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Altheyab A, Alqurashi H, England TJ, Phillips BE, Piasecki M. Cross-education of lower limb muscle strength following resistance exercise training in males and females: A systematic review and meta-analysis. Exp Physiol 2024. [PMID: 39235953 DOI: 10.1113/ep091881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Accepted: 08/12/2024] [Indexed: 09/07/2024]
Abstract
Cross-education describes the training of one limb that leads to performance enhancements in the contralateral untrained limb, driven by neural changes rather than muscle adaptation. In this systematic review and meta-analysis, we aimed to evaluate the efficacy of cross-education (vs. a control group) via resistance exercise training (RET) for improving muscle strength in the untrained lower limb of healthy males and females. A literature search from inception to September 2023 was conducted using MEDLINE (via PubMed), the Cochrane Library (CENTRAL), Web of Science (Core Database), Scopus, EBSCO-host, and Ovid-EMBASE. Independent screening, data extraction and quality assessment were conducted. The measured outcomes were change in one-repetition maximum (1-RM) load, maximum voluntary contraction (MVC), and concentric, eccentric and isometric peak torque. Change in muscle structure (pennation angle and muscle thickness) was also analysed. A total of 29 studies were included. The pooled effect size from the random-effects model shows that cross-education significantly increased 1-RM compared to the control group (standardised mean difference (SMD): 0.59, 95% CI: 0.22-0.97; P = 0.002). Cross-education also significantly improved MVC (SMD: 0.55, 95% CI: 0.16-0.94; P = 0.006), concentric (SMD: 0.61, 95% CI: 0.39-0.84; P < 0.00001), eccentric (SMD: 0.39, 95% CI: 0.13-0.64; P = 0.003) and isometric (SMD: 0.45, 95% CI: 0.26-0.64; P < 0.00001) peak torque, each compared to the control group. When RET was categorised as eccentric or concentric, subgroup analysis showed that only eccentric training was associated with significantly increased isometric peak torque via cross-education (SMD: 0.37, 95% CI: 0.13-0.61; P = 0.003) (concentric, SMD: 0.33, 95% CI: -0.09 to 0.74; P = 0.12). This systematic review and meta-analysis emphasise the potency of cross-education for improving lower limb muscle strength. These findings have potential implications for clinical situations of impaired unilateral limb function (e.g., limb-casting or stroke). Future work exploring the mechanisms facilitating these enhancements will help to develop optimised rehabilitation protocols.
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Affiliation(s)
- Abdulmajeed Altheyab
- Centre of Metabolism, Ageing and Physiology, MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research & National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, University of Nottingham, Derby, UK
- Faculty of College of Applied Medical Sciences, King Saud bin Abdulaziz University for Health Science, Riyadh, Saudi Arabia
| | - Helal Alqurashi
- Centre for Rehabilitation and Ageing Research, Academic Unit of Injury, Inflammation and Recovery Sciences, School of Medicine, University of Nottingham, Nottingham, UK
| | - Timothy J England
- Stroke Trials Unit, Academic Unit of Mental Health and Clinical Neuroscience, School of Medicine, University of Nottingham, Derby, UK
- Vascular Medicine, Division of Medical Sciences and Graduate Entry Medicine, University of Nottingham, Royal Derby Hospital Centre, Derby, UK
| | - Bethan E Phillips
- Centre of Metabolism, Ageing and Physiology, MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research & National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, University of Nottingham, Derby, UK
| | - Mathew Piasecki
- Centre of Metabolism, Ageing and Physiology, MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research & National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, University of Nottingham, Derby, UK
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Li Y, Chang J, Zhu K, Zhang S, Zuo J, Xie B, Ni H, Yao J, Xu Z, Bian S, Yan T, Wu X, Chen S, Jin W, Wang Y, Xu P, Song P, Wu Y, Shen C, Zhu J, Yu Y, Dong F. Contribution of changes in the spinal cord and brain to the onset and progression of hand clumsiness symptoms in cervical spondylotic myelopathy. J Neurosurg Spine 2024; 41:396-406. [PMID: 38905708 DOI: 10.3171/2024.4.spine231238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Accepted: 04/03/2024] [Indexed: 06/23/2024]
Abstract
OBJECTIVE Cervical spondylotic myelopathy (CSM) stands as the most prevalent form of spinal cord injury, frequently prompting various changes in both the brain and spinal cord. However, the precise nature of these changes within the brains and spinal cords of CSM patients experiencing hand clumsiness (HCL) symptoms has remained elusive. The authors aimed to scrutinize these alterations and explore potential links between these changes and the onset of HCL symptoms. METHODS Using the modified Japanese Orthopaedic Association (mJOA) scale, the authors classified CSM patients into two groups: those without HCL and those with HCL. The authors performed voxel-wise z-score transformation amplitude of low-frequency fluctuations (zALFF) and resting-state functional connectivity (FC) evaluations in the brain. Additionally, they used the Spinal Cord Toolbox to calculate the fractional anisotropy (FA) of spinal cord tracts. The analysis also encompassed an examination of the correlation of these measures with improvements in mJOA scores. RESULTS Significant disparities in zALFF values surfaced in the right calcarine, right cuneus, right precuneus, right middle occipital gyrus (MOG), right superior occipital gyrus (SOG), and right superior parietal gyrus (SPG) between healthy controls (HC), patients without HCL, and patients with HCL, primarily within the visual cortex. In the patient group, patients with HCL displayed reduced FC between the right calcarine, right MOG, right SOG, right SPG, right SFG, bilateral MFG, and left median cingulate and paracingulate gyri when compared with patients without HCL. Moreover, significant differences in FA values of the corticospinal tract (CST) and reticulospinal tract (REST) at the C2 level emerged among HC, patients without HCL, and patients with HCL. Notably, zALFF, FC, and FA values in specific brain regions and spinal cord tracts exhibited correlations with mJOA upper-extremity scores. Additionally, FA values of the CST and REST correlated with zALFF values in the right calcarine, right MOG, right SOG, and right SPG. CONCLUSIONS Alterations within brain regions associated with the visual cortex, the fronto-parietal-occipital attention network, and spinal cord pathways appear to play a substantial role in the emergence and progression of HCL symptoms. Furthermore, the existence of a potential connection between the spinal cord and the brain suggests that this link might be related to the clinical symptoms of CSM.
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Affiliation(s)
- Yan Li
- Departments of1Orthopedics
- 2Spine Surgery
| | | | - Kun Zhu
- Departments of1Orthopedics
- 2Spine Surgery
| | - Siya Zhang
- Departments of1Orthopedics
- 2Spine Surgery
- 4School of Basic Medical Sciences, Anhui Medical University, Hefei; and
| | - Junxun Zuo
- Departments of1Orthopedics
- 2Spine Surgery
| | | | - Haoyu Ni
- Departments of1Orthopedics
- 2Spine Surgery
| | - Jiyuan Yao
- Departments of1Orthopedics
- 2Spine Surgery
| | - Zhibin Xu
- Departments of1Orthopedics
- 2Spine Surgery
| | | | | | | | - Senlin Chen
- 6Department of Orthopedics, Dongcheng Branch of The First Affiliated Hospital of Anhui Medical University (Feidong People's Hospital), Hefei, China
| | | | | | - Peng Xu
- Departments of1Orthopedics
- 2Spine Surgery
| | | | - Yuanyuan Wu
- 5Medical Imaging, The First Affiliated Hospital of Anhui Medical University, Hefei
| | | | | | | | - Fulong Dong
- Departments of1Orthopedics
- 2Spine Surgery
- 4School of Basic Medical Sciences, Anhui Medical University, Hefei; and
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Xu J, Mawase F, Schieber MH. Evolution, biomechanics, and neurobiology converge to explain selective finger motor control. Physiol Rev 2024; 104:983-1020. [PMID: 38385888 DOI: 10.1152/physrev.00030.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 01/16/2024] [Accepted: 02/15/2024] [Indexed: 02/23/2024] Open
Abstract
Humans use their fingers to perform a variety of tasks, from simple grasping to manipulating objects, to typing and playing musical instruments, a variety wider than any other species. The more sophisticated the task, the more it involves individuated finger movements, those in which one or more selected fingers perform an intended action while the motion of other digits is constrained. Here we review the neurobiology of such individuated finger movements. We consider their evolutionary origins, the extent to which finger movements are in fact individuated, and the evolved features of neuromuscular control that both enable and limit individuation. We go on to discuss other features of motor control that combine with individuation to create dexterity, the impairment of individuation by disease, and the broad extent of capabilities that individuation confers on humans. We comment on the challenges facing the development of a truly dexterous bionic hand. We conclude by identifying topics for future investigation that will advance our understanding of how neural networks interact across multiple regions of the central nervous system to create individuated movements for the skills humans use to express their cognitive activity.
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Affiliation(s)
- Jing Xu
- Department of Kinesiology, University of Georgia, Athens, Georgia, United States
| | - Firas Mawase
- Department of Biomedical Engineering, Israel Institute of Technology, Haifa, Israel
| | - Marc H Schieber
- Departments of Neurology and Neuroscience, University of Rochester, Rochester, New York, United States
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Shen T, Zhang W, Wang X, Ren X. Application of"Spinal cord fusion" in spinal cord injury repair and its neurological mechanism. Heliyon 2024; 10:e29422. [PMID: 38638967 PMCID: PMC11024622 DOI: 10.1016/j.heliyon.2024.e29422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 04/03/2024] [Accepted: 04/08/2024] [Indexed: 04/20/2024] Open
Abstract
Spinal cord injury (SCI) is a severely disabling and catastrophic condition that poses significant global clinical challenges. The difficulty of SCI repair results from the distinctive pathophysiological mechanisms, which are characterised by limited regenerative capacity and inadequate neuroplasticity of the spinal cord. Additionally, the formation of cystic cavities and astrocytic scars after SCI further obstructs both the ascending and descending neural conduction pathways. Consequently, the urgent challenge in post-SCI recovery lies in repairing the damaged spinal cord to reconstruct a functional and intact neural conduction circuit. In recent years, significant advancements in biological tissue engineering technology and novel therapies have resulted in a transformative shift in the field of SCI repair. Currently, SCI treatment primarily involves drug therapy, stem cell therapy, the use of biological materials, growth factors, and other approaches. This paper comprehensively reviews the progress in SCI research over the years, with a particular focus on the concept of "Spinal Cord Fusion" as a promising technique for SCI reconstruction. By discussing this important research progress and the neurological mechanisms involved, our aim is to help solve the problem of SCI repair as soon as possible and to bring new breakthroughs in the treatment of paraplegia after SCI.
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Affiliation(s)
- Tingting Shen
- Guangxi University of Chinese Medicine, Nanning, Guangxi, 530001, China
- Department of Orthopedics, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, 530011, China
- Institute of Orthopedics, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, 530011, China
- Global Initiative to Cure Paralysis (GICUP Alliance), Columbus, OH, 43221, United States
| | - Weihua Zhang
- Department of Orthopedics, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, 530011, China
- Institute of Orthopedics, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, 530011, China
- Global Initiative to Cure Paralysis (GICUP Alliance), Columbus, OH, 43221, United States
| | - Xiaogang Wang
- Guangxi University of Chinese Medicine, Nanning, Guangxi, 530001, China
- Department of Orthopedics, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, 530011, China
- Institute of Orthopedics, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, 530011, China
- Global Initiative to Cure Paralysis (GICUP Alliance), Columbus, OH, 43221, United States
| | - Xiaoping Ren
- Department of Orthopedics, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, 530011, China
- Institute of Orthopedics, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, 530011, China
- Global Initiative to Cure Paralysis (GICUP Alliance), Columbus, OH, 43221, United States
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Chen B, Tan Q, Zhang H, Chu W, Wen H, Tian X, Yang Y, Li W, Li W, Chen Y, Feng H. Contralesional Anodal Transcranial Direct Current Stimulation Promotes Intact Corticospinal Tract Axonal Sprouting and Functional Recovery After Traumatic Brain Injury in Mice. Neurorehabil Neural Repair 2024; 38:214-228. [PMID: 38385458 DOI: 10.1177/15459683241233261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
BACKGROUND Anodal transcranial direct current stimulation (AtDCS), a neuromodulatory technique, has been applied to treat traumatic brain injury (TBI) in patients and was reported to promote functional improvement. We evaluated the effect of contralesional AtDCS on axonal sprouting of the intact corticospinal tract (CST) and the underlying mechanism in a TBI mouse model to provide more preclinical evidence for the use of AtDCS to treat TBI. METHODS TBI was induced in mice by a contusion device. Then, the mice were subjected to contralesional AtDCS 5 days per week followed by a 2-day interval for 7 weeks. After AtDCS, motor function was evaluated by the irregular ladder walking, narrow beam walking, and open field tests. CST sprouting was assessed by anterograde and retrograde labeling of corticospinal neurons (CSNs), and the effect of AtDCS was further validated by pharmacogenetic inhibition of axonal sprouting using clozapine-N-oxide (CNO). RESULTS TBI resulted in damage to the ipsilesional cortex, while the contralesional CST remained intact. AtDCS improved the skilled motor functions of the impaired hindlimb in TBI mice by promoting CST axon sprouting, specifically from the intact hemicord to the denervated hemicord. Furthermore, electrical stimulation of CSNs significantly increased the excitability of neurons and thus activated the mechanistic target of rapamycin (mTOR) pathway. CONCLUSIONS Contralesional AtDCS improved skilled motor following TBI, partly by promoting axonal sprouting through increased neuronal activity and thus activation of the mTOR pathway.
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Affiliation(s)
- Beike Chen
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
- Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
- Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Qiang Tan
- Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
- Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
- Department of Blood Transfusion, The General Hospital of Western Theater Command, Chengdu, Sichuan Province, China
| | - Hongyan Zhang
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
- Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
- Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Weihua Chu
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
- Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
- Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Huizhong Wen
- Department of Neurobiology, College of Basic Medical Science, Third Military Medical University (Army Medical University), Chongqing, China
| | - Xuelong Tian
- College of Bioengineering, Chongqing University, Chongqing, China
| | - Yang Yang
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
- Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
- Department of Neurosurgery, The 904th Hospital of PLA, School of Medicine of Anhui Medical University, Wuxi, Jiangsu Province, China
| | - Weina Li
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
- Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
- Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Wenyan Li
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
- Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
- Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Yujie Chen
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
- Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
- Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Hua Feng
- Department of Neurosurgery and State Key Laboratory of Trauma, Burn and Combined Injury, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
- Chongqing Clinical Research Center for Neurosurgery, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
- Chongqing Key Laboratory of Precision Neuromedicine and Neuroregenaration, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
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Jung Y, Breitbart S, Malvea A, Bhatia A, Ibrahim GM, Gorodetsky C. Epidural Spinal Cord Stimulation for Spasticity: a Systematic Review of the Literature. World Neurosurg 2024; 183:227-238.e5. [PMID: 38181878 DOI: 10.1016/j.wneu.2023.12.158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 12/29/2023] [Accepted: 12/30/2023] [Indexed: 01/07/2024]
Abstract
OBJECTIVE Spasticity is a form of muscle hypertonia secondary to various diseases, including traumatic brain injury, spinal cord injury, cerebral palsy, and multiple sclerosis. Medical treatments are available; however, these often result in insufficient clinical response. This review evaluates the role of epidural spinal cord stimulation (SCS) in the treatment of spasticity and associated functional outcomes. METHODS A systematic review of the literature was performed using the Embase, CENTRAL, and MEDLINE databases. We included studies that used epidural SCS to treat spasticity. Studies investigating functional electric stimulation, transcutaneous SCS, and animal models of spasticity were excluded. We also excluded studies that used SCS to treat other symptoms such as pain. RESULTS Thirty-four studies were included in the final analysis. The pooled rate of subjective improvement in spasticity was 78% (95% confidence interval, 64%-91%; I2 = 77%), 40% (95% confidence interval, 7%-73%; I2 = 88%) for increased H-reflex threshold or decreased Hoffman reflex/muscle response wave ratio, and 73% (65%-80%; I2 = 50%) for improved ambulation. Patients with spinal causes had better outcomes compared with patients with cerebral causes. Up to 10% of patients experienced complications including infections and hardware malfunction. CONCLUSIONS Our review of the literature suggests that SCS may be a safe and useful tool for the management of spasticity; however, there is significant heterogeneity among studies. The quality of studies is also low. Further studies are needed to fully evaluate the usefulness of this technology, including various stimulation paradigms across different causes of spasticity.
