FIGURE 1.

Training setup. (A) AAT for stroke patients with mild arm paresis, a scenario with the patient, humanoid robot, and supervising staff. (B) ABT for patients with moderate-to-severe arm paresis, a scenario with the patient, humanoid robot, helper, and supervising staff. During nine consecutive sessions over 2 weeks, the therapeutic training (both AAT and ABT) was led by the humanoid robot providing therapeutic interactions as implemented in the digital system E-BRAiN with both training standards, e.g., audio-visual instructions and feedback and individualisation algorithms, e.g., for the feedback content. For safety reasons and to step in if needed, the sessions were accompanied by the supervising staff (sitting in the background). The participants with moderate-to-severe arm paresis receiving the arm basis training cannot necessarily perform the training movements completely by themselves. Since the robot cannot provide physical assistance and serves as a social agent (therapeutic interaction), these participants need a person (“helper”) to provide physical assistance as needed for individual movements.