[1] Tottori Univ, Fac Med, Inst Neurol Sci, Div Neurol, Yonago, Tottori 6838504, Japan
[2] Tottori Univ, Fac Med, Inst Life Sci, Dept Neurobiol, Yonago, Tottori 6838504, Japan
[3] Tottori Univ, Fac Educ, Dept Home Econ, Tottori 680, Japan
[4] Tohoku Univ, Sch Med, Dept Geriatr & Resp Med, Sendai, Miyagi 980, Japan