J L Neva1, K E Brown2, K P Wadden2, C S Mang2,3, M R Borich4, S K Meehan5, L A Boyd1,6. 1. Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada. 2. Graduate Studies in Rehabilitation Sciences, University of British Columbia, Vancouver Canada. 3. Division of Physical Medicine and Rehabilitation, Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Canada. 4. Department of Rehabilitation Medicine, Division of Physical Therapy, School of Medicine, Emory University, Atlanta, GA, USA. 5. School of Kinesiology, University of Michigan, Ann Arbor, Michigan, USA. 6. The Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada.
Abstract
BACKGROUND: In individuals with chronic stroke, impairment of the paretic arm may be exacerbated by increased contralesional transcallosal inhibition (TCI). Continuous theta burst stimulation (cTBS) can decrease primary motor cortex (M1) excitability and TCI. However, contralesional cTBS shows inconsistent effects after stroke. Variable effects of cTBS could stem from failure to pair stimulation with skilled motor practice or a focus of applying cTBS over M1. OBJECTIVE: Here, we investigated the effects of pairing cTBS with skilled practice on motor learning and arm function. We considered the differential effects of stimulation over two different brain regions: contralesional M1 (M1c) or contralesional primary somatosensory cortex (S1c). METHODS: 37 individuals with chronic stroke participated in five sessions of cTBS and paretic arm skilled practice of a serial targeting task (STT); participants received either cTBS over M1c or S1c or sham before STT practice. Changes in STT performance and Wolf Motor Function Test (WMFT) were assessed as primary outcomes. Assessment of bilateral corticospinal, intracortical excitability and TCI were secondary outcomes. RESULTS: cTBS over sensorimotor cortex did not improve STT performance and paretic WMFT-rate beyond sham cTBS. TCI was reduced bi-directionally following the intervention, regardless of stimulation group. In addition, we observed an association between STT performance change and paretic WMFT-rate change in the M1c stimulation group only. CONCLUSIONS: Multiple sessions of STT practice can improve paretic arm function and decrease TCI bilaterally, with no additional benefit of prior cTBS. Our results suggest that improvement in STT practice following M1c cTBS scaled with change in paretic arm function in some individuals. Our results highlight the need for a better understanding of the mechanisms of cTBS to effectively identify who may benefit from this form of brain stimulation.
BACKGROUND: In individuals with chronic stroke, impairment of the paretic arm may be exacerbated by increased contralesional transcallosal inhibition (TCI). Continuous theta burst stimulation (cTBS) can decrease primary motor cortex (M1) excitability and TCI. However, contralesional cTBS shows inconsistent effects after stroke. Variable effects of cTBS could stem from failure to pair stimulation with skilled motor practice or a focus of applying cTBS over M1. OBJECTIVE: Here, we investigated the effects of pairing cTBS with skilled practice on motor learning and arm function. We considered the differential effects of stimulation over two different brain regions: contralesional M1 (M1c) or contralesional primary somatosensory cortex (S1c). METHODS: 37 individuals with chronic stroke participated in five sessions of cTBS and paretic arm skilled practice of a serial targeting task (STT); participants received either cTBS over M1c or S1c or sham before STT practice. Changes in STT performance and Wolf Motor Function Test (WMFT) were assessed as primary outcomes. Assessment of bilateral corticospinal, intracortical excitability and TCI were secondary outcomes. RESULTS:cTBS over sensorimotor cortex did not improve STT performance and paretic WMFT-rate beyond sham cTBS. TCI was reduced bi-directionally following the intervention, regardless of stimulation group. In addition, we observed an association between STT performance change and paretic WMFT-rate change in the M1c stimulation group only. CONCLUSIONS: Multiple sessions of STT practice can improve paretic arm function and decrease TCI bilaterally, with no additional benefit of prior cTBS. Our results suggest that improvement in STT practice following M1ccTBS scaled with change in paretic arm function in some individuals. Our results highlight the need for a better understanding of the mechanisms of cTBS to effectively identify who may benefit from this form of brain stimulation.
Entities:
Keywords:
Stroke; continuous theta burst zzm321990stimulationzzm321990; motor function; skilled motor practice; transcallosal inhibition; transcranial magnetic stimulation
Authors: James R Carey; Huiqiong Deng; Bernadette T Gillick; Jessica M Cassidy; David C Anderson; Lei Zhang; William Thomas Journal: Restor Neurol Neurosci Date: 2014 Impact factor: 2.406
Authors: Cathrin M Buetefisch; Kate Pirog Revill; Linda Shuster; Benjamin Hines; Michael Parsons Journal: J Neurophysiol Date: 2014-05-21 Impact factor: 2.714
Authors: Cameron S Mang; Nicholas J Snow; Katie P Wadden; Kristin L Campbell; Lara A Boyd Journal: Med Sci Sports Exerc Date: 2016-12 Impact factor: 5.411
Authors: J L Neva; B Lakhani; K E Brown; K P Wadden; C S Mang; N H M Ledwell; M R Borich; I M Vavasour; C Laule; A L Traboulsee; A L MacKay; L A Boyd Journal: Behav Brain Res Date: 2015-10-20 Impact factor: 3.332
Authors: Jeffrey A Kleim; Theresa M Hogg; Penny M VandenBerg; Natalie R Cooper; Rochelle Bruneau; Michael Remple Journal: J Neurosci Date: 2004-01-21 Impact factor: 6.167
Authors: Jennifer K Ferris; Jason L Neva; Irene M Vavasour; Kaitlin J Attard; Brian Greeley; Kathryn S Hayward; Katie P Wadden; Alex L MacKay; Lara A Boyd Journal: Hum Brain Mapp Date: 2021-05-03 Impact factor: 5.038