Comparative Study On The Characteristics Of EEG And SEMG In Active Or Passive Arm Actions

Dexterity of arm (wrist, upper limb) actions (making a fist, palming, bending thearm) intuitively reflects the system control functions about neural activity of cerebralcortex motor area with related bone and muscle and is also a simple method toscreening Stroke sequela. Cerebral apoplexy commonly known as stroke, which is adisease of rapid loss brain function caused by brian blood supply interrupted ordisordered. It is proved by clinical practice that repetitive passive body exercisetraining can activate the human nervous system autonomous motion network andpromote the nerve cell activity and functional substitutes of cerebral cortex motor areaand improve or be part of rebuilding its voluntary movement. But the principles ofabove medical treatments are not clear. Therefor it has important clinical value tounderstand the function of motor pathway and provide a scientific basis fordeveloping the new technology of stroke rehabilitation treatment that study humanelectroencephalography (EEG) and surface electromyography (sEMG) during activelimbs movement and compare its signal characteristics with the EEG and sEMGduring passive limbs movements and discuss their different characteristics and effectsin activating the brain motor cortex nerves and peripheral nerves and muscles.The main works completed by this paper are: two experimental paradigms ofactive and passive wrist flexions were designed and a complete set of hardware andsoftware (The LabVIEW software, DAQ acquisition card, and visual feedback system)for supporting the experiments were set up. Then9testee (4male,5female) wererecruited to perform these experiments of active and passive wrist flexions and theEEG and sEMG data of testee were collected at the same time. After then, thecharacteristics of EEG and sEMG signals in active or passive flexing wrist actionswere compared in time domain, frequency domain and time-frequency domainseparately by signal processing tools and the different features and effects of thesetwo action patterns in the activation of brain motor cortex nerves and the productionof peripheral nerves and muscles were investigated. Finally, we used Morlet wavelettransform and coherence assessment methods to study the time–frequency domaincharacteristics of EEG and sEMG and their intrinsic relationship during autonomyand passive action paradigms.The main investigated results show that the changes of EEG in time–frequencydomain and the average amplitude envelope of EMG and its power spectrum in the passive flexing wrist action were all similar to the changes of EEG and EMG inthe active flexing wrist action. It also shows that like the active action, the passivebody movements may induce the phenomenon of event related de-synchronization(ERD), and it proved that the cerebral cortex motor area and the peripheral nervoussystem can be activated and make connections by passive action too. Forther more, itshows that the coherence properties of EEG and sEMG were similar during passiveand active flexor wrist and the coherence amplitude between EMG of flexor and EEGsignal at C3channel in passive action was more stronger than that of active action. Itmay be aroused by the imaginative action induced by the forced movement which canenhance the activity degree of brain neurons.Up to now, there was seldom that study on the relativity of EEG and sEMGduring repetitive passive arm movement. The results of this paper may give somesupports for the clinical practices of repeated passive limb movement rehabilitationtraining and provide the scientific basis for related researches.