The investigators propose a 3-year randomized controlled trial to (1) investigate the short- and long-term treatment efficacy of AOIE, action observation alone, versus customary rehabilitation on clinical outcomes of patients with subacute stroke, (2) examine the neural mechanisms and activation changes after the 3 interventions by using an advanced brain imaging technique, magnetoencephalography (MEG), (3) determine the correlations between neural activation changes and clinical outcomes, and (4) identify who are the good responders to the AOIE therapy. An estimated total of 96 patients with subacute stroke will be recruited in this study. All participants will be randomly assigned to receive 1 of the 3 interventions for 3 weeks (a total of 15 sessions). Clinical outcome measures will be conducted at baseline, immediately after treatment (3 weeks), and at 3 months follow-up. The MEG assessment will be conducted at baseline and immediately after treatment (3 weeks). For the MEG study, The investigators anticipate to enroll 12 to 15 patients in each group to complete neuroimaging evaluation because of the specific eligibility criteria and high costs of MEG. The patients can still participate in the study, receiving rehabilitation therapy and clinical evaluations, even if the participants will not be included in the MEG study.