A whole-head 64-channel SQUID magnetometer of SNS (Superconductor/ Normal metal / Superconductor) junctions has been constructed to be operated in a superconducting magnetic shield of Bi(Pb)SrCaCuOx demonstrating the sensitivity of 5 femto Tesla in our laboratory only 10 meter far from both an elevator and power transformer banks. Signal-to-noise ratio of data in neuromagnetic measurements is exellent because a SQUID of SNS junctions has a smaller telegraph noise than that of SIS tunnel junctions and because shielding factors of the superconducting magnetic shield does not reduce even at as low frequencies as 0.05 Hz unlike that of Permalloy shield room. A movie is made to compare the evoked current dipole in the MEG data with the MRI images. [References: 1]
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