Experimental Brain Research

, Volume 196, Issue 4, pp 529–535

Influence of touching an object on corticospinal excitability during motor imagery

  • Nobuaki Mizuguchi
  • Masanori Sakamoto
  • Tetsuro Muraoka
  • Kazuyuki Kanosue
Research Article

DOI: 10.1007/s00221-009-1875-5

Cite this article as:
Mizuguchi, N., Sakamoto, M., Muraoka, T. et al. Exp Brain Res (2009) 196: 529. doi:10.1007/s00221-009-1875-5
  • 183 Downloads

Abstract

We investigated whether corticospinal excitability during the imagery of an action involving an external object was influenced by actually touching the object. Corticospinal excitability was assessed by monitoring motor evoked potentials (MEPs) in the first dorsal interosseous muscle following transcranial magnetic stimulation over the motor cortex during imagery of squeezing a ball—with or without passively holding the ball. The MEPs amplitude during imagery when the ball was held was larger than that when the ball was not held. The MEPs amplitude was not modulated just by holding the ball. In the same experimental condition, the somatosensory evoked potentials (SEPs) in response to the stimulation of median nerve were not modulated by motor imagery or by holding the ball. These results suggest that the corticospinal excitability during imagery of squeezing a ball is enhanced with the real touch of the ball, and the enhancement would be caused by some changes along the corticospinal pathway itself and not by the change in responsiveness along the afferent pathway to the primary somatosensory cortex.

Keywords

Motor imageryTranscranial magnetic stimulation (TMS)Motor evoked potentials (MEPs)Somatosensory evoked potentials (SEPs)

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Nobuaki Mizuguchi
    • 1
  • Masanori Sakamoto
    • 2
  • Tetsuro Muraoka
    • 3
  • Kazuyuki Kanosue
    • 2
    • 3
  1. 1.Graduate School of Sport SciencesWaseda UniversityTokorozawaJapan
  2. 2.Faculty of Sport SciencesWaseda UniversityTokorozawaJapan
  3. 3.Consolidated Research Institute for Advanced Science and Medical CareWaseda UniversityTokorozawaJapan