[1] Sungkyunkwan Univ, Grad Sch Clin Nursing Sci, Seoul, South Korea
[2] Samsung Med Ctr, Clin Nursing Res Ctr, Seoul, South Korea
[3] Univ Southern Calif, Keck Sch Med, Stevens Neuroimaging & Informat Inst, Los Angeles, CA USA
[4] Sungkyunkwan Univ, Dept Neurol, Seoul, South Korea
[5] Samsung Med Ctr, Dept Neurol, Neurosci Ctr, Seoul, South Korea