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Massé-Alarie H, Shraim M, Hodges PW. Sensorimotor Integration in Chronic Low Back Pain. Neuroscience 2024; 552:29-38. [PMID: 38878816 DOI: 10.1016/j.neuroscience.2024.06.008] [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: 02/07/2024] [Revised: 05/02/2024] [Accepted: 06/10/2024] [Indexed: 06/24/2024]
Abstract
OBJECTIVE Chronic low back pain (CLBP) impacts on spine movement. Altered sensorimotor integration can be involved. Afferents from the lumbo-pelvic area might be processed differently in CLBP and impact on descending motor control. This study aimed to determine whether afferents influence the corticomotor control of paravertebral muscles in CLBP. Fourteen individuals with CLBP (11 females) and 13 pain-free controls (8 females) were tested with transcranial magnetic stimulation (TMS) to measure the motor-evoked potential [MEP] amplitude of paravertebral muscles. Noxious and non-noxious electrical stimulation, and magnetic stimulation in the lumbo-sacral area were used as afferent stimuli and triggered 20 to 200 ms prior to TMS. EMG modulation elicited by afferent stimulation alone was measured to control net motoneuron excitability. MEP/EMG ratio was used as a measure of corticospinal excitability with control of net motoneuron excitability. MEP/EMG ratio was larger at 60, 80 and 100-ms intervals in CLBP compared to controls, and afferent stimulations alone reduced EMG amplitude greater in CLBP than controls at 100 ms. Our results suggest alteration in sensorimotor integration in CLBP highlighted by a greater facilitation of the descending corticospinal input to paravertebral muscles. Our results can help to optimise interventions by better targeting mechanisms.
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Affiliation(s)
- Hugo Massé-Alarie
- The University of Queensland, NHMRC Centre of Clinical Research Excellence in Spinal Pain, Injury & Health, School of Health & Rehabilitation Sciences, Brisbane, QLD, Australia; Centre Interdisciplinaire de Recherche en Réadaptation et Intégration Sociale (CIRRIS), Université Laval, Québec, Canada.
| | - Muath Shraim
- The University of Queensland, NHMRC Centre of Clinical Research Excellence in Spinal Pain, Injury & Health, School of Health & Rehabilitation Sciences, Brisbane, QLD, Australia
| | - Paul W Hodges
- The University of Queensland, NHMRC Centre of Clinical Research Excellence in Spinal Pain, Injury & Health, School of Health & Rehabilitation Sciences, Brisbane, QLD, Australia
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2
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Chiou S, Unwin C, Lilley A. Age-related changes in reticulospinal contributions to anticipatory postural adjustments between back extensors and abdominal muscles. Exp Physiol 2024; 109:1177-1187. [PMID: 38745546 PMCID: PMC11215469 DOI: 10.1113/ep091698] [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: 12/17/2023] [Accepted: 04/12/2024] [Indexed: 05/16/2024]
Abstract
Anticipatory postural adjustments (APAs) give feedforward postural control of the trunk, but they are delayed with ageing, affecting balance and mobility in older individuals. The reticulospinal tract contributes to postural control of the trunk; however, the extent to which age-related changes affect the reticulospinal contributions to APAs of the trunk remains unknown in humans. Here, we tested the hypothesis that a startling acoustic sound, which activates the reticulospinal tract, improves delayed APAs in older individuals. Twenty-two old (75 ± 6 years) and 20 healthy young adults (21 ± 4 years) performed a self-initiated fast bilateral shoulder flexion or shoulder extension task in response to visual, visual and auditory (80 dB), or visual and startling (115 dB) cues. Electromyography (EMG) was recorded from bilateral anterior deltoid (AD) and erector spinae (ES) during shoulder flexion and from bilateral posterior deltoid (PD) and rectus abdominis (RA) during shoulder extension. EMG onset of all muscles shortened during the startling cue in both age groups, suggesting a non-specific modulation of the reticulospinal tract on prime movers (AD or PD) and non-prime movers (ES or RA). Interestingly, APAs of the ES were accelerated in older participants to a similar degree as in younger participants during the startling cue. Conversely, APAs of the RA were not influenced by the startling cue in older participants. Our results suggest differential effects of ageing on functional contributions of the reticulospinal tract to APAs between back extensors and abdominal muscles.
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Affiliation(s)
- Shin‐Yi Chiou
- School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental SciencesUniversity of BirminghamBirminghamUK
| | - Catherine Unwin
- School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental SciencesUniversity of BirminghamBirminghamUK
- Sandwell and West Birmingham NHS TrustTreatment centre, City HospitalBirminghamUK
| | - Alice Lilley
- School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental SciencesUniversity of BirminghamBirminghamUK
- Musculoskeletal Outpatients DepartmentQueen's Hospital BurtonBurton‐On‐TrentStaffordshireUK
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3
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Desmons M, Cherif A, Rohel A, de Oliveira FCL, Mercier C, Massé-Alarie H. Corticomotor Control of Lumbar Erector Spinae in Postural and Voluntary Tasks: The Influence of Transcranial Magnetic Stimulation Current Direction. eNeuro 2024; 11:ENEURO.0454-22.2023. [PMID: 38167617 PMCID: PMC10883751 DOI: 10.1523/eneuro.0454-22.2023] [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: 10/28/2022] [Revised: 11/30/2023] [Accepted: 12/16/2023] [Indexed: 01/05/2024] Open
Abstract
Lumbar erector spinae (LES) contribute to spine postural and voluntary control. Transcranial magnetic stimulation (TMS) preferentially depolarizes different neural circuits depending on the direction of electrical currents evoked in the brain. Posteroanterior current (PA-TMS) and anteroposterior (AP-TMS) current would, respectively, depolarize neurons in the primary motor cortex (M1) and the premotor cortex. These regions may contribute differently to LES control. This study examined whether responses evoked by PA- and AP-TMS are different during the preparation and execution of LES voluntary and postural tasks. Participants performed a reaction time task. A Warning signal indicated to prepare to flex shoulders (postural; n = 15) or to tilt the pelvis (voluntary; n = 13) at the Go signal. Single- and paired-pulse TMS (short-interval intracortical inhibition-SICI) were applied using PA- and AP-TMS before the Warning signal (baseline), between the Warning and Go signals (preparation), or 30 ms before the LES onset (execution). Changes from baseline during preparation and execution were calculated in AP/PA-TMS. In the postural task, MEP amplitude was higher during the execution than that during preparation independently of the current direction (p = 0.0002). In the voluntary task, AP-MEP amplitude was higher during execution than that during preparation (p = 0.016). More PA inhibition (SICI) was observed in execution than that in preparation (p = 0.028). Different neural circuits are preferentially involved in the two motor tasks assessed, as suggested by different patterns of change in execution of the voluntary task (AP-TMS, increase; PA-TMS, no change). Considering that PA-TMS preferentially depolarize neurons in M1, it questions their importance in LES voluntary control.
