第十二屆 自閉症兒童面孔認知事件相關電位的PrN170研究

A PrN170 ERP Study of Face Recognition in Autistic Children
樊越波、揭曉鋒、範楷
Yue-Bo Fan , Xiao-Feng Jie , Kai Fan

廣州兒童自閉症康復研究中心,廣州市康納學校
Guangzhou Rehabilitation and Research Centre for Children with ASD,Guangzhou Cana School 

研究背景與目的：  近些年的研究提示面孔認知的異常可能是導致自閉症社交功能缺陷的重要原因之一，雖然目前主要的行為學研究傾向於提示自閉症的面孔識別存在缺陷，但由於行為學的研究需要兒童的主動認知加工的參與，難以客觀地反映自閉症兒童的神經系統認知加工過程。本文通過事件相關電位的研究探討孤獨症兒童與普通兒童在面孔識別上的差異。

方法： 以中性表情的面孔以及物件照片為刺激材料，以兒童喜歡物件的照片作為靶刺激，採用32導事件相關電位儀，分別記錄20名自閉症兒童與22名普通兒童的腦電，比較兩類兒童在不同刺激下PrN170(Precursor N170,PrN170)成分。採用SPSS13.0進行資料處理分析。

結果：自閉症兒童組按鍵任務反應時較普通兒童組長（P<0.05），正確率無差別（P>0.05）；兩組兒童在面孔刺激呈現後約220ms顳枕葉導聯發現PrN170，兩組間對於不同類型的圖片刺激，PrN170波幅與潛伏期均未見差異（P>0.05）。
結論： 本次研究結果顯示自閉症兒童的面孔結構編碼過程無顯著異常，與以往的行為學實驗的結果不一致。然而PrN170僅能反映面孔識別的結構編碼階段，尚難確定自閉症兒童面孔識別的後期加工是否異常。

關鍵字：自閉症   事件相關電位   面孔識別   N170    

A Prn170 ERP Study of Face Recognition in Children with Autism
Background and Objective: Recent evidence indicates that face recognition impairment is one of the most commonly cited aspects of the social deficits among children with autism. Although behavioral evidence suggests that persons with autism have impairment in face recognition, it is difficult to observe objectively the face recognition neurologic processing. This study utilized 32 channels event-related potentials to investigate differences in face recognition between children with autism and typical development.  
Method: Electrical event-relateds were recorded to photos of neutral facial expression and objects in 20 autistic children and 22 typical children. In the experiment, the photo of a favorite is set for target. Then make a comparison under different stimulus. The data were analyzed by SPSS13.0.
Results:  Autistic children need more time in the tasks (p<0.05) ,but no difference in accuracy rate（P>0.05）. Precursor N170 was found in temporal and occipitalregions at around 220ms or so in two groups of children. There is no difference in amplitude and latency of two groups（P>0.05）.
Conclusion: The result is inconsistent with that of previous behavioral evidence, which suggests that there is no obvious abnormality of facial structural Coding Processes in Autistic Children. As PrN170 is limited to the facial structural Coding Processes, it is currently unknown whether it is normal for children with autism in face recognition post-processing.

Key words: autism, event-related potential, face recognition, N170