Alternation Of Amplitude Of Low Frequency Fluctuation And Functional Connectivity In The Patients Of Parkinson′s Disease With Working Memory Impairment: A Resting-state FMRI Study

ObjectiveThrough the analysis of resting-state functional magnetic resonance imaging(rs-f MRI)data,in order to explore the characteristics of amplitude of low frequency fluctuation(Alff)and functional connectivity(FC)in patients with Parkinson’s disease and working memory impairment,and to explore its correlation with cognitive function in roder to reveal the abnormal neuronal activity and possiblity of brain regions related to working memory impirment neuroimaging mechanism.Methods1.Thirty-nine patients with primary PD from January 2019 to September 2020were enrolled,using Mini-Mental State Examination(MMSE),Digital Span Test[DST,including Digit Span Forward Test(DSFT)and Digital Span Backword Test(DSBT)],Draw Clock Test(CDT)and Verbal Fluency Test(VFT)to evaluate cognitive function,collect all subjects’resting state functional magnetic resonance imaging(rs-f MRI)DICOM data,according to DSFT score,divided into Parkinson’s disease with working memory impairment group(PD-WI group,17 cases)and Parkinson’s disease without working memory impairment group(PD-normal group,22 cases).2.Use the SPM12 software package based on Matlab2014b(https://www.mathworks.cn/products/matlab.html)platform(Https://www.fil.ion.ucl.ac.uk/spm/software/spm12),DPABIsoftware(http://rfmri.org/dpabi)and RESTplus software(http://restfmri.net/forum/REST＿V1.8)Preprocess the original image data;then use the RESTplus software ALFF module to calculate the resting state low frequency amplitude(ALFF)value of all subjects,use the GRF correction method to find the different brain areas,and extract the ALFF of the different brain areas Value,Spearman rank correlation analysis of the correlation between ALFF value and cognitive function in different brain areas.4.Take the difference brain area obtained by ALFF statistics as the region of interest(ROI),use the RESTplus software FC module to calculate the functional connection(FC)value of the difference brain area and the whole brain,and use the GRF correction method to find out the brain with difference in FC Area.result1.PD-WI group patients’MMSE total score(Z=-2.149,P=0.032)and memory(Z=-2.465,P=0.014),attention and calculation(Z=-2.239,P=0.025),language Function(Z=-2.575,P=0.010)scores,as well as DST(Z=-5.357,P=0.000),DSBT(Z=-3.967,P=0.000)and CDT(Z=-3.410,P=0.001)The scores are lower than the PD-normal group.2.Comparison of low-frequency amplitude ALFF:The ALFF value of PD-WI group patients was higher than that of PD-normal group.The brain areas were mainly located in the right posterior cingulate gyrus,right thalamus and right precuneus(GRF correction;voxel P<0.05,Cluster P<0.05),Spearman rank correlation analysis showed that the ALFF value after the right cingulate was negatively correlated with the DSFT score(r_s=-0.530,P=0.001)3.With the right posterior cingulate gyrus as the area of interest,the brain areas with elevated FC values in the PD-WI group were mainly located in the left orbital middle frontal gyrus and the right lingual gyrus(GRF correction;voxel P<0.05,cluster P<0.05).conclusion1.PD with working memory impairment have different degrees of cognitive dysfunction in multiple cognitive fields.2.The spontaneous neuronal activity in the right posterior cingulate gyrus of the core brain region of the brain default network is enhanced and its correction with the left orbital middle frontal gyrus and the right lingual gyrus,which is a compensation for early working memory impairment.