能。結果顯示，ADHD-C兒童的執行功能整體輪廓與控制組並無不同，但整體表現低於控制組，且以干擾控制能力、視覺空間工作記憶能力、認知彈性能力顯著較差，而計畫、流暢度能力亦有偏低現象。各項作業上，以敲與拍作業、空間記憶廣度分測驗及兒童數－色測驗等三項，可有效區辨二組兒童，區辨分析指出整體區辨正確率為78.3%。總結來說，學齡期ADHD-C兒童執行功能呈現全面性偏低的能力，尤其在抑制、視覺空間工作記憶及認知彈性上更為明顯。本文最後提出未來研究上的發展及在臨床及教育上的應用。
Purpose: Children with attention-deficit/hyperactivity disorder (ADHD) who have executive function (EF) deficit show inconsistency in patterns of EF impairments. Certain methodological limitations might contribute to these confounding factors, such as ADHD subtype, intelligence quotient (IQ), chronological age, psychiatric comorbidity, and medication. This study examined the EF patterns in elementary school children with ADHD-combined presentation (ADHD-C) and determined whether EF tasks could help in effectively distinguishing between children with ADHD-C and controls. Methods: Sixty children from several elementary schools, their parents, and their teachers were recruited. Thirty children with ADHD-C and 30 healthy controls who were matched for sex, age, and IQ were enrolled. All the children with ADHD-C who were recruited had either never taken ADHD medication or had discontinued the medication at least a year before the study. Children with other psychiatric comorbidities were also excluded. Each child was tested on five major EF domains comprising eight different subdomains, including inhibition (of an ongoing response and interference control), working memory (verbal and nonverbal), cognitive flexibility, planning, and fluency (verbal and nonverbal). All the children were examined using the Wechsler Intelligence Scale for Children–Fourth Edition short form followed by the eight EF tasks. Parents and teachers in each group were required to finish the Swanson, Nolan, and Pelham Version IV scale for ADHD. Profile analyses were conducted to explore the differences in EF between the two groups. Canonical discriminant function analysis was used to determine whether a set of tasks effectively predicted ADHD-C. Results/Findings: The profiles of eight EF tasks were similar between the ADHD-C and control groups. Moreover, the global EF was relatively low in the ADHD-C group. Further analyses indicated that children with ADHD-C had poorer interference control, nonverbal working memory, and cognitive flexibility, and slightly lower levels in planning and in verbal and nonverbal fluency. Scores on the three EF tasks, including the knock and tap task, spatial working memory task, and the children’s color trial test, had an overall correct discriminative rate of 78.3% for the two groups. Conclusions/Implications: After the confounding factors were excluded, the study revealed that EF impairment may exist in children with ADHD-C. Compared to that in controls, EF performance was globally lower for children with ADHD-C. Among the EF subdomains, interference control, nonverbal working memory, and cognitive flexibility presented more deficits than the other subdomains, providing information about the phenotype of ADHD-C and the association with their neuropsychopathology. The clinical and educational implications of these findings are discussed. Further research on this subject is warranted. |