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Affiliation(s)
- Mikaël Desmons
- Center for Interdisciplinary Research in Rehabilitation and Social Integration (Cirris), CIUSSS de la Capitale-Nationale, Quebec City, Quebec G1M 2S8, Canada
- Rehabilitation Department, University Laval, Quebec City, Quebec G1V 0A6, Canada, G1V 0A6
| | - Amira Cherif
- Center for Interdisciplinary Research in Rehabilitation and Social Integration (Cirris), CIUSSS de la Capitale-Nationale, Quebec City, Quebec G1M 2S8, Canada
- Rehabilitation Department, University Laval, Quebec City, Quebec G1V 0A6, Canada, G1V 0A6
| | - Antoine Rohel
- Center for Interdisciplinary Research in Rehabilitation and Social Integration (Cirris), CIUSSS de la Capitale-Nationale, Quebec City, Quebec G1M 2S8, Canada
- Rehabilitation Department, University Laval, Quebec City, Quebec G1V 0A6, Canada, G1V 0A6
| | - Fábio Carlos Lucas de Oliveira
- Center for Interdisciplinary Research in Rehabilitation and Social Integration (Cirris), CIUSSS de la Capitale-Nationale, Quebec City, Quebec G1M 2S8, Canada
- Rehabilitation Department, University Laval, Quebec City, Quebec G1V 0A6, Canada, G1V 0A6
| | - Catherine Mercier
- Center for Interdisciplinary Research in Rehabilitation and Social Integration (Cirris), CIUSSS de la Capitale-Nationale, Quebec City, Quebec G1M 2S8, Canada
- Rehabilitation Department, University Laval, Quebec City, Quebec G1V 0A6, Canada, G1V 0A6
| | - Hugo Massé-Alarie
- Center for Interdisciplinary Research in Rehabilitation and Social Integration (Cirris), CIUSSS de la Capitale-Nationale, Quebec City, Quebec G1M 2S8, Canada
- Rehabilitation Department, University Laval, Quebec City, Quebec G1V 0A6, Canada, G1V 0A6
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Saraiepour S, Kahrizi S, Ghabaee M, Bazrgari B. Mapping the Cortical Representation of Paraspinal Muscles Using Transcranial Magnetic Stimulation Optimized in People With Chronic Back Pain. Basic Clin Neurosci 2023; 14:827-841. [PMID: 39070195 PMCID: PMC11273208 DOI: 10.32598/bcn.2023.4419.1] [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: 07/15/2022] [Revised: 12/24/2022] [Accepted: 01/15/2023] [Indexed: 07/30/2024] Open
Abstract
Introduction Chronic low back pain (CLBP) is a global burden with an unknown etiology. Reorganization of the cortical representation of paraspinal muscles in the primary motor cortex (M1) may be related to the pathology. Single-pulse transcranial magnetic stimulation (TMS), commonly used to map the functional organization of M1, is not potent enough to stimulate the cortical maps of paraspinal muscles in M1 in CLBP patients with reduced corticospinal excitability (CSE) with intensities even as high as maximum stimulator output (100% MSO). This makes TMS mapping impractical for these patients. The aim of this study was to increase the practicality of TMS mapping for people with CLBP. Methods This study included eight men and ten women who had CLBP for over three months. A biphasic paired-pulse TMS paradigm, conjunct anticipatory postural adjustment (APA), and maximal voluntary activation of paraspinal muscles (MVC) were used to facilitate TMS mapping. Results TMS mapping was possible in all CLBP participants, with TMS intensities <50% of the MSO. Reorganization in terms of an anterior and lateral shift of the center of gravity (COG) of the cortical maps of paraspinal muscles was observed in all participants with CLBP, and a reduced number of discrete peaks was found in 33%. Conclusion The facilitation of the CSE to paraspinal muscles makes TMS mapping more practical and tolerable in people with CLBP, lowering the risk of seizure and discomfort associated with high-intensity TMS pulses. Highlights Conventional transcranial magnetic stimulation (TMS) brain mapping is not optimal for patients with Chronic low back pain (CLBP).Paired-pulse TMS dramatically lessens the energy needed for brain mapping.Maximal voluntary contraction of back muscles facilitates TMS mapping.Anticipatory postural activity of back muscles enhances the efficacy of TMS mapping. Plain Language Summary Chronic low back pain (CLBP) is a social, emotional, and economic burden and the leading cause of disability worldwide. Yet the etiology of the CLBP is unknown. The persistence of aberrant or antalgic movement patterns observed in people with CLBP has been suggested as a possible cause of pain chronification by inducing continuous damage to sensitive structures of the lumbar spine. It is well known that the brain is in charge of the production and planning of movements, so it is likely that abnormal movement patterns also stem from the abnormalities in the brain. However, until recently, human knowledge about the structure and function of the brain has been very limited. The invention of noninvasive and painless brain imaging and stimulating techniques such as transcranial magnetic stimulation (TMS) during the last decades has augmented our knowledge about the structure and function of the brain. Modification in terms of shift, shrinkage, or expansion of areas of the brain devoted to movement control or sensation of the back muscles has been documented in CLBP via these techniques, which are argued to relate to pain chronification but need further clarification. Yet monitoring the course of CLBP via TMS, despite its many potentials, is challenging. This could be due to the reduced cortical drive to back muscles in CLBP patients and the small area devoted to control of back muscles in the brain in general that increases the brain threshold to TMS in people with CLBP. The aim of this study was to tailor an approach to make TMS more applicable for CLBP patients by reducing the threshold to TMS. This could be achieved by engaging back muscles in anticipatory postural activity in combination with maximal voluntary activation of these muscles, along with TMS paradigms that induce intracortical facilitation.
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Affiliation(s)
- Solaleh Saraiepour
- Department of Physiotherapy, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Sedigheh Kahrizi
- Department of Physiotherapy, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Mojdeh Ghabaee
- Department of Neurology, Faculty of Medical Sciences, Iranian Center of Neurological Research, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Babak Bazrgari
- Department of Biomedical Engineering, University of Kentucky, Lexington, United States
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5
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Desmons M, Theberge M, Mercier C, Massé-Alarie H. Contribution of neural circuits tested by transcranial magnetic stimulation in corticomotor control of low back muscle: a systematic review. Front Neurosci 2023; 17:1180816. [PMID: 37304019 PMCID: PMC10247989 DOI: 10.3389/fnins.2023.1180816] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 05/10/2023] [Indexed: 06/13/2023] Open
Abstract
Introduction Transcranial magnetic stimulation (TMS) is widely used to investigate central nervous system mechanisms underlying motor control. Despite thousands of TMS studies on neurophysiological underpinnings of corticomotor control, a large majority of studies have focused on distal muscles, and little is known about axial muscles (e.g., low back muscles). Yet, differences between corticomotor control of low back and distal muscles (e.g., gross vs. fine motor control) suggest differences in the neural circuits involved. This systematic review of the literature aims at detailing the organisation and neural circuitry underlying corticomotor control of low back muscles tested with TMS in healthy humans. Methods The literature search was performed in four databases (CINAHL, Embase, Medline (Ovid) and Web of science) up to May 2022. Included studies had to use TMS in combination with EMG recording of paraspinal muscles (between T12 and L5) in healthy participants. Weighted average was used to synthesise quantitative study results. Results Forty-four articles met the selection criteria. TMS studies of low back muscles provided consistent evidence of contralateral and ipsilateral motor evoked potentials (with longer ipsilateral latencies) as well as of short intracortical inhibition/facilitation. However, few or no studies using other paired pulse protocols were found (e.g., long intracortical inhibition, interhemispheric inhibition). In addition, no study explored the interaction between different cortical areas using dual TMS coil protocol (e.g., between primary motor cortex and supplementary motor area). Discussion Corticomotor control of low back muscles are distinct from hand muscles. Our main findings suggest: (i) bilateral projections from each single primary motor cortex, for which contralateral and ipsilateral tracts are probably of different nature (contra: monosynaptic; ipsi: oligo/polysynaptic) and (ii) the presence of intracortical inhibitory and excitatory circuits in M1 influencing the excitability of the contralateral corticospinal cells projecting to low back muscles. Understanding of these mechanisms are important for improving the understanding of neuromuscular function of low back muscles and to improve the management of clinical populations (e.g., low back pain, stroke).
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Affiliation(s)
- Mikaël Desmons
- Center for Interdisciplinary Research in Rehabilitation and Social Integration (Cirris), CIUSSS de la Capitale-Nationale, Quebec, QC, Canada
- Rehabilitation Department, Université Laval, Quebec, QC, Canada
| | - Michael Theberge
- Center for Interdisciplinary Research in Rehabilitation and Social Integration (Cirris), CIUSSS de la Capitale-Nationale, Quebec, QC, Canada
| | - Catherine Mercier
- Center for Interdisciplinary Research in Rehabilitation and Social Integration (Cirris), CIUSSS de la Capitale-Nationale, Quebec, QC, Canada
- Rehabilitation Department, Université Laval, Quebec, QC, Canada
| | - Hugo Massé-Alarie
- Center for Interdisciplinary Research in Rehabilitation and Social Integration (Cirris), CIUSSS de la Capitale-Nationale, Quebec, QC, Canada
- Rehabilitation Department, Université Laval, Quebec, QC, Canada
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6
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Ma W, Nemdharry S, Elgueta Cancino E, Chiou SY. Influence of coil orientation on corticospinal excitability of trunk muscles during postural and volitional tasks in healthy adults. Front Hum Neurosci 2023; 17:1108169. [PMID: 36816500 PMCID: PMC9929149 DOI: 10.3389/fnhum.2023.1108169] [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: 11/25/2022] [Accepted: 01/16/2023] [Indexed: 02/04/2023] Open
Abstract
Introduction Trunk muscles play a role in maintaining postural stability and performing goal-directed voluntary movements in activities of daily living. Evidence has shown that the primary motor cortex (M1) is involved in modulation of postural control and voluntary movements of the trunk. However, it remains unknown whether the neural circuits within the M1 were recruited to the same extent between a postural task and a goal-directed voluntary task. Methods To address this, we examined latencies and amplitudes of motor evoked potentials (MEPs) of the erector spinae (ES) with transcranial magnetic stimulation (TMS) figure-of-eight coil oriented to induce latero-medial (LM), posterior-anterior (PA), and anterior-posterior (AP) currents in the M1 in twenty healthy participants during a dynamic shoulder flexion (DSF) task, a postural task requiring anticipatory postural adjustments (APAs), and during a static trunk extension (STE) task, a voluntary task without involvement of APAs. Results We found that differences in the AP-LM latency of ES MEP were longer compared with the PA-LM latency in both tasks. Corticospinal excitability was overall greater during the DSF task than during the STE task irrespective of the coil orientation. Discussion Our findings suggest that while the same neural circuits in the M1 were recruited to modulate both postural and voluntary control of the trunk, the contribution was greater to the postural task than the voluntary task, possibly due to the requirement of APAs in the task.
