Aberrant Cerebral Activity In Early Postmenopausal Women:A Resting-state Functional Magnetic Resonance Imaging Study

Backgrounds and objective:Early postmenopausal women frequently suffer from cognitive impairments and emotional disorders,such as lack of attention,poor memory,deficits in executive function and depression.However,the underlying mechanisms of these impairments remain unclear.Material and methods:1.Forty-three early postmenopausal women were selected as the experimental group,and forty-four age-and education level-matched premenopausal women were included in the study.All the participants underwent biochemical tests such as serum estrogen,follicle stimulating hormone,blood routine,and fasting blood glucose.Subsequently,the subjects were tested for neuropsychological tests,including state anxiety scale(SAS),self-rating depression scale(SDS),and kupperman scale,Pittsburgh sleep quality index(PSQI).2.Magnetic resonance data acquisition and processing.T1 structural image data was acquired by three-dimensional fast spoiled gradient recalled(3DFSPGR)scanning by GE 3.0T MR instrument,and the resting state function image was obtained by plane echo sequence(TE)scanning.The resting magnetic brain imaging data processing package(DPABI Version 2.3)was used to process the acquired magnetic resonance T1 structural image and resting state functional image data,and the common indicators such as degree of centrality(DC),low frequency amplitude(ALFF),regional homogeneity(ReHo)were calculated.Subsequently,the abnormal point of the above-mentioned indicators was used as the seed point for whole brain functional connection(FC)analysis by using REST1.8 software.4.After the MR data were collected,all participants were evaluated for cognitive function using Eprime software,including attention network(ANT),execution function(Stroop task),and working-memory(One-back task).Finally,the following data were statistically analyzed by SPSS 22.0 software: age,education level,follicle stimulating hormone level,ANT sub-network,Stroop-task RT,Two-back RT performed with two-sample t-test;Stroop-task ACC and Two-back ACC performed with chi-square test.Two-sample t-test was performed on the DC results and functional connection analysis results of the two groups(FDR correction,P < 0.05;SVC correction,continuous voxel > 20)by using the resting state functional magnetic resonance statistical parameter map toolkit(spm8).The correlations between abnormal DC value and changed FC value and follicle stimulating hormone level,anxiety and depression symptoms and cognitive function data of early postmenopausal women were analyzed.Results:1.General data There was no significant difference in age and education level between the two groups(P = 0.252,P = 0.459);early postmenopausal women had higher serum follicle stimulating hormone level(P < 0.001),Severe menopausal symptoms(P = 0.002),higher depression score(P < 0.001),worse sleep quality(P < 0.001),lower alertness(P = 0.033),poorer executive control(P = 0.010)),lower memory accuracy(P < 0.001),longer memory response time(P = 0.024),lower execution accuracy(P < 0.001),and longer executive reaction time(P = 0.003)than premenopausal women.2.Degree of centrality(DC)analysis Contrast to the premenopausal women,the early postmenopausal women showed the significantly increased DC value in left amygdala and the weakened DC value in bilateral occipital gyrus.3.Functional connection(FC)analysis When we used the AMYG.L as the seed point,FC with the left insula(INS.L),bilateral prefrontal cortex(PFC)and right superior frontal gyrus(SFG.R)was increased in the early postmenopausal women;when the MOG.L as the seed point,FC with the bilateral MOG,SFG.R,IPG.L,MFG.L was decreased in the early postmenopausal women;when the MOG.R as the seed point,FC with the right middle temperal gyrus(MTG.R),right inferior frontal gyrus(IFG.R),bilateral MOG,SFG.R,IPG.L,MFG.R was decreased in the early postmenopausal women.4.Correlation analysis Experimental group showed that the serum follicle stimulating hormone level was negatively correlated with the working memory accuracy(r =-0.331,P = 0.030);the enhanced functional connection strength between the left amygdala and the bilateral prefrontal cortex was positively correlated with the executive accurace(r = 0.387,P = 0.012);the enhanced functional connection strength between left amygdala and the left insula was positively correlated with depression score(r = 0.382,P = 0.019);The enhanced functional connection strength between left amygdala and the left insula was positively correlated with the Pittsburgh sleep quality score(r = 0.382,P = 0.041);The decreased functional connection strength between the MOG.L and the IPG.L was negative correlated with working memory response time(r =-0.322,P = 0.035);The weakened functional connection strength between the MOG.R and the IPG.L was negatively correlated with working memory response time(r =-0.313,P = 0.041).Conclusion:Early postmenopausal women found functional signals abnormalities in multiple brain regions associated with cognitive function,including left amygdala,bilateral occipital gyrus,left insula,bilateral prefrontal cortex,right superior frontal gyrus,left inferior parietal gyrus,left inferior parietal gyrus.Correlation analysis showed cognitive changes and menopausal symptoms in early postmenopausal women were associated with the corresponding functional brains.In summary,the results of our research may be an important neurophysiological basis for cognitive impairment and disease progression in early menopausal women.