Linked Life Data

9121498

Source:http://linkedlifedata.com/resource/pubmed/id/9121498

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1997-4-24
pubmed:abstractText
We studied the silent period (SP) that interrupts voluntary electromyographic activity (EMG) in facial muscles, after transcranial magnetic stimulation (TMS), in normal subjects. High-intensity magnetic stimulation with a 12-cm round coil centered at the vertex induced a long-lasting SP (215 ms), whereas supramaximal stimulation of the facial nerve only induced a short (< 20 ms) and incomplete EMG suppression, and cutaneous stimuli had no inhibitory effect at all. Cutaneous trigeminal stimulation delivered after TMS evoked blink-like reflexes, showing that facial motoneurons were not inhibited during the SP. Simultaneous recordings from perioral muscles (large cortical representation) and from orbicularis oculi and masseter muscles (small cortical representation) showed SPs of identical duration. Focal stimuli with a figure-of-eight coil showed that positioning of the coil was critical and that the optimal scalp sites for evoking the largest motor potentials and longest SPs coincided. Low-intensity stimulation occasionally elicited short SPs without a preceding motor potential. We conclude that the SP induced in facial muscles by TMS results from the excitation of cortical inhibitory interneurons surrounding the upper motoneurons.
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0148-639X
pubmed:author
pubmed:issnType
Print
pubmed:volume
20
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
418-24
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Cortical mechanisms mediating the inhibitory period after magnetic stimulation of the facial motor area.
pubmed:affiliation
Department of Neurological Sciences, University of Rome La Sapienza, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't