Masaki Sekino1,
2, Tomoaki Takewa1, Dongmin Kim1, 2,
Yusuke Inoue1, 2, Hiroyuki Ohsaki1
1Department
of Electrical Engineering and Information Systems, Graduate School of
Engineering, The University of Tokyo, Bunkyo-ku, Tokyo, Japan; 2Exploratory
Research for Advanced Technology, Japan Science and Technology Agency,
Bunkyo-ku, Tokyo, Japan
Detection of weak magnetic fields arising from neuronal electrical activities using MRI is an attractive but challenging topic in functional MRI. We measured three-dimensional distribution of local field potentials in the rat somatosensory cortex using a 16-channel microelectrode array with a spatial resolution of 0.3 mm. Local distributions of electric current and magnetic field were calculated from the measured potentials. The resulting field magnitude of 2.8x10-12 T was comparable to the theoretical sensitivity limit of MRI.