An assembly of devices used to non-invasively detect, measure, and display bio-magnetic signals produced by electrically-active cortical brain tissue, and that provide diagnostic information about the location of the active tissue responsible for cognitive brain functions relative to the surrounding brain anatomy [magnetoencephalography (MEG)]. It typically consists of a movable gantry, a patient table, a dewar [vessel containing liquid helium (He)], dedicated software, and a superconducting quantum interference device (SQUID) sensor array that measures the magnetic fields created by electrical current flowing with neurons. It is typically sited within a magnetically-shielded room (MSR).