State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.
PLoS One. 2012;7(7):e40390. doi: 10.1371/journal.pone.0040390. Epub 2012 Jul 6.
Numerous studies with functional magnetic resonance imaging have shown that the fusiform face area (FFA) in the human brain plays a key role in face perception. Recent studies have found that both the featural information of faces (e.g., eyes, nose, and mouth) and the configural information of faces (i.e., spatial relation among features) are encoded in the FFA. However, little is known about whether the featural information is encoded independent of or combined with the configural information in the FFA. Here we used multi-voxel pattern analysis to examine holistic representation of faces in the FFA by correlating spatial patterns of activation with behavioral performance in discriminating face parts with face configurations either present or absent. Behaviorally, the absence of face configurations (versus presence) impaired discrimination of face parts, suggesting a holistic representation in the brain. Neurally, spatial patterns of activation in the FFA were more similar among correct than incorrect trials only when face parts were presented in a veridical face configuration. In contrast, spatial patterns of activation in the occipital face area, as well as the object-selective lateral occipital complex, were more similar among correct than incorrect trials regardless of the presence of veridical face configurations. This finding suggests that in the FFA faces are represented not on the basis of individual parts but in terms of the whole that emerges from the parts.
大量使用功能磁共振成像的研究表明,大脑中的梭状回面孔区(FFA)在面孔感知中起着关键作用。最近的研究发现,面孔的特征信息(例如,眼睛、鼻子和嘴巴)和面孔的整体信息(即特征之间的空间关系)都在 FFA 中进行编码。然而,对于 FFA 中的特征信息是独立编码还是与整体信息结合编码,我们知之甚少。在这里,我们使用多体素模式分析通过将激活的空间模式与在存在或不存在面孔配置的情况下辨别面孔部分的行为表现相关联,来检查 FFA 中面孔的整体表示。在行为上,与存在面孔配置的情况相比,缺失面孔配置会损害对面孔部分的辨别能力,这表明大脑中存在整体表示。在神经上,只有当呈现真实的面孔配置时,FFA 中的激活空间模式在正确试次之间比在错误试次之间更相似。相比之下,无论是否存在真实的面孔配置,枕叶面孔区以及物体选择性外侧枕叶复合体中的激活空间模式在正确试次之间比在错误试次之间更相似。这一发现表明,在 FFA 中,面孔不是基于单个部分进行表示,而是基于各部分组合形成的整体进行表示。