1. Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
2. Department of Neurology, The Second Hospital of Jilin University, Jilin, China.
3. Department of Rehabilitation, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
4. China National Clinical Research Center for Neurological Diseases, Beijing Tiantan Hospital, Capital Medical University, Beijing, China. Memory and Aging Center, Department of Neurology, University of California, San Francisco, San Francisco, California, USA.