PMID- 25561164
OWN - NLM
STAT- MEDLINE
DCOM- 20151214
LR  - 20150919
IS  - 1872-8952 (Electronic)
IS  - 1388-2457 (Linking)
VI  - 126
IP  - 10
DP  - 2015 Oct
TI  - Interhemispheric inhibition of corticospinal projections to forearm muscles.
PG  - 1934-40
LID - S1388-2457(14)00850-5 [pii]
LID - 10.1016/j.clinph.2014.12.006 [doi]
AB  - OBJECTIVE: Interhemispheric inhibition (IHI) is typically examined via responses 
      elicited in intrinsic hand muscles. As the cortical representations of proximal 
      and distal muscles in the upper limb are distinguished in terms of their 
      inter-hemispheric projections, we sought to determine whether the IHI parameters 
      established for the hand apply more generally. METHODS: We investigated IHI at 5 
      different conditioning stimulus (CS) intensities and a range of short-latency 
      inter-stimulus intervals (ISIs) in healthy participants. Conditioning and test 
      stimuli were delivered over the M1 representation of the right and left flexor 
      carpi radialis respectively. RESULTS: IHI increased as a function of CS 
      intensity, and was present for ISIs between 7 and 15ms. Inhibition was most 
      pronounced for the 10ms ISI at all CS intensities. CONCLUSIONS: The range of 
      parameters for which IHI is elicited in projections to the forearm is similar to 
      that reported for the hand. The specific utility lies in delineation of stimulus 
      parameters that permit both potentiation and attenuation of IHI to be assessed. 
      SIGNIFICANCE: In light of evidence that there is a greater density of callosal 
      projections between cortical areas that represent proximal muscles than between 
      those corresponding to distal limb muscles, and in view of the assumption that 
      variations in functional connectivity to which such differences give rise may 
      have important implications for motor behavior, it is critical to determine 
      whether processes mediating the expression of IHI depend on the effector that is 
      studied. This issue is of further broad significance given the practical utility 
      of movements generated by muscles proximal to the wrist in the context of upper 
      limb rehabilitation.
CI  - Copyright (c) 2014 International Federation of Clinical Neurophysiology. Published 
      by Elsevier Ireland Ltd. All rights reserved.
FAU - Ibey, R J
AU  - Ibey RJ
AD  - Department of Kinesiology, University of Waterloo, Waterloo, Canada.
FAU - Bolton, D A E
AU  - Bolton DA
AD  - School of Psychology, Queen's University Belfast, Northern Ireland, UK. 
      Electronic address: d.bolton@qub.ac.uk.
FAU - Buick, A R
AU  - Buick AR
AD  - School of Psychology, Queen's University Belfast, Northern Ireland, UK.
FAU - Staines, W R
AU  - Staines WR
AD  - Department of Kinesiology, University of Waterloo, Waterloo, Canada.
FAU - Carson, R G
AU  - Carson RG
AD  - School of Psychology, Queen's University Belfast, Northern Ireland, UK; Trinity 
      College Institute of Neuroscience and School of Psychology, Trinity College 
      Dublin, Ireland.
LA  - eng
GR  - BB/I008101/1/Biotechnology and Biological Sciences Research Council/United 
      Kingdom
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20141215
PL  - Netherlands
TA  - Clin Neurophysiol
JT  - Clinical neurophysiology : official journal of the International Federation of 
      Clinical Neurophysiology
JID - 100883319
SB  - IM
MH  - Adult
MH  - Electromyography/methods
MH  - Evoked Potentials, Motor/physiology
MH  - Female
MH  - Forearm/innervation/*physiology
MH  - Humans
MH  - Motor Cortex/*physiology
MH  - Neural Inhibition/*physiology
MH  - Pyramidal Tracts/*physiology
MH  - Transcranial Magnetic Stimulation/*methods
MH  - Young Adult
OTO - NOTNLM
OT  - Electromyography
OT  - Interhemispheric inhibition
OT  - Proximal muscles
OT  - Transcranial magnetic stimulation
OT  - Upper limb
EDAT- 2015/01/07 06:00
MHDA- 2015/12/15 06:00
CRDT- 2015/01/07 06:00
PHST- 2014/08/08 00:00 [received]
PHST- 2014/11/26 00:00 [revised]
PHST- 2014/12/06 00:00 [accepted]
PHST- 2015/01/07 06:00 [entrez]
PHST- 2015/01/07 06:00 [pubmed]
PHST- 2015/12/15 06:00 [medline]
AID - S1388-2457(14)00850-5 [pii]
AID - 10.1016/j.clinph.2014.12.006 [doi]
PST - ppublish
SO  - Clin Neurophysiol. 2015 Oct;126(10):1934-40. doi: 10.1016/j.clinph.2014.12.006. 
      Epub 2014 Dec 15.