Subthreshold 5-Hz repetitive transcranial magnetic stimulation of the human primary motor cortex reduces intracortical paired-pulse inhibition

Neurosci Lett. 2000 Dec 15;296(1):21-4. doi: 10.1016/s0304-3940(00)01616-5.


Paired-pulse transcranial magnetic stimulation (TMS) at short interstimulus intervals was employed to investigate short-term effects of 5-Hz repetitive TMS (rTMS) over the primary motor hand area (M1(HAND)) on intracortical excitability. In ten healthy individuals, 1250 pulses of 5-Hz rTMS were applied at 90% of motor resting threshold over the left M1(HAND). Ten minutes after 5-Hz rTMS, paired-pulse inhibition was significantly reduced, whereas paired-pulse facilitation was not modified. Sham-rTMS had no lasting effect on intracortical excitability. These findings suggest that subthreshold 5-Hz rTMS causes a short-term modulation of the excitability of intracortical circuitry in the stimulated M1(HAND). The lasting effect of subthreshold 5-Hz rTMS on intracortical inhibition provides a useful probe for studying short-term plasticity of the human M1(HAND).

MeSH terms

  • Adult
  • Cerebral Cortex / physiology*
  • Electromagnetic Phenomena*
  • Electromyography
  • Female
  • Functional Laterality
  • Hand / innervation
  • Humans
  • Male
  • Motor Cortex / physiology*
  • Muscle, Skeletal / innervation*
  • Time Factors