Evoked and Spontaneous Magnetic Activity of the Human Somatosensory Cortex

The generation sites of the somatosensory evoked responses, as well as those of the mu rhythm, have remained controversial. We have, therefore, recorded early somatosensory evoked magnetic fields (SEFs) with a good signal-to-noise ratio. We also measured spontaneous magnetic brain activity over the rolandic area, to find out whether it is possible to detect the magnetic counterpart of the electric mu rhythm and to locate its generators with respect to those of SEFs.