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Affiliation(s)
- Youngkyung Jung
- Division of Neurosurgery, University of Toronto, Toronto, Ontario, Canada.
| | - Sara Breitbart
- Division of Neurosurgery, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Anahita Malvea
- Division of Neurosurgery, University of Toronto, Toronto, Ontario, Canada
| | - Anuj Bhatia
- Department of Anesthesia and Pain Medicine, University of Toronto and Toronto Western Hospital, Toronto, Ontario, Canada; Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada
| | - George M Ibrahim
- Division of Neurosurgery, University of Toronto, Toronto, Ontario, Canada; Division of Neurosurgery, Hospital for Sick Children, Toronto, Ontario, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Carolina Gorodetsky
- Division of Neurology, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada
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7
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Huang L, Yi L, Huang H, Zhan S, Chen R, Yue Z. Corticospinal tract: a new hope for the treatment of post-stroke spasticity. Acta Neurol Belg 2024; 124:25-36. [PMID: 37704780 PMCID: PMC10874326 DOI: 10.1007/s13760-023-02377-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 08/30/2023] [Indexed: 09/15/2023]
Abstract
Stroke is the third leading cause of death and disability worldwide. Post-stroke spasticity (PSS) is the most common complication of stroke but represents only one of the many manifestations of upper motor neuron syndrome. As an upper motor neuron, the corticospinal tract (CST) is the only direct descending motor pathway that innervates the spinal motor neurons and is closely related to the recovery of limb function in patients with PSS. Therefore, promoting axonal remodeling in the CST may help identify new therapeutic strategies for PSS. In this review, we outline the pathological mechanisms of PSS, specifically their relationship with CST, and therapeutic strategies for axonal regeneration of the CST after stroke. We found it to be closely associated with astroglial scarring produced by astrocyte activation and its secretion of neurotrophic factors, mainly after the onset of cerebral ischemia. We hope that this review offers insight into the relationship between CST and PSS and provides a basis for further studies.
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Affiliation(s)
- Linxing Huang
- College of Acupuncture, Massage and Rehabilitation, Hunan University of Chinese Medicine, Changsha, 410208, China
| | - Lizhen Yi
- College of Acupuncture, Massage and Rehabilitation, Hunan University of Chinese Medicine, Changsha, 410208, China
| | - Huiyuan Huang
- College of Acupuncture, Massage and Rehabilitation, Hunan University of Chinese Medicine, Changsha, 410208, China
| | - Sheng Zhan
- College of Acupuncture, Massage and Rehabilitation, Hunan University of Chinese Medicine, Changsha, 410208, China
| | - Ruixue Chen
- College of Acupuncture, Massage and Rehabilitation, Hunan University of Chinese Medicine, Changsha, 410208, China
| | - Zenghui Yue
- College of Acupuncture, Massage and Rehabilitation, Hunan University of Chinese Medicine, Changsha, 410208, China.
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8
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Winter CC, Jacobi A, Su J, Chung L, van Velthoven CTJ, Yao Z, Lee C, Zhang Z, Yu S, Gao K, Duque Salazar G, Kegeles E, Zhang Y, Tomihiro MC, Zhang Y, Yang Z, Zhu J, Tang J, Song X, Donahue RJ, Wang Q, McMillen D, Kunst M, Wang N, Smith KA, Romero GE, Frank MM, Krol A, Kawaguchi R, Geschwind DH, Feng G, Goodrich LV, Liu Y, Tasic B, Zeng H, He Z. A transcriptomic taxonomy of mouse brain-wide spinal projecting neurons. Nature 2023; 624:403-414. [PMID: 38092914 PMCID: PMC10719099 DOI: 10.1038/s41586-023-06817-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Accepted: 11/01/2023] [Indexed: 12/17/2023]
Abstract
The brain controls nearly all bodily functions via spinal projecting neurons (SPNs) that carry command signals from the brain to the spinal cord. However, a comprehensive molecular characterization of brain-wide SPNs is still lacking. Here we transcriptionally profiled a total of 65,002 SPNs, identified 76 region-specific SPN types, and mapped these types into a companion atlas of the whole mouse brain1. This taxonomy reveals a three-component organization of SPNs: (1) molecularly homogeneous excitatory SPNs from the cortex, red nucleus and cerebellum with somatotopic spinal terminations suitable for point-to-point communication; (2) heterogeneous populations in the reticular formation with broad spinal termination patterns, suitable for relaying commands related to the activities of the entire spinal cord; and (3) modulatory neurons expressing slow-acting neurotransmitters and/or neuropeptides in the hypothalamus, midbrain and reticular formation for 'gain setting' of brain-spinal signals. In addition, this atlas revealed a LIM homeobox transcription factor code that parcellates the reticulospinal neurons into five molecularly distinct and spatially segregated populations. Finally, we found transcriptional signatures of a subset of SPNs with large soma size and correlated these with fast-firing electrophysiological properties. Together, this study establishes a comprehensive taxonomy of brain-wide SPNs and provides insight into the functional organization of SPNs in mediating brain control of bodily functions.
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Affiliation(s)
- Carla C Winter
- F. M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
- Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
- PhD Program in Biological and Biomedical Sciences, Harvard Medical School, Boston, MA, USA
- Harvard-MIT MD-PhD Program, Harvard Medical School, Boston, MA, USA
| | - Anne Jacobi
- F. M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA.
- Department of Neurology, Harvard Medical School, Boston, MA, USA.
- Department of Ophthalmology, Harvard Medical School, Boston, MA, USA.
- F. Hoffman-La Roche, pRED, Basel, Switzerland.
| | - Junfeng Su
- F. M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
- Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Leeyup Chung
- F. M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
- Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | | | - Zizhen Yao
- Allen Institute for Brain Science, Seattle, WA, USA
| | - Changkyu Lee
- Allen Institute for Brain Science, Seattle, WA, USA
| | - Zicong Zhang
- F. M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
- Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Shuguang Yu
- F. M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
- Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Kun Gao
- Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
- Program in Neurogenetics, Department of Neurology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Geraldine Duque Salazar
- F. M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
- Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Evgenii Kegeles
- F. M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
- Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
- PhD Program in Biological and Biomedical Sciences, Harvard Medical School, Boston, MA, USA
| | - Yu Zhang
- F. M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
- Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Makenzie C Tomihiro
- F. M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
- Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Yiming Zhang
- F. M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
- Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Zhiyun Yang
- F. M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
- Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Junjie Zhu
- F. M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
- Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Jing Tang
- F. M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
- Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Xuan Song
- F. M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
- Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Ryan J Donahue
- F. M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Department of Neurology, Harvard Medical School, Boston, MA, USA
- Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Qing Wang
- Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
- Program in Neurogenetics, Department of Neurology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | | | | | - Ning Wang
- Allen Institute for Brain Science, Seattle, WA, USA
| | | | - Gabriel E Romero
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | - Michelle M Frank
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | - Alexandra Krol
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Riki Kawaguchi
- Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
- Program in Neurogenetics, Department of Neurology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Daniel H Geschwind
- Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
- Program in Neurogenetics, Department of Neurology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Guoping Feng
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Lisa V Goodrich
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | - Yuanyuan Liu
- Somatosensation and Pain Unit, National Institute of Dental and Craniofacial Research, National Center for Complementary and Integrative Health, National Institutes of Health, Bethesda, MD, USA
| | | | - Hongkui Zeng
- Allen Institute for Brain Science, Seattle, WA, USA.
| | - Zhigang He
- F. M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA.
- Department of Neurology, Harvard Medical School, Boston, MA, USA.
- Department of Ophthalmology, Harvard Medical School, Boston, MA, USA.
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9
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Akalu Y, Frazer AK, Howatson G, Pearce AJ, Siddique U, Rostami M, Tallent J, Kidgell DJ. Identifying the role of the reticulospinal tract for strength and motor recovery: A scoping review of nonhuman and human studies. Physiol Rep 2023; 11:e15765. [PMID: 37474275 PMCID: PMC10359156 DOI: 10.14814/phy2.15765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 06/26/2023] [Indexed: 07/22/2023] Open
Abstract
In addition to the established postural control role of the reticulospinal tract (RST), there has been an increasing interest on its involvement in strength, motor recovery, and other gross motor functions. However, there are no reviews that have systematically assessed the overall motor function of the RST. Therefore, we aimed to determine the role of the RST underpinning motor function and recovery. We performed a literature search using Ovid Medline, Embase, CINAHL Plus, and Scopus to retrieve papers using key words for RST, strength, and motor recovery. Human and animal studies which assessed the role of RST were included. Studies were screened and 32 eligible studies were included for the final analysis. Of these, 21 of them were human studies while the remaining were on monkeys and rats. Seven experimental animal studies and four human studies provided evidence for the involvement of the RST in motor recovery, while two experimental animal studies and eight human studies provided evidence for strength gain. The RST influenced gross motor function in two experimental animal studies and five human studies. Overall, the RST has an important role for motor recovery, gross motor function and at least in part, underpins strength gain. The role of RST for strength gain in healthy people and its involvement in spasticity in a clinical population has been limitedly described. Further studies are required to ascertain the role of the RST's role in enhancing strength and its contribution to the development of spasticity.
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Affiliation(s)
- Yonas Akalu
- Monash Exercise Neuroplasticity Research UnitDepartment of PhysiotherapySchool of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health ScienceMonash UniversityMelbourneVictoriaAustralia
- Department of Human PhysiologySchool of MedicineUniversity of GondarGondarEthiopia
| | - Ashlyn K. Frazer
- Monash Exercise Neuroplasticity Research UnitDepartment of PhysiotherapySchool of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health ScienceMonash UniversityMelbourneVictoriaAustralia
| | - Glyn Howatson
- Department of Sport, Exercise and RehabilitationNorthumbria UniversityNewcastleUK
- Water Research GroupNorth West UniversityPotchefstroomSouth Africa
| | - Alan J. Pearce
- College of Science, Health and EngineeringLa Trobe UniversityMelbourneVictoriaAustralia
| | - Ummatul Siddique
- Monash Exercise Neuroplasticity Research UnitDepartment of PhysiotherapySchool of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health ScienceMonash UniversityMelbourneVictoriaAustralia
| | - Mohamad Rostami
- Monash Exercise Neuroplasticity Research UnitDepartment of PhysiotherapySchool of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health ScienceMonash UniversityMelbourneVictoriaAustralia
| | - Jamie Tallent
- Monash Exercise Neuroplasticity Research UnitDepartment of PhysiotherapySchool of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health ScienceMonash UniversityMelbourneVictoriaAustralia
- School of Sport, Rehabilitation and Exercise SciencesUniversity of EssexColchesterUK
| | - Dawson J. Kidgell
- Monash Exercise Neuroplasticity Research UnitDepartment of PhysiotherapySchool of Primary and Allied Health Care, Faculty of Medicine, Nursing and Health ScienceMonash UniversityMelbourneVictoriaAustralia
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10
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Maslovat D, Santangelo CM, Carlsen AN. Startle-triggered responses indicate reticulospinal drive is larger for voluntary shoulder versus finger movements. Sci Rep 2023; 13:6532. [PMID: 37085607 PMCID: PMC10121700 DOI: 10.1038/s41598-023-33493-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 04/13/2023] [Indexed: 04/23/2023] Open
Abstract
Recent primate studies have implicated a substantial role of reticulospinal pathways in the production of various voluntary movements. A novel way to assess the relative reticulospinal contributions in humans is through the use of a "StartReact" paradigm where a startling acoustic stimulus (SAS) is presented during a simple reaction time (RT) task. The StartReact response is characterized by short-latency triggering of a prepared response, which is attributed to increased reticulospinal drive associated with startle reflex activation. The current study used a StartReact protocol to examine differences in reticulospinal contributions between proximal and distal effectors by examining EMG onset latencies in lateral deltoid and first dorsal interosseous during bilateral shoulder or finger abduction. The magnitude of the StartReact effect, and thus relative reticulospinal drive, was quantified as the difference in RT between startle trials in which startle-reflex related EMG activation in the sternocleidomastoid (SCM) was present (SCM +) versus absent (SCM -). A significantly larger StartReact effect was observed for bilateral shoulder abduction versus bimanual finger abduction and a higher incidence of SCM + trials occurred in the proximal task. Additionally, both startle reflex and response-related EMG measures were larger on SCM + trials for the shoulder versus finger task. These results provide compelling novel evidence for increased reticulospinal activation in bilateral proximal upper-limb movements.
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Affiliation(s)
- Dana Maslovat
- School of Human Kinetics, University of Ottawa, 125 University Private, Ottawa, ON, K1N 6N5, Canada
| | - Cassandra M Santangelo
- School of Human Kinetics, University of Ottawa, 125 University Private, Ottawa, ON, K1N 6N5, Canada
| | - Anthony N Carlsen
- School of Human Kinetics, University of Ottawa, 125 University Private, Ottawa, ON, K1N 6N5, Canada.
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11
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Buetefisch CM, Haut MW, Revill KP, Shaeffer S, Edwards L, Barany DA, Belagaje SR, Nahab F, Shenvi N, Easley K. Stroke Lesion Volume and Injury to Motor Cortex Output Determines Extent of Contralesional Motor Cortex Reorganization. Neurorehabil Neural Repair 2023; 37:119-130. [PMID: 36786394 PMCID: PMC10079613 DOI: 10.1177/15459683231152816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
BACKGROUND After stroke, increases in contralesional primary motor cortex (M1CL) activity and excitability have been reported. In pre-clinical studies, M1CL reorganization is related to the extent of ipsilesional M1 (M1IL) injury, but this has yet to be tested clinically. OBJECTIVES We tested the hypothesis that the extent of damage to the ipsilesional M1 and/or its corticospinal tract (CST) determines the magnitude of M1CL reorganization and its relationship to affected hand function in humans recovering from stroke. METHODS Thirty-five participants with a single subacute ischemic stroke affecting M1 or CST and hand paresis underwent MRI scans of the brain to measure lesion volume and CST lesion load. Transcranial magnetic stimulation (TMS) of M1IL was used to determine the presence of an electromyographic response (motor evoked potential (MEP+ and MEP-)). M1CL reorganization was determined by TMS applied to M1CL at increasing intensities. Hand function was quantified with the Jebsen Taylor Hand Function Test. RESULTS The extent of M1CL reorganization was related to greater lesion volume in the MEP- group, but not in the MEP+ group. Greater M1CL reorganization was associated with more impaired hand function in MEP- but not MEP+ participants. Absence of an MEP (MEP-), larger lesion volumes and higher lesion loads in CST, particularly in CST fibers originating in M1 were associated with greater impairment of hand function. CONCLUSIONS In the subacute post-stroke period, stroke volume and M1IL output determine the extent of M1CL reorganization and its relationship to affected hand function, consistent with pre-clinical evidence.ClinicalTrials.gov Identifier: NCT02544503.
