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Rimac J, Jančuljak D, Kovač B, Jovičić M, Forjan J. Reflex Responses in Muscles of the Lower Extremities Elicited by Transcutaneous Stimulation of Cauda Equina: Part 1. Methodology and Normative Data. J Clin Neurophysiol 2024:00004691-990000000-00135. [PMID: 38857374 DOI: 10.1097/wnp.0000000000001088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2024] Open
Abstract
INTRODUCTION Transcutaneous electrical stimulation is used to stimulate the dorsal roots of the cauda equina. Multiple elicited responses recorded in the lower extremity muscles are called posterior root muscle reflexes (PRMRs). Normal PRMR values in the muscles of healthy lower extremities have yet to be determined. METHODS Thirty subjects without known lumbosacral spinal root illness were included in this study. Subsequently, they were subjected to transcutaneous electrical stimulation of the cauda equina. Posterior root muscle reflex was recorded in the four muscle groups of both lower extremities. We elicited multiple PRMR and examined their characteristics in order to establish normal electrophysiological parameter values. RESULTS Posterior root muscle reflex was successfully elicited in the tibialis anterior (96.7%), gastrocnemius (100%), quadriceps femoris (93.3%), and hamstring (96.7%). No statistically significant differences were found in the intensity of stimulation, latencies, or area under the PRMR between the right and left leg muscles. The area under PRMR varied significantly among the participants. Higher body weight and abdominal girth showed a significant positive correlation with stimulation intensity for eliciting PRMR, and a significant negative correlation with the area under PRMR. Older age showed a significant negative correlation with the success of eliciting PRMR and the area under the PRMR. CONCLUSIONS Posterior root muscle reflex is a noninvasive and successful method for eliciting selective reflex responses of cauda equina posterior roots. Obtained values could be used in future studies to evaluate the utility of this methodology in clinical practice. This methodology could improve testing of the proximal lumbosacral nervous system functional integrity.
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Affiliation(s)
- Julija Rimac
- Department of Neurology, National Memorial Hospital "Dr. Juraj Njavro" Vukovar, Vukovar, Croatia
| | - Davor Jančuljak
- Neurology Clinic, Osijek Clinical Hospital Center, Osijek, Croatia
- Department of Neurology and Neurosurgery, Faculty of Medicine Osijek, University of Josip Juraj Strossmayer in Osijek, Osijek, Croatia
| | - Biserka Kovač
- Neurology Clinic, Osijek Clinical Hospital Center, Osijek, Croatia
- Department of Neurology, Faculty of Dental Medicine and Health Osijek, University of Josip Juraj Strossmayer in Osijek, Osijek, Croatia; and
| | - Miloš Jovičić
- Department of Neurology, National Memorial Hospital "Dr. Juraj Njavro" Vukovar, Vukovar, Croatia
| | - Josipa Forjan
- Department of Quantitative Methods and Informatics, Faculty of Economics in Osijek, Josip Juraj Strossmayer University in Osijek, Osijek, Croatia
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Dirks CAH, Bachmann CG. From brain to spinal cord: neuromodulation by direct current stimulation and its promising effects as a treatment option for restless legs syndrome. Front Neurol 2024; 15:1278200. [PMID: 38333606 PMCID: PMC10850250 DOI: 10.3389/fneur.2024.1278200] [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: 08/15/2023] [Accepted: 01/09/2024] [Indexed: 02/10/2024] Open
Abstract
Neuromodulation is a fast-growing field of mostly non-invasive therapies, which includes spinal cord stimulation (SCS), transcranial direct current stimulation (tDCS), vagal nerve stimulation (VNS), peripheral nerve stimulation, transcranial magnetic stimulation (TMS) and transcutaneous spinal direct current stimulation (tsDCS). This narrative review offers an overview of the therapy options, especially of tDCS and tsDCS for chronic pain and spinal cord injury. Finally, we discuss the potential of tsDCS in Restless Legs Syndrome as a promising non-invasive, alternative therapy to medication therapy.
