PMID- 19683960
OWN - NLM
STAT- MEDLINE
DCOM- 20090923
LR  - 20211028
IS  - 1872-8952 (Electronic)
IS  - 1388-2457 (Linking)
VI  - 120
IP  - 9
DP  - 2009 Sep
TI  - Inhibitory and facilitatory connectivity from ventral premotor to primary motor 
      cortex in healthy humans at rest--a bifocal TMS study.
PG  - 1724-31
LID - 10.1016/j.clinph.2009.07.035 [doi]
AB  - OBJECTIVE: In macaques, intracortical electrical stimulation of ventral premotor 
      cortex (PMv) can modulate ipsilateral primary motor cortex (M1) excitability at 
      short interstimulus intervals (ISIs). METHODS: Adopting the same 
      conditioning-test approach, we used bifocal transcranial magnetic stimulation 
      (TMS) to examine intrahemispheric connectivity between left PMv and M1 in humans. 
      A conditioning stimulus (CS) was applied to PMv at intensities of 80% and 90% of 
      active motor threshold (AMT) and 90% and 110% of resting motor threshold (RMT). A 
      supra-threshold test stimulus (TS) was given 2, 4, 6, 8 and 10 ms after the CS 
      and the amplitude of the motor evoked potential (MEP) was measured to probe 
      corticospinal excitability. RESULTS: The CS facilitated corticospinal 
      excitability in ipsilateral M1 when PMv was stimulated with 80% AMT 4 or 6 ms 
      before the TS. At the same ISIs, the CS suppressed corticospinal excitability 
      when the stimulus intensity was increased to 90% RMT. Conditioning effects were 
      site-specific because conditioning the dorsal premotor cortex (PMd) at three 
      different sites produced different effects. Using neuronavigated TMS the PMv site 
      where applied CS produced changes in ipsilateral M1 excitability was located at 
      the border between ventral Brodmann area (BA) 6 and BA 44, the human homologue of 
      monkey's PMv (area F5). CONCLUSION: We infer that the corticospinal motor output 
      from M1 to contralateral hand muscles can be facilitated or inhibited by a CS 
      over ipsilateral PMv. SIGNIFICANCE: The fact that conditioning effects following 
      PMd stimulation differ from those after PMv stimulation supports the concept that 
      inputs from premotor cortices to M1 are functionally segregated.
FAU - Baumer, T
AU  - Baumer T
AD  - Department of Neurology, University Medical Center Hamburg Eppendorf, Hamburg, 
      Germany. baeumer@uke.uni-hamburg.de
FAU - Schippling, S
AU  - Schippling S
FAU - Kroeger, J
AU  - Kroeger J
FAU - Zittel, S
AU  - Zittel S
FAU - Koch, G
AU  - Koch G
FAU - Thomalla, G
AU  - Thomalla G
FAU - Rothwell, J C
AU  - Rothwell JC
FAU - Siebner, H R
AU  - Siebner HR
FAU - Orth, M
AU  - Orth M
FAU - Munchau, A
AU  - Munchau A
LA  - eng
GR  - G0500258/MRC_/Medical Research Council/United Kingdom
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20090815
PL  - Netherlands
TA  - Clin Neurophysiol
JT  - Clinical neurophysiology : official journal of the International Federation of 
      Clinical Neurophysiology
JID - 100883319
SB  - IM
MH  - Adult
MH  - Data Interpretation, Statistical
MH  - Electromyography
MH  - Evoked Potentials, Motor/physiology
MH  - Female
MH  - Functional Laterality/physiology
MH  - Humans
MH  - Male
MH  - Motor Cortex/*physiology
MH  - Neural Pathways/*physiology
MH  - Prefrontal Cortex/physiology
MH  - Rest/physiology
MH  - *Transcranial Magnetic Stimulation
MH  - Young Adult
EDAT- 2009/08/18 09:00
MHDA- 2009/09/24 06:00
CRDT- 2009/08/18 09:00
PHST- 2008/07/11 00:00 [received]
PHST- 2009/07/09 00:00 [revised]
PHST- 2009/07/14 00:00 [accepted]
PHST- 2009/08/18 09:00 [entrez]
PHST- 2009/08/18 09:00 [pubmed]
PHST- 2009/09/24 06:00 [medline]
AID - S1388-2457(09)00459-3 [pii]
AID - 10.1016/j.clinph.2009.07.035 [doi]
PST - ppublish
SO  - Clin Neurophysiol. 2009 Sep;120(9):1724-31. doi: 10.1016/j.clinph.2009.07.035. 
      Epub 2009 Aug 15.