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Affiliation(s)
- Wesley Ma
- School of Sport, Exercise and Rehabilitation Science, University of Birmingham, Birmingham, United Kingdom
| | - Sheanil Nemdharry
- School of Sport, Exercise and Rehabilitation Science, University of Birmingham, Birmingham, United Kingdom
| | - Edith Elgueta Cancino
- School of Sport, Exercise and Rehabilitation Science, University of Birmingham, Birmingham, United Kingdom,Exercise and Rehabilitation Sciences Institute, School of Physical Therapy, Faculty of Rehabilitation Science, Universidad Andrés Bello, Santiago, Chile
| | - Shin-Yi Chiou
- School of Sport, Exercise and Rehabilitation Science, University of Birmingham, Birmingham, United Kingdom,*Correspondence: Shin-Yi Chiou ✉
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External and internal focus of attention differentially modulate corticospinal excitability in anticipatory postural adjustments. Sci Rep 2022; 12:22385. [PMID: 36572719 PMCID: PMC9792519 DOI: 10.1038/s41598-022-26987-1] [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: 07/05/2022] [Accepted: 12/22/2022] [Indexed: 12/27/2022] Open
Abstract
Whether attentional focus modulates the corticospinal excitability of the lower limb muscles in anticipatory postural adjustments (APAs) when performing a ballistic movement of the upper limb remains unclear. The present study used transcranial magnetic stimulation (TMS) to examine the corticospinal excitability of the lower limb muscles along with the kinematic profiles during dart throwing with different attentional foci, external focus (EF) and internal focus (IF). In 13 healthy participants, TMS was applied immediately before electromyographic onset of the tibialis anterior (TA) muscle, and the motor evoked potential (MEP) was recorded in the TA and soleus (SOL) muscles. The performance accuracy was significantly higher in the EF condition than in the IF condition. In both EF and IF conditions, MEP amplitude in the TA muscle, but not the SOL muscle, was significantly higher immediately before TA muscle onset (- 100, - 50, and 0 ms) compared to the control. In particular, the MEP increment in the TA muscle before TA muscle onset (- 50 and 0 ms) was significantly larger in the EF condition than in the IF condition. Our findings provide the first evidence for the modulation of corticospinal excitability in APA by changing attentional focus.
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Reliability of high-density surface electromyography for assessing characteristics of the thoracic erector spinae during static and dynamic tasks. J Electromyogr Kinesiol 2022; 67:102703. [PMID: 36096034 DOI: 10.1016/j.jelekin.2022.102703] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 08/03/2022] [Accepted: 08/31/2022] [Indexed: 12/14/2022] Open
Abstract
PURPOSE To establish intra- and inter-session reliability of high-density surface electromyography (HDEMG)-derived parameters from the thoracic erector spinae (ES) during static and dynamic goal-directed voluntary movements of the trunk, and during functional reaching tasks. METHODS Twenty participants performed: 1) static trunk extension, 2) dynamic trunk forward and lateral flexion, and 3) multidirectional functional reaching tasks on two occasions separated by 7.5 ± 1.2 days. Muscle activity was recorded bilaterally from the thoracic ES. Root mean square (RMS), coordinates of the barycentre, mean frequency (MNF), and entropy were derived from the HDEMG signals. Reliability was determined with intraclass correlation coefficient (ICC), coefficient of variation, and standard error of measurement. RESULTS Good-to-excellent intra-session reliability was found for all parameters and tasks (ICC: 0.79-0.99), whereas inter-session reliability varied across tasks. Static tasks demonstrated higher reliability in most parameters compared to functional and dynamic tasks. Absolute RMS and MNF showed the highest overall reliability across tasks (ICC: 0.66-0.98), while reliability of the barycentre was influenced by the direction of the movements. CONCLUSION RMS and MNF derived from HDEMG show consistent inter-session reliability in goal-directed voluntary movements of the trunk and reaching tasks, whereas the measures of the barycentre and entropy demonstrate task-dependent reliability.
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Santamaria V, Ai X, Agrawal SK. A motor learning-based postural intervention with a robotic trunk support trainer to improve functional sitting in spinal cord injury: case report. Spinal Cord Ser Cases 2022; 8:88. [PMID: 36433944 PMCID: PMC9700847 DOI: 10.1038/s41394-022-00554-2] [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: 03/26/2022] [Accepted: 11/08/2022] [Indexed: 11/26/2022] Open
Abstract
STUDY DESIGN Single-subject-research-design. OBJECTIVES To improve seated postural control in a participant with spinal cord injury (SCI) with a robotic Trunk-Support-Trainer (TruST). SETTING Laboratory. METHODS TruST delivered "assist-as-needed" forces on the participant's torso during a motor learning-and-control-based intervention (TruST-intervention). TruST-assistive forces were progressed and matched to the participant's postural trunk control gains across six intervention sessions. The T-shirt test was used to capture functional improvements while dressing the upper body. Kinematics were used to compute upper body excursions (cm) and velocity (cm2), and sitting workspace area (cm2). Functional trunk dynamometry was used to examine muscle force (Kg). Surface electromyography (sEMG) was applied to measure trunk muscle activity. The Borg Rating of Perceived Exertion (RPE) was used to monitor physical exertion during TruST-intervention. A two-standard-deviation bandwidth method was adopted for data interpretation. RESULTS After TruST-intervention, the participant halved the time needed to don and doff a T-shirt, increased muscle force of trunk muscles (mean = 3 kg), acquired a steadier postural sitting control without vision (mean excursion baseline: 76.0 ± 2 SD = 5.25 cm and post-intervention: 44.1 cm; and mean velocity baseline: 3.0 ± 2 SD = 0.2 cm/s and post-intervention: 1.8 cm/s), and expanded his sitting workspace area (mean baseline: 36.7 ± 2 SD = 36.6 cm2 and post-intervention: 419.2 cm2). The participant increased his tolerance to counteract greater TruST-force perturbations in lateral and posterior directions. Furthermore, abdominal muscle activity substantially augmented after completion of TruST-intervention across all perturbation directions. CONCLUSIONS Our data indicate a potential effectiveness of TruST-intervention to promote functional sitting in SCI.
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Affiliation(s)
- V Santamaria
- Department of Physical Therapy, New York Medical College, New York, NY, USA
| | - X Ai
- Department of Mechanical Engineering, Columbia University, New York, NY, USA
| | - S K Agrawal
- Department of Mechanical Engineering, Columbia University, New York, NY, USA.
- Department of Rehabilitation and Regenerative Medicine, Columbia University, New York, NY, USA.
