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Note: Unshielded bilateral magnetoencephalography system using two-dimensional gradiometers
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1.
1.M. S. Hämäläinen, R. Hari, R. J. Ilmoniemi, J. Knuutila, and O. V. Lounasmaa, Rev. Mod. Phys. 65, 413 (1993).
http://dx.doi.org/10.1103/RevModPhys.65.413
2.
2.The SQUID Handbook, edited by J. Clarke and A. I. Braginski (Wiley-VCH, Weinheim, Germany, 2004), Vol. II.
3.
3.J. E. Zimmerman, J. Appl. Phys. 48, 702 (1977).
http://dx.doi.org/10.1063/1.323659
4.
4.Y. P. Ma and J. P. Wikswo, Jr., Rev. Sci. Instrum. 62, 2654 (1991).
http://dx.doi.org/10.1063/1.1142195
5.
5.D. T. Wehner, M. S. Hämäläinen, M. Mody, and S. P. Ahlfors, Neuroimage 40, 541 (2008).
http://dx.doi.org/10.1016/j.neuroimage.2007.12.026
6.
6.E. Pekkonen, I. P. Jääskeläinen, M. Hietanen, M. Huotilainen, R. Näätänen, R. J. Ilmoniemi, and T. Erkinjuntti, Clin. Neurophysiol. 110, 1942 (1999).
http://dx.doi.org/10.1016/S1388-2457(99)00153-4
7.
7.H. Oe, A. Kandori, T. Miyashita, K. Ogata, N. Yamada, K. Tsukada, K. Miyashita, S. Sakoda, and H. Naritomi, Proceedings of ISBET 2004: Frontiers in Human Brain Topology, International Congress Series, 2004, Vol. 1270, p. 117.
8.
8.E. Pekkonen, D. Osipova, O. Sauna-Aho, and M. Arvio, Neuroimage 35, 1547 (2007).
http://dx.doi.org/10.1016/j.neuroimage.2007.01.036
9.
9.E. Pekkonen, J. Hirvonen, I. P. Jääskeläinen, S. Kaakkola, and J. Huttunen, Neuroimage 14, 376 (2001).
http://dx.doi.org/10.1006/nimg.2001.0805
10.
10.E. Pekkonen, I. P. Jääskeläinen, S. Kaakkola, and J. Ahveninen, Neuroimage 27, 387 (2005).
http://dx.doi.org/10.1016/j.neuroimage.2005.04.018
11.
11.Y. Seki and A. Kandori, Jpn. J. Appl. Phys. 46, 3397 (2007).
http://dx.doi.org/10.1143/JJAP.46.3397
12.
12.Y. Seki, A. Kandori, Y. Kumagai, M. Ohnuma, A. Ishiyama, T. Ishii, Y. Nakamura, H. Horigome, and T. Chiba, IEEE Trans. Appl. Supercond. 19, 857 (2009).
http://dx.doi.org/10.1109/TASC.2009.2019032
13.
13.Y. Seki, A. Kandori, Y. Kumagai, M. Ohnuma, A. Ishiyama, T. Ishii, Y. Nakamura, H. Horigome, and T. Chiba, Rev. Sci. Instrum. 79, 036106 (2008).
http://dx.doi.org/10.1063/1.2897588
14.
14.C. Pantev, B. Ross, P. Berg, T. Elbert, and B. Rockstroh, Audiol. Neuro-Otol. 3, 183 (1998).
http://dx.doi.org/10.1159/000013789
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/content/aip/journal/rsi/81/9/10.1063/1.3482154
2010-09-20
2014-12-21

Abstract

Magnetoencephalography(MEG) noninvasively measures neuronal activity with high temporal resolution. The aim of this study was to develop a new type of MEG system that can measure bilateral MEG waveforms without a magnetically shielded room, which is an obstacle to reducing both the cost and size of an MEG system. An unshielded bilateral MEG system was developed using four two-dimensional (2D) gradiometers and two symmetric cryostats. The 2D gradiometer, which is based on a low-superconducting quantum interference device and wire-wound pickup coil detects a magnetic-field gradient in two orthogonal directions, or , and reduces environmental magnetic-field noise by more than 50 dB. The cryostats can be symmetrically positioned in three directions: vertical, horizontal, and rotational. This makes it possible to detect bilateral neuronal activity in the cerebral cortex simultaneously. Bilateral auditory-evoked fields (AEF) of 18 elderly subjects were measured in an unshielded hospital environment using the MEG system. As a result, both the ipsilateral and the contralateral AEF component N100m, which is the magnetic counterpart of electric N100 in electroencephalography and appears about 100 ms after the onset of an auditory stimulus, were successfully detected for all the subjects. Moreover, the ipsilateral P50m and the contralateral P50m were also detected for 12 (67%) and 16 (89%) subjects, respectively. Experimental results demonstrate that the unshielded bilateral MEG system can detect MEG waveforms, which are associated with brain dysfunction such as epilepsy, Alzheimer’s disease, and Down syndrome.

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Scitation: Note: Unshielded bilateral magnetoencephalography system using two-dimensional gradiometers
http://aip.metastore.ingenta.com/content/aip/journal/rsi/81/9/10.1063/1.3482154
10.1063/1.3482154
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