King's College London Institute of Psychiatry, London, UK.
Neuroimage. 2010 Jan 1;49(1):939-46. doi: 10.1016/j.neuroimage.2009.08.030. Epub 2009 Aug 20.
Perception of fearful faces is associated with functional activation of cortico-limbic structures, which has been found altered in individuals with psychiatric disorders such as schizophrenia, autism and major depression. The objective of this study was to isolate the brain response to the features of standardized fearful faces by incorporating principal component analysis (PCA) into the analysis of neuroimaging data of healthy volunteers and individuals with schizophrenia. At the first stage, the visual characteristics of morphed fearful facial expressions (FEEST, Young et al., 2002) were classified with PCA, which produced seven orthogonal factors, with some of them related to emotionally salient facial features (eyes, mouth, brows) and others reflecting non-salient facial features. Subsequently, these PCA-based factors were included into the functional magnetic resonance imaging (fMRI) analysis of 63 healthy volunteers and 32 individuals with schizophrenia performing a task that involved implicit processing of FEEST stimuli. In healthy volunteers, significant neural response was found to visual characteristics of eyes, mouth or brows. In individuals with schizophrenia, PCA-based analysis enabled us to identify several significant clusters of activation that were not detected by the standard approach. These clusters were implicated in processing of visual and emotional information and were attributable to the perception of eyes and brows. PCA-based analysis could be useful in isolating brain response to salient facial features in psychiatric populations.
对恐惧面孔的感知与皮质-边缘结构的功能激活有关，在精神障碍患者中，如精神分裂症、自闭症和重度抑郁症患者中，已经发现这些结构发生了改变。本研究的目的是通过将主成分分析（PCA）纳入健康志愿者和精神分裂症患者的神经影像学数据分析中，来分离大脑对标准化恐惧面孔特征的反应。在第一阶段，使用 PCA 对变形恐惧面部表情（FEEST，Young 等人，2002）的视觉特征进行分类，产生了七个正交因子，其中一些与情感上显著的面部特征（眼睛、嘴巴、眉毛）有关，而另一些则反映了不显著的面部特征。随后，将这些基于 PCA 的因子纳入 63 名健康志愿者和 32 名精神分裂症患者的功能磁共振成像（fMRI）分析中，他们执行了一项涉及 FEEST 刺激的内隐处理的任务。在健康志愿者中，发现对眼睛、嘴巴或眉毛的视觉特征有明显的神经反应。在精神分裂症患者中，基于 PCA 的分析使我们能够识别出几个未通过标准方法检测到的显著激活簇。这些簇与视觉和情感信息的处理有关，归因于对眼睛和眉毛的感知。基于 PCA 的分析可用于分离精神障碍人群中对显著面部特征的大脑反应。
