A comparison of two methods in acquiring stimulus-response curves with transcranial magnetic stimulation

Brain Stimul. 2013 May;6(3):306-9. doi: 10.1016/j.brs.2012.05.010. Epub 2012 Jun 15.


Background: The stimulus-response (S-R) curve is a well accepted constituent in transcranial magnetic stimulation (TMS) studies. However, it has been suggested that parameters of the S-R curve differ when stimuli are provided in a "ramped" (measured steps from low to high intensity), or "random" fashion.

Hypothesis: We hypothesized that there would be no difference in the parameters of the S-R curve between either methodologies.

Methods: Using a randomised cross-over design, 10 healthy participants (29.6 ± 6.4 yrs, 3 f) completed "ramped" or "random" curves in biceps brachii (BB) and first dorsal interosseous (FDI) muscles of both limbs. Curves were compared using mixed-factor ANOVA and correlated between limbs and methodologies.

Results: No differences (P > 0.05) and high correlations (range 0.71-0.97; P < 0.001) were observed in BB and FDI data between curves.

Conclusions: This study demonstrated that either methodology provides similar parameters of the S-R curve in healthy participants.

Publication types

  • Comparative Study
  • Pragmatic Clinical Trial

MeSH terms

  • Adult
  • Cross-Sectional Studies
  • Electromyography
  • Evoked Potentials, Motor / physiology*
  • Female
  • Functional Laterality / physiology
  • Hand / innervation
  • Humans
  • Male
  • Motor Cortex / physiology*
  • Muscle, Skeletal / physiology*
  • Transcranial Magnetic Stimulation*