Changes in functional connectivity in patients with acute mild traumatic brain injury based on a triple-network model: a resting state functional MRI study / 中华行为医学与脑科学杂志

Objective:To investigate the resting state functional connectivity changes of the " triple network model" composed of salient network (SN), executive control network (ECN) and default mode network (DMN) in patients with acute mild traumatic brain injury (mTBI).Methods:From August 2020 to December 2021, forty-five acute mTBI patients (mTBI group) and 40 healthy controls (HC group) with matched sex, age, and education were included.The Montreal cognitive assessment (MoCA) scale was used to evaluate the cognitive status of all subjects.The resting state network (RNS) was established based on independent component analysis (ICA), and the SN, ECN and DMN were extracted, then functional network connectivity (FNC) was analyzed.Subsequently, the correlation between functional connectivity abnormalities and the performance of cognitive impairment was analyzed.SPSS 19.0 was used for statistical analysis and double sample t test was used for comparison between the tow groups. Results:Compared with HC group, mTBI group had enhanced functional connectivity between SN(L-insula) (MNI: x, y, z=-36, 15, 0, t=3.693)and ECN (left superior parietal gyrus, L-SPG) (MNI: x, y, z=-33, -69, 54, t=3.333)(FDR adjust, P<0.05), and decreased functional connectivity between DMN(left superior frontal gyrus, L-SFG) (MNI: x, y, z=-30, 30, 42, t=-4.063)and DMN(L-angular gyrus)(MNI: x, y, z=-21, -66, 33, t=-4.101)(FDR adjust, P<0.05). For FNC analysis, functional network connectivity in SN(IC26)-DMN(IC8) was enhanced in the acute mTBI group and decreased between SN(IC26)-DMN(IC12) and ECN(IC3)-DMN(IC12). The changes of left superior parietal gyrus functional connection were negatively correlated with MoCA score ( r=-0.627, P<0.01), and SN (IC26) -DMN(IC12) connection was positively correlated with MoCA score ( r=0.411, P=0.005). Conclusions:In patients with acute mTBI, the resting functional connectivity changes within and between the networks of the " triple network model" composed of SN, ECN and DMN, and is related to the decline of cognitive function.This will help to better understand the neuropathological mechanism of acute mTBI and post-traumatic cognitive impairment, and may become an effective imaging marker for identifying and predicting cognitive impairment after mTBI.

Interhemispheric functional connectivity for Alzheimer's disease and amnestic mild cognitive impairment based on the triple network model / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

The purpose of this study was to explore the differences in interhemispheric functional connectivity in patients with Alzheimer's disease (AD) and amnestic mild cognitive impairment (aMCI) based on a triple network model consisting of the default mode network (DMN), salience network (SN), and executive control network (ECN). The technique of voxel-mirrored homotopic connectivity (VMHC) analysis was applied to explore the aberrant connectivity of all patients. The results showed that: (1) the statistically significant connections of interhemispheric brain regions included DMN-related brain regions (i.e. precuneus, calcarine, fusiform, cuneus, lingual gyrus, temporal inferior gyrus, and hippocampus), SN-related brain regions (i.e. frontoinsular cortex), and ECN-related brain regions (i.e. frontal middle gyrus and frontal inferior); (2) the precuneus and frontal middle gyrus in the AD group exhibited lower VMHC values than those in the aMCI and healthy control (HC) groups, but no significant difference was observed between the aMCI and HC groups; and (3) significant correlations were found between peak VMHC results from the precuneus and Mini Mental State Examination (MMSE) and Montreal Cognitive Scale (MOCA) scores and their factor scores in the AD, aMCI, and AD plus aMCI groups, and between the results from the frontal middle gyrus and MOCA factor scores in the aMCI group. These findings indicated that impaired interhemispheric functional connectivity was observed in AD and could be a sensitive neuroimaging biomarker for AD. More specifically, the DMN was inhibited, while the SN and ECN were excited. VMHC results were correlated with MMSE and MOCA scores, highlighting that VMHC could be a sensitive neuroimaging biomarker for AD and the progression from aMCI to AD.

The primary explore of the damage of the executive control network in major depressive disorder:a dynamic causal model on magnetoencephalography / 中华行为医学与脑科学杂志

Objective To investigate the interconnection of the executive control network in major depressive disorder when they recognized the sad facial stimuli,and to discuss the aberrant mechanism of emotion processing.Methods Twenty major depressive patients and 20 well-matched healthy volunteers participated in the experiment.The brain actions of all subjects were recorded by the magnetoencephalography (MEG) when they were required to distinguish the emotion face.Based on prior knowledge,the interested brain area consisted of the primary visual cortex (V1),the orbitofrontal cortex(OFC),the dorsolateral prefrontal cortex (DLPFC),the anterior cingulated cortex (ACC).Then constructing three competing models to select an optimal model by the method of dynamic causal model(DCM),finally the differences of the effective connections of the optimal model between the depressed patients and healthy controls were analyzed.Results According to the results of Bayesian model selection (BMS),model 1 had the most exceedance probability of 0.80 with the features that there were bidirectional modulatory connections between the OFC,ACC and DLPFC.Given the best model,the parameters of effective connectivity of the optimal model were extracted,and then two-sample t-test over the model 1 was adopted.The modulatory effective connectivity from the OFC to the DLPFC in both hemisphere(t=-2.73,P=0.0096;t=-3.01,P=0.0046) and the OFC to the ACC (t=-2.93,P=0.0057) in the left hemisphere were significantly reduced in MDD.Conclusion There exists abnormal function of executive control network in depressed patients,the decreased effective connections between the OFC and the DLPFC,as well as the OFC and the ACC,may have correlation with the negative