What Do TMS-Evoked Motor Potentials Tell Us About Motor Learning?

  • Richard G. CarsonEmail author
  • Kathy L. Ruddy
  • Emmet McNickle
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 957)


Thirty years ago, the first magnetic device capable of stimulating the human brain without discomfort through the intact skull was unveiled in Sheffield, England (Barker et al. in Lancet 1:1106–1107, 1985). Since that time, transcranial magnetic stimulation (TMS) has become the tool of choice for many scientists investigating human motor control and learning. In light of the fact that there are limits to the information that can be provided by any experimental technique, we first make the case that the necessarily restricted explanatory scope of the TMS technique—and the motor-evoked potentials to which it gives rise, is not yet reflected adequately in the research literature. We also argue that this inattention, coupled with the pervasive adoption of TMS as an investigative tool, may be restricting the elaboration of knowledge concerning the neural processes that mediate human motor learning. In order to make these points, we use as an exemplar the study of cross-education—the interlimb transfer of functional capacity.


Transcranial Magnetic stimulation Interlimb transfer Functional capacity Cross-education Motor-evoked potentials MEP amplitude Corticospinal Primary motor cortex 


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Copyright information

© Springer International Publishing AG 2016

Authors and Affiliations

  • Richard G. Carson
    • 1
    • 2
    Email author
  • Kathy L. Ruddy
    • 3
  • Emmet McNickle
    • 1
  1. 1.Trinity College Institute of Neuroscience and School of PsychologyTrinity College DublinDublin 2Ireland
  2. 2.School of PsychologyQueen’s University BelfastNorthern IrelandUK
  3. 3.Neural Control of Movement LabETHZurichSwitzerland

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