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10
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Massé-Alarie H, Shraim MA, Taylor JL, Hodges PW. Effects of different modalities of afferent stimuli of the lumbo-sacral area on control of lumbar paravertebral muscles. Eur J Neurosci 2022; 56:3687-3704. [PMID: 35478204 DOI: 10.1111/ejn.15677] [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: 12/09/2021] [Revised: 03/23/2022] [Accepted: 04/07/2022] [Indexed: 11/30/2022]
Abstract
Somatosensory feedback to the central nervous system is essential to plan, perform and refine spine motor control. However, the influence of somatosensory afferent input from the trunk on the motor output to trunk muscles has received little attention. The objective was to compare the effects of distinct modalities of afferent stimulation on the net motoneuron and corticomotor excitability of paravertebral muscles. Fourteen individuals were recruited. Modulation of corticospinal excitability (motor-evoked potential [MEP]) of paravertebral muscles was measured when afferent stimuli (cutaneous noxious and non-noxious, muscle contraction) were delivered to the trunk at 10 intervals prior to transcranial magnetic stimulation. Each peripheral stimulation was applied alone, and subsequent EMG modulation was measured to control for net motoneuron excitability. MEP modulation and MEP/EMG ratio were used as measures of corticospinal excitability with and without control of net motoneuron excitability, respectively. MEP and EMG modulation were smaller after evoked muscle contraction than after cutaneous noxious and non-noxious stimuli. MEP/EMG ratio was not different between stimulation types. Both MEP and EMG amplitudes were reduced after evoked muscle contraction, but not when expressed as MEP/EMG ratio. Noxious and non-noxious stimulation had limited impact on all variables. Distinct modalities of peripheral afferent stimulation of the lumbo-sacral area differently modulated responses of paravertebral muscles, but without an influence on corticospinal excitability with control of net motoneuron excitability. Muscle stimulation reduced paravertebral activity and was best explained by spinal mechanisms. The impact of afferent stimulation on back muscles differs from the effects reported for limb muscles.
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Affiliation(s)
- Hugo Massé-Alarie
- The University of Queensland, NHMRC Centre of Clinical Research Excellence in Spinal Pain, Injury & Health, School of Health & Rehabilitation Sciences, Brisbane, Qld, Australia.,Centre interdisciplinaire de recherche en réadaptation et intégration sociale (CIRRIS), Université Laval, Québec, Canada
| | - Muath A Shraim
- The University of Queensland, NHMRC Centre of Clinical Research Excellence in Spinal Pain, Injury & Health, School of Health & Rehabilitation Sciences, Brisbane, Qld, Australia
| | - Janet L Taylor
- School of Medical and Health Sciences, Edith Cowan University, Perth, WA, Australia.,Neuroscience Research Australia, Randwick, NSW, Australia
| | - Paul W Hodges
- The University of Queensland, NHMRC Centre of Clinical Research Excellence in Spinal Pain, Injury & Health, School of Health & Rehabilitation Sciences, Brisbane, Qld, Australia
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11
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Matsumoto A, Liang N, Ueda H, Irie K. Corticospinal Excitability of the Lower Limb Muscles During the Anticipatory Postural Adjustments: A TMS Study During Dart Throwing. Front Hum Neurosci 2021; 15:703377. [PMID: 34776899 PMCID: PMC8580880 DOI: 10.3389/fnhum.2021.703377] [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: 04/30/2021] [Accepted: 09/28/2021] [Indexed: 11/16/2022] Open
Abstract
Objective: To investigate whether the changes in the corticospinal excitability contribute to the anticipatory postural adjustments (APAs) in the lower limb muscles when performing the ballistic upper limb movement of the dart throwing. Methods: We examined the primary motor cortex (M1) excitability of the lower limb muscles [tibialis anterior (TA) and soleus (SOL) muscles] during the APA phase by using transcranial magnetic stimulation (TMS) in the healthy volunteers. The surface electromyography (EMG) of anterior deltoid, triceps brachii, biceps brachii, TA, and SOL muscles was recorded and the motor evoked potential (MEP) to TMS was recorded in the TA muscle along with the SOL muscle. TMS at the hotspot of the TA muscle was applied at the timings immediately prior to the TA onset. The kinematic parameters including the three-dimensional motion analysis and center of pressure (COP) during the dart throwing were also assessed. Results: The changes in COP and EMG of the TA muscle occurred preceding the dart throwing, which involved a slight elbow flexion followed by an extension. The correlation analysis revealed that the onset of the TA muscle was related to the COP change and the elbow joint flexion. The MEP amplitude in the TA muscle, but not that in the SOL muscle, significantly increased immediately prior to the EMG burst (100, 50, and 0 ms prior to the TA onset). Conclusion: Our findings demonstrate that the corticospinal excitability of the TA muscle increases prior to the ballistic upper limb movement of the dart throwing, suggesting that the corticospinal pathway contributes to the APA in the lower limb in a muscle-specific manner.
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Affiliation(s)
- Amiri Matsumoto
- Cognitive Motor Neuroscience, Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Nan Liang
- Cognitive Motor Neuroscience, Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Hajime Ueda
- Cognitive Motor Neuroscience, Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Keisuke Irie
- Cognitive Motor Neuroscience, Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan
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12
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Task- and Intensity-Dependent Modulation of Arm-Trunk Neural Interactions in the Corticospinal Pathway in Humans. eNeuro 2021; 8:ENEURO.0111-21.2021. [PMID: 34503966 PMCID: PMC8482852 DOI: 10.1523/eneuro.0111-21.2021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 08/16/2021] [Accepted: 08/19/2021] [Indexed: 12/02/2022] Open
Abstract
Most human movements require coordinated activation of multiple muscles. Although many studies reported associations between arm, leg, and trunk muscles during functional tasks, their neural interaction mechanisms still remain unclear. Therefore, the aim of our study was to investigate arm-trunk or arm-leg neural interactions in the corticospinal tract during different arm muscle contractions. Specifically, we examined corticospinal excitability of the erector spinae (ES; trunk extensor), rectus abdominis (RA; trunk flexor), and tibialis anterior (TA; leg) muscles while participants exerted: (1) wrist flexion and (2) wrist extension isometric contraction at various contraction intensity levels ranging from rest to 50% of maximal voluntary contraction (MVC) effort. Corticospinal excitability was assessed using motor evoked potentials (MEPs) elicited through motor cortex transcranial magnetic stimulation (TMS). Results showed that ES MEPs were facilitated even at low contractions (>5% MVC) during wrist flexion and extension, while stronger contractions (>25% MVC) were required to facilitate RA MEPs. The extent of facilitation of ES MEPs depended on contraction intensity of wrist extension, but not flexion. Moreover, TA MEPs were facilitated at low contractions (>5% MVC) during wrist flexion and extension, but contraction intensity dependence was only shown during stronger wrist extension contractions (>25% MVC). In conclusion, trunk extensor corticospinal excitability seems to depend on the task and the intensity of arm contraction, while this is not true for trunk flexor and leg muscles. Our study therefore demonstrated task- and intensity-dependent neural interactions of arm-trunk connections, which may underlie anatomic and/or functional substrates of these muscle pairs.
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13
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Rowland RS, Jenkinson N, Chiou SY. Age-Related Differences in Corticospinal Excitability and Anticipatory Postural Adjustments of the Trunk. Front Aging Neurosci 2021; 13:718784. [PMID: 34483887 PMCID: PMC8416077 DOI: 10.3389/fnagi.2021.718784] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 07/26/2021] [Indexed: 11/13/2022] Open
Abstract
Anticipatory postural adjustments (APAs) are a feedforward mechanism for the maintenance of postural stability and are delayed in old adults. We previously showed in young adults that APAs of the trunk induced by a fast shoulder movement were mediated, at least in part, by a cortical mechanism. However, it remains unclear the relationship between delayed APAs and motor cortical excitability in ageing. Using transcranial magnetic stimulation we examined motor evoked potentials (MEPs) of the erector spinae (ES) muscles in healthy young and old adults prior to a fast shoulder flexion task. A recognition reaction time (RRT) paradigm was used where participants responded to a visual stimulus by flexing their shoulders bilaterally as fast as possible. The activity of bilateral anterior deltoid (AD) and ES muscles was recorded using electromyography (EMG). The onset of AD and ES EMG was measured to represent RRT and APAs, respectively. We found increases in amplitudes of ES MEPs at 40 ms than 50 ms prior to the EMG onset of the AD in both groups. The amplitude of ES MEPs at 40 ms prior to the onset of AD EMG correlated with the onset of ES activity counterbalancing the perturbation induced by the shoulder task in the elderly participants only. Our findings suggest that timing of increasing corticospinal excitability prior to a self-paced perturbation becomes more relevant with ageing in modulating postural control of the trunk.