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Hassan AB, Salihu AT, Masta MA, Gunn H, Marsden J, Abdullahi A, Ahmad RY, Danazumi MS. Effect of transcutaneous spinal direct current stimulation on spasticity in upper motor neuron conditions: a systematic review and meta-analysis. Spinal Cord 2023; 61:587-599. [PMID: 37640926 DOI: 10.1038/s41393-023-00928-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 08/02/2023] [Accepted: 08/16/2023] [Indexed: 08/31/2023]
Abstract
STUDY DESIGN A systematic review and meta-analysis of clinical trials. OBJECTIVES To determine the effect of non-invasive transcutaneous spinal direct current stimulation (tsDCS) on spasticity, activity limitations and participation restrictions in various upper motor neuron diseases. METHODS Six databases including CINAHL plus, Cochrane CENTRAL, Embase, MEDLINE, SCOPUS and Web of Science were searched for the relevant records from January 2008 to December 2022. Two reviewers independently selected and extracted data on spasticity, activity limitations and participation restrictions. The risk of bias was evaluated using the PEDro scale while the GRADE approach established the certainty of the evidence. RESULTS Eleven studies were identified of which 5 (45.5%) were rated as having a low risk of bias and 8 (72.7%) were meta-analyzed. The meta-analyses did not show any significant differences between cathodal (SMD = -0.67, 95% CI = -1.50 to 0.15, P = 0.11, I2 = 75%, 6 RCTs) or anodal (SMD = 0.11, 95% CI = -0.43 to -0.64, p = 0.69, I2 = 0%, 2 RCTs) and sham tsDCS for spasticity. There was also no significant difference between active and sham tsDCS for activity limitations (SMD = -0.42, 95% CI = -0.04 to 0.21, p = 0.2, I2 = 0%, 2 RCTs) and participation restrictions (MD = -8.10, 95% CI = -18.02 to 1.82, p = 0.11, 1 RCT). CONCLUSIONS The meta-analysis of the available evidence provides an uncertain estimate of the effect of cathodal tsDCS on spasticity, activity limitation and participation restriction. It might be very helpful, or it may make no difference at all. However, considering the level of the evidence and the limitation in the quality of the majority of the included studies, further well-designed research may likely change the estimate of effect. TRIAL REGISTRATION PROSPERO CRD42021245601.
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Affiliation(s)
- Auwal B Hassan
- Department of Medical Rehabilitation (Physiotherapy), Faculty of Allied Health Sciences, College of Medical Sciences, University of Maiduguri, Maiduguri, Borno State, Nigeria
| | - Abubakar T Salihu
- Department of Physiotherapy, Monash University, Melbourne, VIC, Australia
| | - Mamman A Masta
- Department of Medical Rehabilitation (Physiotherapy), Faculty of Allied Health Sciences, College of Medical Sciences, University of Maiduguri, Maiduguri, Borno State, Nigeria
| | - Hilary Gunn
- Peninsula Allied Health Centre, University of Plymouth, Plymouth, UK
| | - Jonathan Marsden
- Peninsula Allied Health Centre, University of Plymouth, Plymouth, UK
| | - Auwal Abdullahi
- Department of Physiotherapy, Bayero University Kano, Kano, Nigeria
| | - Rufa'i Y Ahmad
- Department of Physiotherapy, Bayero University Kano, Kano, Nigeria
| | - Musa S Danazumi
- Discipline of Physiotherapy, School of Allied Health, Human Services and Sport, College of Sciences, Health and Engineering, La Trobe University, Bundoora, VIC, 3085, Australia.
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Bikson M, Ganho-Ávila A, Datta A, Gillick B, Joensson MG, Kim S, Kim J, Kirton A, Lee K, Marjenin T, Onarheim B, Rehn EM, Sack AT, Unal G. Limited output transcranial electrical stimulation 2023 (LOTES-2023): Updates on engineering principles, regulatory statutes, and industry standards for wellness, over-the-counter, or prescription devices with low risk. Brain Stimul 2023; 16:840-853. [PMID: 37201865 PMCID: PMC10350287 DOI: 10.1016/j.brs.2023.05.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 05/09/2023] [Accepted: 05/13/2023] [Indexed: 05/20/2023] Open
Abstract
The objective and scope of this Limited Output Transcranial Electrical Stimulation 2023 (LOTES-2023) guidance is to update the previous LOTES-2017 guidance. These documents should therefore be considered together. The LOTES provides a clearly articulated and transparent framework for the design of devices providing limited output (specified low-intensity range) transcranial electrical stimulation for a variety of intended uses. These guidelines can inform trial design and regulatory decisions, but most directly inform manufacturer activities - and hence were presented in LOTES-2017 as "Voluntary industry standard for compliance controlled limited output tES devices". In LOTES-2023 we emphasize that these standards are largely aligned across international standards and national regulations (including those in USA, EU, and South Korea), and so might be better understood as "Industry standards for compliance controlled limited output tES devices". LOTES-2023 is therefore updated to reflect a consensus among emerging international standards, as well as best available scientific evidence. "Warnings" and "Precautions" are updated to align with current biomedical evidence and applications. LOTES standards applied to a constrained device dose range, but within this dose range and for different use-cases, manufacturers are responsible to conduct device-specific risk management.
