Cortical current source estimation from electroencephalography in combination with near-infrared spectroscopy as a hierarchical prior. - Takatsugu Aihara; Yusuke Takeda; Kotaro Takeda; Wataru Yasuda; Takanori Sato; Yohei Otaka; Takashi Hanakawa; Manabu Honda; Meigen Liu; Mitsuo Kawato; Masa-aki Sato; Rieko Osu (NeuroImage, 2012)