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Affiliation(s)
- Cathrin M Buetefisch
- Department of Neurology, Emory University, Atlanta, GA, USA.,Department of Rehabilitation Medicine, Emory University, Atlanta, GA, USA
| | - Marc W Haut
- Department of Behavioral Medicine and Psychiatry, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV, USA.,Department of Neurology, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV, USA.,Department of Radiology, West Virginia University, Morgantown, WV, USA
| | - Kate P Revill
- Department of Psychology, Emory University, Atlanta, GA, USA
| | - Scott Shaeffer
- Department of Neurology, Emory University, Atlanta, GA, USA
| | - Lauren Edwards
- Department of Neurology, Emory University, Atlanta, GA, USA
| | | | - Samir R Belagaje
- Department of Neurology, Emory University, Atlanta, GA, USA.,Department of Rehabilitation Medicine, Emory University, Atlanta, GA, USA.,Marcus Stroke and Neuroscience Center, Grady Memorial Hospital, Atlanta, GA, USA
| | - Fadi Nahab
- Department of Neurology, Emory University, Atlanta, GA, USA
| | - Neeta Shenvi
- Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Kirk Easley
- Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, GA, USA
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12
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Srivastava S, Seamon BA, Marebwa BK, Wilmskoetter J, Bowden MG, Gregory CM, Seo NJ, Hanlon CA, Bonilha L, Brown TR, Neptune RR, Kautz SA. The relationship between motor pathway damage and flexion-extension patterns of muscle co-excitation during walking. Front Neurol 2022; 13:968385. [PMID: 36388195 PMCID: PMC9650203 DOI: 10.3389/fneur.2022.968385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 10/12/2022] [Indexed: 01/16/2023] Open
Abstract
Background Mass flexion-extension co-excitation patterns during walking are often seen as a consequence of stroke, but there is limited understanding of the specific contributions of different descending motor pathways toward their control. The corticospinal tract is a major descending motor pathway influencing the production of normal sequential muscle coactivation patterns for skilled movements. However, control of walking is also influenced by non-corticospinal pathways such as the corticoreticulospinal pathway that possibly contribute toward mass flexion-extension co-excitation patterns during walking. The current study sought to investigate the associations between damage to corticospinal (CST) and corticoreticular (CRP) motor pathways following stroke and the presence of mass flexion-extension patterns during walking as evaluated using module analysis. Methods Seventeen healthy controls and 44 stroke survivors were included in the study. We used non-negative matrix factorization for module analysis of paretic leg electromyographic activity. We typically have observed four modules during walking in healthy individuals. Stroke survivors often have less independently timed modules, for example two-modules presented as mass flexion-extension pattern. We used diffusion tensor imaging-based analysis where streamlines connecting regions of interest between the cortex and brainstem were computed to evaluate CST and CRP integrity. We also used a coarse classification tree analysis to evaluate the relative CST and CRP contribution toward module control. Results Interhemispheric CST asymmetry was associated with worse lower extremity Fugl-Meyer score (p = 0.023), propulsion symmetry (p = 0.016), and fewer modules (p = 0.028). Interhemispheric CRP asymmetry was associated with worse lower extremity Fugl-Meyer score (p = 0.009), Dynamic gait index (p = 0.035), Six-minute walk test (p = 0.020), Berg balance scale (p = 0.048), self-selected walking speed (p = 0.041), and propulsion symmetry (p = 0.001). The classification tree model reveled that substantial ipsilesional CRP or CST damage leads to a two-module pattern and poor walking ability with a trend toward increased compensatory contralesional CRP based control. Conclusion Both CST and CRP are involved with control of modules during walking and damage to both may lead to greater reliance on the contralesional CRP, which may contribute to a two-module pattern and be associated with worse walking performance.
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Affiliation(s)
- Shraddha Srivastava
- Ralph H. Johnson VA Medical Center, Charleston, SC, United States,Department of Health Sciences and Research, College of Health Professions, Medical University of South Carolina, Charleston, SC, United States,*Correspondence: Shraddha Srivastava
| | - Bryant A. Seamon
- Ralph H. Johnson VA Medical Center, Charleston, SC, United States,Department of Health Sciences and Research, College of Health Professions, Medical University of South Carolina, Charleston, SC, United States,Division of Physical Therapy, Department of Rehabilitation Sciences, College of Health Professions, Medical University of South Carolina, Charleston, SC, United States
| | - Barbara K. Marebwa
- Department of Neurology, College of Medicine, Medical University of South Carolina, Charleston, SC, United States
| | - Janina Wilmskoetter
- Department of Health Sciences and Research, College of Health Professions, Medical University of South Carolina, Charleston, SC, United States
| | - Mark G. Bowden
- Ralph H. Johnson VA Medical Center, Charleston, SC, United States,Department of Health Sciences and Research, College of Health Professions, Medical University of South Carolina, Charleston, SC, United States,Division of Physical Therapy, Department of Rehabilitation Sciences, College of Health Professions, Medical University of South Carolina, Charleston, SC, United States
| | - Chris M. Gregory
- Ralph H. Johnson VA Medical Center, Charleston, SC, United States,Department of Health Sciences and Research, College of Health Professions, Medical University of South Carolina, Charleston, SC, United States,Division of Physical Therapy, Department of Rehabilitation Sciences, College of Health Professions, Medical University of South Carolina, Charleston, SC, United States
| | - Na Jin Seo
- Ralph H. Johnson VA Medical Center, Charleston, SC, United States,Department of Health Sciences and Research, College of Health Professions, Medical University of South Carolina, Charleston, SC, United States,Division of Occupational Therapy, College of Health Professions, Medical University of South Carolina, Charleston, SC, United States
| | - Colleen A. Hanlon
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Leonardo Bonilha
- Department of Neurology, College of Medicine, Medical University of South Carolina, Charleston, SC, United States
| | - Truman R. Brown
- Department of Radiology and Radiological Science, College of Medicine, Medical University of South Carolina, Charleston, SC, United States
| | - Richard R. Neptune
- Walker Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX, United States
| | - Steven A. Kautz
- Ralph H. Johnson VA Medical Center, Charleston, SC, United States,Department of Health Sciences and Research, College of Health Professions, Medical University of South Carolina, Charleston, SC, United States,Division of Physical Therapy, Department of Rehabilitation Sciences, College of Health Professions, Medical University of South Carolina, Charleston, SC, United States
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13
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Boccuni L, Marinelli L, Trompetto C, Pascual-Leone A, Tormos Muñoz JM. Time to reconcile research findings and clinical practice on upper limb neurorehabilitation. Front Neurol 2022; 13:939748. [PMID: 35928130 PMCID: PMC9343948 DOI: 10.3389/fneur.2022.939748] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 06/27/2022] [Indexed: 11/13/2022] Open
Abstract
The problemIn the field of upper limb neurorehabilitation, the translation from research findings to clinical practice remains troublesome. Patients are not receiving treatments based on the best available evidence. There are certainly multiple reasons to account for this issue, including the power of habit over innovation, subjective beliefs over objective results. We need to take a step forward, by looking at most important results from randomized controlled trials, and then identify key active ingredients that determined the success of interventions. On the other hand, we need to recognize those specific categories of patients having the greatest benefit from each intervention, and why. The aim is to reach the ability to design a neurorehabilitation program based on motor learning principles with established clinical efficacy and tailored for specific patient's needs.Proposed solutionsThe objective of the present manuscript is to facilitate the translation of research findings to clinical practice. Starting from a literature review of selected neurorehabilitation approaches, for each intervention the following elements were highlighted: definition of active ingredients; identification of underlying motor learning principles and neural mechanisms of recovery; inferences from research findings; and recommendations for clinical practice. Furthermore, we included a dedicated chapter on the importance of a comprehensive assessment (objective impairments and patient's perspective) to design personalized and effective neurorehabilitation interventions.ConclusionsIt's time to reconcile research findings with clinical practice. Evidence from literature is consistently showing that neurological patients improve upper limb function, when core strategies based on motor learning principles are applied. To this end, practical take-home messages in the concluding section are provided, focusing on the importance of graded task practice, high number of repetitions, interventions tailored to patient's goals and expectations, solutions to increase and distribute therapy beyond the formal patient-therapist session, and how to integrate different interventions to maximize upper limb motor outcomes. We hope that this manuscript will serve as starting point to fill the gap between theory and practice in upper limb neurorehabilitation, and as a practical tool to leverage the positive impact of clinicians on patients' recovery.
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Affiliation(s)
- Leonardo Boccuni
- Institut Guttmann, Institut Universitari de Neurorehabilitació adscrit a la UAB, Badalona, Spain
- Universitat Autònoma de Barcelona, Bellaterra, Spain
- Fundació Institut d'Investigació en Ciències de la Salut Germans Trias i Pujol, Badalona, Spain
- *Correspondence: Leonardo Boccuni
| | - Lucio Marinelli
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genova, Genova, Italy
- IRCCS Ospedale Policlinico San Martino, Department of Neuroscience, Division of Clinical Neurophysiology, Genova, Italy
| | - Carlo Trompetto
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genova, Genova, Italy
- IRCCS Ospedale Policlinico San Martino, Department of Neuroscience, Division of Neurorehabilitation, Genova, Italy
| | - Alvaro Pascual-Leone
- Institut Guttmann, Institut Universitari de Neurorehabilitació adscrit a la UAB, Badalona, Spain
- Hinda and Arthur Marcus Institute for Aging Research and Deanna and Sidney Wolk Center for Memory Health, Hebrew SeniorLife, Boston, MA, United States
- Department of Neurology and Harvard Medical School, Boston, MA, United States
| | - José María Tormos Muñoz
- Institut Guttmann, Institut Universitari de Neurorehabilitació adscrit a la UAB, Badalona, Spain
- Universitat Autònoma de Barcelona, Bellaterra, Spain
- Fundació Institut d'Investigació en Ciències de la Salut Germans Trias i Pujol, Badalona, Spain
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14
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Boyne P, DiFrancesco M, Awosika OO, Williamson B, Vannest J. Mapping the human corticoreticular pathway with multimodal delineation of the gigantocellular reticular nucleus and high-resolution diffusion tractography. J Neurol Sci 2022; 434:120091. [PMID: 34979371 PMCID: PMC8957549 DOI: 10.1016/j.jns.2021.120091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 11/17/2021] [Accepted: 12/10/2021] [Indexed: 11/29/2022]
Abstract
The corticoreticular pathway (CRP) is a major motor tract that transmits cortical input to the reticular formation motor nuclei and may be an important mediator of motor recovery after central nervous system damage. However, its cortical origins, trajectory and laterality are incompletely understood in humans. This study aimed to map the human CRP and generate an average CRP template in standard MRI space. Following recently established guidelines, we manually delineated the primary reticular formation motor nucleus (gigantocellular reticular nucleus [GRN]) using several group-mean MRI contrasts from the Human Connectome Project (HCP). CRP tractography was then performed with HCP diffusion-weighted MRI data (N = 1065) by selecting diffusion streamlines that reached both the cortex and GRN. Corticospinal tract (CST) tractography was also performed for comparison. Results suggest that the human CRP has widespread origins, which overlap with the CST across most of the motor cortex and include additional exclusive inputs from the medial and anterior prefrontal cortices. The estimated CRP projected through the anterior and posterior limbs of the internal capsule before partially decussating in the midbrain tegmentum and converging bilaterally on the pontomedullary reticular formation. Thus, the CRP trajectory appears to partially overlap the CST, while being more distributed and anteromedial to the CST in the cerebrum before moving posterior to the CST in the brainstem. These findings have important implications for neurophysiologic testing, cortical stimulation and movement recovery after brain lesions. We expect that our GRN and tract maps will also facilitate future CRP research.
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Affiliation(s)
- Pierce Boyne
- Department of Rehabilitation, Exercise and Nutrition Sciences, College of Allied Health Sciences, University of Cincinnati, Cincinnati, OH 45267, USA.
| | - Mark DiFrancesco
- Department of Radiology and Pediatric Neuroimaging Research Consortium, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45267, USA
| | - Oluwole O Awosika
- Department of Neurology and Rehabilitation Medicine, College of Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Brady Williamson
- Department of Radiology, College of Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Jennifer Vannest
- Department of Communication Sciences and Disorders, College of Allied Health Sciences, University of Cincinnati, Cincinnati, OH 45267, USA
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15
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Williams PT, Truong DQ, Seifert AC, Xu J, Bikson M, Martin JH. Selective augmentation of corticospinal motor drive with trans-spinal direct current stimulation in the cat. Brain Stimul 2022; 15:624-634. [DOI: 10.1016/j.brs.2022.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 03/26/2022] [Accepted: 03/27/2022] [Indexed: 11/30/2022] Open
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16
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Abstract
The sudden loss of movement after spinal cord injury (SCI) is life-changing and is a major impetus to study spinal cord motor system plasticity and devise novel repair strategies. This review focuses on the motor cortex and the corticospinal tract, which are key to producing voluntary movements. The motor cortex projects directly to the spinal cord, via the corticospinal tract, and indirectly, via relays in the brain stem. With loss of the corticospinal tract after SCI, the indirect paths may bypass the injury and play an important role in voluntary control. In health and after injury, the spinal cord is a key site for activity-dependent neuroplasticity of the corticospinal system. Three kinds of activity-dependent plasticity have been identified: (1) corticospinal tract axon sprouting after electrical stimulation of the motor cortex; (2) synaptic competition between corticospinal tract and proprioceptive afferent fiber terminations; and (3) long-term potentiation (LTP) at the corticospinal tract-spinal interneuron synapse. SCI damages descending motor pathway connections and, in turn, triggers a loss of down-stream activity-dependent processes. This activity loss produces spinal interneuron degeneration and several activity-dependent maladaptive changes that underly hyperreflexia, spasticity, and spasms. Animal studies show that phasic electrical and tonic direct current stimulation can be used to supplement activity after SCI to reduce the activity-dependent degenerative and maladaptive changes. Importantly, when applied chronically neuromodulation recruits spinal neuroplasticity to improve function after SCI by promoting activity-dependent corticospinal axon sprouting and synapse formation. This helps establish new functional connections and strengthens spared connections. Combining neuromodulation to promote repair and motor rehabilitation to train circuits can most effectively promote motor recovery.
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Affiliation(s)
- John H Martin
- Department of Molecular, Cellular, and Biomedical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, United States; Neuroscience Program, Graduate Center of the City University of New York, New York, NY, United States.
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17
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Branscheidt M, Ejaz N, Xu J, Widmer M, Harran MD, Cortés JC, Kitago T, Celnik PA, Hernandez-Castillo C, Diedrichsen J, Luft AR, Krakauer JW. No evidence for motor recovery-related cortical connectivity changes after stroke using resting-state fMRI. J Neurophysiol 2021; 127:637-650. [PMID: 34965743 PMCID: PMC8896990 DOI: 10.1152/jn.00148.2021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
It has been proposed that a form of cortical reorganization (changes in functional connectivity between brain areas) can be assessed with resting-state (rs) fMRI. Here we report a longitudinal data-set collected from 19 patients with subcortical stroke and 11 controls. Patients were imaged up to five times over one year. We found no evidence, using rs-fMRI, for post-stroke cortical connectivity changes despite substantial behavioral recovery. These results could be construed as questioning the value of resting-state imaging. Here we argue instead that they are consistent with other emerging reasons to challenge the idea of motor recovery-related cortical reorganization post-stroke when conceived of as changes in connectivity between cortical areas.