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Affiliation(s)
- Marom Bikson
- Department of Biomedical Engineering, The City College of New York, New York, NY, United States.
| | - Ana Ganho-Ávila
- Center for Research in Neuropsychology and Cognitive Behavioral Intervention-CINEICC, Faculty of Psychology and Educational Sciences, University of Coimbra, Coimbra, Portugal
| | - Abhishek Datta
- Research and Development, Soterix Medical Inc., Woodbridge, NJ, United States
| | - Bernadette Gillick
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | | | - Sungjin Kim
- Ybrain Research Institute, Seongnam-si, Gyeonggi-do, South Korea
| | - Jinuk Kim
- Ybrain Research Institute, Seongnam-si, Gyeonggi-do, South Korea
| | - Adam Kirton
- Departments of Pediatrics and Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Kiwon Lee
- Ybrain Research Institute, Seongnam-si, Gyeonggi-do, South Korea
| | | | - Balder Onarheim
- Research and Development, PlatoScience ApS, Copenhagen, Denmark
| | - Erik M Rehn
- Research and Development, Flow Neuroscience, Malmo, Skane Lan, Sweden
| | - Alexander T Sack
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Gozde Unal
- Department of Biomedical Engineering, The City College of New York, New York, NY, United States.
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Guidetti M, Giannoni-Luza S, Bocci T, Pacheco-Barrios K, Bianchi AM, Parazzini M, Ionta S, Ferrucci R, Maiorana NV, Verde F, Ticozzi N, Silani V, Priori A. Modeling Electric Fields in Transcutaneous Spinal Direct Current Stimulation: A Clinical Perspective. Biomedicines 2023; 11:biomedicines11051283. [PMID: 37238953 DOI: 10.3390/biomedicines11051283] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/12/2023] [Accepted: 04/21/2023] [Indexed: 05/28/2023] Open
Abstract
Clinical findings suggest that transcutaneous spinal direct current stimulation (tsDCS) can modulate ascending sensitive, descending corticospinal, and segmental pathways in the spinal cord (SC). However, several aspects of the stimulation have not been completely understood, and realistic computational models based on MRI are the gold standard to predict the interaction between tsDCS-induced electric fields and anatomy. Here, we review the electric fields distribution in the SC during tsDCS as predicted by MRI-based realistic models, compare such knowledge with clinical findings, and define the role of computational knowledge in optimizing tsDCS protocols. tsDCS-induced electric fields are predicted to be safe and induce both transient and neuroplastic changes. This could support the possibility to explore new clinical applications, such as spinal cord injury. For the most applied protocol (2-3 mA for 20-30 min, active electrode over T10-T12 and the reference on the right shoulder), similar electric field intensities are generated in both ventral and dorsal horns of the SC at the same height. This was confirmed by human studies, in which both motor and sensitive effects were found. Lastly, electric fields are strongly dependent on anatomy and electrodes' placement. Regardless of the montage, inter-individual hotspots of higher values of electric fields were predicted, which could change when the subjects move from a position to another (e.g., from the supine to the lateral position). These characteristics underlines the need for individualized and patient-tailored MRI-based computational models to optimize the stimulation protocol. A detailed modeling approach of the electric field distribution might contribute to optimizing stimulation protocols, tailoring electrodes' configuration, intensities, and duration to the clinical outcome.
