Functional Connectivity Of The Task State And ReHo Of The Resting-state In Brain M1FMRI Study On Stroke Patients

Objective:Combining Task state to resting state fMRI were performed to observe the change of activity strength between bilateral M1, and analyze the changes of functional connectivity of task state and ReHo of resting state on chronic stroke patients. It explained that the feature of the M1function change and the role of motor recovery afte stroke. It provided theoretical basis to explore the mechanism on motor recovery after stroke.Methods:Single lesion located in basal ganglia and more than six months of28stroke patients (18males and10females) and25normal subjects (14males and11females) were recruited in this study. GE3.0T HDX MR Scanner was used to obtain high resolutions anatomy images and fMRI data in resting and task state, which was block-designed fMRI with fisting of each hand. Freesuefer V.5.1.0was used to calculate M1probability maps about all subjects as M1mask. Matlab, SPM8and REST softwares were used to process fMRI data about task state and resting state. Using GLM with age and gender as the nuisance covariates and M1as mask to analyze the two sample t-test, compared the difference of M1activity between stroke patients and normal subjects; extraction of the activity differences regions as ROI, for the voxel-vise functional connectivity analysis, compared the difference of functional connectivity between the two groups; and compared the ROI ReHo between the two groups.Results:To compare the differences of M1activity between stroke patients and normal subjects, it found that the affected hemisphere M1activated enhancement, the unaffected hemisphere M1in stroke group activated weaken (P<0.05); ROI-based functional connectivity analysis, it found that higher functional connectivity with the bilateral supplementary motor areas and precentral gyruses. On the contrary, functional connectivity with cerebellum, insular lobes, partial frontal and temporal and parietal cortex were decreased (P<0.05); the ReHo in stroke group was higher than normal subjects (P<0.05)Conclusion:1、 M1increased activity in the affected hemisphere and decreased in unaffected hemisphere on chronic basal ganglia stroke patients, wich reflected the cortex compensatory function;2、 Functional connectivity increased between bilateral M1and motor related brain regions,such as SMA and precentral gyrus, which reflected that motor recovery was improved as regional compensatory mechanism;3、 ReHo of M1increased in affected hemisphere,which explained that M1the synchronicity of neurons activities increased and information transmission and processing efficiency were improved,as local compensatory mechanism;4、 It is an important tool that explore the mechanisms of motor recovery with the combination of task state and resting state fMRI after stroke.