Functional Connectivity Density in the Sensorimotor Area is Associated with Sleep Latency in Patients with Primary Insomnia

Abstract

Bin Ji,1 Min Dai,2 Zhongwei Guo,3 Jiapeng Li,4 Yulin Cao,4 Zhenzhong Zhang,3 Yan Zhang,3 Xiaozheng Liu2 1Department of Anesthesiologyand Perioperative Medicine, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, 325027, People’s Republic of China; 2Department of Radiology of the Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, People’s Republic of China; 3The Sleep Medical Center of Tongde Hospital of Zhejiang Province, Hangzhou, Zhejiang, 310012, People’s Republic of China; 4Department of Radiology of Tongde Hospital of Zhejiang Province, Hangzhou, Zhejiang, 310012, People’s Republic of ChinaCorrespondence: Yan ZhangThe Sleep Medical Center of Tongde Hospital of Zhejiang Province, No. 234 Gucui Road, Hangzhou, Zhejiang, 310012, People’s Republic of ChinaEmail [email protected] LiuDepartment of Radiology of the Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, No. 109 Xueyuan West Road, Wenzhou, Zhejiang, 325027, People’s Republic of ChinaEmail [email protected]: It is unclear whether the patterns of functional connectivity density (FCD) differ between patients with primary insomnia (PI) and healthy subjects. In the present study, we investigated the features of FCD in patients with PI using resting-state functional MRI (rsfMRI).Methods: rsfMRI datasets of 32 patients with PI and 34 healthy controls (HCs) were obtained using a 3-Tesla scanner. FCD analysis was performed to compare voxels with abnormal whole-brain functional connectivity with other voxels among patients with PI and HCs. Abnormal brain regions were then used as seed points for FC analysis.Results: Compared with HCs, patients with PI exhibited significantly decreased FCD in the left medial frontal gyrus and increased FCD in the left supplementary motor area (SMA). With the left medial frontal gyrus as the seed point, patients with PI showed decreased FC between the left medial frontal gyrus and the left fusiform gyrus compared with HCs. With the left SMA as the seed point, patients with PI exhibited increased FC between the left SMA and the right anterior cingulate gyrus. Correlation analysis revealed that the increased FCD values in the left SMA were positively correlated with sleep latency in patients with PI.Conclusion: Default-mode network and SMA dysfunctions may be related to the pathophysiology of PI.Keywords: primary insomnia, resting-state functional magnetic resonance imaging, functional connectivity density

Keywords

• primary insomnia
• resting-state functional magnetic resonance imaging
• functional connectivity density