The aim of the current study was to clarify how corticospinal excitability (CSE) is modulated during the observation of the action of walking, combined with motor imagery (MI). We examined the difference in phase modulation of CSE with and without MI during the observation of the action of walking. We measured motor-evoked potentials in tibialis anterior and soleus muscles using transcranial magnetic stimulation under the following conditions: (1) baseline, (2) action observation (AO), and (3) AO and MI. Our results showed that, compared with AO alone, AO and MI of walking increased motor-evoked potentials. Our results suggest that CSE may be facilitated during AO and MI of walking, rather than during AO alone. Further, we postulated that AO and MI of walking may facilitate CSE in the tibialis anterior in a manner such as that evoked during actual walking.
aDepartment of Life Science, Graduate School of Arts and Science, The University of Tokyo
bInstitute of Sports Medicine and Science, Tokyo International University
cJapan Society for the promotion of Science, Tokyo, Kawagoe, Japan
Correspondence to Kimitaka Nakazawa, PhD, Department of Life Science, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan Tel: +81 354 546 869; fax: +81 354 544 317; e-mail: email@example.com
Received October 10, 2017
Accepted October 31, 2017