Zhu Qiang, Cai Weiwei, Zheng Jianyong, Li Guanya, Meng Qianqian, Liu Qiaoyun, Zhao Jizheng, von Deneen Karen M, Wang Yuanyuan, Cui Guangbin, Duan Shijun, Han Yu, Wang Huaning, Tian Jie, Zhang Yi, Nie Yongzhan
Center for Brain Imaging, School of Life Science and Technology, Xidian University, Xi'an, Shaanxi 710071, China.
Xijing Gastrointestinal Hospital, the Fourth Military Medical University, Xi'an, Shaanxi 710032, China.
Neurosci Lett. 2016 Oct 6;632:141-6. doi: 10.1016/j.neulet.2016.08.042. Epub 2016 Aug 25.
Functional constipation (FC) is a common functional gastrointestinal disorder (FGID) with a higher prevalence in clinical practice. The primary brain regions involved in emotional arousal regulation, somatic, sensory and motor control processing have been identified with neuroimaging in FGID. It remains unclear how these factors interact to influence the baseline brain activity of patients with FC. In the current study, we combined resting-state fMRI (RS-fMRI) with Granger causality analysis (GCA) to investigate the causal interactions of the brain areas in 14 patients with FC and in 26 healthy controls (HC). Our data showed significant differences in baseline brain activities in a number of major brain regions implicated in emotional process modulation (i.e. dorsal anterior cingulate cortex-dACC, anterior insula-aINS, orbitofrontal cortex-OFC, hippocampus-HIPP), somatic and sensory processing, and motor control (i.e., supplementary motor area-SMA, precentral gyrus-PreCen) (P<0.05, FDR correction). The GCA results revealed stronger effective connectivity from the OFC and dACC, which are regions involved with emotional regulation, propel limbic regions at the aINS and HIPP to induce abnormal emotional processing regulating visceral responses; and weaker effective connectivity from the SMA and PreCen, which are regions involved with somatic, sensory and motor control, propel the aINS and HIPP, suggesting abnormalities of sensory and behavioral responses. Such information of basal level functional abnormalities expands our current understanding of neural mechanisms underlying functional constipation.
功能性便秘（FC）是一种常见的功能性胃肠疾病（FGID），在临床实践中患病率较高。通过神经影像学已确定FGID中涉及情绪唤醒调节、躯体、感觉和运动控制处理的主要脑区。目前尚不清楚这些因素如何相互作用以影响FC患者的基线脑活动。在本研究中，我们将静息态功能磁共振成像（RS-fMRI）与格兰杰因果分析（GCA）相结合，以研究14例FC患者和26例健康对照（HC）脑区之间的因果相互作用。我们的数据显示，在涉及情绪过程调节（即背侧前扣带回皮质-dACC、前岛叶-aINS、眶额皮质-OFC、海马-HIPP）、躯体和感觉处理以及运动控制（即辅助运动区-SMA、中央前回-PreCen）的多个主要脑区，基线脑活动存在显著差异（P<0.05，FDR校正）。GCA结果显示，来自OFC和dACC（与情绪调节相关的区域）的有效连接更强，推动aINS和HIPP的边缘区域诱导调节内脏反应的异常情绪处理；而来自SMA和PreCen（与躯体、感觉和运动控制相关的区域）的有效连接较弱，推动aINS和HIPP，提示感觉和行为反应异常。这种基础水平功能异常的信息扩展了我们目前对功能性便秘潜在神经机制的理解。
