Abstract
Verin E, Michou E, Leroi A-M, Hamdy S, Marie J-P. “Virtual” lesioning of the human
oropharyngeal motor cortex: a videofluoroscopic study.
Objective
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.
Design
Intervention study: before and after cortical stimulation.
Setting
Tertiary care center.
Participants
Healthy adult volunteers (N=9; age range, 21–44y) participated in the study.
Interventions
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.
Results
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.
Conclusions
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)To read this article in full you will need to make a payment
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Article info
Publication history
Published online: February 16, 2012
Footnotes
Supported by a local grant from Aides à Domicile aux Insuffisants Respiratoires (ADIR), Isneauville, France.
No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit on the authors or on any organization with which the authors are associated.
In-press corrected proof published online on Feb 14, 2012, at www.archives-pmr.org.
Identification
Copyright
© 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