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Affiliation(s)
- Meret Branscheidt
- Brain Physiology and Stimulation Laboratory, Department of Physical Medicine and Rehabilitation, Johns Hopkins University, Baltimore, MD, United States.,Department of Neurology, University Hospital Zurich, Zürich, Switzerland.,Cereneo Center for Neurology and Rehabilitation, Vitznau, Switzerland
| | - Naveed Ejaz
- Brain and Mind Institute, Western University, London, Ontario, Canada
| | - Jing Xu
- Department of Neuroscience, Johns Hopkins University, Baltimore, MD, United States.,Malone Center for Engineering in Healthcare, Johns Hopkins University, Baltimore, MD, United States
| | - Mario Widmer
- Department of Neurology, University Hospital Zurich, Zürich, Switzerland
| | - Michelle D Harran
- Department of Neuroscience, Johns Hopkins University, Baltimore, MD, United States
| | - Juan Camilo Cortés
- Department of Neurology, Johns Hopkins University, Baltimore, MD, United States
| | - Tomoko Kitago
- Burke Neurological Institute and Weill Cornell Medicine, White Plains, NY, United States
| | - Pablo A Celnik
- Brain Physiology and Stimulation Laboratory, Department of Physical Medicine and Rehabilitation, Johns Hopkins University, Baltimore, MD, United States
| | | | - Jörn Diedrichsen
- Brain and Mind Institute, Western University, London, Ontario, Canada
| | - Andreas R Luft
- Department of Neurology, University Hospital Zurich, Zürich, Switzerland.,Cereneo Center for Neurology and Rehabilitation, Vitznau, Switzerland
| | - John W Krakauer
- Department of Neuroscience, Johns Hopkins University, Baltimore, MD, United States.,Malone Center for Engineering in Healthcare, Johns Hopkins University, Baltimore, MD, United States.,Department of Neurology, Johns Hopkins University, Baltimore, MD, United States
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18
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Dixon TC, Merrick CM, Wallis JD, Ivry RB, Carmena JM. Hybrid dedicated and distributed coding in PMd/M1 provides separation and interaction of bilateral arm signals. PLoS Comput Biol 2021; 17:e1009615. [PMID: 34807905 PMCID: PMC8648118 DOI: 10.1371/journal.pcbi.1009615] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 12/06/2021] [Accepted: 11/04/2021] [Indexed: 01/23/2023] Open
Abstract
Pronounced activity is observed in both hemispheres of the motor cortex during preparation and execution of unimanual movements. The organizational principles of bi-hemispheric signals and the functions they serve throughout motor planning remain unclear. Using an instructed-delay reaching task in monkeys, we identified two components in population responses spanning PMd and M1. A “dedicated” component, which segregated activity at the level of individual units, emerged in PMd during preparation. It was most prominent following movement when M1 became strongly engaged, and principally involved the contralateral hemisphere. In contrast to recent reports, these dedicated signals solely accounted for divergence of arm-specific neural subspaces. The other “distributed” component mixed signals for each arm within units, and the subspace containing it did not discriminate between arms at any stage. The statistics of the population response suggest two functional aspects of the cortical network: one that spans both hemispheres for supporting preparatory and ongoing processes, and another that is predominantly housed in the contralateral hemisphere and specifies unilateral output. The motor cortex of the brain primarily controls the opposite side of the body, yet neural activity in this area is often observed during movements of either arm. To understand the functional significance of these signals we must first characterize how they are organized across the neural network. Are there patterns of activity that are unique to a single arm? Are there other patterns that reflect shared functions? Importantly, these features may change across time as motor plans are developed and executed. In this study, we analyzed the responses of individual neurons in the motor cortex and modeled their patterns of co-activity across the population to characterize the changes that distinguish left and right arm use. Across preparation and execution phases of the task, we found that signals became gradually more segregated. Despite many neurons modulating in association with either arm, those that were more dedicated to a single (typically contralateral) limb accounted for a disproportionately large amount of the variance. However, there were also weaker patterns of activity that did not distinguish between the two arms at any stage. These results reveal a heterogeneity in the motor cortex that highlights both independent and interactive components of reaching signals.
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Affiliation(s)
- Tanner C. Dixon
- UC Berkeley–UCSF Graduate Program in Bioengineering, University of California-Berkeley, Berkeley, California, United States of America
- * E-mail:
| | - Christina M. Merrick
- Department of Psychology, University of California-Berkeley, Berkeley, California, United States of America
| | - Joni D. Wallis
- UC Berkeley–UCSF Graduate Program in Bioengineering, University of California-Berkeley, Berkeley, California, United States of America
- Department of Psychology, University of California-Berkeley, Berkeley, California, United States of America
- Helen Wills Neuroscience Institute, University of California-Berkeley, Berkeley, California, United States of America
| | - Richard B. Ivry
- UC Berkeley–UCSF Graduate Program in Bioengineering, University of California-Berkeley, Berkeley, California, United States of America
- Department of Psychology, University of California-Berkeley, Berkeley, California, United States of America
- Helen Wills Neuroscience Institute, University of California-Berkeley, Berkeley, California, United States of America
| | - Jose M. Carmena
- UC Berkeley–UCSF Graduate Program in Bioengineering, University of California-Berkeley, Berkeley, California, United States of America
- Helen Wills Neuroscience Institute, University of California-Berkeley, Berkeley, California, United States of America
- Department of Electrical Engineering and Computer Sciences, University of California-Berkeley, Berkeley, California, United States of America
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19
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Calvert GHM, Carson RG. Neural mechanisms mediating cross education: With additional considerations for the ageing brain. Neurosci Biobehav Rev 2021; 132:260-288. [PMID: 34801578 DOI: 10.1016/j.neubiorev.2021.11.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 11/03/2021] [Accepted: 11/16/2021] [Indexed: 12/14/2022]
Abstract
CALVERT, G.H.M., and CARSON, R.G. Neural mechanisms mediating cross education: With additional considerations for the ageing brain. NEUROSCI BIOBEHAV REV 21(1) XXX-XXX, 2021. - Cross education (CE) is the process whereby a regimen of unilateral limb training engenders bilateral improvements in motor function. The contralateral gains thus derived may impart therapeutic benefits for patients with unilateral deficits arising from orthopaedic injury or stroke. Despite this prospective therapeutic utility, there is little consensus concerning its mechanistic basis. The precise means through which the neuroanatomical structures and cellular processes that mediate CE may be influenced by age-related neurodegeneration are also almost entirely unknown. Notwithstanding the increased incidence of unilateral impairment in later life, age-related variations in the expression of CE have been examined only infrequently. In this narrative review, we consider several mechanisms which may mediate the expression of CE with specific reference to the ageing CNS. We focus on the adaptive potential of cellular processes that are subserved by a specific set of neuroanatomical pathways including: the corticospinal tract, corticoreticulospinal projections, transcallosal fibres, and thalamocortical radiations. This analysis may inform the development of interventions that exploit the therapeutic utility of CE training in older persons.
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Affiliation(s)
- Glenn H M Calvert
- Trinity College Institute of Neuroscience and School of Psychology, Trinity College Dublin, Dublin, Ireland
| | - Richard G Carson
- Trinity College Institute of Neuroscience and School of Psychology, Trinity College Dublin, Dublin, Ireland; School of Psychology, Queen's University Belfast, Belfast, Northern Ireland, UK; School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, Australia.
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20
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Walker JR, Detloff MR. Plasticity in Cervical Motor Circuits following Spinal Cord Injury and Rehabilitation. BIOLOGY 2021; 10:biology10100976. [PMID: 34681075 PMCID: PMC8533179 DOI: 10.3390/biology10100976] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 09/17/2021] [Accepted: 09/22/2021] [Indexed: 11/16/2022]
Abstract
Simple Summary Spinal cord injury results in a decreased quality of life and impacts hundreds of thousands of people in the US alone. This review discusses the underlying cellular mechanisms of injury and the concurrent therapeutic hurdles that impede recovery. It then describes the phenomena of neural plasticity—the nervous system’s ability to change. The primary focus of the review is on the impact of cervical spinal cord injury on control of the upper limbs. The neural plasticity that occurs without intervention is discussed, which shows new connections growing around the injury site and the involvement of compensatory movements. Rehabilitation-driven neural plasticity is shown to have the ability to guide connections to create more normal functions. Various novel stimulation and recording technologies are outlined for their role in further improving rehabilitative outcomes and gains in independence. Finally, the importance of sensory input, an often-overlooked aspect of motor control, is shown in driving neural plasticity. Overall, this review seeks to delineate the historical and contemporary research into neural plasticity following injury and rehabilitation to guide future studies. Abstract Neuroplasticity is a robust mechanism by which the central nervous system attempts to adapt to a structural or chemical disruption of functional connections between neurons. Mechanical damage from spinal cord injury potentiates via neuroinflammation and can cause aberrant changes in neural circuitry known as maladaptive plasticity. Together, these alterations greatly diminish function and quality of life. This review discusses contemporary efforts to harness neuroplasticity through rehabilitation and neuromodulation to restore function with a focus on motor recovery following cervical spinal cord injury. Background information on the general mechanisms of plasticity and long-term potentiation of the nervous system, most well studied in the learning and memory fields, will be reviewed. Spontaneous plasticity of the nervous system, both maladaptive and during natural recovery following spinal cord injury is outlined to provide a baseline from which rehabilitation builds. Previous research has focused on the impact of descending motor commands in driving spinal plasticity. However, this review focuses on the influence of physical therapy and primary afferent input and interneuron modulation in driving plasticity within the spinal cord. Finally, future directions into previously untargeted primary afferent populations are presented.
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21
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Binder-Markey BI, Murray WM, Dewald JPA. Passive Properties of the Wrist and Fingers Following Chronic Hemiparetic Stroke: Interlimb Comparisons in Persons With and Without a Clinical Treatment History That Includes Botulinum Neurotoxin. Front Neurol 2021; 12:687624. [PMID: 34447346 PMCID: PMC8383209 DOI: 10.3389/fneur.2021.687624] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 07/02/2021] [Indexed: 11/13/2022] Open
Abstract
Background: Neural impairments that follow hemiparetic stroke may negatively affect passive muscle properties, further limiting recovery. However, factors such as hypertonia, spasticity, and botulinum neurotoxin (BoNT), a common clinical intervention, confound our understanding of muscle properties in chronic stroke. Objective: To determine if muscle passive biomechanical properties are different following prolonged, stroke-induced, altered muscle activation and disuse. Methods: Torques about the metacarpophalangeal and wrist joints were measured in different joint postures in both limbs of participants with hemiparetic stroke. First, we evaluated 27 participants with no history of BoNT; hand impairments ranged from mild to severe. Subsequently, seven participants with a history of BoNT injections were evaluated. To mitigate muscle hypertonia, torques were quantified after an extensive stretching protocol and under conditions that encouraged participants to sleep. EMGs were monitored throughout data collection. Results: Among participants who never received BoNT, no significant differences in passive torques between limbs were observed. Among participants who previously received BoNT injections, passive flexion torques about their paretic wrist and finger joints were larger than their non-paretic limb (average interlimb differences = +42.0 ± 7.6SEM Ncm, +26.9 ± 3.9SEM Ncm, respectively), and the range of motion for passive finger extension was significantly smaller (average interlimb difference = -36.3° ± 4.5°SEM; degrees). Conclusion: Our results suggest that neural impairments that follow chronic, hemiparetic stroke do not lead to passive mechanical changes within the wrist and finger muscles. Rather, consistent with animal studies, the data points to potential adverse effects of BoNT on passive muscle properties post-stroke, which warrant further consideration.
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Affiliation(s)
- Benjamin I Binder-Markey
- Department of Physical Therapy and Rehabilitation Sciences, Drexel University, Philadelphia, PA, United States.,School of Biomedical Engineering Science and Health Systems, Drexel University, Philadelphia, PA, United States.,Department of Biomedical Engineering, Northwestern University, Evanston, IL, United States.,Department of Physical Therapy and Human Movement Sciences, Northwestern University, Chicago, IL, United States.,Department of Physical Medicine and Rehabilitation Science, Northwestern University, Chicago, IL, United States.,Shirley Ryan Ability Lab, Chicago, IL, United States
| | - Wendy M Murray
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, United States.,Department of Physical Therapy and Human Movement Sciences, Northwestern University, Chicago, IL, United States.,Department of Physical Medicine and Rehabilitation Science, Northwestern University, Chicago, IL, United States.,Shirley Ryan Ability Lab, Chicago, IL, United States.,Research Service, Edward Hines Jr., VA Hospital, Hines, IL, United States
| | - Julius P A Dewald
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, United States.,Department of Physical Therapy and Human Movement Sciences, Northwestern University, Chicago, IL, United States.,Department of Physical Medicine and Rehabilitation Science, Northwestern University, Chicago, IL, United States
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22
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Hammerbeck U, Tyson SF, Samraj P, Hollands K, Krakauer JW, Rothwell J. The Strength of the Corticospinal Tract Not the Reticulospinal Tract Determines Upper-Limb Impairment Level and Capacity for Skill-Acquisition in the Sub-Acute Post-Stroke Period. Neurorehabil Neural Repair 2021; 35:812-822. [PMID: 34219510 PMCID: PMC8414832 DOI: 10.1177/15459683211028243] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background. Upper-limb impairment in patients with
chronic stroke appears to be partly attributable to an
upregulated reticulospinal tract (RST). Here, we assessed whether the impact of
corticospinal (CST) and RST connectivity on motor impairment and
skill-acquisition differs in sub-acute stroke, using
transcranial magnetic stimulation (TMS)–based proxy measures.
Methods. Thirty-eight stroke survivors were randomized to
either reach training 3-6 weeks post-stroke (plus usual care) or usual care
only. At 3, 6 and 12 weeks post-stroke, we measured ipsilesional and
contralesional cortical connectivity (surrogates for CST and RST connectivity,
respectively) to weak pre-activated triceps and deltoid muscles with single
pulse TMS, accuracy of planar reaching movements, muscle strength (Motricity
Index) and synergies (Fugl-Meyer upper-limb score). Results.
Strength and presence of synergies were associated with ipsilesional (CST)
connectivity to the paretic upper-limb at 3 and 12 weeks. Training led to planar
reaching skill beyond that expected from spontaneous recovery and occurred for
both weak and strong ipsilesional tract integrity. Reaching ability, presence of
synergies, skill-acquisition and strength were not affected by either the
presence or absence of contralesional (RST) connectivity.
Conclusion. The degree of ipsilesional CST connectivity is
the main determinant of proximal dexterity, upper-limb strength and synergy
expression in sub-acute stroke. In contrast, there is no evidence for enhanced
contralesional RST connectivity contributing to any of these components of
impairment. In the sub-acute post-stroke period, the balance of activity between
CST and RST may matter more for the paretic phenotype than RST upregulation per
se.
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Affiliation(s)
- Ulrike Hammerbeck
- Geoffrey Jefferson Brain Research Centre, 158986Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Healthy, 5292University of Manchester, Manchester, UK.,Department of Health Professions, Faculty of Health, Psychology and Social Care, 5289Manchester Metropolitan University, Manchester, UK
| | - Sarah F Tyson
- Department of Health Professions, Faculty of Health, Psychology and Social Care, 5289Manchester Metropolitan University, Manchester, UK
| | - Prawin Samraj
- Department of Medical Physics, Northern Care Alliance NHS Trust, Salford, UK
| | - Kristen Hollands
- Department of Health Sciences, 105168University of Salford, Salford, UK
| | - John W Krakauer
- Departments of Neurology, Neuroscience and Physical Medicine & Rehabilitation, 1500The John Hopkins University School of Medicine, Baltimore, MD, USA.,The Santa Fe Institute, Santa Fe, NM, USA
| | - John Rothwell
- Institute of Neurology, University College London, London, UK
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23
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Roby-Brami A, Jarrassé N, Parry R. Impairment and Compensation in Dexterous Upper-Limb Function After Stroke. From the Direct Consequences of Pyramidal Tract Lesions to Behavioral Involvement of Both Upper-Limbs in Daily Activities. Front Hum Neurosci 2021; 15:662006. [PMID: 34234659 PMCID: PMC8255798 DOI: 10.3389/fnhum.2021.662006] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 05/27/2021] [Indexed: 01/02/2023] Open
Abstract
Impairments in dexterous upper limb function are a significant cause of disability following stroke. While the physiological basis of movement deficits consequent to a lesion in the pyramidal tract is well demonstrated, specific mechanisms contributing to optimal recovery are less apparent. Various upper limb interventions (motor learning methods, neurostimulation techniques, robotics, virtual reality, and serious games) are associated with improvements in motor performance, but many patients continue to experience significant limitations with object handling in everyday activities. Exactly how we go about consolidating adaptive motor behaviors through the rehabilitation process thus remains a considerable challenge. An important part of this problem is the ability to successfully distinguish the extent to which a given gesture is determined by the neuromotor impairment and that which is determined by a compensatory mechanism. This question is particularly complicated in tasks involving manual dexterity where prehensile movements are contingent upon the task (individual digit movement, grasping, and manipulation…) and its objective (placing, two step actions…), as well as personal factors (motivation, acquired skills, and life habits…) and contextual cues related to the environment (presence of tools or assistive devices…). Presently, there remains a lack of integrative studies which differentiate processes related to structural changes associated with the neurological lesion and those related to behavioral change in response to situational constraints. In this text, we shall question the link between impairments, motor strategies and individual performance in object handling tasks. This scoping review will be based on clinical studies, and discussed in relation to more general findings about hand and upper limb function (manipulation of objects, tool use in daily life activity). We shall discuss how further quantitative studies on human manipulation in ecological contexts may provide greater insight into compensatory motor behavior in patients with a neurological impairment of dexterous upper-limb function.
