功能性便秘是临床常见的功能性胃肠病，与大肠癌发病关系密切，严重影响患者的生活质量。针刺治疗本病具有良好疗效，可同时改善便秘症状及相关异常心理状态，但其有效的中枢作用机制尚不明确。前期神经影像学研究发现，功能性便秘患者在静息状态下，脑肠轴中重要的功能脑区存在异常的功能连接及脑白质微结构的改变，而针刺对部分功能连接异常脑区及脑白质微结构可能具有调节作用。本研究在前期研究基础上加以深化，提出“调节边缘系统-丘脑-皮层网络的脑区异常功能连接以及脑白质微结构，可能是针刺调节脑肠轴、改善结肠传输功能、对功能性便秘产生治疗作用的中枢机制”的假说，以功能性便秘患者为对象，针刺天枢穴为干预措施，假针刺、聚乙二醇及观察等待组作对照，基于静息态神经影像学技术，以特定脑区的功能连接和脑白质微结构为切入点，与患者自主排便次数、粪便性状及心理评估进行相关性分析，探讨针刺天枢穴治疗功能性便秘可能的中枢作用机制。

Functional constipation is a kind of common functional gastrointestinal disease. It seriously influences patients’ quality of life and is closely associated with colorectal carcinoma. Acupuncture is a traditional external treatment of traditional Chinese medicine. Previous studies have found that acupuncture could improve the spontaneous bowel movements, stool consistency and difficulty of defecation. Neuroimaging studies indicated that acupuncture might regulate the abnormal brain functional connectivity and the microstructure of cerebral white matter of patients with functional gastrointestinal disease. In this study, we promote the hypothesis that acupuncture could improve the function of defecation and the physiological and psychological factors by adjusting the abnormal functional connectivity of brain regions and the microstructure of cerebral white matter. The patients with functional constipation will be included in the study. By the use of functional magnetic resonance imaging technics, the study will focus on the regulation of brain regions functional connectivity and the change of cerebral white matter microstructure, in order to reveal the central mechanism of acupuncture at ST 25 for functional constipation, compared to sham acupuncture, Macrogol 4000 Powder and waiting list.