OBJECTIVETo investigate the characteristics of working memory ability on emotional faces and related event-related potential (ERP) in children with autism spectrum disorder (ASD).

METHODSThe 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.

RESULTSCompared 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.

CONCLUSIONSThere 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.