The Effect Of Baduanjin Exercise On Mild Cognitive Impairment:a Functional Imaging Study Based On The Default Mode Network

Objectives:Study 1:To evaluate the effcts of regular Baduanjin exercise on the cognitive function and different areas of the cognitive function in community MCI patients.Study 2:To explore the possible functional imaging mechanism based on default mode network(DMN)of Baduanjin exercise in improving the cognitive function of MCI patients.Methods:Study 1:A total of 135 eligible MCI elderly patients were randomly allocated into Baduanjin group,brisk walking group or health education group.Patients in the health education group only received cognition-related health education,and patients in the Baduanjin group and brisk walking group were required to participant in the Baduanjin or brisk walking exercise for 6 months based on the health education intervention.The Montreal Cognitive Assessment Scale(MoCA),the Wechsler Memory Scale(WMS),Auditory Vocabulary Learning Test(AVLT),Digital Signage Test,Trail Making Test(TMT)and the Go/No go test were performed to evaluate the global cognitive function,memory,processing speed,executive function and attention,respectively at pre-and post-intervention.Study 2:Based on the experimental design of study 1,23 patients with no contraindications of Magnetic Resonance Image(MRI)were randomly selected from each group.Functional MRI(fMRI)was performed before and after intervention.The DPABI software was used to preprocess the fMRI data.The independent component analysis(ICA)was performed using GIFT software.After extraction of DMN,the DPABI software was used for one-way ANOVA and post-hoc multiple comparisons.Finally,together with the results of the coginitive function tests which showed significant differences,the peak intensity values of the significantly different brain regions were extracted to perform the correlation analysis.Results:Study 1:There was no significant difference between the 3 groups on characteristics,such as age,educational history,etc.,except gender.And there was no significant difference between the 3 groups on the cognitive function test on baseline,except the reaction time of the Go/No go test.After the intervention,the MoCA score,total score and memory quotient of WMS, AVLT recall and Digit Symbol-Coding score were significantly different(P<0.05).The results of multiple comparisons showed that the scores of the above tests were significantly higer than that of the health education group(P<0.05).We also found that the brisk walking group performed better than the health education group,but the differences were not significant(P>0.05).The scores of MoCA,AVLT and Digit Symbol-Coding were significantly higher than those of fast walking group(P<0.05).However,there was no significant difference between groups on TMT and Go/No go test(P>0.05).Study 2:Before the intervention,there was no significant difference between the three groups on characteristics,such as age,gender,educational history,etc.(P>0.05).There were significant differences in the counting from 100 to 1,number of TMT-A errors and the reaction time of Go/No go test(P<0.05),and no significant differences in other tests(P>0.05)at baseline.After the intervention,there were significant differences between the 3 groups in the total and abstract thinking score of MoCA,total score and memory quotient of WMS,as well as in the counting from 1 to 100,picture recognition and comprehension memory in WMS(P<0.05).The results of the multiple comparisons showed that the scores of the above tests were significantly higher than those of the control group(P<0.05).It also showed that the scores of counting from 1 to 100 in the brisk walking group was significantly higher than that of the control group(P<0.05).While the total score and abstact thinking score of MoCA in Baduanjin group were significantly higher than those of the control group(P<0.05).The results of ICA showed that,compaired with the control group,it showed significantly higher functional activity in left hippocampus,left middle temporal gyrus,bilateral putamen,left inferior frontal gyrus,etc.in the Baduanjin group;while left thalamus showed significantly higher functional activity in the opposite contrast.Compaired with the control group,the brisk walking group showed significantly higher functional activity in left inferior frontal gyrus,bilateral precentral gyrus,left middle temporal gyrus,bilateral precuneus and so on;while bilateral thalamus and caudate showed significantly higher functional activity in the opposite contrast.We also found that,compaired with brisk walking group,the brain regions in Baduanjin group showed significantly higher functional activity were as follows:bilateral putamen and caudate,right thalamus,right superior frontal gyrus,right middle frontal gyrus,etc.;left inferior frontal gyrus(orbital part),bilateral precentral gyrus and so on.After correlation analysis of cognitive function perfomance and the peak T value extracted from the above brain regions,we found that it showed significant correlation between the MoCA score and right putamen,the abstract thinking score and left temporal gyrus,the score of counting from 1 to 100 and left putamen.Conclusions:1.Regular Baduanjin exercise for 6 months could significantly improve the global cognitive function,memory function and processing speed of MCI patients.Besides,the effects may be better than brisk walking exercise.2.The 6-month Baduanjin exerc:ise significantly increased the functional activity of bilateral putamen,left hippocampus,left inferior frontal gyrus,etc.,and it may improve the global cognitive function and memory through this potential DMN mechanism in MCI patients.