Study On The Functional Connectivity Between Resting State Functional Magnetic Resonance And Subjective Cognitive Decline

Objective: To investigate the pathogenesis of Subjective cognitive decline(SCD),and Mild cognitive impairment(MCI).Regional Homogeneity(ReHo)And functional connectivity(FC)Were used to study SCD and MCI in Resting-state.Methods: The current study uses a convenient sampling method to recruit elderly aged between 60 ~ 80 years old in the Wuxi community.The elderly people without diagnosed cognitive impairment that affect cognitive function and can complete all neuropsychological tests normally.Full-time doctors performed neuropsychological tests on all participants to rule out the effects of other factors on the study.The SCD group included 25 subjects,MCI groups 24,and 30 normal control groups with matching gender and education years.The 3.0T MR750 magnetic resonance instrument from the United States GE was used to perform a whole-brain scan on all subjects.The data and screening abnormal brain areas were analyzed and compared by DPARSFA2.3 and SPM8 software in the SCD group.Whole-brain FC analysis was performed with the posterior cingulate(PCC)/precuneus MNI(–2,-50,36)as seed points,Differential brain regions between MCI group,SCD group,and normal control group were analyzed.Results:Part one Neuropsychological assessment results 1 There were statistically significant differences in age among the MCI group,SCD group,and NC group(p<0.05),the differences in gender and years of education were not statistically significant(P> 0.05);2 There were statistically significant differences in the Montreal scale score,Hamilton depression scale score,and ADAS-Cog scale score among MCI group,SCD group,and NC group(P<0.05).Part two The ReHo and whole-brain FC analysis results 1 The regional homogeneity(ReHo)analysis results: Compared with the normal control(NC)control group,SCD subjects displayed higher ReHo indices in the Occipital_Mid_R,Calcarine_L,Lingual_R,Parietal_Sup_R,Precuneus_L(Voxel level,p-value<0.05,Alphasim correction),and ReHo values of Temporal_Inf_R,Frontal_Inf_Tri_R,Frontal_Inf_Orb_R,Thalamus_R,Thalamus_L Reduced(Voxel level,p-value <0.05,Alphasim correction);2 The functional connectivity(FC)analysis results between PCC /precuneus and the whole brain: Compared with the normal control(NC)control group,using PCC/ precuneus as seed voxels,the Whole-brain FC analysis showed that Cerebellum_Crus2_R,Cerebelum_Crus1_R,Cerebelum_Crus1_L increased in subjects with SCD(Voxel level,p-value<0.05,Alphasimcorrection),and reduced in Fronta_Inf_Orb_R,Insula_R,Putamen,Frontal_Mid_Orb_R,Caudate_R,Temporal_Mid_L,Insula_L,Temporal_Inf_L,Temporal_Pole_Sup,Rolandic_Oper_L(Voxel level,p-value<0.05,Alphasim correction).Conclusion: Subject cognitive decline as clinical early in AD,abnormalities in the core brain region of the default mode network may indicate early stages of AD,and the abnormal FC between PCC /precuneus and the whole brain may be more sensitive to disease prediction and would be a reliable biological indicator.