Effect of pain and pain expectation on primary motor cortex excitability

Clin Neurophysiol. 2011 Nov;122(11):2318-23. doi: 10.1016/j.clinph.2011.03.026. Epub 2011 May 20.


Objective: The study aimed to test whether pain and pain expectation affect corticospinal excitability.

Methods: Transcranial magnetic stimulation was used to measure corticospinal excitability among 15 subjects in five experimental conditions in which thermic stimulations were applied to the hand: (1) neutral stimulus; (2) actual heat; (3) actual pain; (4) expected heat; and (5) expected pain. Motor-evoked potentials were recorded in two intrinsic hand muscles.

Results: A significant difference was found between experimental conditions for both muscles (p<0.005). Contrast analysis showed that actual pain led to a significant corticospinal inhibition compared with both neutral and actual heat conditions, whereas no effect was observed during pain expectation.

Conclusions: Our results suggest that acute pain (low-to-moderate intensity (∼3/10)) does elicit motor inhibition but that its expectation does not.

Significance: The fact that low and short-lasting pain can induce motor inhibition suggests that even moderate pain might interfere with optimal motor function in patients with both pain and motor deficits.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Anticipation, Psychological / physiology*
  • Evoked Potentials, Motor / physiology*
  • Female
  • Hot Temperature / adverse effects
  • Humans
  • Male
  • Motor Cortex / physiology*
  • Neural Conduction / physiology
  • Neural Inhibition / physiology
  • Pain / physiopathology*
  • Pain / psychology
  • Pain Measurement / methods
  • Pain Threshold / physiology*
  • Pyramidal Tracts / physiology*
  • Transcranial Magnetic Stimulation / methods
  • Young Adult