Wei Wang1, Zhaohui Peng2, Xiang Wang3, Peng Wang3, Qingchu Li3, Gang Wang4, Fangni Chen3, Xinglong Chen5, Shiyuan Liu6. 1. Department of Radilogy, Changzheng Hospital, The Navy Military Medical University, No.415 Fengyang Road, Huangpu District, Shanghai 200003, China; 71282 Hospital, Baoding 071052, China. 2. Department of Radilogy, Changzheng Hospital, The Navy Military Medical University, No.415 Fengyang Road, Huangpu District, Shanghai 200003, China; Department of Radilogy, The 960th Hospital of the PLA Joint Logistice Support Force, Jinan, Shandong Province 250031, China. 3. Department of Radilogy, Changzheng Hospital, The Navy Military Medical University, No.415 Fengyang Road, Huangpu District, Shanghai 200003, China. 4. The Second Community Healthcare Service Center of Zhengzhou Road, Luoyang 471000, China. 5. 71282 Hospital, Baoding 071052, China. 6. Department of Radilogy, Changzheng Hospital, The Navy Military Medical University, No.415 Fengyang Road, Huangpu District, Shanghai 200003, China. Electronic address: liushiyuan@smmu.edu.cn.
Abstract
BACKGROUND: Aberrant functional and structural connectivity are considered to be involved in the underlying neural mechanism of generalized anxiety disorder (GAD). However, alterations in functional and structural interactions between the bilateral hemispheres are rarely examined. The current study aimed to characterized interhemispheric resting-state functional connectivity and white matter microstructural integrity of the corpus callosum in patients with GAD. METHODS: Resting-state Blood oxygen level-dependent and diffusion tensor image were acquired for patients with GAD and healthy subjects. The two groups were matched in age, gender, education years. The voxel-mirrored homotopic connectivity (VMHC) of whole brain and white matter integrity of the corpus callosum (CC) were compared between the two groups. Their correlations with clinical measures were further performed. RESULTS: Compare to controls, decreased resting-state VMHC were found in the precentral gyrus, middle cingulate gyrus and insula/putamen in patients with GAD. No regions of increased VMHC were detected in GAD. Compared to controls, GAD patients showed decreased fractional anisotropy (FA) values in CC2. In GAD group, further Pearson's correlation analyses showed that VMHC of the midcingulate gyrus positively correlated with FA of CC2, FA of CC2 negatively correlated with anxiety severity. Further mediation analyses demonstrated that attenuated VMHC in bilateral midcingulate gyrus partly mediated the association between white matter integrity of CC2 sub-region and anxiety severity. CONCLUSION: Our findings suggested impairment of interhemispheric coordination in GAD. Moreover, disrupted interhemispheric connectivity correlated with anxiety severity in GAD. Our findings provided a novel clue about the neural mechanism of GAD, and may contribute to further deep exploration and treatment of GAD. LIMITATIONS: The study was lack of comparison with non-GAD anxiety disorders.
BACKGROUND: Aberrant functional and structural connectivity are considered to be involved in the underlying neural mechanism of generalized anxiety disorder (GAD). However, alterations in functional and structural interactions between the bilateral hemispheres are rarely examined. The current study aimed to characterized interhemispheric resting-state functional connectivity and white matter microstructural integrity of the corpus callosum in patients with GAD. METHODS: Resting-state Blood oxygen level-dependent and diffusion tensor image were acquired for patients with GAD and healthy subjects. The two groups were matched in age, gender, education years. The voxel-mirrored homotopic connectivity (VMHC) of whole brain and white matter integrity of the corpus callosum (CC) were compared between the two groups. Their correlations with clinical measures were further performed. RESULTS: Compare to controls, decreased resting-state VMHC were found in the precentral gyrus, middle cingulate gyrus and insula/putamen in patients with GAD. No regions of increased VMHC were detected in GAD. Compared to controls, GAD patients showed decreased fractional anisotropy (FA) values in CC2. In GAD group, further Pearson's correlation analyses showed that VMHC of the midcingulate gyrus positively correlated with FA of CC2, FA of CC2 negatively correlated with anxiety severity. Further mediation analyses demonstrated that attenuated VMHC in bilateral midcingulate gyrus partly mediated the association between white matter integrity of CC2 sub-region and anxiety severity. CONCLUSION: Our findings suggested impairment of interhemispheric coordination in GAD. Moreover, disrupted interhemispheric connectivity correlated with anxiety severity in GAD. Our findings provided a novel clue about the neural mechanism of GAD, and may contribute to further deep exploration and treatment of GAD. LIMITATIONS: The study was lack of comparison with non-GAD anxiety disorders.