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Affiliation(s)
- Matteo Guidetti
- Aldo Ravelli Research Center for Neurotechnology and Experimental Neurotherapeutics, Department of Health Sciences, University of Milan, 20142 Milan, Italy
- Department of Electronics, Information and Bioengineering, Politecnico di Milano, 20133 Milan, Italy
| | - Stefano Giannoni-Luza
- Sensory-Motor Lab (SeMoLa), Department of Ophthalmology-University of Lausanne, Jules Gonin Eye Hospital/Fondation Asile des Aveugles, 1015 Lausanne, Switzerland
| | - Tommaso Bocci
- Aldo Ravelli Research Center for Neurotechnology and Experimental Neurotherapeutics, Department of Health Sciences, University of Milan, 20142 Milan, Italy
- III Neurology Clinic, ASST-Santi Paolo e Carlo University Hospital, 20142 Milan, Italy
| | - Kevin Pacheco-Barrios
- Neuromodulation Center and Center for Clinical Research Learning, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Boston, MA 02129, USA
- Unidad de Investigación para la Generación y Síntesis de Evidencias en Salud, Universidad San Ignacio de Loyola, Vicerrectorado de Investigación, Lima 15024, Peru
| | - Anna Maria Bianchi
- Department of Electronics, Information and Bioengineering, Politecnico di Milano, 20133 Milan, Italy
| | - Marta Parazzini
- Istituto di Elettronica e di Ingegneria Dell'Informazione e delle Telecomunicazioni (IEIIT), Consiglio Nazionale delle Ricerche (CNR), 10129 Milan, Italy
| | - Silvio Ionta
- Sensory-Motor Lab (SeMoLa), Department of Ophthalmology-University of Lausanne, Jules Gonin Eye Hospital/Fondation Asile des Aveugles, 1015 Lausanne, Switzerland
| | - Roberta Ferrucci
- III Neurology Clinic, ASST-Santi Paolo e Carlo University Hospital, 20142 Milan, Italy
- Department of Oncology and Hematology, University of Milan, 20122 Milan, Italy
| | - Natale Vincenzo Maiorana
- Aldo Ravelli Research Center for Neurotechnology and Experimental Neurotherapeutics, Department of Health Sciences, University of Milan, 20142 Milan, Italy
| | - Federico Verde
- Department of Neurology, Istituto Auxologico Italiano IRCCS, 20149 Milan, Italy
- Department of Pathophysiology and Transplantation, 'Dino Ferrari' Center, Università degli Studi di Milano, 20122 Milan, Italy
| | - Nicola Ticozzi
- Department of Neurology, Istituto Auxologico Italiano IRCCS, 20149 Milan, Italy
- Department of Pathophysiology and Transplantation, 'Dino Ferrari' Center, Università degli Studi di Milano, 20122 Milan, Italy
| | - Vincenzo Silani
- Department of Neurology, Istituto Auxologico Italiano IRCCS, 20149 Milan, Italy
- Department of Pathophysiology and Transplantation, 'Dino Ferrari' Center, Università degli Studi di Milano, 20122 Milan, Italy
| | - Alberto Priori
- Aldo Ravelli Research Center for Neurotechnology and Experimental Neurotherapeutics, Department of Health Sciences, University of Milan, 20142 Milan, Italy
- III Neurology Clinic, ASST-Santi Paolo e Carlo University Hospital, 20142 Milan, Italy
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Koseki T, Kudo D, Yoshida K, Nito M, Takano K, Jin M, Tanabe S, Sato T, Katoh H, Yamaguchi T. Combined neuromuscular electrical stimulation and transcutaneous spinal direct current stimulation increases motor cortical plasticity in healthy humans. Front Neurosci 2023; 16:1034451. [PMID: 37091256 PMCID: PMC10115158 DOI: 10.3389/fnins.2022.1034451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 12/28/2022] [Indexed: 01/15/2023] Open
Abstract
IntroductionNeuromuscular electrical stimulation (NMES) induces neural plasticity of the central nervous system (CNS) and improves motor function in patients with CNS lesions. However, the extended stimulus duration of NMES reduces its clinical applicability. Transcutaneous spinal direct current stimulation (tsDCS), which increases afferent input, may enhance the effects and reduce the stimulus duration of NMES. This study investigated the excitability of the motor cortex, somatosensory cortex, and spinal motor neurons after the combined stimulation of NMES and tsDCS.MethodsAmong the 55 participants in this study, 24 were allocated to experiment 1, 15 to experiment 2, and 16 to experiment 3. They received intervention for 20 min on different days: (1) NMES combined with tsDCS (NMES + tsDCS), (2) NMES combined with sham tsDCS (NMES + sham tsDCS), and (3) sham NMES combined with tsDCS (sham NMES + tsDCS). NMES was delivered to the right common peroneal nerve at 25 Hz with the intensity at 120% of the motor threshold. For tsDCS, the cathodal electrode was positioned on the thoracic 10th–12th vertebral levels, and the anodal electrode was located on the right shoulder. The stimulus intensity was 2.5 mA. In experiment 1, motor evoked potentials (MEPs) and short-latency intracortical inhibition (SICI) were measured by transcranial magnetic stimulation up to 60 min after stimulation. The spinal motor neurons’ excitability was assessed by recording the posterior root muscle reflex (PRMR) induced via transcutaneous spinal cord stimulation in experiment 2, and the primary somatosensory cortex excitability was evaluated by recording the somatosensory evoked potentials (SEPs) in experiment 3 up to 15 min after stimulation.ResultsCompared to before the stimulation, NMES + tsDCS significantly increased MEP for 60 min or more, and significantly decreased SICI immediately after. Conversely contrast, the PRMR significantly decreased immediately after, and SEPs were unchanged.DiscussionThese results suggest that simultaneous afferent inputs from different stimulus positions critically induce primary motor cortex plasticity. The combined stimulation of NMES with tsDCS may facilitate the development of a new neurorehabilitation technique.
