PMID- 12804678
OWN - NLM
STAT- MEDLINE
DCOM- 20030801
LR  - 20190922
IS  - 1388-2457 (Print)
IS  - 1388-2457 (Linking)
VI  - 114
IP  - 6
DP  - 2003 Jun
TI  - Effects of transcranial magnetic stimulation on the H reflex and F wave in the 
      hand muscles.
PG  - 1096-101
AB  - OBJECTIVE: In 14 healthy subjects, we studied the effects of transcranial 
      magnetic stimulation (TMS) on the excitability of spinal motoneurons in the 
      abductor pollicis brevis muscle (ABP), by testing the F wave and H reflex. 
      METHODS: TMS pulses were delivered with the subjects at rest and at various motor 
      threshold (Mth) intensities. Electrical stimuli were delivered to the median 
      nerve at the wrist at two different intensities. High-intensity pulse was used to 
      evoke an F wave and low-intensity paired pulse to evoke an H reflex in the ABP 
      muscle. The effects of TMS were studied using a conditioning-test paradigm. The 
      tests F wave and H reflex were conditioned by TMS (120% Mth) at various 
      interstimulus intervals (ISIs) (30-100ms) and intensities (90-200% Mth). RESULTS: 
      At 30ms but not at ISIs from 40 to 100ms, conditioning TMS (120% Mth) 
      significantly increased the F-wave area. At the 30ms ISI, conditioning TMS at 
      120% Mth intensity significantly increased the F-wave area whereas higher 
      intensities (140-180% Mth) did not. At 200% Mth intensity, the F-wave area 
      decreased significantly. At 30 and 40ms ISIs, conditioning TMS at 120% Mth 
      significantly reduced the H-reflex area. At 50-100ms ISIs, the H-reflex area 
      almost matched the control value. At the 30ms ISI, conditioning TMS at >or=100% 
      Mth intensity significantly decreased the H-reflex area. CONCLUSIONS: In 
      conclusion, our findings suggest that the distinct changes in the TMS-conditioned 
      F wave and H reflex reflect changing excitability in the motoneuronal populations 
      activated by the cortical input.
FAU - Inghilleri, M
AU  - Inghilleri M
AD  - Dipartimento Scienze Neurologiche, Universita di Roma La Sapienza, Viale 
      Universita, 30, 00185, Rome, Italy. maurizio.inghilleri@uniforma1.it
FAU - Lorenzano, C
AU  - Lorenzano C
FAU - Conte, A
AU  - Conte A
FAU - Frasca, V
AU  - Frasca V
FAU - Manfredi, M
AU  - Manfredi M
FAU - Berardelli, A
AU  - Berardelli A
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PL  - Netherlands
TA  - Clin Neurophysiol
JT  - Clinical neurophysiology : official journal of the International Federation of 
      Clinical Neurophysiology
JID - 100883319
SB  - IM
MH  - Adult
MH  - Electric Stimulation/*methods
MH  - Electromyography/methods
MH  - Evoked Potentials, Motor
MH  - Female
MH  - H-Reflex/*physiology
MH  - Hand/*physiology
MH  - Humans
MH  - Male
MH  - Median Nerve/physiology
MH  - Middle Aged
MH  - Motor Cortex/physiology
MH  - Muscle, Skeletal/*physiology
MH  - Neural Conduction
MH  - Time Factors
MH  - *Transcranial Magnetic Stimulation
EDAT- 2003/06/14 05:00
MHDA- 2003/08/02 05:00
CRDT- 2003/06/14 05:00
PHST- 2003/06/14 05:00 [pubmed]
PHST- 2003/08/02 05:00 [medline]
PHST- 2003/06/14 05:00 [entrez]
AID - S1388245703000567 [pii]
AID - 10.1016/s1388-2457(03)00056-7 [doi]
PST - ppublish
SO  - Clin Neurophysiol. 2003 Jun;114(6):1096-101. doi: 10.1016/s1388-2457(03)00056-7.