Research On The Analysis Method Of Brain Computer Network For The Execution And Imagination Of Finger Movement

Motor imagination is one of the classic paradigms of brain computer interface.In recent years,because of its role in promoting neural plasticity,it has been widely concerned as a new method in the field of rehabilitation of motor function after stroke,and plays an important role in the rehabilitation of the sequelae of motor dysfunction after stroke.More than 60% of stroke patients have the sequelae of loss of limb motor function,especially the occurrence of hand motor dysfunction.In this paper,we designed a new experimental paradigm to collect EEG signals during finger movement and imagination,and studied the brain computer network related to finger movement,that is,the connection between brain regions related to movement.The main work of this paper is as follows:1.This paper designs a new experimental paradigm of finger movement execution and movement imagination.There are 11 healthy subjects participating in the experiment.Each subject carries out two experiments of left hand and right hand respectively.Each experiment collects 30 finger movements in two scenes of movement execution and movement imagination twice,a total of 60 trails.2.In order to solve the problem that the traditional ICA method needs a large amount of computation and may not be able to fully remove the artifacts or lose the information of EEG data,a new method of removing the artifacts is proposed,which combines PCA,jade and ARX.The experimental results show that compared with jade algorithm,the new method can better remove the artifacts in EEG signal.3.Using the Granger causality analysis method,the bilateral premotor area(PMA),the contralateral primary motor area(MA)and the bilateral primary sensory area(SA),which are directly related to motor function,are selected as network nodes to analyze and compare the Granger causality connectivity and connection strength between these areas.The experimental results show that the largest number of Granger causality tracks is 37 ± 7.3,35.5 ± 8.8,36.3 ± 10.3,39.2 ± 9.0,and the smallest coefficient of Granger causality is 9.1 ± 3.2,10.9 ± 3.7,13.2 ± 0.6,13.4 ± 0.6.Further analysis found that the Granger causality and connection strength between brain related motor areas were related to the task hand and handedness of the subjects.The brain network map of right hand finger task and left hand finger task was basically mirror image,but the closed circuit of right hand finger task was more;and the brain network map of finger movement was more effective than that of fingermovement imagination Connect.These results indicate that in the rehabilitation of motor function after stroke,the analysis index of Granger causality brain network is expected to become an effective feature of motor function evaluation,and patients with left and right handedness should also try more personalized motor function recovery strategies.