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Affiliation(s)
- Agnès Roby-Brami
- ISIR Institute of Intelligent Systems and Robotics, AGATHE Team, CNRS UMR 7222, INSERM U 1150, Sorbonne University, Paris, France
| | - Nathanaël Jarrassé
- ISIR Institute of Intelligent Systems and Robotics, AGATHE Team, CNRS UMR 7222, INSERM U 1150, Sorbonne University, Paris, France
| | - Ross Parry
- ISIR Institute of Intelligent Systems and Robotics, AGATHE Team, CNRS UMR 7222, INSERM U 1150, Sorbonne University, Paris, France.,LINP2-AAPS Laboratoire Interdisciplinaire en Neurosciences, Physiologie et Psychologie: Activité Physique, Santé et Apprentissages, UPL, Paris Nanterre University, Nanterre, France
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24
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Mattos DJS, Rutlin J, Hong X, Zinn K, Shimony JS, Carter AR. White matter integrity of contralesional and transcallosal tracts may predict response to upper limb task-specific training in chronic stroke. NEUROIMAGE-CLINICAL 2021; 31:102710. [PMID: 34126348 PMCID: PMC8209270 DOI: 10.1016/j.nicl.2021.102710] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 05/25/2021] [Accepted: 05/26/2021] [Indexed: 11/19/2022]
Abstract
Increase in upper limb function post task specific training in chronic stroke. Motor improvements were not accompanied by changes in white matter integrity. Integrity in contralesional fibers predicted larger motor recovery in Responders. Non-responders had more severe damage of transcallosal fibers than Responders.
Objective To investigate white matter (WM) plasticity induced by intensive upper limb (UL) task specific training (TST) in chronic stroke. Methods Diffusion tensor imaging data and UL function measured by the Action Research Arm Test (ARAT) were collected in 30 individuals with chronic stroke prior to and after intensive TST. ANOVAs tested the effects of training on the entire sample and on the Responders [ΔARAT ≥ 5.8, N = 13] and Non-Responders [ΔARAT < 5.8, N = 17] groups. Baseline fractional anisotropy (FA) values were correlated with ARATpost TST controlling for baseline ARAT and age to identify voxels predictive of response to TST. Results. While ARAT scores increased following training (p < 0.0001), FA changes within major WM tracts were not significant at p < 0.05. In the Responder group, larger baseline FA of both contralesional (CL) and transcallosal tracts predicted larger ARAT scores post-TST. Subcortical lesions and more severe damage to transcallosal tracts were more pronounced in the Non-Responder than in the Responder group. Conclusions The motor improvements post-TST in the Responder group may reflect the engagement of interhemispheric processes not available to the Non-Responder group. Future studies should clarify differences in the role of CL and transcallosal pathways as biomarkers of recovery in response to training for individuals with cortical and subcortical stroke. This knowledge may help to identify sources of heterogeneity in stroke recovery, which is necessary for the development of customized rehabilitation interventions.
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Affiliation(s)
- Daniela J S Mattos
- Department of Neurology, Washington University School of Medicine, Saint Louis, MO 63110, USA.
| | - Jerrel Rutlin
- Department of Psychiatry, Washington University School of Medicine, Saint Louis, MO 63110, USA.
| | - Xin Hong
- Department of Genetics, Washington University School of Medicine, Saint Louis, MO 63110, USA.
| | - Kristina Zinn
- Department of Radiology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Joshua S Shimony
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, Saint Louis, MO 63110, USA.
| | - Alexandre R Carter
- Department of Neurology, Washington University School of Medicine, Saint Louis, MO 63110 USA.
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25
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Hoonhorst MHJ, Nijland RHM, Emmelot CH, Kollen BJ, Kwakkel G. TMS-Induced Central Motor Conduction Time at the Non-Infarcted Hemisphere Is Associated with Spontaneous Motor Recovery of the Paretic Upper Limb after Severe Stroke. Brain Sci 2021; 11:brainsci11050648. [PMID: 34063558 PMCID: PMC8157217 DOI: 10.3390/brainsci11050648] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 05/04/2021] [Accepted: 05/11/2021] [Indexed: 01/05/2023] Open
Abstract
Background: Stroke affects the neuronal networks of the non-infarcted hemisphere. The central motor conduction time (CMCT) induced by transcranial magnetic stimulation (TMS) could be used to determine the conduction time of the corticospinal tract of the non-infarcted hemisphere after a stroke. Objectives: Our primary aim was to demonstrate the existence of prolonged CMCT in the non-infarcted hemisphere, measured within the first 48 h when compared to normative data, and secondly, if the severity of motor impairment of the affected upper limb was significantly associated with prolonged CMCTs in the non-infarcted hemisphere when measured within the first 2 weeks post stroke. Methods: CMCT in the non-infarcted hemisphere was measured in 50 patients within 48 h and at 11 days after a first-ever ischemic stroke. Patients lacking significant spontaneous motor recovery, so-called non-recoverers, were defined as those who started below 18 points on the FM-UE and showed less than 6 points (10%) improvement within 6 months. Results: CMCT in the non-infarcted hemisphere was prolonged in 30/50 (60%) patients within 48 h and still in 24/49 (49%) patients at 11 days. Sustained prolonged CMCT in the non-infarcted hemisphere was significantly more frequent in non-recoverers following FM-UE. Conclusions: The current study suggests that CMCT in the non-infarcted hemisphere is significantly prolonged in 60% of severely affected, ischemic stroke patients when measured within the first 48 h post stroke. The likelihood of CMCT is significantly higher in non-recoverers when compared to those that show spontaneous motor recovery early post stroke.
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Affiliation(s)
| | - Rinske H. M. Nijland
- Amsterdam Rehabilitation Research Center|Reade, 1054 HW Amsterdam, The Netherlands;
| | - Cornelis H. Emmelot
- Department of Rehabilitation Medicine, Isala, 8025 AB Zwolle, The Netherlands;
| | - Boudewijn J. Kollen
- Department of General Practice and Elderly Care Medicine, University of Groningen, University Medical Center Groningen, 9712 CP Groningen, The Netherlands;
| | - Gert Kwakkel
- Amsterdam Rehabilitation Research Center|Reade, 1054 HW Amsterdam, The Netherlands;
- Amsterdam University Medical Center, Department of Rehabilitation Medicine, Amsterdam Movement Sciences, 1081 BT Amsterdam, The Netherlands
- Amsterdam Neurosciences, Amsterdam University Medical Centre, 1081 HV Amsterdam, The Netherlands
- Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University of Chicago, Evanston, IL 60208, USA
- Correspondence: ; Tel.: +31-204-441-940
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26
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Li XH, Zhu X, Liu XY, Xu HH, Jiang W, Wang JJ, Chen F, Zhang S, Li RX, Chen XY, Tu Y. The corticospinal tract structure of collagen/silk fibroin scaffold implants using 3D printing promotes functional recovery after complete spinal cord transection in rats. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2021; 32:31. [PMID: 33751254 PMCID: PMC7985105 DOI: 10.1007/s10856-021-06500-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 02/22/2021] [Indexed: 06/12/2023]
Abstract
No effective treatment has been established for nerve dysfunction caused by spinal cord injury (SCI). Orderly axonal growth at the site of spinal cord transection and creation of an appropriate biological microenvironment are important for functional recovery. To axially guiding axonal growth, designing a collagen/silk fibroin scaffold fabricated with 3D printing technology (3D-C/SF) emulated the corticospinal tract. The normal collagen/silk fibroin scaffold with freeze-drying technology (C/SF) or 3D-C/SF scaffold were implanted into rats with completely transected SCI to evaluate its effect on nerve repair during an 8-week observation period. Electrophysiological analysis and locomotor performance showed that the 3D-C/SF implants contributed to significant improvements in the neurogolical function of rats compared to C/SF group. By magnetic resonance imaging, 3D-C/SF implants promoted a striking degree of axonal regeneration and connection between the proximal and distal SCI sites. Compared with C/SF group, rats with 3D-C/SF scaffold exhibited fewer lesions and disordered structures in histological analysis and more GAP43-positive profiles at the lesion site. The above results indicated that the corticospinal tract structure of 3D printing collagen/silk fibroin scaffold improved axonal regeneration and promoted orderly connections within the neural network, which could provided a promising and innovative approach for tissue repair after SCI.
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Affiliation(s)
- Xiao-Hong Li
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, 300072, China
| | - Xiang Zhu
- Tianjin Key Laboratory of Neurotrauma Repair, Pingjin Hospital Brain Center, Characteristic Medical Center of PAPF, Tianjin, 300162, China
- Henan provincial people's hospital of southeast branch, Zhu ma dian, 463500, China
| | - Xiao-Yin Liu
- Tianjin Key Laboratory of Neurotrauma Repair, Pingjin Hospital Brain Center, Characteristic Medical Center of PAPF, Tianjin, 300162, China
- Tianjin Medical University, Tianjin, 300070, China
| | - Hai-Huan Xu
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, 300072, China
- Tianjin Key Laboratory of Neurotrauma Repair, Pingjin Hospital Brain Center, Characteristic Medical Center of PAPF, Tianjin, 300162, China
| | - Wei Jiang
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, 300072, China
| | - Jing-Jing Wang
- Tianjin Key Laboratory of Neurotrauma Repair, Pingjin Hospital Brain Center, Characteristic Medical Center of PAPF, Tianjin, 300162, China
| | - Feng Chen
- Tianjin Key Laboratory of Neurotrauma Repair, Pingjin Hospital Brain Center, Characteristic Medical Center of PAPF, Tianjin, 300162, China
| | - Sai Zhang
- Tianjin Key Laboratory of Neurotrauma Repair, Pingjin Hospital Brain Center, Characteristic Medical Center of PAPF, Tianjin, 300162, China
- Emergency Medical Center, Beijing Chaoyang Integrative medicine, Beijing, 100191, China
| | - Rui-Xin Li
- Central Laboratory, Tianjin Stomatological Hospital, Tianjin, 300041, China.
| | - Xu-Yi Chen
- Tianjin Key Laboratory of Neurotrauma Repair, Pingjin Hospital Brain Center, Characteristic Medical Center of PAPF, Tianjin, 300162, China.
| | - Yue Tu
- Tianjin Key Laboratory of Neurotrauma Repair, Pingjin Hospital Brain Center, Characteristic Medical Center of PAPF, Tianjin, 300162, China.
- Emergency Medical Center, Beijing Chaoyang Integrative medicine, Beijing, 100191, China.
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27
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Diabetes Mellitus-Related Dysfunction of the Motor System. Int J Mol Sci 2020; 21:ijms21207485. [PMID: 33050583 PMCID: PMC7589125 DOI: 10.3390/ijms21207485] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 10/08/2020] [Accepted: 10/08/2020] [Indexed: 12/20/2022] Open
Abstract
Although motor deficits in humans with diabetic neuropathy have been extensively researched, its effect on the motor system is thought to be lesser than that on the sensory system. Therefore, motor deficits are considered to be only due to sensory and muscle impairment. However, recent clinical and experimental studies have revealed that the brain and spinal cord, which are involved in the motor control of voluntary movement, are also affected by diabetes. This review focuses on the most important systems for voluntary motor control, mainly the cortico-muscular pathways, such as corticospinal tract and spinal motor neuron abnormalities. Specifically, axonal damage characterized by the proximodistal phenotype occurs in the corticospinal tract and motor neurons with long axons, and the transmission of motor commands from the brain to the muscles is impaired. These findings provide a new perspective to explain motor deficits in humans with diabetes. Finally, pharmacological and non-pharmacological treatment strategies for these disorders are presented.
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Collins AF, Brown STR, Baker MR. Minimum Electromyographic Burst Duration in Healthy Controls: Implications for Electrodiagnosis in Movement Disorders. Mov Disord Clin Pract 2020; 7:827-833. [PMID: 33033737 PMCID: PMC7533965 DOI: 10.1002/mdc3.13044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 07/09/2020] [Accepted: 07/24/2020] [Indexed: 11/29/2022] Open
Abstract
Background Electromyogram (EMG) burst duration can provide additional diagnostic information when investigating hyperkinetic movement disorders, particularly when a functional movement disorder is suspected. It is generally accepted that EMG bursts <50 milliseconds are pathological. Objective To reassess minimum physiological EMG burst duration. Methods Surface EMG was recorded from face, trunk, and limb muscles in controls (n = 60; ages 19–85). Participants were instructed to generate the briefest possible ballistic movements involving each muscle (40 repetitions) or, in muscles spanning joints, to generate rapid rhythmic alternating movements (20–30 seconds), or both. Results We found no effect of age on EMG burst duration. However, EMG burst duration varied significantly between body regions. Rhythmic EMG bursts were shorter than ballistic bursts but only significantly so for lower limbs (P < 0.001). EMG bursts of duration <50 milliseconds were frequently observed, particularly in appendicular muscles. Conclusion We present normal reference data for minimum EMG burst duration, which may assist clinical interpretation when investigating hyperkinetic movement disorders.
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Affiliation(s)
- Alexis F Collins
- Translational and Clinical Research Institute, The Medical School Newcastle University Newcastle upon Tyne United Kingdom.,Sheffield Institute for Translational Neuroscience The University of Sheffield Sheffield United Kingdom
| | - Steven T R Brown
- Translational and Clinical Research Institute, The Medical School Newcastle University Newcastle upon Tyne United Kingdom
| | - Mark R Baker
- Translational and Clinical Research Institute, The Medical School Newcastle University Newcastle upon Tyne United Kingdom.,Department of Neurology Royal Victoria Infirmary Newcastle upon Tyne United Kingdom.,Department of Clinical Neurophysiology Royal Victoria Infirmary Newcastle upon Tyne United Kingdom
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29
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Senesh MR, Barragan K, Reinkensmeyer DJ. Rudimentary Dexterity Corresponds With Reduced Ability to Move in Synergy After Stroke: Evidence of Competition Between Corticoreticulospinal and Corticospinal Tracts? Neurorehabil Neural Repair 2020; 34:904-914. [PMID: 32830602 PMCID: PMC7572533 DOI: 10.1177/1545968320943582] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVE When a stroke damages the corticospinal tract (CST), it has been hypothesized that the motor system switches to using the corticoreticulospinal tract (CRST) resulting in abnormal arm synergies. Is use of these tracts mutually exclusive, or can the motor system spontaneously switch between them depending on the type of movement it wants to make? If the motor system can share control at will, then people with a rudimentary ability to make dexterous movements should be able to perform synergistic arm movements as well. METHODS We analyzed clinical assessments of 319 persons' abilities to perform "out-of-synergy" and "in-synergy" arm movements after chronic stroke using the Upper Extremity Fugl-Meyer (UEFM) scale. RESULTS We identified a moderate range of arm impairment (UEFM = ~30-40) where subjects had a rudimentary ability to make out-of-synergy (~23%-50% on the out-of-synergy score) and dexterous hand movements (~3-10 blocks on Box and Blocks Test). Below this range persons could perform in-synergy but not out-of-synergy or dexterous movements. In the moderate range, however, scoring better on out-of-synergy movements correlated with scoring worse on in-synergy movements (P = .001, r ≈ -0.6). CONCLUSION Rudimentary dexterity corresponded with reduced ability to move the arm in-synergy. This finding supports the idea that CST and CRST compete and has implications for rehabilitation therapy.
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Abstract
Neuronal circuits that regulate movement are distributed throughout the nervous system. The brainstem is an important interface between upper motor centers involved in action planning and circuits in the spinal cord ultimately leading to execution of body movements. Here we focus on recent work using genetic and viral entry points to reveal the identity of functionally dedicated and frequently spatially intermingled brainstem populations essential for action diversification, a general principle conserved throughout evolution. Brainstem circuits with distinct organization and function control skilled forelimb behavior, orofacial movements, and locomotion. They convey regulatory parameters to motor output structures and collaborate in the construction of complex natural motor behaviors. Functionally tuned brainstem neurons for different actions serve as important integrators of synaptic inputs from upstream centers, including the basal ganglia and cortex, to regulate and modulate behavioral function in different contexts.
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Affiliation(s)
- Ludwig Ruder
- Biozentrum, Department of Cell Biology, University of Basel, 4056 Basel, Switzerland; .,Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland
| | - Silvia Arber
- Biozentrum, Department of Cell Biology, University of Basel, 4056 Basel, Switzerland; .,Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland
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31
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Irie S, Nakajima T, Suzuki S, Ariyasu R, Komiyama T, Ohki Y. Motor imagery enhances corticospinal transmission mediated by cervical premotoneurons in humans. J Neurophysiol 2020; 124:86-101. [DOI: 10.1152/jn.00574.2019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Imaging movement has positive effects on the reacquisition of motor functions after damage to the central nervous system. This study shows that motor imagery facilitates oligosynaptic corticospinal excitation that is mediated via cervical premotoneurons, which may be important for motor recovery in monkeys and humans. Current findings highlight how this imagery might be a beneficial tool for movement disorders through effects on premotoneuron circuitry.