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Affiliation(s)
- Tadaki Koseki
- Graduate School of Health Sciences, Yamagata Prefectural University of Health Sciences, Yamagata, Japan
| | - Daisuke Kudo
- Graduate School of Health Sciences, Yamagata Prefectural University of Health Sciences, Yamagata, Japan
- Department of Physical Therapy, Yamagata Prefectural University of Health Sciences, Yamagata, Japan
| | - Kaito Yoshida
- Graduate School of Health Sciences, Yamagata Prefectural University of Health Sciences, Yamagata, Japan
| | - Mitsuhiro Nito
- Department of Anatomy and Structural Science, Yamagata University School of Medicine, Yamagata, Japan
| | - Keita Takano
- Graduate School of Health Sciences, Yamagata Prefectural University of Health Sciences, Yamagata, Japan
| | - Masafumi Jin
- Graduate School of Health Sciences, Yamagata Prefectural University of Health Sciences, Yamagata, Japan
| | - Shigeo Tanabe
- Faculty of Rehabilitation, School of Health Sciences, Fujita Health University, Toyoake, Japan
| | - Toshiaki Sato
- Department of Occupational Therapy, Yamagata Prefectural University of Health Sciences, Yamagata, Japan
| | - Hiroshi Katoh
- Department of Physical Therapy, Yamagata Prefectural University of Health Sciences, Yamagata, Japan
| | - Tomofumi Yamaguchi
- Department of Physical Therapy, Faculty of Health Science, Juntendo University, Tokyo, Japan
- *Correspondence: Tomofumi Yamaguchi,
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Pereira M, Fernandes SR, Miranda PC, de Carvalho M. Lumbar trans-spinal direct current stimulation: A modeling-experimental approach to dorsal root ganglia stimulation. Front Neurosci 2022; 16:1041932. [PMID: 36570853 PMCID: PMC9773993 DOI: 10.3389/fnins.2022.1041932] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Accepted: 11/23/2022] [Indexed: 12/14/2022] Open
Abstract
Introduction The excitability of spinal motor neurons (MN) can be altered through subthreshold currents, such as transcutaneous spinal direct-current stimulation (tsDCS). Current evidence shows that tsDCS can interfere with ascending somatosensory pathways and lower motor neurons' (LMN) excitability, which points to its therapeutic potential for repairing altered spinal responses. We aim to define the best tsDCS montage for maximizing the electric field (E-field) in the lumbar spinal cord (L-SC) by computer modeling; and to apply this montage to measure the effect on LMN excitability and somatosensory evoked potentials (SSEP). Methods A human volume conductor model was obtained from an available database. The E-field distribution was calculated considering three different electrode settings aiming at maximizing the field at L-SC and right dorsal root ganglia (DRG). The best electrode setting was then selected and applied in a blind crossover pseudo-randomized study including 14 subjects. tsDCS was delivered for 15 min (cathodal vs. sham) over L2 vertebra level (4 mA, 144 mC/cm2), and its effect on F-waves, H-reflex (including homosynaptic depression, HD) and SSEPs was investigated in the lower limbs. Results All simulated montages showed higher current density and E-field magnitudes between the electrodes (>0.15 V/m), with a major longitudinal component and with rostral-caudal direction. The induced E-field involved the sensory ganglia and was maximum in the right T8-left L2 montage, which was the one selected for the experimental protocol. We disclosed a statistically significant increase of the H-reflex amplitude at 0.1 Hz, after cathodal tsDCS (c-tsDCS) on both sides. No other significant change was observed. Discussion Our results can suggest the c-tsDCS applied to the L-SC and DRG can modulate synaptic efficiency increasing lower motor neurons response to Ia fibers excitation. The possible implications of our findings for treating clinical conditions will be addressed in future studies.
