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Magnetoencephalography using high temperature rf SQUIDs.

Y Zhang·Y Tavrin·M Mück·A I Braginski·C Heiden·S Hampson·C Pantev·T Elbert
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Abstract

We have developed high-critical-temperature radio-frequency Super conducting QUantum Interference Devices (SQUIDs) with step-edge grain-boundary Josephson junctions and large flux focusers. These planar devices were fabricated from epitaxial YBa2Cu3O7 films and operated in the magnetometer and first-order gradiometer configurations while immersed in liquid nitrogen. At the temperature of 77K, we have attained a magnetic field resolution for the magnetometer better than 200 fT/Hz1/2 down to less than 1 Hz, i.e., over the low signal frequency range important for medical diagnostics. The results to date show a high promise for biomagnetic diagnostics. For the first time, we recorded the evoked responses from human brains using a high-temperature magnetometer and a first-order electronic gradiometer channel simultaneously. These results were obtained in a magnetically shielded room. An improvement in the magnetic field resolution by another order of magnitude is possible and probable.

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Acoustic StimulationBrainEvoked Potentials, AuditoryHumansMagnetoencephalographyMaleJournal ArticleResearch Support, Non-U.S. Gov't

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Y Zhang, Y Tavrin, M Mück, A I Braginski, C Heiden, S Hampson, C Pantev, T Elbert. 1993. Magnetoencephalography using high temperature rf SQUIDs.. https://doi.org/10.1007/bf01128694

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