Shaojuan Qiu1, Feng Chen1, Guanmao Chen1, Yanbin Jia2, Jiaying Gong3, Xiaomei Luo1, Shuming Zhong2, Lianping Zhao4, Shunkai Lai2, Zhangzhang Qi1, Li Huang5, Ying Wang6. 1. Medical Imaging Center, First Affiliated Hospital of Jinan University, Guangzhou 510630, China. 2. Department of Psychiatry, First Affiliated Hospital of Jinan University, Guangzhou 510630, China. 3. Department of Radiology, Six Affiliated Hospital of Sun Yat-sen University, Guangzhou 510655, China. 4. Department of Radiology, Gansu Provincial Hospital, Gansu 730000, China. 5. Medical Imaging Center, First Affiliated Hospital of Jinan University, Guangzhou 510630, China. Electronic address: cjr.huangli@vip.163.com. 6. Medical Imaging Center, First Affiliated Hospital of Jinan University, Guangzhou 510630, China. Electronic address: johneil@vip.sina.com.
Abstract
BACKGROUND: Previous studies demonstrated that patients with bipolar disorder (BD) exhibited abnormal neural activity in multiple brain regions. However, no study has been conducted to identify regional intrinsic neural activity changes in BD II. In the present study, we used the regional homogeneity (ReHo) approach to explore the regional abnormal neural activity in bipolar II disorder METHODS: One hundred unmedicated patients with BD II depression and 100 healthy controls (HC) underwent the resting-state functional magnetic resonance imaging. The ReHo values of each voxel was calculated in the whole brain. The two-sample t-test and threshold-free cluster enhancement (TFCE) correction were applied for the ReHo analysis. RESULTS: Compared with the HC group, the BD II group showed significantly decreased ReHo in the left orbitofrontal cortex, and increased ReHo in the right precentral gyrus, right supplementary motor area and bilateral middle occipital gyrus (P < .05, TFCE corrected). LIMITATIONS: This study lacks the evidence of brain structural changes, and used the cross-sectional design which did not explore local alterations of remitted and manic patients. CONCLUSION: Our findings revealed abnormal local intrinsic neural activity during resting state which may contribute to the pathophysiology of bipolar II disorder. Particularly the disrupted balance between the prefrontal cortex and primary sensorimotor regions provides evidence for the unique pathological mechanism underlying BD.
BACKGROUND: Previous studies demonstrated that patients with bipolar disorder (BD) exhibited abnormal neural activity in multiple brain regions. However, no study has been conducted to identify regional intrinsic neural activity changes in BD II. In the present study, we used the regional homogeneity (ReHo) approach to explore the regional abnormal neural activity in bipolar II disorder METHODS: One hundred unmedicated patients with BD II depression and 100 healthy controls (HC) underwent the resting-state functional magnetic resonance imaging. The ReHo values of each voxel was calculated in the whole brain. The two-sample t-test and threshold-free cluster enhancement (TFCE) correction were applied for the ReHo analysis. RESULTS: Compared with the HC group, the BD II group showed significantly decreased ReHo in the left orbitofrontal cortex, and increased ReHo in the right precentral gyrus, right supplementary motor area and bilateral middle occipital gyrus (P < .05, TFCE corrected). LIMITATIONS: This study lacks the evidence of brain structural changes, and used the cross-sectional design which did not explore local alterations of remitted and manicpatients. CONCLUSION: Our findings revealed abnormal local intrinsic neural activity during resting state which may contribute to the pathophysiology of bipolar II disorder. Particularly the disrupted balance between the prefrontal cortex and primary sensorimotor regions provides evidence for the unique pathological mechanism underlying BD.