1. Neurorehabilitation Research Center, Kio University, Nara, Japan
2. Intelligent Systems and Informatics Laboratory, Department of Mechano-Informatics, Graduate School of Information Science and Technology, The University of Tokyo, Tokyo, Japan
3. Center of Medical Science, Ibaraki Prefectural University of Health Science, Tokyo, Japan
4. Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan
5. Department of Pain and Palliative Medicine, The University of Tokyo Hospital, Tokyo, Japan