1. Research Team for Promoting Independence of the Elderly; Tokyo Metropolitan Institute of Gerontology; Tokyo Japan
2. Department of Neuropsychiatry, Graduate School of Medicine; The University of Tokyo; Tokyo Japan
3. Department of Neuropsychiatry; Tokyo Metropolitan Matsuzawa Hospital; Tokyo Japan
4. Department of Communication Sciences and Disorders, Faculty of Health and Welfare; Prefectural University of Hiroshima; Hiroshima Japan