Gong Gaolang, He Yong, Concha Luis, Lebel Catherine, Gross Donald W, Evans Alan C, Beaulieu Christian
Department of Biomedical Engineering, 1098 Research Transition Facility, University of Alberta, Edmonton, Alberta, Canada.
Cereb Cortex. 2009 Mar;19(3):524-36. doi: 10.1093/cercor/bhn102. Epub 2008 Jun 20.
The characterization of the topological architecture of complex networks underlying the structural and functional organization of the brain is a basic challenge in neuroscience. However, direct evidence for anatomical connectivity networks in the human brain remains scarce. Here, we utilized diffusion tensor imaging deterministic tractography to construct a macroscale anatomical network capturing the underlying common connectivity pattern of human cerebral cortex in a large sample of subjects (80 young adults) and further quantitatively analyzed its topological properties with graph theoretical approaches. The cerebral cortex was divided into 78 cortical regions, each representing a network node, and 2 cortical regions were considered connected if the probability of fiber connections exceeded a statistical criterion. The topological parameters of the established cortical network (binarized) resemble that of a "small-world" architecture characterized by an exponentially truncated power-law distribution. These characteristics imply high resilience to localized damage. Furthermore, this cortical network was characterized by major hub regions in association cortices that were connected by bridge connections following long-range white matter pathways. Our results are compatible with previous structural and functional brain networks studies and provide insight into the organizational principles of human brain anatomical networks that underlie functional states.
对构成大脑结构和功能组织基础的复杂网络拓扑结构进行表征是神经科学中的一项基本挑战。然而,关于人类大脑解剖连接网络的直接证据仍然稀缺。在此,我们利用扩散张量成像确定性纤维束成像技术,在大量受试者(80名年轻成年人)中构建了一个宏观尺度的解剖网络,以捕捉人类大脑皮层潜在的共同连接模式,并进一步用图论方法定量分析其拓扑特性。大脑皮层被划分为78个皮质区域,每个区域代表一个网络节点,如果纤维连接的概率超过统计标准,则认为两个皮质区域是相连的。所建立的皮质网络(二值化)的拓扑参数类似于以指数截断幂律分布为特征的“小世界”结构。这些特征意味着对局部损伤具有高弹性。此外,该皮质网络的特征是联合皮质中有主要枢纽区域,这些区域通过沿着长程白质通路的桥接连接相连。我们的结果与先前关于大脑结构和功能网络的研究结果一致,并为构成功能状态基础的人类大脑解剖网络的组织原则提供了见解。