Study On Brain Functional Abnormalities Of Generalized Anxiety Disorder Based On Resting Functional Magnetic Resonance Imaging

One of the most common mental disorders,generalized anxiety disorder is characterized by excessive and persistent worry and anxiety and highly prevalent in the general population.Patients with GAD often suffer from a variety of anxiety-related physical symptoms,such as difficulty in concentrating,irritability,muscle tension,and disturbed sleep,and thus have poor quality of life and social function.Although the functional and structural abnormalities of GAD have been extensively studied,the neuropathological mechanisms of the disease remain unclearTherefore,elucidating the neuropathological underpinnings of GAD and exploring the potential objective neuromarkers may improve the understanding of neural mechanisms and contribute to the enhancement of clinical treatment for GAD.In this study,the resting state functional magnetic resonance imaging(rs-fMRI)is used as the carrier,and the local dynamic phase synchronization and the three-network functional connection analysis method are mainly used to measure the local dynamic functional connection and large-scale network functional connection of GAD patients.Analysis to detect the pathophysiological mechanisms of GAD.The research content of this study is divided into the following two parts:The first part: previous studies have illustrated abnormalities in static brain activity and connectivity in patients with generalized anxiety disorder(GAD).However,the dynamic patterns of brain connectivity in GAD have not been fully explored.In this study,we aimed to investigate the dynamic patterns of local brain functional connectivity in GAD by using dynamic regional phase synchrony(DRePS),a newly developed method for assessing intrinsic dynamic local connectivity.A total of 50 patients with GAD and 45 healthy controls(HCs)underwent resting-state functional magnetic resonance imaging.Results revealed that the DRePS values in the bilateral inferior temporal gyrus,left caudate,left anterior insula,and left posterior insula regions of the patients with GAD decreased relative to those of the HCs,suggesting the alterations in emotional and cognitive processing in GAD.The DRePS value of the left anterior insula was negatively correlated with the Hamilton Anxiety Rating Scale(HAMA)scores.Moreover,the altered DRePS values in these regions were used as potential biomarkers for distinguishing patients with GAD from HCs.Therefore,theabnormal dynamic local brain connectivity in regions involved in emotional and cognitive processing may provide a novel perspective in understanding neuropathological mechanisms underlying GAD.The second part: it has been found that in general anxiety disorder,the default network(DMN),salience network(SN)and control executive network(CEN)often exhibit abnormal activities.However,the current research on the GAD brain network is mainly concentrated in a certain network,and there are relatively few studies on the interconnection or interaction between the internal networks of the brain.In this study,we used RS-fmri data to assess topological differences between resting-state networks between GAD patients and healthy controls.Select the important nodes in DMN,SN,CEN,and use the ROI method to explore the connectivity changes between the three networks in generalized anxiety disorder.A total of 81 GAD patients and 80 healthy controls received resting state functional magnetic resonance imaging.Our results found that the functional connection between the default network and the highlighted network was abnormal in generalized anxiety disorder,and we also found that the default internal network functional connectivity of GAD patients was also disordered compared with normal controls.The results show that there is a large-scale functional connectivity disorder between the three network networks and the network in the generalized anxiety disorder,which provides a new perspective for understanding the GAD physiological and pathological mechanism from the perspective of network analysis.In summary,this study reveals the changes in the dynamic functional connectivity of GAD local brain regions,which may reflect the key pathological features of GAD;On the other hand,the spatial organization characteristics of the brain network of GAD patients are explored using large-scale functional connectivity.These findings have also deepened our understanding of the pathophysiological mechanisms of GAD.