Linked Life Data

20943947

Source:http://linkedlifedata.com/resource/pubmed/id/20943947

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2011-1-12
pubmed:abstractText
A suprathreshold pulse of transcranial magnetic stimulation (TMS) delivered to human motor cortex results in a period of long-interval intracortical inhibition (LICI) followed by a briefer period of disinhibition (late cortical disinhibition [LCD]). Short-interval intracortical facilitation (SICF) is mediated by excitatory networks in the motor cortex responsible for the generation of the indirect (I-) wave volleys that are evoked by TMS at a periodicity of about 1.5 ms. Because the excitatory synaptic network responsible for SICF undergoes inhibitory regulation, we hypothesized that SICF will be modulated during periods of inhibition and disinhibition. In particular we were interested to know whether SICF was up-regulated during disinhibition, implying an increase in excitatory synaptic efficacy. We measured SICF, at a paired-pulse interval of 1.5 ms, at various times (100-300 ms) after a suprathreshold priming stimulus (PS) of sufficient strength to evoke LICI and LCD. We found that the strength of SICF was normal during LICI, but was increased during LCD by an average of 64%. SICF onset latency was reduced by one I-wave interval during LCD and was delayed by one I-wave interval during LICI. We conclude that disinhibition, rather than inhibition, modulates the excitatory neuronal networks that underlie SICF, whereas the I-wave targeted is modified by the presence of both inhibition and disinhibition and that there is therefore a dissociation between the strength and site of SICF interaction. The increase in SICF during disinhibition further indicates that this is a promising period to investigate or modulate excitatory synaptic networks while they are less constrained by ongoing levels of inhibition.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1522-1598
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
105
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
100-6
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Inhibitory and disinhibitory effects on I-wave facilitation in motor cortex.
pubmed:affiliation
Centre for Neuromuscular and Neurological Disorders, M518, University of Western Australia, 35 Stirling Highway, Crawley WA 6009, Perth, Australia.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't