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Construction and Operation of a 37-channel Hemispherical Magnetoencephalogram System  

이용호 (한국표준과학연구원 초전도그룹)
김진목 (한국표준과학연구원 초전도그룹)
권혁찬 (한국표준과학연구원 초전도그룹)
김기웅 (한국표준과학연구원 초전도그룹)
박용기 (한국표준과학연구원 초전도그룹)
강찬석 (고려대학교 물리학과)
이순걸 (고려대학교 물리학과)
Publication Information
Journal of Biomedical Engineering Research / v.24, no.3, 2003 , pp. 159-165 More about this Journal
Abstract
We developed a 37-channel magnetoencephalogram (MEG) measurement system based on low-noise superconducting quantum interference device (SQUID) magnetometets, and operated the system to measure MEG signals. By using double relaxation oscillation SQUIDs with high flux-4o-voltage transfers, the SQUID outputs could be measured directly by room temperature preamplifiers and compact readout circuits were used for SQUID operation. The average field noise level of the magnetometers is about 3 fT/√Hz in the white region, low enough for MEG measurements when operated inside a magnetically shielded room. The 37 magnetometers were distributed on a hemispherical surface haying a radius of 125 mm. In addition to the 37 sensing channels. 11 reference channels were installed to pickup external noise and to form software gradiometers. A low-noise liquid helium dewar was fabricated with a liquid capacity of 30 L and boil-off rate of 4 L/d. The signal processing software consists of digital filtering, software gradiometer, isofield mapping and source localization. By using the developed system, we measured auditory-evoked fields and localized the current dipoles, demonstrating the effectiveness of the system.
Keywords
Magnetoencephalogram; Auditory-evoked field; SQUID magnetometer;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
연도 인용수 순위
1 A Multichannel SQUID Magnetometer System Based on Double Relaxation Oscillation SQUIDs /
[ Y.H.Lee;H.Kwon;J.M.Kim;C.S.Kang;K.Kim;I.S.Kim;Y.K.Park;S.G.Lee ] / IEEE Trans. Appl. Supercond
2 Development of MEG measurement using SQUID /
[ Y.H.Lee(et al.) ] / KRISS Research Report, KRISS/IR 2000-094
3 Magnetoencephaography theory, instrumentation, and applications to noninavasive studies of the working human brain /
[ M.Hamalainen(et al.) ] / Rev. Mod. Phys.   ScienceOn
4 Localization error of a 150-channel whole-cortex magnetoencephalography system /
[ J.W.Lee;Y.H.Lee;S.C.Jun;H.C.Kwon ] / J. Kor. Phys. Soc.   과학기술학회마을
5 Recent Law Temperature SQUID Developments /
[ D.Drug. ] / IEEE Trans. Appl. Supercond.   ScienceOn
6 /
[] / 13th Int'l Conf. Biomagnetism
7 /
[ J.Vrba ] / SQUID Sensors : Fundamentals, Fabrication and Applications, Dordrecht
8 /
[] / 12th Int'l Conf. Biomagnetism
9 Programmatic Sequences for the Automatic Adjustment of Double Relaxation Oscillation SQUID Sensors /
[ K.Kim;Y.H.Lee;H.Kwon;J.M.Kim;C.S.Kang;I.S.Kim;Y.K.Park ] / Prog. Supercond.   과학기술학회마을
10 Localization accuracy of single current dipoles from tangentai components of auditory evoked fields. /
[ H.Kwon;Y.H.Lee;J.M.Kim;Y.K.Park;S.Kuriki ] / Phys. Med. Bio.   ScienceOn
11 Correction in the Principal Component Elimination Method for Excluding Correlated Noises in Neuromagnetic Evoked Field Measurements /
[ K.Kim;Y.H.Lee;H.Kwon;J.M.Kim;C.S.Kang;Y.K.Park;I.S.Kim ] / IEEE Trans. Biomed. Eng. Submitted
12 Multichannel applications of double relaxation oscillation SQUIDs /
[ Y.H.Lee;H.C.Kwon;J.M.Kim;Y.K.Park ] / Supercond. Sci. Technol.   ScienceOn
13 Construction an Performance of Magnetically Shielded Room for Biomagnetic Applications /
[ Y.H.Lee;H.C.Kwon;J.M.Kim;C.M.Lim;S.K.Lee;Y.K.Park;J.C.Park ] / J. Kor. Mag. Soc.
14 /
[] / ASA Program
15 (Double)relaxation oscillation SQUIDs with high flux-to-voltage transfer: Simulations and experiments /
[ D.J.Adelerhof;H.Nijstad;F.Flokstra;H.Rogalla ] / J. Appl. Phys.   ScienceOn