About this item:

342 Views | 332 Downloads

Author Notes:

Corresponding author: J.L. Neva, Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Department of Physical Therapy, 212-2177 Westbrook Mall, Vancouver, BC V6T 1Z3, Canada. Fax: +1 604 822 1870. jason.neva@ubc.ca.

We thank the MS and control participants for volunteering for this study.

The decision to publish this article was solely the responsibility of the authors. All statements, opinions, and content presented in the published article are those of the authors and do not represent the opinions of Teva.

None of the authors have potential conflicts of interest to be disclosed.


Research Funding:

This study was supported by funding from Teva Canada Innovation.

JLN receives salary support from the Michael Smith Foundation for Health Research. BL receives salary support from the Heart and Stroke Foundation and the Michael Smith Foundation for Health Research. KEB and KPW received funding from the Natural Sciences and Engineering Research Council of Canada. CSM received funding from the Natural Sciences and Engineering Research Council of Canada, an IODE War Memorial Doctoral Scholarship and UBC Four year fellowship. CL is the recipient of the Women Against MS (WAMS) end MS Research and Training Network Transitional Career Development Award from the Multiple Sclerosis Society of Canada. ALM holds grants from the Natural Sciences and Engineering Research Council of Canada and the Multiple Sclerosis Society of Canada. LAB receives salary support from the Canada Research Chairs and the Michael Smith Foundation for Health Research.


  • Science & Technology
  • Life Sciences & Biomedicine
  • Behavioral Sciences
  • Neurosciences
  • Neurosciences & Neurology
  • Multiple sclerosis
  • Transcranial magnetic stimulation
  • Corticospinal excitability
  • Expanded disability status scale (EDSS)
  • Human
  • Brain

Multiple measures of corticospinal excitability are associated with clinical features of multiple sclerosis

Show all authors Show less authors


Journal Title:

Behavioural Brain Research


Volume 297


, Pages 187-195

Type of Work:

Article | Post-print: After Peer Review


In individuals with multiple sclerosis (MS), transcranial magnetic stimulation (TMS) may be employed to assess the integrity of corticospinal system and provides a potential surrogate biomarker of disability. The purpose of this study was to provide a comprehensive examination of the relationship between multiple measures corticospinal excitability and clinical disability in MS (expanded disability status scale (EDSS)). Bilateral corticospinal excitability was assessed using motor evoked potential (MEP) input-output (IO) curves, cortical silent period (CSP), short-interval intracortical inhibition (SICI), intracortical facilitation (ICF) and transcallosal inhibition (TCI) in 26 individuals with MS and 11 healthy controls. Measures of corticospinal excitability were compared between individuals with MS and controls. We evaluated the relationship(s) between age and clinical demographics such as age at MS onset (AO), disease duration (DD) and clinical disability (EDSS) with measures of corticospinal excitability. Corticospinal excitability thresholds were higher, MEP latency and CSP onset delayed and MEP durations prolonged in individuals with MS compared to controls. Age, DD and EDSS correlated with corticospinal excitability thresholds. Also, TCI duration and the linear slope of the MEP amplitude IO curve correlated with EDSS. Hierarchical regression modeling demonstrated that combining multiple TMS-based measures of corticospinal excitability accounted for unique variance in clinical disability (EDSS) beyond that of clinical demographics (AO, DD). Our results indicate that multiple TMS-based measures of corticospinal and interhemispheric excitability provide insights into the potential neural mechanisms associated with clinical disability in MS. These findings may aid in the clinical evaluation, disease monitoring and prediction of disability in MS.

Copyright information:

© 2015 Elsevier B.V.

This is an Open Access work distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Creative Commons License

Export to EndNote