PMID- 22596357
OWN - NLM
STAT- MEDLINE
DCOM- 20121128
LR  - 20130410
IS  - 1878-3627 (Electronic)
IS  - 0922-6028 (Linking)
VI  - 30
IP  - 4
DP  - 2012
TI  - Excitability of intracortical inhibitory and facilitatory circuits during 
      ischemic nerve block.
PG  - 345-54
LID - 10.3233/RNN-2012-110198 [doi]
AB  - PURPOSE: The primary motor cortex is capable of rapid, reversible plastic changes 
      and longer-term, more permanent reorganization. Ischemic nerve block (INB) is a 
      model of deafferentation-induced short-term plasticity. We used transcranial 
      magnetic stimulation to examine whether changes in the excitability of short- 
      and/or long-interval intracortical inhibitory (SICI, LICI) or short-interval 
      intracortical facilitatory (SICF) circuits underlie the corticospinal 
      excitability increases observed during INB. METHODS: SICI and LICI recruitment 
      curves, obtained by varying conditioning stimulus intensity, and SICF were 
      measured at multiple inter-stimulus intervals (ISIs). RESULTS: Forearm flexor MEP 
      amplitude increased during INB at the wrist; this was not accompanied by changes 
      in SICI at ISIs of 1 or 2 ms, in SICF at ISIs of 1.2, 2.7, or 4.4 ms, or in LICI 
      at an ISI of 80 ms, but was accompanied by an increase in LICI at an ISI of 150 
      ms. CONCLUSIONS: The results suggest that (1) the increased excitability of 
      forearm flexors is not due to reduced SICI or LICI or increased SICF, and (2) 
      LICI measured at ISIs of 80 and 150 ms are distinct processes. We discuss the 
      importance of identifying distinct processes of LICI and speculate regarding 
      other mechanisms that could potentially underlie INB-induced plasticity.
FAU - Vallence, Ann-Maree
AU  - Vallence AM
AD  - School of Psychology, The University of Western Australia, WA, Australia. 
      annmaree.vallence@gmail.com
FAU - Reilly, Karen
AU  - Reilly K
FAU - Hammond, Geoff
AU  - Hammond G
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - Netherlands
TA  - Restor Neurol Neurosci
JT  - Restorative neurology and neuroscience
JID - 9005499
SB  - IM
MH  - Adult
MH  - Brain Ischemia/*physiopathology
MH  - Evoked Potentials, Motor/*physiology
MH  - Female
MH  - Humans
MH  - Male
MH  - Nerve Block/*adverse effects
MH  - Neural Inhibition/*physiology
MH  - Reaction Time
MH  - Transcranial Magnetic Stimulation
MH  - Young Adult
EDAT- 2012/05/19 06:00
MHDA- 2012/12/10 06:00
CRDT- 2012/05/19 06:00
PHST- 2012/05/19 06:00 [entrez]
PHST- 2012/05/19 06:00 [pubmed]
PHST- 2012/12/10 06:00 [medline]
AID - 8G013XL48705P486 [pii]
AID - 10.3233/RNN-2012-110198 [doi]
PST - ppublish
SO  - Restor Neurol Neurosci. 2012;30(4):345-54. doi: 10.3233/RNN-2012-110198.