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Affiliation(s)
- Shun Irie
- Department of Integrative Physiology, Kyorin University School of Medicine, Mitaka City, Tokyo, Japan
| | - Tsuyoshi Nakajima
- Department of Integrative Physiology, Kyorin University School of Medicine, Mitaka City, Tokyo, Japan
| | - Shinya Suzuki
- Department of Integrative Physiology, Kyorin University School of Medicine, Mitaka City, Tokyo, Japan
- Department of Physical Therapy, School of Rehabilitation Sciences, Health Sciences University of Hokkaido, Tobetsu-cho, Hokkaido, Japan
| | - Ryohei Ariyasu
- Department of Integrative Physiology, Kyorin University School of Medicine, Mitaka City, Tokyo, Japan
| | - Tomoyoshi Komiyama
- Division of Health and Sports Education, The United Graduate School of Education, Tokyo Gakugei University, Koganei City, Tokyo, Japan
- Division of Health and Sports Sciences, Faculty of Education, Chiba University, Chiba City, Chiba, Japan
| | - Yukari Ohki
- Department of Integrative Physiology, Kyorin University School of Medicine, Mitaka City, Tokyo, Japan
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Gallegos C, Carey M, Zheng Y, He X, Cao QL. Reaching and Grasping Training Improves Functional Recovery After Chronic Cervical Spinal Cord Injury. Front Cell Neurosci 2020; 14:110. [PMID: 32536855 PMCID: PMC7266985 DOI: 10.3389/fncel.2020.00110] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 04/08/2020] [Indexed: 12/31/2022] Open
Abstract
Previous studies suggest locomotion training could be an effective non-invasive therapy after spinal cord injury (SCI) using primarily acute thoracic injuries. However, the majority of SCI patients have chronic cervical injuries. Regaining hand function could significantly increase their quality of life. In this study, we used a clinically relevant chronic cervical contusion to study the therapeutic efficacy of rehabilitation in forelimb functional recovery. Nude rats received a moderate C5 unilateral contusive injury and were then divided into two groups with or without Modified Montoya Staircase (MMS) rehabilitation. For the rehabilitation group, rats were trained 5 days a week starting at 8 weeks post-injury (PI) for 6 weeks. All rats were assessed for skilled forelimb functions with MMS test weekly and for untrained gross forelimb locomotion with grooming and horizontal ladder (HL) tests biweekly. Our results showed that MMS rehabilitation significantly increased the number of pellets taken at 13 and 14 weeks PI and the accuracy rates at 12 to 14 weeks PI. However, there were no significant differences in the grooming scores or the percentage of HL missteps at any time point. Histological analyses revealed that MMS rehabilitation significantly increased the number of serotonergic fibers and the amount of presynaptic terminals around motor neurons in the cervical ventral horns caudal to the injury and reduced glial fibrillary acidic protein (GFAP)-immunoreactive astrogliosis in spinal cords caudal to the lesion. This study shows that MMS rehabilitation can modify the injury environment, promote axonal sprouting and synaptic plasticity, and importantly, improve reaching and grasping functions in the forelimb, supporting the therapeutic potential of task-specific rehabilitation for functional recovery after chronic SCI.
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Affiliation(s)
- Chrystine Gallegos
- The Vivian L. Smith Department of Neurosurgery, The University of Texas Health Science Center at Houston, Houston, TX, United States.,Center for Stem Cell and Regenerative Medicine, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Matthew Carey
- The Vivian L. Smith Department of Neurosurgery, The University of Texas Health Science Center at Houston, Houston, TX, United States.,Center for Stem Cell and Regenerative Medicine, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, The University of Texas Health Science Center at Houston, Houston, TX, United States.,Summer Undergraduate Research Program, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Yiyan Zheng
- The Vivian L. Smith Department of Neurosurgery, The University of Texas Health Science Center at Houston, Houston, TX, United States.,Center for Stem Cell and Regenerative Medicine, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Xiuquan He
- The Vivian L. Smith Department of Neurosurgery, The University of Texas Health Science Center at Houston, Houston, TX, United States.,Center for Stem Cell and Regenerative Medicine, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, The University of Texas Health Science Center at Houston, Houston, TX, United States.,Department of Anatomy and Histoembryology, School of Basic Medical Sciences, Shandong University, Jinan, China
| | - Qi Lin Cao
- The Vivian L. Smith Department of Neurosurgery, The University of Texas Health Science Center at Houston, Houston, TX, United States.,Center for Stem Cell and Regenerative Medicine, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, The University of Texas Health Science Center at Houston, Houston, TX, United States
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Choudhury S, Singh R, Shobhana A, Sen D, Anand SS, Shubham S, Gangopadhyay S, Baker MR, Kumar H, Baker SN. A Novel Wearable Device for Motor Recovery of Hand Function in Chronic Stroke Survivors. Neurorehabil Neural Repair 2020; 34:600-608. [PMID: 32452275 PMCID: PMC8207486 DOI: 10.1177/1545968320926162] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Background. In monkey, reticulospinal connections to hand and forearm muscles are spontaneously strengthened following corticospinal lesions, likely contributing to recovery of function. In healthy humans, pairing auditory clicks with electrical stimulation of a muscle induces plastic changes in motor pathways (probably including the reticulospinal tract), with features reminiscent of spike-timing dependent plasticity. In this study, we tested whether pairing clicks with muscle stimulation could improve hand function in chronic stroke survivors. Methods. Clicks were delivered via a miniature earpiece; transcutaneous electrical stimuli at motor threshold targeted forearm extensor muscles. A wearable electronic device (WD) allowed patients to receive stimulation at home while performing normal daily activities. A total of 95 patients >6 months poststroke were randomized to 3 groups: WD with shock paired 12 ms before click; WD with clicks and shocks delivered independently; standard care. Those allocated to the device used it for at least 4 h/d, every day for 4 weeks. Upper-limb function was assessed at baseline and weeks 2, 4, and 8 using the Action Research Arm Test (ARAT), which has 4 subdomains (Grasp, Grip, Pinch, and Gross). Results. Severity across the 3 groups was comparable at baseline. Only the paired stimulation group showed significant improvement in total ARAT (median baseline: 7.5; week 8: 11.5; P = .019) and the Grasp subscore (median baseline: 1; week 8: 4; P = .004). Conclusion. A wearable device delivering paired clicks and shocks over 4 weeks can produce a small but significant improvement in upper-limb function in stroke survivors.
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Affiliation(s)
| | - Ravi Singh
- Institute of Neurosciences, Kolkata, West Bengal, India
| | - A Shobhana
- Institute of Neurosciences, Kolkata, West Bengal, India
| | - Dwaipayan Sen
- Institute of Neurosciences, Kolkata, West Bengal, India
| | | | | | | | - Mark R Baker
- Newcastle University, Newcastle upon Tyne, Tyne and Wear, UK.,Royal Victoria Infirmary, Newcastle upon Tyne, Tyne and Wear, UK
| | | | - Stuart N Baker
- Newcastle University, Newcastle upon Tyne, Tyne and Wear, UK
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Wilkins KB, Dewald JPA, Yao J. Intervention-induced changes in neural connectivity during motor preparation may affect cortical activity at motor execution. Sci Rep 2020; 10:7326. [PMID: 32355238 PMCID: PMC7193567 DOI: 10.1038/s41598-020-64179-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 04/07/2020] [Indexed: 12/22/2022] Open
Abstract
Effective interventions have demonstrated the ability to improve motor function by reengaging ipsilesional resources, which appears to be critical and feasible for hand function recovery even in individuals with severe chronic stroke. However, previous studies focus on changes in brain activity related to motor execution. How changes in motor preparation may facilitate these changes at motor execution is still unclear. To address this question, 8 individuals with severe chronic hemiparetic stroke participated in a device-assisted intervention for seven weeks. We then quantified changes in both coupling between regions during motor preparation and changes in topographical cortical activity at motor execution for both hand opening in isolation and together with the shoulder using high-density EEG. We hypothesized that intervention-induced changes in cortico-cortico interactions during motor preparation would lead to changes in activity at motor execution specifically towards an increased reliance on the ipsilesional hemisphere. In agreement with this hypothesis, we found that, following the intervention, individuals displayed a reduction in coupling from ipsilesional M1 to contralesional M1 within gamma frequencies during motor preparation for hand opening. This was followed by a reduction in activity in the contralesional primary sensorimotor cortex during motor execution. Similarly, during lifting and opening, a shift to negative coupling within ipsilesional M1 from gamma to beta frequencies was accompanied by an increase in ipsilesional primary sensorimotor cortex activity following the intervention. Together, these results show that intervention-induced changes in coupling within or between motor regions during motor preparation may affect cortical activity at execution.
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Affiliation(s)
- Kevin B Wilkins
- Department of Physical Therapy and Human Movement Sciences, Northwestern University, 645 N Michigan Ave, Suite 1100, Chicago, IL, 60611, USA
- Northwestern University Interdepartmental Neuroscience, Northwestern University, 320 E. Superior St, Chicago, IL, 60611, USA
| | - Julius P A Dewald
- Department of Physical Therapy and Human Movement Sciences, Northwestern University, 645 N Michigan Ave, Suite 1100, Chicago, IL, 60611, USA
- Northwestern University Interdepartmental Neuroscience, Northwestern University, 320 E. Superior St, Chicago, IL, 60611, USA
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208, USA
- Department of Physical Medicine and Rehabilitation, Northwestern University, 345 East Superior Street, Chicago, IL, 60611, USA
| | - Jun Yao
- Department of Physical Therapy and Human Movement Sciences, Northwestern University, 645 N Michigan Ave, Suite 1100, Chicago, IL, 60611, USA.
- Northwestern University Interdepartmental Neuroscience, Northwestern University, 320 E. Superior St, Chicago, IL, 60611, USA.
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208, USA.
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35
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Wilkins KB, Yao J, Owen M, Karbasforoushan H, Carmona C, Dewald JPA. Limited capacity for ipsilateral secondary motor areas to support hand function post-stroke. J Physiol 2020; 598:2153-2167. [PMID: 32144937 DOI: 10.1113/jp279377] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Accepted: 02/21/2020] [Indexed: 12/31/2022] Open
Abstract
KEY POINTS Ipsilateral-projecting corticobulbar pathways, originating primarily from secondary motor areas, innervate the proximal and even distal portions, although they branch more extensively at the spinal cord. It is currently unclear to what extent these ipsilateral secondary motor areas and subsequent cortical projections may contribute to hand function following stroke-induced damage to one hemisphere. In the present study, we provide both structural and functional evidence indicating that individuals increasingly rely on ipsilateral secondary motor areas, although at the detriment of hand function. Increased activity in ipsilateral secondary motor areas was associated with increased involuntary coupling between shoulder abduction and finger flexion, most probably as a result of the low resolution of these pathways, making it increasingly difficult to open the hand. These findings suggest that, although ipsilateral secondary motor areas may support proximal movements, they do not have the capacity to support distal hand function, particularly for hand opening. ABSTRACT Recent findings have shown connections of ipsilateral cortico-reticulospinal tract (CRST), predominantly originating from secondary motor areas to not only proximal, but also distal muscles of the arm. Following a unilateral stroke, CRST from the ipsilateral side remains intact and thus has been proposed as a possible backup system for post-stroke rehabilitation even for the hand. We argue that, although CRST from ipsilateral secondary motor areas can provide control for proximal joints, it is insufficient to control either hand or coordinated shoulder and hand movements as a result of its extensive spinal branching compared to contralateral corticospinal tract. To address this issue, we combined magnetic resonance imaging, high-density EEG, and robotics in 17 individuals with severe chronic hemiparetic stroke and 12 age-matched controls. We tested for changes in structural morphometry of the sensorimotor cortex and found that individuals with stroke demonstrated higher grey matter density in secondary motor areas ipsilateral to the paretic arm compared to controls. We then measured cortical activity when participants were attempting to generate hand opening either supported on a table or when lifting against a shoulder abduction load. The addition of shoulder abduction during hand opening increased reliance on ipsilateral secondary motor areas in stroke, but not controls. Crucially, the increased use of ipsilateral secondary motor areas was associated with decreased hand opening ability when lifting the arm as a result of involuntary coupling between the shoulder and wrist/finger flexors. Taken together, this evidence implicates a compensatory role for ipsilateral (i.e. contralesional) secondary motor areas post-stroke, although with no apparent capacity to support hand function.
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Affiliation(s)
- Kevin B Wilkins
- Department of Physical Therapy and Human Movement Sciences, Northwestern University, 645 N Michigan Ave, Suite 1100, Chicago, IL, USA.,Northwestern University Interdepartmental Neuroscience, Northwestern University, 320 E. Superior St, Chicago, IL, USA
| | - Jun Yao
- Department of Physical Therapy and Human Movement Sciences, Northwestern University, 645 N Michigan Ave, Suite 1100, Chicago, IL, USA.,Northwestern University Interdepartmental Neuroscience, Northwestern University, 320 E. Superior St, Chicago, IL, USA.,Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL, USA
| | - Meriel Owen
- Department of Physical Therapy and Human Movement Sciences, Northwestern University, 645 N Michigan Ave, Suite 1100, Chicago, IL, USA.,Northwestern University Interdepartmental Neuroscience, Northwestern University, 320 E. Superior St, Chicago, IL, USA
| | - Haleh Karbasforoushan
- Department of Physical Therapy and Human Movement Sciences, Northwestern University, 645 N Michigan Ave, Suite 1100, Chicago, IL, USA.,Northwestern University Interdepartmental Neuroscience, Northwestern University, 320 E. Superior St, Chicago, IL, USA
| | - Carolina Carmona
- Department of Physical Therapy and Human Movement Sciences, Northwestern University, 645 N Michigan Ave, Suite 1100, Chicago, IL, USA
| | - Julius P A Dewald
- Department of Physical Therapy and Human Movement Sciences, Northwestern University, 645 N Michigan Ave, Suite 1100, Chicago, IL, USA.,Northwestern University Interdepartmental Neuroscience, Northwestern University, 320 E. Superior St, Chicago, IL, USA.,Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL, USA.,Department of Physical Medicine and Rehabilitation, Northwestern University, 345 East Superior Street, Chicago, IL, USA
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36
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Peyre I, Hanna-Boutros B, Lackmy-Vallee A, Kemlin C, Bayen E, Pradat-Diehl P, Marchand-Pauvert V. Music Restores Propriospinal Excitation During Stroke Locomotion. Front Syst Neurosci 2020; 14:17. [PMID: 32327977 PMCID: PMC7161673 DOI: 10.3389/fnsys.2020.00017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 03/10/2020] [Indexed: 11/24/2022] Open
Abstract
Music-based therapy for rehabilitation induces neuromodulation at the brain level and improves the functional recovery. In line with this, musical rhythmicity improves post-stroke gait. Moreover, an external distractor also helps stroke patients to improve locomotion. We raised the question whether music with irregular tempo (arrhythmic music), and its possible influence on attention would induce neuromodulation and improve the post-stroke gait. We tested music-induced neuromodulation at the level of a propriospinal reflex, known to be particularly involved in the control of stabilized locomotion; after stroke, the reflex is enhanced on the hemiparetic side. The study was conducted in 12 post-stroke patients and 12 controls. Quadriceps EMG was conditioned by electrical stimulation of the common peroneal nerve, which produces a biphasic facilitation on EMG, reflecting the level of activity of the propriospinal reflex between ankle dorsiflexors and quadriceps (CPQ reflex). The CPQ reflex was tested during treadmill locomotion at the preferred speed of each individual, in 3 conditions randomly alternated: without music vs. 2 arrhythmic music tracks, including a pleasant melody and unpleasant aleatory electronic sounds (AES); biomechanical and physiological parameters were also investigated. The CPQ reflex was significantly larger in patients during walking without sound, compared to controls. During walking with music, irrespective of the theme, there was no more difference between groups. In controls, music had no influence on the size of CPQ reflex. In patients, CPQ reflex was significantly larger during walking without sound than when listening to the melody or AES. No significant differences have been revealed concerning the biomechanical and the physiological parameters in both groups. Arrhythmic music listening modulates the spinal excitability during post-stroke walking, restoring the CPQ reflex activity to normality. The plasticity was not accompanied by any clear improvement of gait parameters, but the patients reported to prefer walking with music than without. The role of music as external focus of attention is discussed. This study has shown that music can modulate propriospinal neural network particularly involved in the gait control during the first training session. It is speculated that repetition may help to consolidate plasticity and would contribute to gait recovery after stroke.
