Comparison of EEG Changes Induced by Action Execution and Action Observation

PURPOSE: Recent electrophysiological studies have shown that the sensorymotor cortex is activated during both actual action excuted by themselves and observation of action performed by other persons. Observation of action based on mirror neuron system can be used as a cognitive intervention to promote motor learning. The purpose of this study was to investigate the brain activity changes during action observation and action execution using EEG. METHODS: Thirty healthy volunteers participated and were requested to perform hand action and to observe the video of hand action performed by another person. The EEG activity was evaluated by a method which segregated the time-locked for each condition. To compare the differences between action observation and execution, the Mu suppression and the relative band power were analysed. RESULTS: The results showed significant mu suppression during the action observation and execution, but the differences between the two conditions were not observed. The relative band power showed a significant difference during the action observation and execution, but there were no differences between the two conditions. CONCLUSION: These results indicate that action execution and observation involve overlapping neural networks in the sensorymotor cortical areas, proposing positive changes on neurophysiology. We are expected to provide information related to the intervention of cognitive rehabilitation.

The Effects of Functional Electrical Stimulation Combined with Action Observation on Sensorimotor Cortex

PURPOSE: Functional electrical stimulation (FES) is a device that activates the sensorimotor cortex through electrodes attached to the surface of the skin. However, it is difficult to expect positive changes if the recipient is not attentive to the motion. To complement the perceived cognitive limitations of FES, we attempted to investigate the changes of sensorimotor cortex activity by simultaneously providing action observation with FES. METHODS: Electroencephalogram was measured in 28 healthy volunteers. Relative band power over the sensorimotor cortex was analyzed and compared in three conditions: during rest, during FES alone, during action observation with FES. RESULTS: The results showed significant differences in each relative band power. Relative alpha power and relative beta power were the lowest by application of FES combined with action observation, while the relative gamma power was the highest. CONCLUSION: These results suggest that combining FES with observation could be more effective than FES alone in neurorehabilitation.