Objective: To investigate the characteristics of working memory ability on emotional faces and related event-related potential (ERP) in children with autism spectrum disorder (ASD).
Methods: The Chinese Facial Affective Picture System was used as test material, and the event-related potential system was used to record the electroencephalographic data when 16 ASD children aged 6-12 years (ASD group) and 14 normal children matched for age (control group) were completing the facial emotion delayed match-to-sample task. The characteristics of P3b component were analyzed for both groups.
Results: Compared with the control group, the ASD group had a significantly longer reaction time (1 527 ms vs 1 060 ms; P<0.05) and a significantly lower accuracy rate (76% vs 88%; P<0.01) in the facial emotion delayed match-to-sample task. There was a difference in the amplitude of P3b component during the encoding stage between the two groups. In the ASD group, the P3b component on the left side electrode had a higher amplitude than that on the right side electrode (P<0.05), while the control group had no such characteristics.
Conclusions: There is a difference in P3b component during the encoding stage between school-aged ASD children and normal children. In ASD children, working memory on emotional faces may depend more on the related neural pathway in the left hemisphere.
目的: 探讨孤独症谱系障碍（ASD）儿童表情面孔工作记忆能力及其事件相关电位（ERP）的特点。
方法: 以中国面孔表情图片系统为测试材料，采用事件相关电位系统分别记录16例6~12岁ASD儿童（ASD组）与14例年龄匹配的正常儿童（对照组）在完成表情面孔延迟样本匹配任务时的脑电成分，分析两组儿童脑电P3b成分的特点。
结果: ASD组儿童在表情面孔工作记忆任务中的总体反应时比对照组长（1 527 ms vs 1 060 ms，P < 0.05）、正确率比对照组低（76% vs 88%，P < 0.01）。ASD组和对照组间编码加工阶段的P3b成分波幅存在差异。ASD组左侧电极的P3b成分波幅值高于右侧电极波幅（P < 0.05），而对照组无此特点。
结论: 学龄期ASD儿童在表情面孔编码加工阶段的P3b成分异于正常发育儿童，其表情面孔工作记忆过程可能更多地依赖于左半球相关的神经通路。