Magnetoencephalography with an Array of Squid Sensors

摘要

A novel installation was developed for unshielded measurements of the neuromagnetic field near the scape with a cryogenic system incorporating nine SQUID sensors in a single dewar. Five dc-SQUIDs measure the field of interest sensed by a radial array of five detection coils, while four rf-SQUIDs monitor three components of the ambient field and the axial gradient. The latter are applied to electronic cancellation of background noise. The dewar is mounted in a scanning device for rapid and accurate positioning about the head. This system provides major advantages over conventional single-sensor systems.