Table_3_Deciphering network dysregulations and temporo-spatial dynamics in disorders of consciousness: insights from minimum spanning tree analysis.xlsx

ObjectivesThe neural mechanism associated with impaired consciousness is not fully clear. We aim to explore the association between static and dynamic minimum spanning tree (MST) characteristics and neural mechanism underlying impaired consciousness.
MethodsMSTs were constructed based on full-length functional magnetic resonance imaging (fMRI) signals and fMRI signal segments within each time window. Global and local measures of static MSTs, as well as spatio-temporal interaction characteristics of dynamic MSTs were investigated.
ResultsA disruption or an alteration in the functional connectivity, the decreased average coupling strength and the reorganization of hub nodes were observed in patients with minimally conscious state (MCS) and patients with vegetative state (VS). The analysis of global and local measures quantitatively supported altered static functional connectivity patterns and revealed a slower information transmission efficiency in both patient groups. From a dynamic perspective, the spatial distribution of hub nodes exhibited relative stability over time in both normal and patient populations. The increased temporal variability in multiple brain regions within resting-state networks associated with consciousness was detected in MCS patients and VS patients, especially thalamus. As well, the increased spatial variability in multiple brain regions within these resting-state networks was detected in MCS patients and VS patients. In addition, local measure and spatio-temporal variability analysis indicated that the differences in network structure between two groups of patients were mainly in frontoparietal network and auditory network.
ConclusionOur findings suggest that altered static and dynamic MST characteristics may shed some light on neural mechanism underlying impaired consciousness.

研究目标：意识障碍相关的神经机制尚未完全阐明。本研究旨在探讨静态与动态最小生成树（minimum spanning tree, MST）特征与意识障碍潜在神经机制之间的关联。
研究方法：基于全脑功能性磁共振成像（functional magnetic resonance imaging, fMRI）信号及各时间窗内的fMRI信号片段构建最小生成树（MST）。本研究对静态MST的全局与局部测度，以及动态MST的时空交互特征展开了分析。
研究结果：最低意识状态（minimally conscious state, MCS）患者与植物状态（vegetative state, VS）患者均观察到功能连接的破坏或改变、平均耦合强度降低，以及枢纽节点重构现象。全局与局部测度分析定量证实了两组患者的静态功能连接模式发生改变，并揭示其信息传递效率均有所下降。从动态视角来看，正常人群与患者群体的枢纽节点空间分布均随时间呈现相对稳定性。MCS与VS患者的意识相关静息态网络内多个脑区的时间变异性升高，尤以丘脑为著；同时此类静息态网络内多个脑区的空间变异性亦有所升高。此外，局部测度与时空变异性分析表明，两组患者的网络结构差异主要集中于额顶网络与听觉网络。
研究结论：本研究结果提示，静态与动态MST特征的改变或可为阐明意识障碍的潜在神经机制提供新的思路。