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Affiliation(s)
- Rebecca S Rowland
- School of Sport, Exercise, and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Ned Jenkinson
- School of Sport, Exercise, and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom.,Centre for Human Brain Health, University of Birmingham, Birmingham, United Kingdom.,Medical Research Council 'Versus' Arthritis Centre for Musculoskeletal Ageing Research, University of Birmingham, Birmingham, United Kingdom
| | - Shin-Yi Chiou
- School of Sport, Exercise, and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom.,Centre for Human Brain Health, University of Birmingham, Birmingham, United Kingdom.,Medical Research Council 'Versus' Arthritis Centre for Musculoskeletal Ageing Research, University of Birmingham, Birmingham, United Kingdom
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14
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Core Stability Exercises Yield Multiple Benefits for Patients with Chronic Stroke - Randomized Controlled Trial. Am J Phys Med Rehabil 2021; 101:314-323. [PMID: 34001840 DOI: 10.1097/phm.0000000000001794] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE This study examines the effect of core stability exercises on trunk control, core muscle strength, standing weight-bearing symmetry and balance confidence of people with chronic stroke. DESIGN This was an assessor-blinded randomized controlled trial involving 84 ambulatory patients with middle cerebral artery stroke, randomly assigned to three training groups. Two experimental groups practiced core stability exercises either on stable or unstable support surfaces. In contrast, the control group received standard physiotherapy. All the participants an hour-long training session a day, thrice a week over a six-week duration, and followed-up after 12 months. Trunk Impairment Scale, core muscle strength, weight-bearing asymmetry in standing and Activities-specific Balance Confidence scale were the outcome measures. RESULTS Compared to the control group, the two experimental groups demonstrated a significant improvement on all the outcome measures from baseline to post-training and from baseline to 12-month follow-up (P < 0.001). The two experimental groups demonstrated no significant difference between them on all the measures (P > 0.05). CONCLUSION Core stability exercises on stable and unstable support surfaces are equally beneficial in improving trunk control, core muscle strength, standing weight-bearing symmetry and balance confidence of ambulatory patients with chronic stroke than the standard physiotherapy.
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15
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Jiang N, Wang L, Huang Z, Li G. Mapping Responses of Lumbar Paravertebral Muscles to Single-Pulse Cortical TMS Using High-Density Surface Electromyography. IEEE Trans Neural Syst Rehabil Eng 2021; 29:831-840. [PMID: 33905333 DOI: 10.1109/tnsre.2021.3076095] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Motor evoked potential (MEP), which was elicited by transcranial magnetic stimulation (TMS), has been widely used to detect corticospinal projection from TMS cortical site to trunk muscles. It can help to find the stimulation hotspot in the scalp. However, it fails to precisely describe coordinated activities of trunk muscle groups with only single-channel myoelectric signal. In this study, we aimed to use high-density surface electromyography (sEMG) to explore the effect of cortical TMS on lumbar paravertebral muscles in healthy subjects. The cortical site at 1 cm anterior and 4 cm lateral to vertex was chosen to simulate using a single-pulse TMS with different intensities and forward-bending angles. A high-density electrode array (45 channels) was placed on the surface of lumbar paravertebral muscles to record sEMG signals during a TMS experiment. MEP signals elicited by TMS were extracted from 45-channel recordings and one topographic map of the MEP amplitudes with six spatial features was constructed at each sampling point. The results showed TMS could successfully evoke an oval area with high intensity in the MEP topographic map, while this area mainly located in ipsilateral side of the TMS site. Intensity features related to the high intensity area rose significantly with TMS intensity and forward-bending angle increasing, but location features showed no change. The optimal stimulation parameters were 80% of maximum stimulator output (MSO) for TMS intensity and 30/60 degree for forward-bending angle. This study provided a potentially effective mapping tool to explore the hotspot for transcranial stimulation on trunk muscles.
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16
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Chiou SY, Strutton PH. Crossed Corticospinal Facilitation Between Arm and Trunk Muscles Correlates With Trunk Control After Spinal Cord Injury. Front Hum Neurosci 2020; 14:583579. [PMID: 33192418 PMCID: PMC7645046 DOI: 10.3389/fnhum.2020.583579] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 09/22/2020] [Indexed: 11/13/2022] Open
Abstract
Objective: To investigate whether crossed corticospinal facilitation between arm and trunk muscles is preserved following spinal cord injury (SCI) and to elucidate these neural interactions for postural control during functional arm movements. Methods: Using transcranial magnetic stimulation (TMS) in 22 subjects with incomplete SCI motor evoked potentials (MEPs) in the erector spinae (ES) muscle were examined when the contralateral arm was at rest or performed 20% of maximal voluntary contraction (MVC) of biceps brachii (BB) or triceps brachii (TB). Trunk function was assessed with rapid shoulder flexion and forward-reaching tasks. Results: MEP amplitudes in ES were increased during elbow flexion in some subjects and this facilitatory effect was more prominent in subjects with thoracic SCI than in the subjects with cervical SCI. Those who showed the increased MEPs during elbow flexion had faster reaction times and quicker anticipatory postural adjustments of the trunk in the rapid shoulder flexion task. The onset of EMG activity in ES during the rapid shoulder flexion task correlated with the trunk excursion in forward-reaching. Conclusions: Our findings demonstrate that crossed corticospinal facilitation in the trunk muscles can be preserved after SCI and is reflected in trunk control during functional arm movements.
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Affiliation(s)
- Shin-Yi Chiou
- Sport, Exercise, and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham, Birmingham, United Kingdom.,The Nick Davey Laboratory, Division of Surgery, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Paul H Strutton
- The Nick Davey Laboratory, Division of Surgery, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, London, United Kingdom
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17
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Chiou SY, Morris L, Gou W, Alexander E, Gay E. Motor cortical circuits contribute to crossed facilitation of trunk muscles induced by rhythmic arm movement. Sci Rep 2020; 10:17067. [PMID: 33051482 PMCID: PMC7555543 DOI: 10.1038/s41598-020-74005-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 09/18/2020] [Indexed: 12/17/2022] Open
Abstract
Training of one limb improves performance of the contralateral, untrained limb, a phenomenon known as cross transfer. It has been used for rehabilitation interventions, i.e. mirror therapy, in people with neurologic disorders. However, it remains unknown whether training of the upper limb can induce the cross-transfer effect to the trunk muscles. Using transcranial magnetic stimulation over the primary motor cortex (M1) we examined motor evoked potentials (MEPs) in the contralateral erector spinae (ES) muscle before and after 30 min of unilateral arm cycling in healthy volunteers. ES MEPs were increased after the arm cycling. To understand the origin of this facilitatory effect, we examined short-interval intracrotical inhibition (SICI) and cervicomedullary MEPs (CMEPs) in neural populations controlling in the ES muscle. Notably, SICI reduced after the arm cycling, while CMEPs remained the same. Using bilateral transcranial direct current stimulation (tDCS) in conjunction with 20 min of the arm cycling, the amplitude of ES MEPs increased to a similar extent as with 30 min of the arm cycling alone. These findings demonstrate that a single session of unilateral arm cycling induces short-term plasticity in corticospinal projections to the trunk muscle in healthy humans. The changes are likely driven by cortical mechanisms.
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Affiliation(s)
- Shin-Yi Chiou
- School of Sport, Exercise, Rehabilitation Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK. .,Centre for Human Brain Health, University of Birmingham, Birmingham, UK.
| | - Laura Morris
- School of Sport, Exercise, Rehabilitation Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Weidong Gou
- School of Sport, Exercise, Rehabilitation Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Emma Alexander
- School of Sport, Exercise, Rehabilitation Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Eliot Gay
- School of Sport, Exercise, Rehabilitation Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
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18
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Farr BD, Ramos MT, Otto CM. The Penn Vet Working Dog Center Fit to Work Program: A Formalized Method for Assessing and Developing Foundational Canine Physical Fitness. Front Vet Sci 2020; 7:470. [PMID: 32903560 PMCID: PMC7438591 DOI: 10.3389/fvets.2020.00470] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 06/25/2020] [Indexed: 12/23/2022] Open
Abstract
Fit to Work is a formalized working dog foundational physical fitness assessment and development program. The Penn Vet Working Dog Center developed this program to address the needs of working dog handlers, trainers, and programs for simple, effective, and efficient methods to develop and assess working dog physical fitness. Fit to Work focuses on the foundational fitness modalities of strength, stability, mobility, and proprioception. The Penn Vet Working Dog Center piloted and refined this program over 3 months in a closed population of 31 working dogs in training. Fit to Work consists of posture development and maintenance, warm-up and cool-down routines, training exercises, and assessment methods. To simplify implementation for dogs and personnel, the foundational training program incorporates a discrete number of exercises, standardized progression steps, defined criteria for progression, and a reduced emphasis on learned behaviors. Fit to Work also enables safe and progressive assessment of foundational fitness through a tiered and inexpensive process. Future research will focus on validation of training and assessment methods, development of assessment standards, and correlation of physical fitness with operational performance.
