Differences in Brain Waves of Normal Persons and Stroke Patients during Action Observation and Motor Imagery.

[Purpose] The purpose of this study was to examine the changes in brain waves between action observation and motor imagery of stroke patients and normal subjects, and to compare them. [Methods] Twelve stroke patients and twelve normal persons participated in this research. Each group executed action observation and the motor imagery training for 3 minutes, and before and during each intervention the brain waves were measured for 3 minutes, and the relative alpha power and relative beta power analyzed. [Results] Both normal persons and stroke patients showed significant differences in relative alpha power during action observation, but no significant difference in relative alpha power was found during motor imagery. The relative beta power increased similarly in both groups but it was more significantly different during action observation than during motor imagery. [Conclusion] Both action observation and motor imagery can be used as a therapeutic method for motor learning. However, action observation induces stronger cognitive activity, so for the stroke patients who have difficulty with fine motor representation, action observation might be a more effective therapy.