Fairhall Scott L, Ishai Alumit
Institute of Neuroradiology, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland.
Cereb Cortex. 2007 Oct;17(10):2400-6. doi: 10.1093/cercor/bhl148. Epub 2006 Dec 26.
Face perception elicits activation within a distributed cortical network in the human brain. The network includes visual ("core") regions, as well as limbic and prefrontal ("extended") regions, which process invariant facial features and changeable aspects of faces, respectively. We used functional Magnetic Resonance Imaging and Dynamic Causal Modeling to investigate effective connectivity and functional organization between and within the core and the extended systems. We predicted a ventral rather than dorsal connection between the core and the extended systems during face viewing and tested whether valence and fame would alter functional coupling within the network. We found that the core system is hierarchically organized in a predominantly feed-forward fashion, and that the fusiform gyrus (FG) exerts the dominant influence on the extended system. Moreover, emotional faces increased the coupling between the FG and the amygdala, whereas famous faces increased the coupling between the FG and the orbitofrontal cortex. Our results demonstrate content-specific dynamic alterations in the functional coupling between visual-limbic and visual-prefrontal face-responsive pathways.
面部感知会引发人类大脑中一个分布式皮层网络的激活。该网络包括视觉（“核心”）区域，以及边缘和前额叶（“扩展”）区域，它们分别处理不变的面部特征和面部的可变方面。我们使用功能磁共振成像和动态因果模型来研究核心系统和扩展系统之间以及内部的有效连接性和功能组织。我们预测在面部观察期间核心系统和扩展系统之间存在腹侧而非背侧连接，并测试效价和知名度是否会改变网络内的功能耦合。我们发现核心系统以主要的前馈方式进行分层组织，并且梭状回（FG）对扩展系统施加主要影响。此外，情绪化面孔增加了FG与杏仁核之间的耦合，而知名面孔增加了FG与眶额皮质之间的耦合。我们的结果证明了视觉-边缘和视觉-前额叶面部反应通路之间功能耦合中特定内容的动态变化。
