Gunji Atsuko, Goto Takaaki, Kita Yosuke, Sakuma Ryusuke, Kokubo Naomi, Koike Toshihide, Sakihara Kotoe, Kaga Makiko, Inagaki Masumi
National Institute of Mental Health, National Center of Neurology and Psychiatry, Kodaira, Japan.
Brain Dev. 2013 Apr;35(4):293-8. doi: 10.1016/j.braindev.2012.12.008. Epub 2013 Feb 8.
To reveal the neural substrate of communication difficulties in children with autism spectrum disorders (ASDs), we investigated the P300 component of event-related potentials (ERPs) as represented by the average of electroencephalography findings time-locked to events and behavior. Because the P300 amplitude influences attentional resource allocation during discrimination, the component elicited during perception of known and unknown faces should indicate familiarity processing.
Nine typically developing children (TD) and nine children with ASDs participated in this study (Experiment 1). The P300 amplitude in TD children was significantly larger during familiar face perception than during unfamiliar face perception (p<0.01). However, there was no evidence of familiarity effect in children with ASDs. In three children with ASDs, we also assessed the P300 amplitude during perception of a therapist's face one month before (baseline), a few days before and after social skills training (SST) sessions (Experiment 2). To evaluate the effect of familiarity on facial identity processing, we analyzed the therapist/unknown ratio of P300 amplitudes related to the face discrimination task as an index. The ratio was larger after SST sessions than before, but there was no difference in the ratio between baseline and before SST assessments.
The P300 might be influenced by attentional resource allocation depending on the stage of learning face identification in children with ASDs. We speculate that this approach to evaluating brain responses during facial identity recognition could be used as a tool to clarify children's communication difficulties.
为揭示自闭症谱系障碍（ASD）儿童沟通困难的神经基础，我们研究了事件相关电位（ERP）的P300成分，该成分通过与事件和行为时间锁定的脑电图结果平均值来表示。由于P300波幅在辨别过程中会影响注意力资源分配，因此在已知和未知面孔感知过程中诱发的该成分应能表明熟悉度处理情况。
9名发育正常的儿童（TD）和9名患有ASD的儿童参与了本研究（实验1）。TD儿童在熟悉面孔感知过程中的P300波幅显著大于不熟悉面孔感知过程中的波幅（p<0.01）。然而，没有证据表明ASD儿童存在熟悉度效应。在3名患有ASD的儿童中，我们还评估了在社交技能训练（SST）课程前一个月（基线）、课程前后几天对治疗师面孔感知过程中的P300波幅（实验2）。为评估熟悉度对面部身份处理的影响，我们分析了与面孔辨别任务相关的P300波幅的治疗师/未知比例作为指标。该比例在SST课程后比课程前更大，但在基线和SST评估前之间该比例没有差异。
P300可能会受到注意力资源分配的影响，这取决于ASD儿童学习面孔识别的阶段。我们推测，这种评估面部身份识别过程中大脑反应的方法可作为一种工具来阐明儿童的沟通困难。
