title: Cerebral magnetic fields to lingual stimulation.
abstract: We recorded cerebral magnetic fields to electric stimulation of the tongue in 7 healthy adults. The two main deflections of the response peaked around 55 msec (P55m) and 140 msec (N140m). During both of them the magnetic field pattern, determined with a 7- or 24-channel SQUID magnetometer, suggested a dipolar current source. The topography of P55m can be explained by a tangential dipole at the first somatosensory cortex (SI) in the posterior wall of the central sulcus. The equivalent source of N140m is, on average, about 1 cm lateral to the source of P55m. The reported method allows non-invasive determination of the cortical tongue representation area.
authors.affiliation: Low Temperature Laboratory, Helsinki University of Technology, Espoo, Finland.
authors.forename: J
authors.initials: J
authors.lastname: Karhu
authors.forename: R
authors.initials: R
authors.lastname: Hari
authors.forename: S T
authors.initials: ST
authors.lastname: Lu
authors.forename: R
authors.initials: R
authors.lastname: Paetau
authors.forename: J
authors.initials: J
authors.lastname: Rif
mesh_terms: D000328:Adult; D001921:Brain / Q000502:physiology*; D004558:Electric Stimulation; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D008475:Median Nerve / Q000502:physiology; D011930:Reaction Time; D012016:Reference Values; D014059:Tongue / Q000502:physiology*