Original article| Volume 93, ISSUE 11, P1987-1990, November 2012

“Virtual” Lesioning of the Human Oropharyngeal Motor Cortex: A Videofluoroscopic Study

Published:February 16, 2012DOI:


      Verin E, Michou E, Leroi A-M, Hamdy S, Marie J-P. “Virtual” lesioning of the human oropharyngeal motor cortex: a videofluoroscopic study.


      To use focal cortical inhibition and create a “virtual” lesion in the oropharyngeal motor cortex in healthy subjects to determine whether this provokes swallowing dysfunction.


      Intervention study: before and after cortical stimulation.


      Tertiary care center.


      Healthy adult volunteers (N=9; age range, 21–44y) participated in the study.


      Active or sham 1-Hz repetitive transcranial magnetic stimulation (rTMS) over the cortical sites in each hemisphere evoking the largest mylohyoid motor-evoked potentials (mMEPs) to single pulse transcranial magnetic stimulation.

      Main Outcome Measures

      Videofluoroscopic assessment was performed before and 5, 30, and 60 minutes after rTMS.


      The motor threshold was 83%±10% for the hemisphere with the larger mMEP (dominant) and 92%±9% for the hemisphere with the smaller mMEP (nondominant). When rTMS was performed over the dominant hemisphere, there was a decrease in oral transit time (P=.05), an increase in swallow reaction time (P=.0001), but no change of pharyngeal transit time or laryngeal closure duration. When rTMS was performed on the nondominant hemisphere, there was also a decrease in oral transit time (P=.05), but no change in any of the other swallowing measures. Neither active intervention produced any signs of aspiration or penetration. Sham stimulation had no effect.


      Inhibiting the human oropharyngeal motor cortex using rTMS transiently modifies swallowing behavior in a way reminiscent to that seen in stroke patients.

      Key Words

      List of Abbreviations:

      EMG (electromyogram), LCD (laryngeal closure duration), mMEP (mylohyoid motor-evoked potential), OTT (oral transit time), PTT (pharyngeal transit time), rTMS (repetitive transcranial magnetic stimulation), SRT (swallow response time)
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