PMID- 19679111
OWN - NLM
STAT- MEDLINE
DCOM- 20091229
LR  - 20090928
IS  - 1872-6240 (Electronic)
IS  - 0006-8993 (Linking)
VI  - 1296
DP  - 2009 Nov 3
TI  - Forty-hertz triple-pulse stimulation induces motor cortical facilitation in 
      humans.
PG  - 15-23
LID - 10.1016/j.brainres.2009.08.008 [doi]
AB  - A single pulse of transcranial magnetic stimulation (TMS) can reset the 15- to 
      30-Hz beta-band oscillations in the motor cortex. These oscillations are known to 
      influence the amplitude of corticospinal activity evoked by TMS. To garner 
      further evidence for this resetting, we tested how electromyographic responses to 
      motor cortex TMS were modulated by a preceding series of TMS pulses. We used a 
      triad of conditioning TMS pulses at various interstimulus intervals (ISIs) in an 
      attempt to drive cortical activity at the corresponding frequency. We then 
      analyzed how the amplitude of motor-evoked potentials (MEPs) to a test pulse 
      varied at different intervals after the conditioning triad. When conditioning 
      pulses were given at an ISI of 25 ms, responses to the fourth (test) pulse were 
      facilitated 25 ms later. Neither a single conditioning pulse nor triad of 
      conditioning pulses separated by other ISIs enhanced responses to the test pulse 
      at the expected timings. Triads of pulses at an ISI of 25 ms did not enhance 
      subsequent MEPs to brainstem stimulation. Based on the intensity of the 
      conditioning stimuli necessary to produce this effect and on the effective 
      interval, we conclude that the facilitation at 25 ms differs from intracortical 
      facilitation at 7-10 ms seen in the paired-pulse experiment originally reported 
      by Kujirai et al. These results suggest that a triad of TMS pulses can enhance an 
      intrinsic oscillatory rhythm of the motor cortex (40 Hz) and facilitate cortical 
      activity at an ISI corresponding to the frequency of that rhythm.
FAU - Hanajima, Ritsuko
AU  - Hanajima R
AD  - Department of Neurology, Division of Neuroscience, Graduate School of Medicine, 
      University of Tokyo, Tokyo, Japan. hanajima-tky@umin.ac.jp
FAU - Terao, Yasuo
AU  - Terao Y
FAU - Hamada, Masashi
AU  - Hamada M
FAU - Okabe, Shingo
AU  - Okabe S
FAU - Nakatani-Enomoto, Setsu
AU  - Nakatani-Enomoto S
FAU - Furubayashi, Toshiaki
AU  - Furubayashi T
FAU - Yugeta, Akihiro
AU  - Yugeta A
FAU - Inomata-Terada, Satomi
AU  - Inomata-Terada S
FAU - Ugawa, Yoshikazu
AU  - Ugawa Y
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20090811
PL  - Netherlands
TA  - Brain Res
JT  - Brain research
JID - 0045503
SB  - IM
MH  - Adult
MH  - Analysis of Variance
MH  - Brain Stem/physiology
MH  - Electromyography
MH  - Evoked Potentials, Motor
MH  - Female
MH  - Humans
MH  - Male
MH  - Middle Aged
MH  - Motor Cortex/*physiology
MH  - Time Factors
MH  - Transcranial Magnetic Stimulation/*methods
EDAT- 2009/08/15 09:00
MHDA- 2009/12/30 06:00
CRDT- 2009/08/15 09:00
PHST- 2009/04/06 00:00 [received]
PHST- 2009/07/08 00:00 [revised]
PHST- 2009/08/04 00:00 [accepted]
PHST- 2009/08/15 09:00 [entrez]
PHST- 2009/08/15 09:00 [pubmed]
PHST- 2009/12/30 06:00 [medline]
AID - S0006-8993(09)01634-5 [pii]
AID - 10.1016/j.brainres.2009.08.008 [doi]
PST - ppublish
SO  - Brain Res. 2009 Nov 3;1296:15-23. doi: 10.1016/j.brainres.2009.08.008. Epub 2009 
      Aug 11.