Shen Kelly, Hutchison R Matthew, Bezgin Gleb, Everling Stefan, McIntosh Anthony R
Rotman Research Institute, Baycrest, Toronto, Ontario M6A 2E1, Canada,
Robarts Research Institute and Harvard University, Department of Psychology, Center for Brain Science, Cambridge, Massachusetts 02138, and.
J Neurosci. 2015 Apr 8;35(14):5579-88. doi: 10.1523/JNEUROSCI.4903-14.2015.
The structural organization of the brain constrains the range of interactions between different regions and shapes ongoing information processing. Therefore, it is expected that large-scale dynamic functional connectivity (FC) patterns, a surrogate measure of coordination between brain regions, will be closely tied to the fiber pathways that form the underlying structural network. Here, we empirically examined the influence of network structure on FC dynamics by comparing resting-state FC (rsFC) obtained using BOLD-fMRI in macaques (Macaca fascicularis) to structural connectivity derived from macaque axonal tract tracing studies. Consistent with predictions from simulation studies, the correspondence between rsFC and structural connectivity increased as the sample duration increased. Regions with reciprocal structural connections showed the most stable rsFC across time. The data suggest that the transient nature of FC is in part dependent on direct underlying structural connections, but also that dynamic coordination can occur via polysynaptic pathways. Temporal stability was found to be dependent on structural topology, with functional connections within the rich-club core exhibiting the greatest stability over time. We discuss these findings in light of highly variable functional hubs. The results further elucidate how large-scale dynamic functional coordination exists within a fixed structural architecture.
大脑的结构组织限制了不同区域之间的相互作用范围，并塑造了正在进行的信息处理过程。因此，可以预期，大规模动态功能连接（FC）模式作为脑区之间协调的替代指标，将与构成基础结构网络的纤维通路紧密相关。在这里，我们通过比较猕猴（食蟹猴）使用血氧水平依赖性功能磁共振成像（BOLD-fMRI）获得的静息态FC（rsFC）与来自猕猴轴突束追踪研究的结构连接性，实证检验了网络结构对FC动力学的影响。与模拟研究的预测一致，则rsFC与结构连接性之间的对应关系随着样本持续时间的增加而增加。具有相互结构连接的区域在时间上表现出最稳定的rsFC。数据表明，FC的瞬态性质部分取决于直接的基础结构连接，但动态协调也可以通过多突触通路发生。发现时间稳定性取决于结构拓扑，富俱乐部核心内的功能连接随时间表现出最大的稳定性。我们根据高度可变的功能枢纽来讨论这些发现。结果进一步阐明了在固定结构架构内如何存在大规模动态功能协调。
