PMID- 25103026
OWN - NLM
STAT- MEDLINE
DCOM- 20150615
LR  - 20181202
IS  - 1876-4754 (Electronic)
IS  - 1876-4754 (Linking)
VI  - 7
IP  - 5
DP  - 2014 Sep-Oct
TI  - Interaction between different interneuron networks involved in human associative 
      plasticity.
PG  - 658-64
LID - S1935-861X(14)00180-6 [pii]
LID - 10.1016/j.brs.2014.05.010 [doi]
AB  - BACKGROUND: Paired associative stimulation (PAS) is a widely used method to study 
      spike timing dependent plasticity in motor cortex. Repeated pairing of an 
      electrical stimulus to the median nerve with transcranial magnetic stimulation 
      (TMS) over the contralateral motor cortex at interstimulus intervals (ISIs) of 
      21.5-25 ms leads to a long term potentiation (LTP)-like synaptic plasticity in 
      the corticospinal system. Previously we found that concurrent transcranial direct 
      current stimulation (TDCS) over cerebellum blocked the effect of PAS25 but not 
      PAS21.5, implying that two separate mechanisms were involved. OBJECTIVE: We 
      hypothesized that if PAS21.5 and PAS25 increased corticospinal excitability by 
      two entirely separate mechanisms then their effects might summate if we 
      intermixed them in the same session. METHODS: Twenty-four healthy volunteers were 
      studied. Eight subjects were selected who showed the expected facilitation after 
      both standard PAS21.5 and PAS25 with 180 pairs. They participated to two sessions 
      in which PAS consisted of 360 electrical stimuli of the right median nerve paired 
      with a single TMS over the hotspot of right APB at randomly delivered ISIs of 
      25 ms and of 21.5 ms (180 pairs for each ISI) (PASvar360p). Either sham or anodal 
      TDCS (2 mA, 30 min) was applied to the cerebellum simultaneously with PASvar360p. 
      Subsequently, we applied a protocol with 90 pairs for each ISI (PASvar180p). We 
      measured motor evoked potentials (MEPs) before and after each intervention. 
      RESULTS: Although PAS21.5 and PAS25 each produce corticospinal facilitation when 
      applied alone, the after-effects disappeared if we randomly intermixed PAS21.5 
      and PAS25 using either 180 pairs (PASvar360p) or 90 pairs (PASvar180p) for each 
      ISI. Facilitation is restored if anodal but not sham TDCS is applied concurrently 
      over the cerebellum to block the effect of PAS25. CONCLUSIONS: PAS21.5 and PAS25 
      not only engage two separate mechanisms but also they are mutually inhibitory.
CI  - Copyright (c) 2014 Elsevier Inc. All rights reserved.
FAU - Strigaro, Gionata
AU  - Strigaro G
AD  - Sobell Department of Motor Neuroscience and Movement Disorders, University 
      College London Institute of Neurology, London, United Kingdom; Department of 
      Translational Medicine, Section of Neurology, University of Piemonte Orientale 
      ''A. Avogadro'', Novara, Italy.
FAU - Hamada, Masashi
AU  - Hamada M
AD  - Sobell Department of Motor Neuroscience and Movement Disorders, University 
      College London Institute of Neurology, London, United Kingdom; Department of 
      Neurology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan. 
      Electronic address: mhamada-tky@umin.net.
FAU - Murase, Nagako
AU  - Murase N
AD  - Sobell Department of Motor Neuroscience and Movement Disorders, University 
      College London Institute of Neurology, London, United Kingdom; Department of 
      Neurology, National Hospital Organization Kyoto Medical Center, Kyoto, Japan.
FAU - Cantello, Roberto
AU  - Cantello R
AD  - Department of Translational Medicine, Section of Neurology, University of 
      Piemonte Orientale ''A. Avogadro'', Novara, Italy.
FAU - Rothwell, John C
AU  - Rothwell JC
AD  - Sobell Department of Motor Neuroscience and Movement Disorders, University 
      College London Institute of Neurology, London, United Kingdom.
LA  - eng
PT  - Journal Article
PT  - Randomized Controlled Trial
PT  - Research Support, Non-U.S. Gov't
DEP - 20140608
PL  - United States
TA  - Brain Stimul
JT  - Brain stimulation
JID - 101465726
SB  - IM
MH  - Adolescent
MH  - Adult
MH  - Electric Stimulation/methods
MH  - Evoked Potentials, Motor/*physiology
MH  - Female
MH  - Humans
MH  - Interneurons/*physiology
MH  - Long-Term Potentiation/physiology
MH  - Male
MH  - Median Nerve/physiology
MH  - Middle Aged
MH  - Motor Cortex/*physiology
MH  - Nerve Net/*physiology
MH  - Neuronal Plasticity/*physiology
MH  - Transcranial Magnetic Stimulation/*methods
MH  - Young Adult
OTO - NOTNLM
OT  - Associative plasticity
OT  - Heterosynaptic interaction
OT  - Transcranial magnetic stimulation
EDAT- 2014/08/12 06:00
MHDA- 2015/06/16 06:00
CRDT- 2014/08/09 06:00
PHST- 2014/01/12 00:00 [received]
PHST- 2014/05/31 00:00 [revised]
PHST- 2014/05/31 00:00 [accepted]
PHST- 2014/08/09 06:00 [entrez]
PHST- 2014/08/12 06:00 [pubmed]
PHST- 2015/06/16 06:00 [medline]
AID - S1935-861X(14)00180-6 [pii]
AID - 10.1016/j.brs.2014.05.010 [doi]
PST - ppublish
SO  - Brain Stimul. 2014 Sep-Oct;7(5):658-64. doi: 10.1016/j.brs.2014.05.010. Epub 2014 
      Jun 8.