Investigating the Impact of Electromyographic Biofeedback on Improvement of Hand Grasp Function and EEG Signal Dynamics of HemiplegicStroke Patients

After cardiovascular disease and cancers, stroke is the third leading cause of death in the world and the second most common death reason in Iran. Recovery through pharmaceutical and physiotherapy methods is very time-consuming and in some cases, it is not achievable. Hence, an effective, low-cost, and noninvasive treatment is very important for stroke patients. One of these applied techniques is biofeedback therapy.Materials and Methods: The purpose of this study was to investigate the effect of electromyography biofeedback therapy to improve the hand grasping function of stroke patients. In addition, time-frequency features of electroencephalography (EEG) signals of patients wereinvestigated in all frequency bands. Results: Results indicate that after the implementation of the biofeedback intervention, the ability of patients to control the position of the fingers has improved significantly and the phenomenon of joint locking of fingers is no longeroccurred. In addition, it was observed that there was a significant difference between the time and frequency characteristics of brain signals before and after the biofeedback intervention. But the change in the value of the features in the Beta and Gamma frequency bands hasbeen higher than in other frequency bands. These results could mean the activation of some neuronal networks that were deactivated by the stroke. In fact, these neural networks were activated by biofeedback-based exercise, and consequently, the processes of motor cortexcommands have been restored. Conclusion: In this research, the effectiveness of an intervention method was studied based on lectromyography biofeedback to improve fingers control in chronic stroke patients. Overall, the results show that the motor exercisebased on bio feedback electromyography could lead to improve the motor abilities and controllability of the patients’ hands.