Differential Event-Related Spectral Perturbation for Left and Right Elbow Movement for Applications in a Brain-Computer Interface

In the present study, we seek to investigate how the sequence of neuronal events that include stimulus identification, motor planning, and movement execution is implemented in the cortical neural networks, using an experimental paradigm that segregates between preparation and motor activation. For this study, twenty-two right-handed subjects had EEG signals recorded and analyzed. The subjects were divided into two groups. The imagery group performed real right or left forearm movements or the imagination of these movements. The control group performed real movement of the right or left forearm or did not perform any movement (wait condition). The Event-Related Spectral Perturbation (ERSP) in each one of the experimental conditions was compared for the time intervals of preparation, execution, and after-movement end. We observed: (I) mu and beta desynchronizations (ERD) for movement and imagery and not for the wait condition, during preparation and execution periods. (II) The movement ERD is greater than the imagery ERD for both mu and beta bands. (III) Synchronization (ERS) after the movement is finished. (IV) Greater mu ERD during the execution period and beta ERS after the movement ends at the contralateral channels in the movement condition. (V) Gamma ERS after the movement ends for the movement condition, and not for wait. These findings suggest that using signals from the contralateral region of the movement to be executed might impact the accuracy of the control of devices in a brain-computer interface paradigm.