PMID- 8558482
OWN - NLM
STAT- MEDLINE
DCOM- 19960227
LR  - 20190512
IS  - 0022-3751 (Print)
IS  - 1469-7793 (Electronic)
IS  - 0022-3751 (Linking)
VI  - 487 ( Pt 2)
IP  - Pt 2
DP  - 1995 Sep 1
TI  - The effect of voluntary contraction on cortico-cortical inhibition in human motor 
      cortex.
PG  - 541-8
AB  - 1. It has been previously shown that in a relaxed target muscle, at short 
      interstimulus intervals (ISIs) (up to 6 ms) a conditioning subthreshold 
      transcranial magnetic stimulus can cause suppression of the EMG response evoked 
      by a magnetic test stimulus. At longer ISIs (7-15 ms) facilitation of the test 
      response is seen. This type of inhibition has been termed ipsilateral 
      cortico-cortical inhibition. 2. The effect of a minimal tonic contraction on 
      ipsilateral cortico-cortical inhibition has been investigated in the first dorsal 
      interrosseous (FDI). 3. At short ISIs there was significantly less inhibition of 
      the test response during the maintenance of minimal voluntary tonic contraction 
      of the target muscle (FDI). 4. At longer ISIs (7-15 ms) there was significantly 
      less facilitation of the test response during a tonic contraction than during 
      relaxation. 5. Minimal activation of an ipsilateral proximal muscle (biceps) had 
      no significant effect on the degree of inhibition seen in the relaxed target 
      muscle (FDI). 6. We suggest that voluntary drive reduces the excitability of 
      inhibitory circuits in cortical areas that project to the active muscle.
FAU - Ridding, M C
AU  - Ridding MC
AD  - MRC Human Movement and Balance Unit, Institute of Neurology, London, UK.
FAU - Taylor, J L
AU  - Taylor JL
FAU - Rothwell, J C
AU  - Rothwell JC
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - J Physiol
JT  - The Journal of physiology
JID - 0266262
SB  - IM
MH  - Adult
MH  - Electromyography
MH  - Female
MH  - Humans
MH  - Male
MH  - Middle Aged
MH  - Motor Cortex/*physiology
MH  - Muscle Contraction/*physiology
MH  - Muscle, Skeletal/innervation/*physiology
PMC - PMC1156591
EDAT- 1995/09/01 00:00
MHDA- 1995/09/01 00:01
PMCR- 1995/09/01
CRDT- 1995/09/01 00:00
PHST- 1995/09/01 00:00 [pubmed]
PHST- 1995/09/01 00:01 [medline]
PHST- 1995/09/01 00:00 [entrez]
PHST- 1995/09/01 00:00 [pmc-release]
AID - 10.1113/jphysiol.1995.sp020898 [doi]
PST - ppublish
SO  - J Physiol. 1995 Sep 1;487 ( Pt 2)(Pt 2):541-8. doi: 
      10.1113/jphysiol.1995.sp020898.