  A seven-channel system capable of performing both magnetoencephalography
(MEG) and ultra-low-field magnetic resonance imaging (ULF MRI) is described.
The system consists of seven second-order SQUID gradiometers with 37 mm
diameter and 60 mm baseline, having magnetic field resolution of 1.2-2.8
fT/rtHz. It also includes four sets of coils for 2-D Fourier imaging with
pre-polarization. The system's MEG performance was demonstrated by measurements
of auditory evoked response. The system was also used to obtain a multi-channel
2-D image of a whole human hand at the measurement field of 46 microtesla with
3 by 3 mm resolution.
