Abstract
Electrical activities develop simultaneously with the establishment of magnetic fields following Biot-Savart's law. Excitation of cerebral neurons causes the development of electrical activities, and thereby produces magnetic fields. The term “magnetoencephalography (MEG)” refers to the detection and study of these magnetic fields. It is therefore possible to estimate accurately the origins of the magnetic fields, i. e. deep foci of electrical activities, from the outside of the scalp. This report describes the principle of magnetoencephalography, the recording method, and the estimation of intracerebral localization for rolandic discharges in benign childhood epilepsy with centrotemporal spikes.
