A technique for sequential measurements of DC neuromagnetic fields.

Magnetoencephalography (MEG) has the capability of detecting DC neuromagnetic fields which might arise from migraine, stroke, head trauma, etc. However, such fields are not readily measured in serial fashion for technical reasons, including arbitrary neuromagnetometer baselines, residual DC fields which vary from place to place inside conventional magnetically shielded rooms, and especially the high sensitivity of such measurements to small changes in distance between the probe and head. A technique is described to carry out such measurements by raising and lowering the subject under the probe and calibrating the DC shift against the amplitude of spontaneous activity.