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Affiliation(s)
- Mariana Pereira
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Sofia Rita Fernandes
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal,Instituto de Biofísica e Engenharia Biomédica, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
| | - Pedro Cavaleiro Miranda
- Instituto de Biofísica e Engenharia Biomédica, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
| | - Mamede de Carvalho
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal,Departamento de Neurociências e Saúde Mental, Hospital de Santa Maria - Centro Hospitalar Lisboa Norte, Lisboa, Portugal,*Correspondence: Mamede de Carvalho,
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Kobayashi RO, Gogeascoechea A, Tomy LJ, Asseldonk EV, Sartori M. Neural data-driven model of spinal excitability changes induced by transcutaneous electrical stimulation in spinal cord injury subjects. IEEE Int Conf Rehabil Robot 2022; 2022:1-6. [PMID: 36176142 DOI: 10.1109/icorr55369.2022.9896517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The efficacy of trans-spinal direct current stimulation (tsDCS) as neurorehabilitation technology remains sub-optimal, partly due to the variability introduced by subject-specific neurophysiological features and stimulation conditions (e.g. electrode placement, stimulating amplitude, polarity, etc.) Hence, current therapies apply tsDCS in an open-loop fashion, resulting in a lack of standardized protocols for controlling elicited neuronal adaptations in closed-loop. Through the combination of high-density electromyogram (HD-EMG) decomposition, biophysical neuronal modelling and metaheuristic optimization, this work presents a novel neural data-driven framework for estimating subject-specific features and quantifying acute neuronal adaptations elicited by tsDCS on incomplete spinal cord injury subjects. This approach consists of calibrating the anatomical parameters (e.g. soma diameter) of in silico $\alpha-$motoneuron (MN) models for firing similarly to in vivo MNs decoded from HD-EMG. Assuming that cathodal-tsDCS elicits excitability changes in the MN pool, while preserving their anatomical parameters, optimization of an excitability gain common to the entire pool was performed to minimize discrepancies in firing rate and recruitment time between in vivo and in silico MNs after cathodal-tsDCS. This quantification of excitability changes on MN models calibrated in a person specific way enables closing the loop with neuro-modulation devices to tailor neurorehabilitation therapies. Clinical Relevance - This framework addresses a key limitation in non-invasive neuro-modulative technologies via a novel model-assisted framework that enables quantifying acute excitability changes induced on a person-specific in silico MN pool calibrated using in vivo neural data. This will enable the development of advanced controllers for modulating targeted neuronal adaptations in closed-loop.
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Lin JT, Hsu CJ, Dee W, Chen D, Rymer WZ, Wu M. Anodal transcutaneous DC stimulation enhances learning of dynamic balance control during walking in humans with spinal cord injury. Exp Brain Res 2022; 240:1943-1955. [PMID: 35622090 PMCID: PMC9297533 DOI: 10.1007/s00221-022-06388-6] [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: 12/01/2021] [Accepted: 05/12/2022] [Indexed: 11/29/2022]
Abstract
Deficits in locomotor function, including impairments in walking speed and balance, are major problems for many individuals with incomplete spinal cord injury (iSCI). However, it remains unclear which type of training paradigms are more effective in improving balance, particularly dynamic balance, in individuals with iSCI. The purpose of this study was to determine whether anodal transcutaneous spinal direct current stimulation (tsDCS) can facilitate learning of balance control during walking in individuals with iSCI. Fifteen individuals with iSCI participated in this study and were tested in two sessions (i.e., tsDCS and sham conditions). Each session consisted of 1 min of treadmill walking without stimulation or perturbation (baseline), 10 min of walking with either anodal tsDCS or sham stimulation, paired with bilateral pelvis perturbation (adaptation), and finally 2 min of walking without stimulation and perturbation (post-adaptation). The outcome measures were the dynamic balance, assessed using the minimal margin of stability (MoS), and electromyography of leg muscles. Participants demonstrated a smaller MoS during the late adaptation period for the anodal tsDCS condition compared to sham (p = 0.041), and this MoS intended to retain during the early post-adaptation period (p = 0.05). In addition, muscle activity of hip abductors was greater for the anodal tsDCS condition compared to sham during the late adaptation period and post-adaptation period (p < 0.05). Results from this study suggest that anodal tsDCS may modulate motor adaptation to pelvis perturbation and facilitate learning of dynamic balance control in individuals with iSCI.