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Affiliation(s)
- Iseline Peyre
- Sorbonne Université, Inserm, CNRS, Laboratoire d'Imagerie Biomédicale, LIB, Paris, France.,Sorbonne Université, CNRS, Institut de Recherche et de Coordination en Acoustique Musique (IRCAM), UMR Sciences et Technologies de la Musique et du Son (STMS), Paris, France
| | | | | | - Claire Kemlin
- Sorbonne Université, AP-HP, GRC n°24, Handicap Moteur et Cognitif & Réadaptation (HaMCRe), Paris, France
| | - Eléonore Bayen
- Sorbonne Université, AP-HP, GRC n°24, Handicap Moteur et Cognitif & Réadaptation (HaMCRe), Paris, France
| | - Pascale Pradat-Diehl
- Sorbonne Université, Inserm, CNRS, Laboratoire d'Imagerie Biomédicale, LIB, Paris, France.,Sorbonne Université, AP-HP, GRC n°24, Handicap Moteur et Cognitif & Réadaptation (HaMCRe), Paris, France
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Bao SC, Khan A, Song R, Kai-yu Tong R. Rewiring the Lesioned Brain: Electrical Stimulation for Post-Stroke Motor Restoration. J Stroke 2020; 22:47-63. [PMID: 32027791 PMCID: PMC7005350 DOI: 10.5853/jos.2019.03027] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 01/03/2020] [Accepted: 01/06/2020] [Indexed: 02/06/2023] Open
Abstract
Electrical stimulation has been extensively applied in post-stroke motor restoration, but its treatment mechanisms are not fully understood. Stimulation of neuromotor control system at multiple levels manipulates the corresponding neuronal circuits and results in neuroplasticity changes of stroke survivors. This rewires the lesioned brain and advances functional improvement. This review addresses the therapeutic mechanisms of different stimulation modalities, such as noninvasive brain stimulation, peripheral electrical stimulation, and other emerging techniques. The existing applications, the latest progress, and future directions are discussed. The use of electrical stimulation to facilitate post-stroke motor recovery presents great opportunities in terms of targeted intervention and easy applicability. Further technical improvements and clinical studies are required to reveal the neuromodulatory mechanisms and to enhance rehabilitation therapy efficiency in stroke survivors and people with other movement disorders.
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Affiliation(s)
- Shi-chun Bao
- Department of Biomedical Engineering, The Chinese University of Hong Kong, Hong Kong, China
| | - Ahsan Khan
- Department of Biomedical Engineering, The Chinese University of Hong Kong, Hong Kong, China
| | - Rong Song
- School of Biomedical Engineering, Sun Yat-Sen University, Guangzhou, China
| | - Raymond Kai-yu Tong
- Department of Biomedical Engineering, The Chinese University of Hong Kong, Hong Kong, China
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Maxwell DJ, Soteropoulos DS. The mammalian spinal commissural system: properties and functions. J Neurophysiol 2019; 123:4-21. [PMID: 31693445 DOI: 10.1152/jn.00347.2019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Commissural systems are essential components of motor circuits that coordinate left-right activity of the skeletomuscular system. Commissural systems are found at many levels of the neuraxis including the cortex, brainstem, and spinal cord. In this review we will discuss aspects of the mammalian spinal commissural system. We will focus on commissural interneurons, which project from one side of the cord to the other and form axonal terminations that are confined to the cord itself. Commissural interneurons form heterogeneous populations and influence a variety of spinal circuits. They can be defined according to a variety of criteria including, location in the spinal gray matter, axonal projections and targets, neurotransmitter phenotype, activation properties, and embryological origin. At present, we do not have a comprehensive classification of these cells, but it is clear that cells located within different areas of the gray matter have characteristic properties and make particular contributions to motor circuits. The contribution of commissural interneurons to locomotor function and posture is well established and briefly discussed. However, their role in other goal-orientated behaviors such as grasping, reaching, and bimanual tasks is less clear. This is partly because we only have limited information about the organization and functional properties of commissural interneurons in the cervical spinal cord of primates, including humans. In this review we shall discuss these various issues. First, we will consider the properties of commissural interneurons and subsequently examine what is known about their functions. We then discuss how they may contribute to restoration of function following spinal injury and stroke.
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Affiliation(s)
- David J Maxwell
- Spinal Cord Group, Institute of Neuroscience and Psychology, College of Medicine, Veterinary Medicine and Life Sciences, University of Glasgow, Glasgow, United Kingdom
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39
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Glover IS, Baker SN. Multimodal stimuli modulate rapid visual responses during reaching. J Neurophysiol 2019; 122:1894-1908. [DOI: 10.1152/jn.00158.2019] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The reticulospinal tract plays an important role in primate upper limb function, but methods for assessing its activity are limited. One promising approach is to measure rapid visual responses (RVRs) in arm muscle activity during a visually cued reaching task; these may arise from a tecto-reticulospinal pathway. We investigated whether changes in reticulospinal excitability can be assessed noninvasively using RVRs, by pairing the visual stimuli of the reaching task with electrical stimulation of the median nerve, galvanic vestibular stimulation, or loud sounds, all of which are known to activate the reticular formation. Surface electromyogram (EMG) recordings were made from the right deltoid of healthy human subjects as they performed fast reaching movements toward visual targets. Stimuli were delivered up to 200 ms before target appearance, and RVR was quantified as the EMG amplitude in a window 75–125 ms after visual target onset. Median nerve, vestibular, and auditory stimuli all consistently facilitated the RVRs, as well as reducing the latency of responses. We propose that this facilitation reflects modulation of tecto-reticulospinal excitability, which is consistent with the idea that the amplitude of RVRs can be used to assess changes in brain stem excitability noninvasively in humans. NEW & NOTEWORTHY Short-latency responses in arm muscles evoked during a visually driven reaching task have previously been proposed to be tecto-reticulospinal in origin. We demonstrate that these responses can be facilitated by pairing the appearance of a visual target with stimuli that activate the reticular formation: median nerve, vestibular, and auditory stimuli. We propose that this reflects noninvasive measurement and modulation of reticulospinal excitability.
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Affiliation(s)
- Isabel S. Glover
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Stuart N. Baker
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
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Wang H, Arceo R, Chen S, Ding L, Jia J, Yao J. Effectiveness of interventions to improve hand motor function in individuals with moderate to severe stroke: a systematic review protocol. BMJ Open 2019; 9:e032413. [PMID: 31562163 PMCID: PMC6773351 DOI: 10.1136/bmjopen-2019-032413] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
INTRODUCTION The human hand is extremely involved in our daily lives. However, the rehabilitation of hand function after stroke can be rather difficult due to the complexity of hand structure and function, as well as neural basis that supports hand function. Specifically, in individuals with moderate to severe impairment following a stroke, previous evidence for effective treatments that recover hand function in this population is limited, and thus has never been reviewed. With the progress of rehabilitation science and tool development, results from more and more clinical trials are now available, thereby justifying conducting a systematic review. METHODS AND ANALYSIS This systematic review protocol is consistent with the methodology recommended by the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols and the Cochrane handbook for systematic reviews of interventions. Electronic searches will be carried out in the PubMed, CINAHL, Physiotherapy Evidence Database and Cochrane Library databases, along with manual searches in the reference lists from included studies and published systematic reviews. The date range parameters used in searching all databases is between January 1999 and January 2019. Randomised controlled trials (RCTs) published in English, with the primary outcome focusing on hand motor function, will be included. Two reviewers will screen all retrieved titles, abstracts and full texts, perform the evaluation of the risk bias and extract all data independently. The risk of bias of the included RCTs will be evaluated by the Cochrane Collaboration's tool. A qualitative synthesis will be provided in text and table, to summarise the main results of the selected publications. A meta-analysis will be considered if there is sufficient homogeneity across outcomes. The quality of the included publications will be evaluated by the Grading of Recommendations Assessment, Development and Evaluation system from the Cochrane Handbook for Systematic Reviews of Interventions. ETHICS AND DISSEMINATION No ethical approval is needed, and the results of this review will be disseminated via peer-reviewed publications and conference presentations. TRIAL REGISTRATION NUMBER CRD42019128285.
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Affiliation(s)
- Hewei Wang
- Department of Rehabilitation, Huashan Hospital, Fudan University, Shanghai, China
| | - Ray Arceo
- Physical Therapy and Human Movement Sciences, Northwestern University, Chicago, Illinois, USA
| | - Shugeng Chen
- Department of Rehabilitation, Huashan Hospital, Fudan University, Shanghai, China
| | - Li Ding
- Department of Rehabilitation, Huashan Hospital, Fudan University, Shanghai, China
| | - Jie Jia
- Department of Rehabilitation, Huashan Hospital, Fudan University, Shanghai, China
| | - Jun Yao
- Physical Therapy and Human Movement Sciences, Northwestern University, Chicago, Illinois, USA
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Imbalanced Corticospinal and Reticulospinal Contributions to Spasticity in Humans with Spinal Cord Injury. J Neurosci 2019; 39:7872-7881. [PMID: 31413076 DOI: 10.1523/jneurosci.1106-19.2019] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 06/22/2019] [Accepted: 07/25/2019] [Indexed: 02/04/2023] Open
Abstract
Damage to the corticospinal and reticulospinal tract has been associated with spasticity in humans with upper motor neuron lesions. We hypothesized that these descending motor pathways distinctly contribute to the control of a spastic muscle in humans with incomplete spinal cord injury (SCI). To test this hypothesis, we examined motor-evoked potentials (MEPs) elicited by transcranial magnetic stimulation over the leg representation of the primary motor cortex, maximal voluntary contractions (MVCs), and the StartReact response (shortening in reaction time evoked by a startling stimulus) in the quadriceps femoris muscle in male and females with and without incomplete SCI. A total of 66.7% of the SCI participants showed symptoms of spasticity, whereas the other 33.3% showed no or low levels of spasticity. We found that participants with spasticity had smaller MEPs and MVCs and larger StartReact compared with participants with no or low spasticity and control subjects. These results were consistently present in spastic subjects but not in the other populations. Clinical scores of spasticity were negatively correlated with MEP-max and MVC values and positively correlated with shortening in reaction time. These findings provide evidence for lesser corticospinal and larger reticulospinal influences to spastic muscles in humans with SCI and suggest that these imbalanced contributions are important for motor recovery.SIGNIFICANCE STATEMENT Although spasticity is one of the most common symptoms manifested in humans with spinal cord injury (SCI) to date, its mechanisms of action remain poorly understood. We provide evidence, for the first time, of imbalanced contributions of the corticospinal and reticulospinal tract to control a spastic muscle in humans with chronic incomplete SCI. We found that participants with SCI with spasticity showed small corticospinal responses and maximal voluntary contractions and larger reticulospinal gain compared with participants with no or low spasticity and control subjects. These results were consistently present in spastic subjects but not in the other populations. We showed that imbalanced corticospinal and reticulospinal tract contributions are more pronounced in participants with chronic incomplete SCI with lesser recovery.
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Brainstem and spinal cord MRI identifies altered sensorimotor pathways post-stroke. Nat Commun 2019; 10:3524. [PMID: 31388003 PMCID: PMC6684621 DOI: 10.1038/s41467-019-11244-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 06/27/2019] [Indexed: 02/06/2023] Open
Abstract
Damage to the corticospinal tract is widely studied following unilateral subcortical stroke, whereas less is known about changes to other sensorimotor pathways. This may be due to the fact that many studies investigated morphological changes in the brain, where the majority of descending and ascending brain pathways are overlapping, and did not investigate the brainstem where they separate. Moreover, these pathways continue passing through separate regions in the spinal cord. Here, using a high-resolution structural MRI of both the brainstem and the cervical spinal cord, we were able to identify a number of microstructurally altered pathways, in addition to the corticospinal tract, post stroke. Moreover, decreases in ipsi-lesional corticospinal tract integrity and increases in contra-lesional medial reticulospinal tract integrity were correlated with motor impairment severity in individuals with stroke. There are few studies of structural changes in ascending and descending sensorimotor pathways after stroke, beyond the corticospinal tract, in the brain. Here the authors identify changes in white matter structure in brainstem and spinal cord following stroke, and show its relationship to motor impairment.
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Morecraft RJ, Ge J, Stilwell-Morecraft KS, Rotella DL, Pizzimenti MA, Darling WG. Terminal organization of the corticospinal projection from the lateral premotor cortex to the cervical enlargement (C5-T1) in rhesus monkey. J Comp Neurol 2019; 527:2761-2789. [PMID: 31032921 DOI: 10.1002/cne.24706] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 04/06/2019] [Accepted: 04/18/2019] [Indexed: 11/08/2022]
Abstract
High-resolution tract tracing and stereology were used to study the terminal organization of the corticospinal projection (CSP) from the ventral (v) and dorsal (d) regions of the lateral premotor cortex (LPMC) to spinal levels C5-T1. The LPMCv CSP originated from the postarcuate sulcus region, was bilateral, sparse, and primarily targeted the dorsolateral and ventromedial sectors of contralateral lamina VII. The convexity/lateral part of LPMCv did not project below C2. Thus, very little LPMCv corticospinal output reaches the cervical enlargement. In contrast, the LPMCd CSP was 5× more prominent in terminal density. Bilateral terminal labeling occurred in the medial sectors of lamina VII and adjacent lamina VIII, where propriospinal neurons with long-range bilateral axon projections reside. Notably, lamina VIII also harbors axial motoneurons. Contralateral labeling occurred in the lateral sectors of lamina VII and the dorsomedial quadrant of lamina IX, noted for harboring proximal upper limb flexor motoneurons. Segmentally, the CSP to contralateral laminae VII and IX preferentially innervated C5-C7, which supplies shoulder, elbow, and wrist musculature. In contrast, terminations in axial-related lamina VIII were distributed bilaterally throughout all cervical enlargement levels, including C8 and T1. These findings demonstrate the LPMCd CSP is structured to influence axial and proximal upper limb movements, supporting Kuypers conceptual view of the LPMCd CSP being a major component of the medial motor control system. Thus, distal upper extremity control influenced by LPMC, including grasping and manipulation, must occur through indirect neural network connections such as corticocortical, subcortical, or intrinsic spinal circuits.