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Affiliation(s)
- Brian D. Farr
- Army Medical Department Student Detachment, 187th Medical Battalion, Medical Professional Training Brigade, Joint Base San Antonio - Fort Sam Houston, San Antonio, TX, United States
- Penn Vet Working Dog Center, Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Meghan T. Ramos
- Penn Vet Working Dog Center, Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Cynthia M. Otto
- Penn Vet Working Dog Center, Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, United States
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19
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Silfies SP, Beattie P, Jordon M, Vendemia JMC. Assessing sensorimotor control of the lumbopelvic-hip region using task-based functional MRI. J Neurophysiol 2020; 124:192-206. [PMID: 32519579 DOI: 10.1152/jn.00288.2019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Recent brain imaging studies have suggested that cortical remodeling within sensorimotor regions are associated with persistent low back pain and may be a driving mechanism for the impaired neuromuscular control associated with this condition. This paper outlines a new approach for investigating cortical sensorimotor integration during the performance of small-amplitude lumbopelvic movements with functional MRI. Fourteen healthy right-handed participants were instructed in the lumbopelvic movement tasks performed during fMRI acquisition. Surface electromyography (EMG) collected on 8 lumbopelvic and thigh muscles captured organized patterns of muscle activation during the movement tasks. fMRI data were collected on 10 of 14 participants. Sensorimotor cortical activation across the tasks was identified using a whole brain analysis and further explored with regional analyses of key components of the cortical sensorimotor network. Head motion had low correlation to the tasks (r = -0.101 to 0.004) and head translation averaged 0.98 (0.59 mm) before motion correction. Patterns of activation of the key lumbopelvic and thigh musculature (average amplitude normalized 2-17%) were significantly different across tasks (P > 0.001). Neuroimaging demonstrated activation in key sensorimotor cortical regions that were consistent with motor planning and sensory feedback needed for performing the different tasks. This approach captures the specificity of lumbopelvic sensorimotor control using goal-based tasks (e.g., "lift your hip" vs. "contract your lumbar multifidus to 20% of maximum") performed within the confines of the scanner. Specific patterns of sensorimotor cortex activation appear to capture differences between bilateral and unilateral tasks during voluntary control of multisegmental movement in the lumbopelvic region.NEW & NOTEWORTHY We demonstrated the feasibility of using task-based functional magnetic resonance imaging (fMRI) protocols for acquiring the blood oxygen level-dependent (BOLD) response of key sensorimotor cortex regions during voluntary lumbopelvic movements. Our approach activated lumbopelvic muscles during small-amplitude movements while participants were lying supine in the scanner. Our data supports these tasks can be done with limited head motion and low correlation of head motion to the task. The approach provides opportunities for assessing the role of brain changes in persistent low back pain.
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Affiliation(s)
- Sheri P Silfies
- Doctoral Program in Physical Therapy, Department of Exercise Science, Arnold School of Public Health, University of South Carolina, Columbia, South Carolina.,McCausland Brain Imaging Center, University of South Carolina, Columbia, South Carolina
| | - Paul Beattie
- Doctoral Program in Physical Therapy, Department of Exercise Science, Arnold School of Public Health, University of South Carolina, Columbia, South Carolina
| | - Max Jordon
- Doctoral Program in Physical Therapy, Department of Exercise Science, Arnold School of Public Health, University of South Carolina, Columbia, South Carolina
| | - Jennifer M C Vendemia
- McCausland Brain Imaging Center, University of South Carolina, Columbia, South Carolina.,Institute for Mind and Brain, Department of Psychology, University of South Carolina, Columbia, South Carolina
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20
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Meier ML, Vrana A, Schweinhardt P. Low Back Pain: The Potential Contribution of Supraspinal Motor Control and Proprioception. Neuroscientist 2019; 25:583-596. [PMID: 30387689 PMCID: PMC6900582 DOI: 10.1177/1073858418809074] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Motor control, which relies on constant communication between motor and sensory systems, is crucial for spine posture, stability and movement. Adaptions of motor control occur in low back pain (LBP) while different motor adaption strategies exist across individuals, probably to reduce LBP and risk of injury. However, in some individuals with LBP, adapted motor control strategies might have long-term consequences, such as increased spinal loading that has been linked with degeneration of intervertebral discs and other tissues, potentially maintaining recurrent or chronic LBP. Factors contributing to motor control adaptations in LBP have been extensively studied on the motor output side, but less attention has been paid to changes in sensory input, specifically proprioception. Furthermore, motor cortex reorganization has been linked with chronic and recurrent LBP, but underlying factors are poorly understood. Here, we review current research on behavioral and neural effects of motor control adaptions in LBP. We conclude that back pain-induced disrupted or reduced proprioceptive signaling likely plays a pivotal role in driving long-term changes in the top-down control of the motor system via motor and sensory cortical reorganization. In the outlook of this review, we explore whether motor control adaptations are also important for other (musculoskeletal) pain conditions.
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Affiliation(s)
- Michael Lukas Meier
- Integrative Spinal Research, Department of
Chiropractic Medicine, University Hospital Balgrist, Zurich, Switzerland
| | - Andrea Vrana
- Integrative Spinal Research, Department of
Chiropractic Medicine, University Hospital Balgrist, Zurich, Switzerland
| | - Petra Schweinhardt
- Integrative Spinal Research, Department of
Chiropractic Medicine, University Hospital Balgrist, Zurich, Switzerland
- Alan Edwards Center for Research on Pain,
McGill University, Montreal, Quebec, Canada
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21
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Smith JA, Fisher BE. Anticipatory postural adjustments and spatial organization of motor cortex: evidence of adaptive compensations in healthy older adults. J Neurophysiol 2018; 120:2796-2805. [DOI: 10.1152/jn.00428.2018] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
During anticipated postural perturbations induced by limb movement, the central nervous system generates anticipatory postural adjustments (APAs) in the trunk and hip musculature to minimize disturbances to equilibrium. Age-related changes in functional organization of the nervous system may contribute to changes in APAs in healthy older adults. Here we examined if altered APAs of trunk/hip musculature in older adults are accompanied by changes in the representation of these muscles in motor cortex. Twelve healthy older adults, 5 with a history of falls and 7 nonfallers, were compared with 13 young adults. APAs were assessed during a mediolateral arm raise task in standing. Temporal organization of postural adjustments was quantified as latency of APAs in the contralateral external oblique, lumbar paraspinals, and gluteus medius relative to activation of the deltoid. Spatial organization was quantified as extent of synergistic coactivation between muscles. Volume and location of the muscle representations in motor cortex were mapped using transcranial magnetic stimulation. We found that older adults demonstrated significantly delayed APAs in the gluteus medius muscle. Spatial organization of the three muscles in motor cortex differed between groups, with the older adults demonstrating more lateral external oblique representation than the other two muscles. Separate comparisons of the faller and nonfaller subgroups with young adults indicated that nonfallers had the greatest delay in gluteus medius APAs and a reduced distance between the representational areas of the lumbar paraspinals and gluteus medius. This study indicates that altered spatial organization of motor cortex accompanies altered temporal organization of APA synergies in older adults. NEW & NOTEWORTHY Anticipatory postural adjustments are a critical component of postural control. Here we demonstrate that, in healthy older adults with and without a history of falls, delayed anticipatory postural adjustments in the hip musculature during mediolateral perturbations are accompanied by altered organization of trunk/hip muscle representation in motor cortex. The largest adaptations are evident in older adults with no history of falls.
