Data_Sheet_1_Altered topological organization of resting-state functional networks in children with infantile spasms.docx

Covering neuroimaging evidence has demonstrated that epileptic symptoms are associated with the disrupted topological architecture of the brain network. Infantile spasms (IS) as an age-specific epileptic encephalopathy also showed abnormal structural or functional connectivity in specific brain regions or specific networks. However, little is known about the topological alterations of whole-brain functional networks in patients with IS. To fill this gap, we used the graph theoretical analysis to investigate the topological properties (whole-brain small-world property and modular interaction) in 17 patients with IS and 34 age- and gender-matched healthy controls. The functional networks in both groups showed efficient small-world architecture over the sparsity range from 0.05 to 0.4. While patients with IS showed abnormal global properties characterized by significantly decreased normalized clustering coefficient, normalized path length, small-worldness, local efficiency, and significantly increased global efficiency, implying a shift toward a randomized network. Modular analysis revealed decreased intra-modular connectivity within the default mode network (DMN) and fronto-parietal network but increased inter-modular connectivity between the cingulo-opercular network and occipital network. Moreover, the decreased intra-modular connectivity in DMN was significantly negatively correlated with seizure frequency. The inter-modular connectivity between the cingulo-opercular and occipital network also showed a significant correlation with epilepsy frequency. Together, the current study revealed the disrupted topological organization of the whole-brain functional network, which greatly advances our understanding of neuronal architecture in IS and may contribute to predict the prognosis of IS as disease biomarkers.

现有神经影像学（neuroimaging）证据表明，癫痫症状与大脑网络的拓扑结构破坏密切相关。婴儿痉挛症（Infantile Spasms, IS）作为一种年龄特异性癫痫性脑病，其特定脑区或特定网络的结构或功能连接亦存在异常。然而，目前针对婴儿痉挛症患者全脑功能网络的拓扑改变的相关研究仍较为匮乏。为填补这一研究空白，本研究采用图论分析（graph theoretical analysis）方法，对17例婴儿痉挛症患者及34例年龄、性别匹配的健康对照者的拓扑特性（包括全脑小世界属性与模块交互特性）进行了探究。两组受试者的功能网络在0.05至0.4的稀疏度范围内均表现出高效的小世界架构。婴儿痉挛症患者则表现出异常的全局拓扑特性：其标准化聚类系数、标准化路径长度、小世界系数（small-worldness）、局部效率均显著降低，而全局效率显著升高，提示其大脑网络向随机化网络偏移。模块分析结果显示，默认模式网络（default mode network, DMN）与额顶网络内的模块内连接度显著降低，而扣带回-岛盖网络与枕叶网络之间的模块间连接度显著升高。此外，默认模式网络内的模块内连接度降低与癫痫发作频率呈显著负相关；扣带回-岛盖网络与枕叶网络间的模块间连接度亦与癫痫发作频率存在显著相关性。综上，本研究揭示了婴儿痉挛症患者全脑功能网络的拓扑组织破坏情况，这一发现极大地推进了我们对婴儿痉挛症患者神经元架构的认知，或可作为疾病生物标志物助力婴儿痉挛症的预后预测。