Premium
Observation of changes in neural activity due to the static magnetic field of an MRI scanner
Author(s) -
Toyomaki Atsuhito,
Yamamoto Toru
Publication year - 2007
Publication title -
journal of magnetic resonance imaging
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.563
H-Index - 160
eISSN - 1522-2586
pISSN - 1053-1807
DOI - 10.1002/jmri.21151
Subject(s) - electroencephalography , magnetostatics , magnetic field , brain activity and meditation , scanner , arousal , magnetic resonance imaging , nuclear magnetic resonance , physics , acoustics , neuroscience , computer science , psychology , medicine , artificial intelligence , quantum mechanics , radiology
Purpose To clarify whether a strong static magnetic field affects brain activity such as arousal level. Materials and Methods We compared the electroencephalography (EEG) inside an MRI scanner in the presence/absence of the static magnetic field in two different arousal levels of task and rest conditions. Cardiac‐related pulsations of head and blood flow induce an electric voltage at each EEG electrode in a static magnetic field. This induced voltage overlaps with the intrinsic EEG signal and becomes a large confounding factor. To extract the information of the intrinsic EEG from the contaminated EEG data measured in a static magnetic field, we developed a new analysis method. Results No significant difference was observed in the intrinsic EEG in the absence of a magnetic field, whereas in the presence of the static magnetic field, the theta frequency band of the intrinsic EEG increased, especially during the task condition, but other frequency bands did not change. Conclusion Our results demonstrate that a static magnetic field affects brain activity. J. Magn. Reson. Imaging 2007;26:1216–1221. © 2007 Wiley‐Liss, Inc.