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Affiliation(s)
- Jo Armour Smith
- Department of Physical Therapy, Crean College of Health and Behavioral Sciences, Chapman University, Irvine, California
- Neuroplasticity and Imaging Laboratory, Division of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, California
| | - Beth E. Fisher
- Neuroplasticity and Imaging Laboratory, Division of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, California
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22
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Kesar TM, Stinear JW, Wolf SL. The use of transcranial magnetic stimulation to evaluate cortical excitability of lower limb musculature: Challenges and opportunities. Restor Neurol Neurosci 2018; 36:333-348. [PMID: 29758954 DOI: 10.3233/rnn-170801] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Neuroplasticity is a fundamental yet relatively unexplored process that can impact rehabilitation of lower extremity (LE) movements. Transcranial magnetic stimulation (TMS) has gained widespread application as a non-invasive brain stimulation technique for evaluating neuroplasticity of the corticospinal pathway. However, a majority of TMS studies have been performed on hand muscles, with a paucity of TMS investigations focused on LE muscles. This perspective review paper proposes that there are unique methodological challenges associated with using TMS to evaluate corticospinal excitability of lower limb muscles. The challenges include: (1) the deeper location of the LE motor homunculus; (2) difficulty with targeting individual LE muscles during TMS; and (3) differences in corticospinal circuity controlling upper and lower limb muscles. We encourage future investigations that modify traditional methodological approaches to help address these challenges. Systematic TMS investigations are needed to determine the extent of overlap in corticomotor maps for different LE muscles. A simple, yet informative methodological solution involves simultaneous recordings from multiple LE muscles, which will provide the added benefit of observing how other relevant muscles co-vary in their responses during targeted TMS assessment directed toward a specific muscle. Furthermore, conventionally used TMS methods (e.g., determination of hot spot location and motor threshold) may need to be modified for TMS studies involving LE muscles. Additional investigations are necessary to determine the influence of testing posture as well as activation state of adjacent and distant LE muscles on TMS-elicited responses. An understanding of these challenges and solutions specific to LE TMS will improve the ability of neurorehabilitation clinicians to interpret TMS literature, and forge novel future directions for neuroscience research focused on elucidating neuroplasticity processes underlying locomotion and gait training.
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Affiliation(s)
- Trisha M Kesar
- Department of Rehabilitation Medicine, Division of Physical Therapy, Emory University, Atlanta, GA, USA
| | - James W Stinear
- Exercise Sciences, The University of Auckland, Auckland, New Zealand
| | - Steven L Wolf
- Department of Rehabilitation Medicine, Division of Physical Therapy, Emory University, Atlanta, GA, USA.,Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affair Medical Center, Decatur, GA, USA
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23
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Chiou SY, Strutton PH, Perez MA. Crossed corticospinal facilitation between arm and trunk muscles in humans. J Neurophysiol 2018; 120:2595-2602. [PMID: 29847230 DOI: 10.1152/jn.00178.2018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
A voluntary contraction of muscles with one arm increases the excitability of corticospinal projections to the contralateral resting arm, a phenomenon known as crossed facilitation. Although many motor tasks engage simultaneous activation of the arm and trunk, interactions between corticospinal projections targeting these segments remain largely unknown. Using transcranial magnetic stimulation over the trunk representation of the primary motor cortex, we examined motor-evoked potentials (MEPs) in the resting erector spinae (ES) muscle when the contralateral arm remained at rest or performed 20% of isometric maximal voluntary contraction (MVC) into index finger abduction, thumb abduction, elbow flexion, and elbow extension. We found that MEP size in the ES increased during all voluntary contractions, with greater facilitation occurring during elbow flexion and index finger abduction. To further examine the origin of changes in MEP size, we measured short-interval intracortical inhibition (SICI) and cervicomedullary MEPs (CMEPs) in the ES muscle during elbow flexion and index finger abduction and when the arm remained at rest. Notably, SICI decreased and CMEPs remained unchanged in the ES during both voluntary contractions compared with rest, suggesting a cortical origin for the effects. Our findings reveal crossed facilitatory interactions between trunk extensor and proximal and distal arm muscles, particularly for elbow flexor and index finger muscles, likely involving cortical mechanisms. These interactions might reflect the different role of these muscles during functionally relevant arm and trunk movements. NEW & NOTEWORTHY Many of the tasks of daily life involve simultaneous activation of the arm and trunk. We found that responses in the erector spinae muscles evoked by motor cortical stimulation increased in size during elbow flexion and extension and during index finger abduction and thumb abduction. Crossed facilitation with the trunk was more pronounced during elbow flexion and index finger abduction. These results might reflect the different role of these muscles during arm and trunk movements.
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Affiliation(s)
- Shin-Yi Chiou
- Faculty of Medicine, The Nick Davey Laboratory, Division of Surgery, Department of Surgery and Cancer, Imperial College London , London , United Kingdom.,Department of Physical Medicine and Rehabilitation, Systems Neuroscience Institute, University of Pittsburgh, Pennsylvania
| | - Paul H Strutton
- Faculty of Medicine, The Nick Davey Laboratory, Division of Surgery, Department of Surgery and Cancer, Imperial College London , London , United Kingdom
| | - Monica A Perez
- Department of Physical Medicine and Rehabilitation, Systems Neuroscience Institute, University of Pittsburgh, Pennsylvania.,Department of Neurological Surgery, The Miami Project to Cure Paralysis, University of Miami , Miami, Florida.,Bruce W. Carter Department of Veterans Affairs Medical Center, Miami, Florida
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24
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Chiou SY, Hurry M, Reed T, Quek JX, Strutton PH. Cortical contributions to anticipatory postural adjustments in the trunk. J Physiol 2018; 596:1295-1306. [PMID: 29368403 DOI: 10.1113/jp275312] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 01/17/2018] [Indexed: 12/24/2022] Open
Abstract
KEY POINTS Increases in activity of trunk muscles that occur prior to, or concurrent with, a voluntary limb movement are termed anticipatory postural adjustments (APAs). APAs are important for maintaining postural stability in response to perturbations but the neural mechanisms underlying APAs remain unclear. Our results showed that corticospinal excitability of erector spinae (ES) muscle increased at 40 ms prior to rapid shoulder flexion, with a reduction in intracortical inhibition and no change in spinal excitability. Changes in corticospinal excitability were observed in ES, with similar excitability profiles between standing and lying positions, but were not observed in rectus abdominis. We suggest that the neural control of postural adjustments involves changes at a cortical level, which in part are due to reduced inhibition. ABSTRACT Voluntary limb movements are associated with increases in trunk muscle activity, some of which occur within a time window considered too fast to be induced by sensory feedback; these increases are termed anticipatory postural adjustments (APAs). Although it is known that the function of APAs is to maintain postural stability in response to perturbations, excitability of the corticospinal projections to the trunk muscles during the APAs remains unclear. Thirty-four healthy subjects performed rapid shoulder flexion in response to a visual cue in standing and lying positions. Transcranial magnetic stimulation (TMS) was delivered over the trunk motor cortex to examine motor evoked potentials (MEPs) in erector spinae (ES) and in rectus abdominis (RA) muscles at several time points prior to the rise in electromyographic activity (EMG) of anterior deltoid (AD) muscle. TMS was also used to assess short-interval intracortical inhibition (SICI) and cervicomedullary MEPs (CMEPs) in ES in the standing position. MEPs in ES were larger at time points closer to the rise in AD EMG in both standing and lying positions, whereas MEPs in RA did not differ over the time course examined. Notably, SICI was reduced at time points closer to the rise in AD EMG, with no change in CMEPs. Our results demonstrate that increasing excitability of corticospinal projections to the trunk muscles prior to a voluntary limb movement is likely to be cortical in origin and is muscle specific.
