中文摘要：

目的：结合静息态功能连接方法,探讨＂临床治愈＂抑郁症（remitted major depressive disorder,r MDD）患者默认网络（default mode network,DMN）功能连接的变化。方法：对22例经过住院治疗达到r MDD标准的患者（患者组）和22名相匹配正常对照组进行静息态功能磁共振扫描,以DMN公认的内侧前额叶（medial prefrontal cortex,m PFC）和后扣带回（posterior cingulate cortex,PCC）为种子点,通过种子点与全脑的功能连接分析,使用双样本t检验比较两组的功能连接差异。结果：与正常对照组比较,患者组m PFC与右侧角回（t=3.96,P〈0.01）、右侧旁扣带回（t=4.57,P〈0.01）、右侧额下回（t=4.25,P〈0.01）功能连接增加,与左侧前扣带回（t=-3.50,P〈0.01）、右侧PCC（t=-3.57,P〈0.01）功能连接降低;PCC与左侧枕中回（t=3.47,P〈0.01）、右侧枕中回（t=4.18,P〈0.01）功能连接增加。结论：r MDD患者DMN功能连接仍存在异常,可能与反刍症状及注意等认知偏向未完全改善有关。

英文摘要：

Objective： To explore functional connectivity of default mode network（ DMN） in remitted depressive patients using resting state functional magnetic resonance image（ rs-f MRI）. Method： Twenty-two patients with remitted depression（ patients group） and 22 well matched healthy controls underwent rs-f MRI scan.Medial prefrontal cortex（ m PFC） and posterior cingulate cortex（ PCC） in DMN were selected as two regions of interest（ ROI）,and correlation analysis were used to measure the functional connectivity of ROI based voxelwise in patients group and healthy control. Two-sample t-test was used to compared the z-score between groups.Results： Compared with healthy controls,patients group showed significant increased functional connectivity between m PFC and right angular gyrus（ t = 3. 96,P〈 0. 01）,right middle cingulate cortex（ t = 4. 57,P〈 0. 01）,right inferior prefrontal cortex（ t = 4. 25,P 〈0. 01）,and significant decreased functional connectivity between m PFC and left anterior cingulate cortex（ t =- 3. 50,P 〈0. 01）,right PCC（ t =- 3. 57,P〈 0. 01）. Patients group showed significant increased functional connectivity between PCC and left（ t = 3. 47,P 〈0. 01） and right（ t = 4. 18,P〈 0. 01） middle occipital cortex. Conclusion： The results suggest that abnormal functional connectivities in DMN may exist in remitted depressed patients during resting state. These abnormalities may be associated with rumination and biased cognition in major depressive disorder.