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Affiliation(s)
- Robert J Morecraft
- Division of Basic Biomedical Sciences, Laboratory of Neurological Sciences, The University of South Dakota, Sanford School of Medicine, Vermillion, South Dakota
| | - Jizhi Ge
- Division of Basic Biomedical Sciences, Laboratory of Neurological Sciences, The University of South Dakota, Sanford School of Medicine, Vermillion, South Dakota
| | - Kim S Stilwell-Morecraft
- Division of Basic Biomedical Sciences, Laboratory of Neurological Sciences, The University of South Dakota, Sanford School of Medicine, Vermillion, South Dakota
| | - Diane L Rotella
- Department of Health and Human Physiology, Motor Control Laboratories, The University of Iowa, Iowa City, Iowa
| | - Marc A Pizzimenti
- Department of Health and Human Physiology, Motor Control Laboratories, The University of Iowa, Iowa City, Iowa.,Department of Anatomy and Cell Biology, Carver College of Medicine, The University of Iowa, Iowa City, Iowa
| | - Warren G Darling
- Department of Health and Human Physiology, Motor Control Laboratories, The University of Iowa, Iowa City, Iowa
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Chen YJ, Huang YZ, Chen CY, Chen CL, Chen HC, Wu CY, Lin KC, Chang TL. Intermittent theta burst stimulation enhances upper limb motor function in patients with chronic stroke: a pilot randomized controlled trial. BMC Neurol 2019; 19:69. [PMID: 31023258 PMCID: PMC6485156 DOI: 10.1186/s12883-019-1302-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 04/11/2019] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Intermittent theta burst stimulation (iTBS) is a form of repetitive transcranial stimulation that has been used to enhance upper limb (UL) motor recovery. However, only limited studies have examined its efficacy in patients with chronic stroke and therefore it remains controversial. METHODS This was a randomized controlled trial that enrolled patients from a rehabilitation department. Twenty-two patients with first-ever chronic and unilateral cerebral stroke, aged 30-70 years, were randomly assigned to the iTBS or control group. All patients received 1 session per day for 10 days of either iTBS or sham stimulation over the ipsilesional primary motor cortex in addition to conventional neurorehabilitation. Outcome measures were assessed before and immediately after the intervention period: Modified Ashworth Scale (MAS), Fugl-Meyer Assessment Upper Extremity (FMA-UE), Action Research Arm Test (ARAT), Box and Block test (BBT), and Motor Activity Log (MAL). Analysis of covariance was adopted to compare the treatment effects between groups. RESULTS The iTBS group had greater improvement in the MAS and FMA than the control group (η2 = 0.151-0.233; p < 0.05), as well as in the ARAT and BBT (η2 = 0.161-0.460; p < 0.05) with large effect size. Both groups showed an improvement in the BBT, and there were no significant between-group differences in MAL changes. CONCLUSIONS The iTBS induced greater gains in spasticity decrease and UL function improvement, especially in fine motor function, than sham TBS. This is a promising finding because patients with chronic stroke have a relatively low potential for fine motor function recovery. Overall, iTBS may be a beneficial adjunct therapy to neurorehabilitation for enhancing UL function. Further larger-scale study is warranted to confirm the findings and its long-term effect. TRIAL REGISTRATION This trial was registered under ClinicalTrials.gov ID No. NCT01947413 on September 20, 2013.
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Affiliation(s)
- Yu-Jen Chen
- Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, Linkou, 5, Fushing Street, Kuei-Shan District, Taoyuan City, 33305, Taiwan
| | - Ying-Zu Huang
- Neuroscience Research Center and Department of Neurology, Chang Gung Memorial Hospital, Linkou, Taiwan.,Institute of Cognitive Neuroscience, National Central University, Taoyuan, Taiwan.,Medical School, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Chung-Yao Chen
- Medical School, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Chia-Ling Chen
- Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, Linkou, 5, Fushing Street, Kuei-Shan District, Taoyuan City, 33305, Taiwan. .,Graduate Institute of Early Intervention, Chang Gung University, Taoyuan, Taiwan.
| | - Hsieh-Ching Chen
- Department of Industrial and Management, National Taipei University of Technology, Taipei, Taiwan
| | - Ching-Yi Wu
- Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, Linkou, 5, Fushing Street, Kuei-Shan District, Taoyuan City, 33305, Taiwan.,Department of Occupational Therapy, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Keh-Chung Lin
- School of Occupational Therapy, College of Medicine, National Taiwan University, Taipei, Taiwan.,Division of Occupational Therapy, Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, Taipei, Taiwan
| | - Tzu-Ling Chang
- Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, Linkou, 5, Fushing Street, Kuei-Shan District, Taoyuan City, 33305, Taiwan
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Choudhury S, Shobhana A, Singh R, Sen D, Anand SS, Shubham S, Baker MR, Kumar H, Baker SN. The Relationship Between Enhanced Reticulospinal Outflow and Upper Limb Function in Chronic Stroke Patients. Neurorehabil Neural Repair 2019; 33:375-383. [DOI: 10.1177/1545968319836233] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Background. Recent evidence from both monkey and human studies suggests that the reticulospinal tract may contribute to recovery of arm and hand function after stroke. In this study, we evaluated a marker of reticulospinal output in stroke survivors with varying degrees of motor recovery. Methods. We recruited 95 consecutive stroke patients presenting 6 months to 12 years after their index stroke, and 19 heathy control subjects. Subjects were asked to respond to a light flash with a rapid wrist flexion; at random, the flash was paired with either a quiet or loud (startling) sound. The mean difference in electromyogram response time after flash with quiet sound compared with flash with loud sound measured the StartReact effect. Upper limb function was assessed by the Action Research Arm Test (ARAT), spasticity was graded using the Modified Ashworth Scale (MAS) and active wrist angular movement using an electrogoniometer. Results. StartReact was significantly larger in stroke patients than healthy participants (78.4 vs 45.0 ms, P < .005). StartReact showed a significant negative correlation with the ARAT score and degree of active wrist movement. The StartReact effect was significantly larger in patients with higher spasticity scores. Conclusion. We speculate that in some patients with severe damage to their corticospinal tract, recovery led to strengthening of reticulospinal connections and an enhanced StartReact effect, but this did not occur for patients with milder impairment who could use surviving corticospinal connections to mediate recovery.
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Affiliation(s)
| | | | - Ravi Singh
- Institute of Neurosciences, Kolkata, India
| | | | | | | | - Mark R. Baker
- Department of Clinical Neurophysiology and Department of Neurology, Royal Victoria Infirmary, Newcastle upon Tyne, UK
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK
| | | | - Stuart N. Baker
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK
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Foysal KMR, Baker SN. A hierarchy of corticospinal plasticity in human hand and forearm muscles. J Physiol 2019; 597:2729-2739. [PMID: 30839110 PMCID: PMC6567854 DOI: 10.1113/jp277462] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Accepted: 02/27/2019] [Indexed: 02/05/2023] Open
Abstract
Key points Pairing stimulation of a finger flexor or extensor muscle at the motor point with transcranial magnetic stimulation (TMS) of the motor cortex generated plastic changes in motor output. Increases in output were greater in intrinsic hand muscles than in the finger flexor. No changes occurred in the finger extensor. This gradient was seen irrespective of which muscle was stimulated paired with transcranial magnetic stimulation. Intermittent theta‐burst stimulation also produced increases in output, although these were similar across muscles. We suggest that intrinsic hand and flexor muscles have a higher potential to show plasticity than extensors, although only when plasticity is induced by sensory input. This may relate to differences seen in recovery of function in these muscles after injury, such as post‐stroke.
Abstract The ability of the motor system to show plastic change underlies skill learning and also permits recovery after injury. One puzzling observation is that, after stroke, upper limb flexor muscles show good recovery but extensors remain weak, with this being a major contributor to residual disability. We hypothesized that there might be differences in potential for plasticity across hand and forearm muscles. In the present study, we investigated this using two protocols based on transcranial magnetic brain stimulation (TMS) in healthy human subjects. Baseline TMS responses were recorded from two intrinsic hand muscles: flexor digitorum superficialis (FDS) and extensor digitorum communis (EDC). In the first study, paired associative stimulation (PAS) was delivered by pairing motor point stimulation of FDS or EDC with TMS. Responses were then remeasured. Increases were greatest in the hand muscles, smaller in FDS and non‐significant in EDC, irrespective of whether stimulation of FDS or EDC was used. In the second study, intermittent theta‐burst rapid rate TMS was applied instead of PAS. In this case, all muscles showed similar increases in TMS responses. We conclude that the potential to show plastic changes in motor cortical output has the gradient: hand muscles > flexors > extensors. However, this was only seen in a protocol that requires integration of sensory input (PAS) and not when plasticity was induced purely by cortical stimulation (rapid rate TMS). This observation may relate to why functional recovery tends to favour flexor and hand muscles over extensors. Pairing stimulation of a finger flexor or extensor muscle at the motor point with transcranial magnetic stimulation (TMS) of the motor cortex generated plastic changes in motor output. Increases in output were greater in intrinsic hand muscles than in the finger flexor. No changes occurred in the finger extensor. This gradient was seen irrespective of which muscle was stimulated paired with transcranial magnetic stimulation. Intermittent theta‐burst stimulation also produced increases in output, although these were similar across muscles. We suggest that intrinsic hand and flexor muscles have a higher potential to show plasticity than extensors, although only when plasticity is induced by sensory input. This may relate to differences seen in recovery of function in these muscles after injury, such as post‐stroke.
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Affiliation(s)
- K M Riashad Foysal
- Institute of Neurosciences, Newcastle University, Newcastle upon Tyne, UK
| | - Stuart N Baker
- Institute of Neurosciences, Newcastle University, Newcastle upon Tyne, UK
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The unsolved role of heightened connectivity from the unaffected hemisphere to paretic arm muscles in chronic stroke. Clin Neurophysiol 2019; 130:781-788. [PMID: 30925310 DOI: 10.1016/j.clinph.2019.02.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 02/06/2019] [Accepted: 02/27/2019] [Indexed: 01/25/2023]
Abstract
OBJECTIVE Ipsilateral connectivity from the non-stroke hemisphere to paretic arm muscles appears to play little role in functional recovery, which instead depends on contralateral connectivity from the stroke hemisphere. Yet the incidence of ipsilateral projections in stroke survivors is often reported to be higher than normal. We tested this directly using a sensitive measure of connectivity to proximal arm muscles. METHOD TMS of the stroke and non-stroke motor cortex evoked responses in pre-activated triceps and deltoid muscles of 17 stroke survivors attending reaching training. Connectivity was defined as a clear MEP or a short-latency silent period in ongoing EMG in ≥ 50% of stimulations. We measured reaching accuracy at baseline, improvement after training and upper limb Fugl-Meyer (F-M) score. RESULTS Incidence of ipsilateral connections to triceps (47%) and deltoid (58%) was high, but unrelated to baseline reaching accuracy and F-M scores. Instead, these were related to contralateral connectivity from the stroke hemisphere. Absolute but not proportional improvement after training was greater in patients with ipsilateral responses. CONCLUSIONS Despite enhanced ipsilateral connectivity, arm function and learning was related most strongly to contralateral pathway integrity from the stroke hemisphere. SIGNIFICANCE Further work is needed to decipher the role of ipsilateral connections.
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McPherson LM, Dewald JPA. Differences between flexion and extension synergy-driven coupling at the elbow, wrist, and fingers of individuals with chronic hemiparetic stroke. Clin Neurophysiol 2019; 130:454-468. [PMID: 30771722 DOI: 10.1016/j.clinph.2019.01.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2016] [Revised: 01/04/2019] [Accepted: 01/09/2019] [Indexed: 12/21/2022]
Abstract
OBJECTIVE The flexion and extension synergies were quantified at the paretic elbow, forearm, wrist, and finger joints within the same group of participants for the first time. Differences in synergy expression at each of the four joints were examined, as were the ways these differences varied across the joints. METHODS Twelve post-stroke individuals with chronic moderate-to-severe hemiparesis and six age-matched controls participated. Participants generated isometric shoulder abduction (SABD) and shoulder adduction (SADD) at four submaximal levels to progressively elicit the flexion and extension synergies, respectively. Isometric joint torques and EMG were recorded from shoulder, elbow, forearm (radio-ulnar), wrist, and finger joints and muscles. RESULTS SABD elicited strong wrist and finger flexion torque that increased with shoulder torque level. SADD produced primarily wrist and finger flexion torque, but magnitudes at the wrist were less than during SABD. Findings contrasted with those at the elbow and forearm, where torques and EMG generated due to SABD and SADD were opposite in direction. CONCLUSIONS Flexion and extension synergy expression are more similar at the hand than at the shoulder and elbow. Specific bulbospinal pathways that may underlie flexion and extension synergy expression are discussed. SIGNIFICANCE Whole-limb behavior must be considered when examining paretic hand function in moderately-to-severely impaired individuals.
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Affiliation(s)
- Laura Miller McPherson
- Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL, USA; Department of Physical Therapy, Nicole Wertheim College of Nursing and Health Sciences, Florida International University, Miami, FL, USA; Department of Biomedical Engineering, College of Engineering and Computing, Florida International University, Miami, FL, USA
| | - Julius P A Dewald
- Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL, USA; Department of Physical Medicine and Rehabilitation, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
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StartReact during gait initiation reveals differential control of muscle activation and inhibition in patients with corticospinal degeneration. J Neurol 2018; 265:2531-2539. [PMID: 30155740 PMCID: PMC6182706 DOI: 10.1007/s00415-018-9027-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 08/17/2018] [Accepted: 08/20/2018] [Indexed: 12/25/2022]
Abstract
Corticospinal lesions cause impairments in voluntary motor control. Recent findings suggest that some degree of voluntary control may be taken over by a compensatory pathway involving the reticulospinal tract. In humans, evidence for this notion mainly comes from StartReact studies. StartReact is the acceleration of reaction times by a startling acoustic stimulus (SAS) simultaneously presented with the imperative stimulus. As previous StartReact studies mainly focused on isolated single-joint movements, the question remains whether the reticulospinal tract can also be utilized for controlling whole-body movements. To investigate reticulospinal control, we applied the StartReact paradigm during gait initiation in 12 healthy controls and 12 patients with ‘pure’ hereditary spastic paraplegia (HSP; i.e., retrograde axonal degeneration of corticospinal tract). Participants performed three consecutive steps in response to an imperative visual stimulus. In 25% of 16 trials a SAS was applied. We determined reaction times of muscle (de)activation, anticipatory postural adjustments (APA) and steps. Without SAS, we observed an overall delay in HSP patients compared to controls. Administration of the SAS accelerated tibialis anterior and rectus femoris onsets in both groups, but more so in HSP patients, resulting in (near-)normal latencies. Soleus offsets were accelerated in controls, but not in HSP patients. The SAS also accelerated APA and step reaction times in both groups, yet these did not normalize in the HSP patients. The reticulospinal tract is able to play a compensatory role in voluntary control of whole-body movements, but seems to lack the capacity to inhibit task-inappropriate muscle activity in patients with corticospinal lesions.
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Hand Motor Recovery Following Extensive Frontoparietal Cortical Injury Is Accompanied by Upregulated Corticoreticular Projections in Monkey. J Neurosci 2018; 38:6323-6339. [PMID: 29899028 DOI: 10.1523/jneurosci.0403-18.2018] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 05/21/2018] [Accepted: 05/30/2018] [Indexed: 12/25/2022] Open
Abstract
We tested the hypothesis that arm/hand motor recovery after injury of the lateral sensorimotor cortex is associated with upregulation of the corticoreticular projection (CRP) from the supplementary motor cortex (M2) to the gigantocellular reticular nucleus of the medulla (Gi). Three groups of rhesus monkeys of both genders were studied: five controls, four cases with lesions of the arm/hand area of the primary motor cortex (M1) and the lateral premotor cortex (LPMC; F2 lesion group), and five cases with lesions of the arm/hand area of M1, LPMC, S1, and anterior parietal cortex (F2P2 lesion group). CRP strength was assessed using high-resolution anterograde tracers injected into the arm/hand area of M2 and stereology to estimate of the number of synaptic boutons in the Gi. M2 projected bilaterally to the Gi, primarily targeting the medial Gi subsector and, to a lesser extent, lateral, dorsal, and ventral subsectors. Total CRP bouton numbers were similar in controls and F2 lesion cases but F2P2 lesion cases had twice as many boutons as the other two groups (p = 0.0002). Recovery of reaching and fine hand/digit function was strongly correlated with estimated numbers of CRP boutons in the F2P2 lesion cases. Because we previously showed that F2P2 lesion cases experience decreased strength of the M2 corticospinal projection (CSP), whereas F2 lesion monkeys experienced increased strength of the M2 CSP, these results suggest one mechanism underlying arm/hand motor recovery after F2P2 injury is upregulation of the M2 CRP. This M2-CRP response may influence an important reticulospinal tract contribution to upper-limb motor recovery following frontoparietal injury.SIGNIFICANCE STATEMENT We previously showed that after brain injury affecting the lateral motor cortex controlling arm/hand motor function, recovery is variable and closely associated with increased strength of corticospinal projection (CSP) from an uninjured medial cortical motor area. Hand motor recovery also varies after brain injury affecting the lateral sensorimotor cortex, but medial motor cortex CSP strength decreases and cannot account for recovery. Here we observed that motor recovery following sensorimotor cortex injury is closely associated with increased strength of the descending projection from an uninjured medial cortical motor area to a brainstem reticular nucleus involved in control of arm/hand function, suggesting an enhanced corticoreticular projection may compensate for injury to the sensorimotor cortex to enable recovery of arm/hand motor function.
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