Background: The nodal brain network measures (e.g., centrality measures) are defined for a single node and the global network measures (e.g., global efficiency) are defined for the whole brain in the literature. But a meaningful group of nodes will be benefited from a formulation that applies to a group of nodes rather than a single node or the whole brain. The question such as “which brain lobe is more structurally central in the older-adult brain?” could be answered to some extent by the application of a centrality measure that applied to the group of nodes from each lobe. In the brain asymmetric studies, path-based global measures were applied to the left and right hemispherical networks separately, considering only intrahemispheric edges. However, for a valid comparison, such global measures should include the interhemispheric edges as well. This problem can be solved by considering both hemispherical nodes as two groups in one network.

中文翻译：

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节点组的脑网络测量：在正常衰老和阿尔茨海默病中的应用。

背景：在文献中，节点大脑网络度量（例如，中心性度量）是为单个节点定义的，全局网络度量（例如，全局效率）是为整个大脑定义的。但是一组有意义的节点将从适用于一组节点而不是单个节点或整个大脑的公式中受益。诸如“在老年人大脑中哪个脑叶在结构上更处于中心位置？”这样的问题。可以通过应用适用于每个叶的节点组的中心性度量来在一定程度上回答这个问题。在大脑不对称研究中，基于路径的全局测量分别应用于左右半球网络，仅考虑半球内边缘。但是，为了进行有效的比较，此类全局度量还应包括半球间边缘。