PMID- 12068053
OWN - NLM
STAT- MEDLINE
DCOM- 20030110
LR  - 20190513
IS  - 0022-3751 (Print)
IS  - 1469-7793 (Electronic)
IS  - 0022-3751 (Linking)
VI  - 541
IP  - Pt 3
DP  - 2002 Jun 15
TI  - Interaction of transcranial magnetic stimulation and electrical transmastoid 
      stimulation in human subjects.
PG  - 949-58
AB  - Transcranial magnetic stimulation activates corticospinal neurones directly and 
      transsynaptically and hence, activates motoneurones and results in a response in 
      the muscle. Transmastoid stimulation results in a similar muscle response through 
      activation of axons in the spinal cord. This study was designed to determine 
      whether the two stimuli activate the same descending axons. Responses to 
      transcranial magnetic stimuli paired with electrical transmastoid stimuli were 
      examined in biceps brachii in human subjects. Twelve interstimulus intervals 
      (ISIs) from -6 ms (magnet before transmastoid) to 5 ms were investigated. When 
      responses to the individual stimuli were set at 10-15 % of the maximal M-wave, 
      responses to the paired stimuli were larger than expected at ISIs of -6 and -5 ms 
      but were reduced in size at ISIs of -2 to 1 ms and at 3 to 5 ms. With individual 
      responses of 3-5 % of maximal M-wave, facilitation still occurred at ISIs of -6 
      and -5 ms and depression of the paired response at ISIs of 0, 1, 4 and 5 ms. The 
      interaction of the response to transmastoid stimulation with the multiple 
      descending volleys elicited by magnetic stimulation of the cortex is complex. 
      However, depression of the response to the paired stimuli at short ISIs is 
      consistent with an occlusive interaction in which an antidromic volley evoked by 
      the transmastoid stimulus collides with and annihilates descending action 
      potentials evoked by the transcranial magnetic stimulus. Thus, it is consistent 
      with the two stimuli activating some of the same corticospinal axons.
FAU - Taylor, Janet L
AU  - Taylor JL
AD  - Prince of Wales Medical Research Institute, Barker Street, Randwick, NSW 2031, 
      Australia. jl.taylor@unsw.edu.au
FAU - Petersen, N T
AU  - Petersen NT
FAU - Butler, Jane E
AU  - Butler JE
FAU - Gandevia, S C
AU  - Gandevia SC
LA  - eng
PT  - Clinical Trial
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  - Axons/physiology
MH  - Brain/*physiology
MH  - Cerebral Cortex/physiology
MH  - Electric Stimulation
MH  - *Electromagnetic Fields
MH  - Humans
MH  - Middle Aged
MH  - Muscle, Skeletal/innervation/*physiology
MH  - Time Factors
PMC - PMC2290352
EDAT- 2002/06/18 10:00
MHDA- 2003/01/11 04:00
PMCR- 2003/06/15
CRDT- 2002/06/18 10:00
PHST- 2002/06/18 10:00 [pubmed]
PHST- 2003/01/11 04:00 [medline]
PHST- 2002/06/18 10:00 [entrez]
PHST- 2003/06/15 00:00 [pmc-release]
AID - PHY_16782 [pii]
AID - 10.1113/jphysiol.2002.016782 [doi]
PST - ppublish
SO  - J Physiol. 2002 Jun 15;541(Pt 3):949-58. doi: 10.1113/jphysiol.2002.016782.