Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1997-8-29
pubmed:abstractText
Cortical areas responsive to somatosensory inputs were assessed by recording somatosensory evoked magnetic fields (SEF) to electrical stimulation of the left median nerve at wrist, using a 122-SQUID neuromagnetometer in various conditions of stimulus rate, attentional demand and detection task. Source modelling combined with magnetic resonance imaging (MRI) allowed localisation of six SEF sources on the outer aspect of the hemispheres located respectively: (1) in the posterior bank of the rolandic fissure (area SI), the upper bank of the sylvian fissure (parietal opercular area SII) and the banks of the intraparietal fissure contralateral to stimulation, (2) in the SII area ipsilateral to stimulation and (3) in the mid-frontal or inferior frontal gyri on both sides. All source areas were found to be simultaneously active at 70-140 ms after the stimulus, the SI source was the only one active already at 20-60 ms. The observed activation timing suggests that somatosensory input from SI is processed to higher-order areas through serial feedforward projections. However the long-lasting activations of all sources and their overlap in time is also compatible with a top-down control mediated via backward projections.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0013-4694
pubmed:author
pubmed:issnType
Print
pubmed:volume
104
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
281-9
pubmed:dateRevised
2008-9-9
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Activation of a distributed somatosensory cortical network in the human brain. A dipole modelling study of magnetic fields evoked by median nerve stimulation. Part I: Location and activation timing of SEF sources.
pubmed:affiliation
Department of Functional Neurology and Epileptology, Hôpital Neurologique, Lyon, France. mauguier@cismsun.univ-lyonl.fr
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't