Stella Maris Scientific Institute, Viale del Tirreno, 331, I-56018, Calambrone, Pisa, Italy.
Behav Brain Res. 2013 Aug 15;251:155-62. doi: 10.1016/j.bbr.2012.10.040. Epub 2012 Nov 1.
Face processing is a neural mechanism that allows understanding social information and cues conveyed by faces, whose dysfunction has been postulated to underlie some of the behavioral impairments characterizing autism spectrum disorders (ASD). A special region of the cortex, the fusiform gyrus (FG), is believed to be the specific area for processing face features and emotions. However, behavioral, fMRI and ERP studies addressed to investigate the role of FG dysfunction in ASD have led to conflicting results. Using a high-density EEG system, we recorded the face-sensitive ERP to neutral and emotional (happiness and fearful) faces, as a measure of early activity of the FG, in children with high functioning ASD. By controlling a number of experimental and clinical variables that could have biased previous research--such as gaze direction, attention to tasks, stimulus appearance and clinical profiles--we aimed to assess the effective role of the FG in the face emotion processing deficit hypothesized in ASD. No significant differences in early face-sensitive ERP components were found between ASD and neurotypical children. However, a systematic latency delay and amplitude reduction of all early potentials were observed in the ASD group, regardless of the stimulus, although more evident for emotions. Therefore, we can assume a diffuse dysfunction of neural mechanisms and networks in driving and integrating social information conveyed by faces, in particular when emotions are involved, rather than a specific impairment of the FG-related face processing circuit. Nevertheless, there is need of further investigation.
面部处理是一种神经机制，允许理解社会信息和面部传达的线索，其功能障碍被认为是自闭症谱系障碍（ASD）的一些行为障碍的基础。大脑皮层的一个特殊区域，梭状回（FG），被认为是处理面部特征和情绪的特定区域。然而，针对 FG 功能障碍在 ASD 中的作用进行的行为、fMRI 和 ERP 研究得出了相互矛盾的结果。我们使用高密度 EEG 系统记录了高功能 ASD 儿童对中性和情绪（快乐和恐惧）面孔的面部敏感 ERP，作为 FG 早期活动的测量。通过控制可能会影响先前研究的一系列实验和临床变量，例如注视方向、对任务的注意力、刺激出现和临床特征，我们旨在评估 FG 在 ASD 中假设的面部情绪处理缺陷中的有效作用。ASD 儿童和神经典型儿童之间在早期面部敏感 ERP 成分上没有发现显著差异。然而，在 ASD 组中观察到所有早期电位的系统潜伏期延迟和振幅降低，无论刺激如何，尽管情绪更为明显。因此，我们可以假设在驱动和整合面部传达的社会信息方面，神经机制和网络存在弥散性功能障碍，特别是在涉及情绪时，而不是 FG 相关的面部处理回路的特定损伤。然而，需要进一步的研究。