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Affiliation(s)
- Jui-Te Lin
- Legs and Walking Lab, Shirley Ryan AbilityLab, 355 E. Erie Street, Chicago, IL, 60611, USA.,Seton Hall University, South Orange, NJ, USA
| | - Chao-Jung Hsu
- Legs and Walking Lab, Shirley Ryan AbilityLab, 355 E. Erie Street, Chicago, IL, 60611, USA
| | - Weena Dee
- Legs and Walking Lab, Shirley Ryan AbilityLab, 355 E. Erie Street, Chicago, IL, 60611, USA
| | - David Chen
- Legs and Walking Lab, Shirley Ryan AbilityLab, 355 E. Erie Street, Chicago, IL, 60611, USA
| | - W Zev Rymer
- Legs and Walking Lab, Shirley Ryan AbilityLab, 355 E. Erie Street, Chicago, IL, 60611, USA.,Department of Physical Medicine and Rehabilitation, Northwestern University, Chicago, IL, USA
| | - Ming Wu
- Legs and Walking Lab, Shirley Ryan AbilityLab, 355 E. Erie Street, Chicago, IL, 60611, USA. .,Department of Physical Medicine and Rehabilitation, Northwestern University, Chicago, IL, USA. .,Department of Biomedical Engineering, University of Illinois at Chicago, Chicago, IL, USA.
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Song W, Martin JH. Trans-Spinal Direct Current Stimulation Targets Ca 2+ Channels to Induce Persistent Motor Unit Responses. Front Neurosci 2022; 16:856948. [PMID: 35546896 PMCID: PMC9081846 DOI: 10.3389/fnins.2022.856948] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 03/04/2022] [Indexed: 01/13/2023] Open
Abstract
Trans-spinal direct current stimulation (tsDCS) is a neuromodulatory approach to augment spinal cord activity to improve function after neurological disease and injury. Little is known about the mechanisms underlying tsDCS actions on the motor system. The purpose of this study is to determine the role for a persistent inward current (PIC)-like response in motoneurons in mediating tsDCS actions. We recorded single motor units from the extensor and flexor carpi radialis muscles in healthy sedated rats and measured unit activity changes produced by cervical enlargement cathodal and anodal tsDCS (c-tsDCS; a-tsDCS). Both c-tsDCS and a-tsDCS immediately increased spontaneous motor unit firing during stimulation. After c-tsDCS was stopped, spontaneous firing persisted for a substantial period (165 ± 5s), yet after a-tsDCS activity shortly returned to baseline (27 ± 7s). Administration of the L-type calcium channel blocker Nimodipine reduced spontaneous motor unit firing during c-tsDCS and blocked the persistent response. By contrast, Nimodipine did not change unit firing during a-tsDCS but the short persistent response was blocked. Computer simulation using a two-compartment neuronal model replicated the main experimental observations: larger and more persistent responses during and after c-tsDCS than a-tsDCS. Using reduced Ca2+ conductance to model Nimodipine action, a reduced response during c-tsDCS and elimination of the persistent response was observed. Our experimental findings, supported by computer simulation, show that c-tsDCS can target Ca2+ conductances to augment motoneuron activity. As tsDCS is well-tolerated in humans, this knowledge informs therapeutic treatment strategies to achieve rehabilitation goals after injury; in particular, to increase muscle force.
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Affiliation(s)
- Weiguo Song
- 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.,Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, United States
| | - 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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11
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Fava de Lima F, Silva CR, Kohn AF. Transcutaneous spinal direct current stimulation (tsDCS) does not affect postural sway of young and healthy subjects during quiet upright standing. PLoS One 2022; 17:e0267718. [PMID: 35482798 PMCID: PMC9049532 DOI: 10.1371/journal.pone.0267718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 04/13/2022] [Indexed: 12/02/2022] Open
Abstract
Transcutaneous spinal direct current stimulation (tsDCS) is an effective non-invasive spinal cord electrical stimulation technique to induce neuromodulation of local and distal neural circuits of the central nervous system (CNS). Applied to the spinal cord lumbosacral region, tsDCS changes electrophysiological responses of the motor, proprioceptive and nociceptive pathways, alters the performance of some lower limb motor tasks and can even modulate the behavior of supramedullary neuronal networks. In this study an experimental protocol was conducted to verify if tsDCS (5 mA, 20 minutes) of two different polarizations, applied over the lumbosacral region (tenth thoracic vertebrae (T10)), can induce changes in postural sway oscillations of young healthy individuals during quiet standing. A novel initialization of the electrical stimulation was developed to improve subject blinding to the different stimulus conditions including the sham trials. Measures of postural sway, both global and structural, were computed before, during and following the DC stimulation period. The results indicated that, for the adopted conditions, tsDCS did not induce statistically significant changes in postural sway of young healthy individuals during quiet standing.
