Brain Control Mechanism Of College Students’ Motor Imagery With Different Physical Activity Levels

Objective: To explore the differences of ERD / ERS phenomenon,brain activation level,and pattern recognition in sports imagination of college students with different levels of physical activity.Methods: According to the Chinese version of the international physical activity questionnaire(IPAQ),10 people were selected according to the criteria of physical activity≥ 3 d / W and total physical activity ≥ 3500 met-min / W per week to form a high physical activity group;According to the standard of total physical activity < 600 met min/ W per week,10 people were selected to form a low-level physical activity group.The left and right EEG signals of each subject were pre-processed by ICA.When imagining the subject’s movement α And β ERD / ERS time-frequency power feature extraction and brain topographic map feature extraction were carried out for rhythm,and CSP feature extraction and SVM pattern recognition and classification were carried out for Motor imagery EEG signals.Result:(1)C3 and C4 channels of left and right hand movement imagination of college students with different physical activity levels α And β There was obvious ERD/ERS phenomenon in the rhythm.The duration of bilateral ERD/ERS in the high physical activity group was significantly lower than that in the low physical activity group;Right hand movement imagination,α And β The power value of rhythm in C3 and C4 channels was significantly lower than that in low physical activity group;Left hand C3(M=-0.163,SD= 1.061),left hand C4(M=-0.106,SD= 0.927),right hand C3(M=-0.093,SD=0.885),right hand C4(M=-0.111,SD= 0.95)in high physical activity group and left hand C3(M=-0.635,SD= 11.635),left hand C4(M=-0.437,SD= 2.036),right hand C3(M=-0.289,SD= 1.561)in low physical activity group Right hand C4(M=-0.25,SD= 1.506)had a very significant difference(P < 0.01).(2)The power value of each channel in the high physical activity group was lower than that in the low physical activity group,and the main effect of the group was significant(p<0.001);In the high physical activity group,the concentration of the contralateral ERD power value was stronger and the hemispheric main effect was significant(p<0.001);The power value of contralateral ERD phenomenon in low physical activity group showed more scattered and concentrated.(3)The main effect of high and low physical activity group was significant(p<0.001),and high physical activity group α And β On the contralateral side of the rhythm,the ERD phenomenon was significant,the hemispheric main effect was significant(p<0.001),the power concentration of ERD phenomenon was higher,the main effect of brain region was significant(p<0.01),the interaction between brain region and group was significant(p<0.05),the interaction between brain region and hemisphere was significant(p<0.001),and the group effect of frontal central region(p<0.001),central parietal region(p<0.001)and parietal region(p<0.001)in the left hemisphere was significant.(4)When the students grew up in different physical activities,the average correct rate of the low-level physical activity group(83.2% ± 2.9)was higher than that of the high-level physical activity group(56.9% ± 8.4)(χ2=16.06,P<0.05)Conclusion:(1)Long-time physical activity will enhance the Motor imagery function of the dominant hand,reduce the brain nerve power value of Motor imagery,and reduce the resource consumption of the contralateral hemisphere when the dominant hand grasps the Motor imagery.(2)Long-time physical activity will regulate cognitive processing function,strengthen the lateralization advantage of the cerebral cortex,improve the automation level of dominant hand grasping,enhance the function of the cerebral cortex,network information flow,and brain plasticity.(3)High physical activity level will reduce the performance of EEG features,affecting the accuracy of CSP feature extraction and SVM pattern recognition classification.