Centre for Neuroimaging & Cognitive Genomics (NICOG), Clinical Neuroimaging Laboratory, NCBES Galway Neuroscience Centre, College of Medicine, Nursing, and Health Sciences, National University of Ireland Galway, Galway, Ireland.
College of Engineering and Informatics, National University of Ireland Galway, Galway, Ireland.
Brain Connect. 2019 Dec;9(10):745-759. doi: 10.1089/brain.2019.0667. Epub 2019 Dec 3.
Well-established structural abnormalities, mostly involving the limbic system, have been associated with disorders of emotion regulation. Understanding the arrangement and connections of these regions with other functionally specialized cortico-subcortical subnetworks is key to understanding how the human brain's architecture underpins abnormalities of mood and emotion. We investigated topological patterns in bipolar disorder (BD) with the anatomically improved precision conferred by combining subject-specific parcellation/segmentation with nontensor-based tractograms derived using a high-angular resolution diffusion-weighted approach. Connectivity matrices were constructed using 34 cortical and 9 subcortical bilateral nodes (Desikan-Killiany), and edges that were weighted by fractional anisotropy and streamline count derived from deterministic tractography using constrained spherical deconvolution. Whole-brain and rich-club connectivity alongside a permutation-based statistical approach was used to investigate topological variance in predominantly euthymic BD relative to healthy volunteers. BP patients ( = 40) demonstrated impairments across whole-brain topological arrangements (density, degree, and efficiency), and a dysconnected subnetwork involving limbic and basal ganglia relative to controls ( = 45). Increased rich-club connectivity was most evident in females with BD, with frontolimbic and parieto-occipital nodes not members of BD rich-club. Increased centrality in females relative to males was driven by basal ganglia and fronto-temporo-limbic nodes. Our subject-specific cortico-subcortical nontensor-based connectome map presents a neuroanatomical model of BD dysconnectivity that differentially involves communication within and between emotion-regulatory and reward-related subsystems. Moreover, the female brain positions more dependence on nodes belonging to these two differently specialized subsystems for communication relative to males, which may confer increased susceptibility to processes dependent on integration of emotion and reward-related information.
已经确定的结构异常主要涉及边缘系统，与情绪调节障碍有关。理解这些区域与其他功能专门的皮质下子网的排列和连接是理解人类大脑结构如何支持情绪和情感异常的关键。我们通过结合基于体素的分割/分段和使用高角度分辨率扩散加权方法得出的非张量跟踪轨迹，用解剖学上改进的精度来研究双相情感障碍（BD）的拓扑模式。使用 34 个皮质和 9 个皮质下双侧节点（Desikan-Killiany）构建了连接矩阵，并使用受约束的球谐反卷积从确定性跟踪轨迹中得出各向异性分数和流线计数来加权边缘。全脑和丰富俱乐部连接以及基于置换的统计方法用于研究相对于健康志愿者的主要情绪稳定的 BD 中的拓扑变化。BP 患者（n=40）表现出全脑拓扑排列（密度、度和效率）的障碍，以及与对照组（n=45）相比涉及边缘和基底节的连接不良的子网。BD 中女性的丰富俱乐部连接增加最为明显，额叶边缘和顶枕部节点不是 BD 丰富俱乐部的成员。女性相对于男性的中枢性增加是由基底节和额颞边缘节点驱动的。我们的基于体素的皮质下非张量连接组图谱提供了一个 BD 去连接的神经解剖模型，该模型涉及情绪调节和奖励相关子系统内和子系统之间的通信。此外，与男性相比，女性大脑对属于这两个不同专门化子系统的节点的依赖程度更高，以便进行通信，这可能会增加对依赖于情绪和奖励相关信息整合的过程的敏感性。
