Cameron S Mang1, Michael R Borich2, Sonia M Brodie3, Katlyn E Brown1, Nicholas J Snow1, Katie P Wadden1, Lara A Boyd4. 1. Graduate Program in Rehabilitation Sciences, Faculty of Medicine, University of British Columbia, Vancouver, Canada. 2. Division of Physical Therapy, School of Medicine, Emory University, Atlanta, USA. 3. Graduate Program in Neuroscience, Faculty of Medicine, University of British Columbia, Vancouver, Canada. 4. Graduate Program in Rehabilitation Sciences, Faculty of Medicine, University of British Columbia, Vancouver, Canada; Graduate Program in Neuroscience, Faculty of Medicine, University of British Columbia, Vancouver, Canada. Electronic address: lara.boyd@ubc.ca.
Abstract
OBJECTIVE: To examine the relationship of transcallosal pathway microstructure and transcallosal inhibition (TCI) with motor function and impairment in chronic stroke. METHODS: Diffusion-weighted magnetic resonance imaging and transcranial magnetic stimulation (TMS) data were collected from 24 participants with chronic stroke and 11 healthy older individuals. Post-stroke motor function (Wolf Motor Function Test) and level of motor impairment (Fugl-Meyer score) were evaluated. RESULTS: Fractional anisotropy (FA) of transcallosal tracts between prefrontal cortices and the mean amplitude decrease in muscle activity during the ipsilateral silent period evoked by TMS over the non-lesioned hemisphere (termed NL-iSPmean) were significantly associated with level of motor impairment and motor function after stroke (p<0.05). A regression model including age, post-stroke duration, lesion volume, lesioned corticospinal tract FA, transcallosal prefrontal tract FA and NL-iSPmean accounted for 84% of variance in motor impairment (p<0.01). Both transcallosal prefrontal tract FA (ΔR(2)=0.12, p=0.04) and NL-iSPmean (ΔR(2)=0.09, p=0.04) accounted for unique variance in motor impairment level. CONCLUSIONS: Prefrontal transcallosal tract microstructure and TCI are each uniquely associated with motor impairment in chronic stroke. SIGNIFICANCE: Utilizing a multi-modal approach to assess transcallosal pathways may improve our capacity to identify important neural substrates of motor impairment in the chronic phase of stroke.
OBJECTIVE: To examine the relationship of transcallosal pathway microstructure and transcallosal inhibition (TCI) with motor function and impairment in chronic stroke. METHODS: Diffusion-weighted magnetic resonance imaging and transcranial magnetic stimulation (TMS) data were collected from 24 participants with chronic stroke and 11 healthy older individuals. Post-stroke motor function (Wolf Motor Function Test) and level of motor impairment (Fugl-Meyer score) were evaluated. RESULTS: Fractional anisotropy (FA) of transcallosal tracts between prefrontal cortices and the mean amplitude decrease in muscle activity during the ipsilateral silent period evoked by TMS over the non-lesioned hemisphere (termed NL-iSPmean) were significantly associated with level of motor impairment and motor function after stroke (p<0.05). A regression model including age, post-stroke duration, lesion volume, lesioned corticospinal tract FA, transcallosal prefrontal tract FA and NL-iSPmean accounted for 84% of variance in motor impairment (p<0.01). Both transcallosal prefrontal tract FA (ΔR(2)=0.12, p=0.04) and NL-iSPmean (ΔR(2)=0.09, p=0.04) accounted for unique variance in motor impairment level. CONCLUSIONS: Prefrontal transcallosal tract microstructure and TCI are each uniquely associated with motor impairment in chronic stroke. SIGNIFICANCE: Utilizing a multi-modal approach to assess transcallosal pathways may improve our capacity to identify important neural substrates of motor impairment in the chronic phase of stroke.
Authors: Yin-Liang Lin; Kelsey A Potter-Baker; David A Cunningham; Manshi Li; Vishwanath Sankarasubramanian; John Lee; Stephen Jones; Ken Sakaie; Xiaofeng Wang; Andre G Machado; Ela B Plow Journal: Clin Neurophysiol Date: 2020-07-03 Impact factor: 3.708
Authors: Katie P Wadden; Todd S Woodward; Paul D Metzak; Katie M Lavigne; Bimal Lakhani; Angela M Auriat; Lara A Boyd Journal: Behav Brain Res Date: 2015-03-08 Impact factor: 3.332
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: Lara A Boyd; Kathryn S Hayward; Nick S Ward; Cathy M Stinear; Charlotte Rosso; Rebecca J Fisher; Alexandre R Carter; Alex P Leff; David A Copland; Leeanne M Carey; Leonardo G Cohen; D Michele Basso; Jane M Maguire; Steven C Cramer Journal: Int J Stroke Date: 2017-07 Impact factor: 5.266
Authors: Jacqueline A Palmer; Lewis A Wheaton; Whitney A Gray; Mary Alice Saltão da Silva; Steven L Wolf; Michael R Borich Journal: Neurorehabil Neural Repair Date: 2019-07-22 Impact factor: 3.919