[1] Duke Univ, Brain Imaging & Anal Ctr, Med Ctr, Durham, NC 27706 USA
[2] Natl Taiwan Univ, Dept Elect Engn, Taipei, Taiwan
[3] Natl Sun Yat Sen Univ, Dept Elect Engn, Kaohsiung, Taiwan
[4] Natl Taiwan Univ Sci & Technol, Dept Elect & Comp Engn, EE-707,43 Sec 4,Keelung Rd, Taipei, Taiwan
[5] Natl Tsing Hua Univ, Dept Biomed Engn & Environm Sci, Hsinchu, Taiwan