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Affiliation(s)
- Shin-Yi Chiou
- The Nick Davey Laboratory, Division of Surgery, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, UK
| | - Madeleine Hurry
- The Nick Davey Laboratory, Division of Surgery, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, UK
| | - Thomas Reed
- The Nick Davey Laboratory, Division of Surgery, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, UK
| | - Jing Xiao Quek
- The Nick Davey Laboratory, Division of Surgery, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, UK
| | - Paul H Strutton
- The Nick Davey Laboratory, Division of Surgery, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, UK
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25
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Sasaki A, Milosevic M, Sekiguchi H, Nakazawa K. Evidence for existence of trunk-limb neural interaction in the corticospinal pathway. Neurosci Lett 2018; 668:31-36. [PMID: 29309857 DOI: 10.1016/j.neulet.2018.01.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 12/23/2017] [Accepted: 01/04/2018] [Indexed: 10/18/2022]
Abstract
In humans, trunk muscles have an essential role in postural control as well as walking. However, little is known about the mechanisms of interaction with different muscles, especially related to how trunk muscles interact with the limbs. Contraction of muscles can modulate the corticospinal excitability not only of the contracted muscle, but also of other muscles even in the remote segments of the body. However, "remote effect" mechanism has only been examined for inter-limb interactions. The aim of our current study was to test if there are trunk-limb interactions in the corticospinal pathways. We examined corticospinal excitability of: (a) trunk muscles at rest when hands, legs and jaw muscles were contracted and; (b) hand, leg, and jaw muscles at rest when trunk muscles were contracted. We measured motor evoked potentials elicited using transcranial magnetic stimulation in the rectus abdominis, flexor digitorum superficialis, masseter, tibialis anterior muscles under the following experimental conditions: (1) participants remained relaxed (Rest); (2) during trunk contraction (Trunk); (3) during bilateral hand clenching (Hands); (4) during jaw clenching (Jaw); and (5) during bilateral ankle dorsiflexion (Legs). Each condition was performed at three different stimulation intensities and conditions were randomized between participants. We found that voluntary contraction of trunk muscle facilitated the corticospinal excitability of upper-limb and lower-limb muscles during rest state. Furthermore, voluntary contraction of upper-limb muscle also facilitated the corticospinal excitability of trunk muscles during rest state. Overall, these results suggest the existence of trunk-limb interaction in the corticospinal pathway, which is likely depended on proximity of the trunk and limb representation in the motor cortex.
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Affiliation(s)
- Atsushi Sasaki
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan
| | - Matija Milosevic
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan.
| | - Hirofumi Sekiguchi
- Sports & Health Management Program, Faculty of Business and Information Sciences, Jobu University, 634-1 Toyazukamachi, Isesaki, Gunma, 372-8588, Japan
| | - Kimitaka Nakazawa
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan
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26
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Modulation of Corticospinal Excitability of Trunk Muscles in Preparation of Rapid Arm Movement. Neuroscience 2018; 369:231-241. [DOI: 10.1016/j.neuroscience.2017.11.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Revised: 11/14/2017] [Accepted: 11/15/2017] [Indexed: 12/22/2022]
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27
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Smith JA, Albishi A, Babikian S, Asavasopon S, Fisher BE, Kutch JJ. The motor cortical representation of a muscle is not homogeneous in brain connectivity. Exp Brain Res 2017. [PMID: 28631147 DOI: 10.1007/s00221-017-5011-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Functional connectivity patterns of the motor cortical representational area of single muscles have not been extensively mapped in humans, particularly for the axial musculature. Functional connectivity may provide a neural substrate for adaptation of muscle activity in axial muscles that have both voluntary and postural functions. The purpose of this study was to combine brain stimulation and neuroimaging to both map the cortical representation of the external oblique (EO) in primary motor cortex (M1) and supplementary motor area (SMA), and to establish the resting-state functional connectivity associated with this representation. Motor-evoked potentials were elicited from the EO muscle in stimulation locations encompassing M1 and SMA. The coordinates of locations with the largest motor-evoked potentials were confirmed with task-based fMRI imaging during EO activation. The M1 and SMA components of the EO representation demonstrated significantly different resting-state functional connectivity with other brain regions: the SMA representation of the EO muscle was significantly more connected to the putamen and cerebellum, and the M1 representation of the EO muscle was significantly more connected to somatosensory cortex and the superior parietal lobule. This study confirms the representation of a human axial muscle in M1 and SMA, and demonstrates for the first time that different parts of the cortical representation of a human axial muscle have resting-state functional connectivity with distinct brain regions. Future studies can use the brain regions of interest we have identified here to test the association between resting-state functional connectivity and control of the axial muscles.
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Affiliation(s)
- Jo Armour Smith
- Division of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, CA, USA
- Department of Physical Therapy, Chapman University, Irvine, CA, USA
| | - Alaa Albishi
- Division of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, CA, USA
- Department of Rehabilitation Sciences-Physical Therapy Division, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Sarine Babikian
- Department of Mechanical Engineering, University of Southern California, Los Angeles, CA, USA
| | - Skulpan Asavasopon
- Division of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, CA, USA
- Department of Physical Therapy, Loma Linda University, Loma Linda, CA, USA
| | - Beth E Fisher
- Division of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, CA, USA
- Department of Neurology, University of Southern California, Los Angeles, CA, USA
| | - Jason J Kutch
- Division of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, CA, USA.
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28
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Jean-Charles L, Nepveu JF, Deffeyes JE, Elgbeili G, Dancause N, Barthélemy D. Interhemispheric interactions between trunk muscle representations of the primary motor cortex. J Neurophysiol 2017; 118:1488-1500. [PMID: 28615339 DOI: 10.1152/jn.00778.2016] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 06/06/2017] [Accepted: 06/08/2017] [Indexed: 11/22/2022] Open
Abstract
Unilateral arm movements require trunk stabilization through bilateral contraction of axial muscles. Interhemispheric interactions between primary motor cortices (M1) could enable such coordinated contractions, but these mechanisms are largely unknown. Using transcranial magnetic stimulation (TMS), we characterized interhemispheric interactions between M1 representations of the trunk-stabilizing muscles erector spinae at the first lumbar vertebra (ES L1) during a right isometric shoulder flexion. These interactions were compared with those of the anterior deltoid (AD), the main agonist in this task, and the first dorsal interosseous (FDI). TMS over the right M1 elicited ipsilateral silent periods (iSP) in all three muscles on the right side. In ES L1, but not in AD or FDI, ipsilateral motor evoked potential (iMEP) could precede the iSP or replace it. iMEP amplitude was not significantly different whether ES L1 was used to stabilize the trunk or was voluntarily contracted. TMS at the cervicomedullary junction showed that the size of cervicomedullary evoked potential was unchanged during the iSP but increased during iMEP, suggesting that the iSP, but not the iMEP, is due to intracortical mechanisms. Using a dual-coil paradigm with two coils over the left and right M1, interhemispheric inhibition could be evoked at interstimulus intervals of 6 ms in ES L1 and 8 ms in AD and FDI. Together, these results suggest that interhemispheric inhibition is dominant when axial muscles are involved in a stabilizing task. The ipsilateral facilitation could be evoked by ipsilateral or subcortical pathways and could be used depending on the role axial muscles play in the task.NEW & NOTEWORTHY The mechanisms involved in the bilateral coordination of axial muscles during unilateral arm movement are poorly understood. We thus investigated the nature of interhemispheric interactions in axial muscles during arm motor tasks in healthy subjects. By combining different methodologies, we showed that trunk muscles receive both inhibitory and facilitatory cortical outputs during activation of arm muscles. We propose that inhibition may be conveyed mainly through interhemispheric mechanisms and facilitation by subcortical mechanisms or ipsilateral pathways.
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Affiliation(s)
- Loyda Jean-Charles
- Département de Neurosciences, Faculté de Médecine, Université de Montréal, Montreal, Quebec, Canada.,Centre de recherche interdisciplinaire en réadaptation du Montréal métropolitain, site de l'Institut de réadaptation Gingras-Lindsay-de-Montréal, Montreal, Quebec, Canada
| | - Jean-Francois Nepveu
- Département de Neurosciences, Faculté de Médecine, Université de Montréal, Montreal, Quebec, Canada.,Centre de recherche interdisciplinaire en réadaptation du Montréal métropolitain, site de l'Institut de réadaptation Gingras-Lindsay-de-Montréal, Montreal, Quebec, Canada
| | - Joan E Deffeyes
- Département de Neurosciences, Faculté de Médecine, Université de Montréal, Montreal, Quebec, Canada.,Centre de recherche interdisciplinaire en réadaptation du Montréal métropolitain, site de l'Institut de réadaptation Gingras-Lindsay-de-Montréal, Montreal, Quebec, Canada
| | - Guillaume Elgbeili
- Recherche en Schizophrénie et troubles neurodéveloppementaux, Institut universitaire en santé mentale Douglas, Montreal, Quebec, Canada
| | - Numa Dancause
- Département de Neurosciences, Faculté de Médecine, Université de Montréal, Montreal, Quebec, Canada
| | - Dorothy Barthélemy
- Centre de recherche interdisciplinaire en réadaptation du Montréal métropolitain, site de l'Institut de réadaptation Gingras-Lindsay-de-Montréal, Montreal, Quebec, Canada; .,Ecole de réadaptation, Faculté de Médecine, Université de Montréal, Montreal, Quebec, Canada; and
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