Effects of Action Observation Training on EEG in Patients with Chronic Stroke

Purpose: This study examined the effects of action observation training (AOT) on electroencephalographic (EEG) activity in patients with chronic stroke. Methods: The participants were assigned randomly to one of three groups: an action observation training with activity (AOT) group (n=8), an action observation only (AO) group (n=8), and a control (C) group (n=8). All groups received conventional physiotherapy consisting of five 60-minute sessions per week for six weeks. In addition, the AOT and AO groups participated in AOT and AO sessions, respectively, for three 30-minute sessions per week over six weeks. Results: The AOT group showed significant improvements in the EEG activity. Specifically, alpha wave activity increased, and the beta wave activity decreased significantly in the prefrontal (Fp1 and Fp2) and temporal (T3 and T4) regions (p<0.05). In the AO group, beta wave activity decreased significantly in the prefrontal (Fp1) region, and in the C group, the beta wave activity decreased significantly in the temporal (T3) region (p<0.05). An analysis of the between-group differences using the changes in relative alpha wave activity revealed significant differences among the three groups (p<0.05). Post hoc comparisons revealed significant differences between the AOT and control groups in the prefrontal (Fp1, Fp2) and temporal (T3, T4) regions. An analysis of the between-group differences using the changes in relative beta wave activity showed no significant differences among the three groups. Conclusion: These findings suggest that action observation training may positively influence the regulation of cortical activity in the prefrontal and temporal regions in individuals with chronic stroke.