Exploring Changes In Resting-state Brain Networks Associated With Cognitive Function In Subclinical Depression And Clinical Depression

Objective: Explore the differences in brain function between depressed patients and subclinical depressed subjects based on the intra-and inter-network functional connectivity of resting-state f MRI brain networks,and provide a scientific basis for further exploration of brain function changes and interventions in subclinical depression and depressed patients.Methods: Based on resting state functional magnetic resonance imaging(rs-f MRI),independent component analysis(ICA)was used in this paper to analyze the depressive group(The brain network components were divided into the subclinical depression group(clinical depression)and the healthy control group.The network was divided into four major functional networks with seven subcomponents,including the anterior default mode network(aDMN),ventral default mode network(vDMN),dorsolateral default mode network(d DMN),and ventral default mode network(vDMN).Default mode network,d DMN),left executive control network(LECN),right executive control network(RECN),back side attention network(dorsal attention network(DAN)and salience network(SN)Subsequently,this paper compared spatial distribution maps of each of the above brain networks between groups to explore the altered functional connectivity within the resting brain networks in subclinical depression and depressed patients.In addition,functional network connectivity analysis(FNC analysis)was performed to explore the differences in functional connectivity between the above brain networks and correlation with clinical scales.On the basis of the above studies,this paper conducted further dynamic brain network analysis to explore the changes in brain network dynamics.Results:(1)Differences in intra-network connectivity: the functional connectivity between the DMN and the anterior cuneiform lobe,the dorsolateral superior frontal gyrus and the paracuneus was decreased to different degrees in the subclinical depressed group and the depressed group relative to healthy controls.The functional connectivity between the DMN and the periaqueductal cortex was significantly enhanced in the subclinical group relative to healthy controls,whereas the depressed group showed a significant decrease in the functional connectivity between the DMN and the periaqueductal cortex.Significantly reduced functional connectivity of the SN in the mid-orbital frontal gyrus in the depressed group relative to the subclinical depressed group and healthy controls,and significantly enhanced functional connectivity of the SN in both the anterior cuneiform and supplementary motor areas in the subclinical depressed group relative to the healthy controls and depressed group.In most brain regions of the bilateral ECN,the depressed group and the subclinical depressed group showed different trends in functional connectivity.(2)Inter-network connectivity analysis: the control group,depression group and subclinical depression group showed significant differences in functional network connectivity between aDMN and vDMN,aDMN and SN,aDMN and RECN,vDMN and RECN,LECN and RECN,and LECN and SN relative to healthy control group.Significant differences in functional connectivity between aDMN and RECN,vDMN and RECN,LECN and RECN,and LECN and SN were seen in the depressed and subclinical depressed groups relative to healthy controls.Whereas there was a significant reduction in the functional connectivity between aDMN and SN relative to healthy controls,and the subclinical depression group showed lower performance in aDMN and SN relative to the depression group.The subclinical depressed group showed a significant reduction in the direct functional connection between LECN and RECN relative to the depressed group and healthy controls,with no significant difference in the depressed group relative to the healthy controls.(3)The dynamic brain networks were further investigated and found that the healthy control,subclinical depressed and depressed groups showed significant incremental and decremental increases and decrements between state 2 and state 3,respectively.(4)Finally,this paper correlated the above differential brain imaging metrics with clinical metrics separately and found that the PANSS scale and HAMA scale were significantly correlated with some intra-network connectivity metrics,and the BDI-II scale showed significant correlations with both intra-and inter-network connectivity for individual networks.In general,there are group differences in the connections between the precuneus and multiple networks(vDMN,LECN,and SN).The functional connection between aDMN and the dorsolateral superior frontal gyrus in the depression group and the functional connection between LECN and the left inferior temporal gyrus,the right middle temporal gyrus,and the left inferior frontal gyrus of the insula were significantly different from those in the healthy control group.The clinical scales(PANNS and HAMA)of the depression group were significantly different.The functional connection between LECN and the left middle occipital gyrus of the subclinical depression group was significantly different from that of the healthy control group,and there was a significant correlation with the clinical scale(BDI-II)of the subclinical depression group.The static functional connection between vDMN and RECN in the subclinical depression group was significantly enhanced compared to the healthy control group,and it was significantly negatively correlated with BDI-II in the subclinical depression group.Compared with the healthy control group,the duration of stay in the clinical depression group and subclinical depression group was significantly decreased when the vDMN and SN were connected relatively high.CONCLUSION:Subclinical depression subjects and depression patients showed significant changes in the functional connections within and between networks compared to healthy control subjects,and subclinical depression subjects and depression patients showed significant changes within and between networks.Accordingly,this study suggests that precuneus as a reaction to the self-esteem of brain regions,between-group differences of multiple network function connections,which is related to changes in clinical depression and subclinical depression relative to normal brain network connections;LECN is an important brain network that reveals changes in the brain network connections of clinical depression and subclinical depression,and this change is significantly related to depressive symptoms,revealing that the decline in executive control ability in clinical depression and subclinical depression may be related to abnormal connections between LECN and left inferior temporal gyrus right middle temporal gyrus and opercular part of left inferior frontal gyrus;The significant change in the connection between vDMN and RECN relative to the normal person may be a specific change in subclinical depression,while the changes in the clustering state of the subclinical depression group and depression group indicate that the dynamic functional connection between vDMN and SN network changes in depression play an important role in the course of the depression.In summary,this study reveals the changes in functional networks related to the cognitive status of subclinical depression subjects and clinical depression patients from different perspectives of static and dynamic functional connections within and between networks.