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Affiliation(s)
- Felipe Fava de Lima
- Biomedical Engineering Laboratory, Escola Politécnica, University of São Paulo, São Paulo, Brazil
- * E-mail:
| | - Cristiano Rocha Silva
- Biomedical Engineering Laboratory, Escola Politécnica, University of São Paulo, São Paulo, Brazil
| | - Andre Fabio Kohn
- Biomedical Engineering Laboratory, Escola Politécnica, University of São Paulo, São Paulo, Brazil
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12
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Hawkins KA, DeMark LA, Vistamehr A, Snyder HJ, Conroy C, Wauneka C, Tonuzi G, Fuller DD, Clark DJ, Fox EJ. Feasibility of transcutaneous spinal direct current stimulation combined with locomotor training after spinal cord injury. Spinal Cord 2022; 60:971-977. [PMID: 35477745 PMCID: PMC9606142 DOI: 10.1038/s41393-022-00801-1] [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: 11/16/2021] [Revised: 03/30/2022] [Accepted: 04/01/2022] [Indexed: 11/16/2022]
Abstract
Study Design: Feasibility study, consisting of random-order, cross-over study of a single intervention session, followed by a parallel-arm study of 16 sessions Objectives: To investigate the feasibility of a novel combinatorial approach with simultaneous delivery of transcutaneous spinal direct current stimulation (tsDCS) and locomotor training (tsDCS+LT) after spinal cord injury, compared to sham stimulation and locomotor training (sham+LT), and examine preliminary effects on walking function. Setting: Clinical research center in the southeastern United States Methods: Eight individuals with chronic incomplete spinal cord injury (ISCI) completed the two-part protocol. Feasibility was assessed based on safety (adverse responses), tolerability (pain, spasticity, skin integrity), and protocol achievement (session duration, intensity). Walking function was assessed with the 10-meter and 6-minute walk tests. Results: There were no major adverse responses. Minimal reports of skin irritation and musculoskeletal pain were consistent between groups. Average training peak heart rate as percent of maximum (mean(SD); tsDCS+LT: 66(4)%, sham+LT: 69(10)%) and Borg ratings of perceived exertion (tsDCS+LT: 17.5(1.2), sham+LT: 14.4(1.8)) indicate both groups trained at high intensities. Walking speed gains exceeded the minimal clinically important difference (MCID) in three of four who received tsDCS+LT (0.18(0.29) m/s) and one of four in sham+LT (−0.05(0.23) m/s). Gains in walking endurance exceeded the MCID in one of four in each group (tsDCS+LT: 36.4(69.0) m, sham+LT: 4.9(56.9) m). Conclusions: Combinatorial tsDCS and locomotor training is safe and feasible for individuals with chronic ISCI, even those with considerable walking impairment. Study outcomes support the need to investigate the efficacy of this approach.
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Affiliation(s)
- Kelly A Hawkins
- Department of Physical Therapy, University of Florida, Gainesville, FL, USA
| | | | | | | | | | | | | | - David D Fuller
- Department of Physical Therapy, University of Florida, Gainesville, FL, USA
| | - David J Clark
- Brain Rehabilitation Research Center of Excellence, North Florida/South Georgia Veterans Health System, Gainesville, FL, USA.,Department of Aging and Geriatric Research, University of Florida, Gainesville, FL, USA
| | - Emily J Fox
- Department of Physical Therapy, University of Florida, Gainesville, FL, USA. .,Brooks Rehabilitation, Jacksonville, FL, USA.
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13
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Rahman MA, Tharu NS, Gustin SM, Zheng YP, Alam M. Trans-Spinal Electrical Stimulation Therapy for Functional Rehabilitation after Spinal Cord Injury: Review. J Clin Med 2022; 11:jcm11061550. [PMID: 35329875 PMCID: PMC8954138 DOI: 10.3390/jcm11061550] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 03/04/2022] [Accepted: 03/09/2022] [Indexed: 01/25/2023] Open
Abstract
Spinal cord injury (SCI) is one of the most debilitating injuries in the world. Complications after SCI, such as respiratory issues, bowel/bladder incontinency, pressure ulcers, autonomic dysreflexia, spasticity, pain, etc., lead to immense suffering, a remarkable reduction in life expectancy, and even premature death. Traditional rehabilitations for people with SCI are often insignificant or ineffective due to the severity and complexity of the injury. However, the recent development of noninvasive electrical neuromodulation treatments to the spinal cord have shed a ray of hope for these individuals to regain some of their lost functions, a reduction in secondary complications, and an improvement in their life quality. For this review, 250 articles were screened and about 150 were included to summarize the two most promising noninvasive spinal cord electrical stimulation methods of SCI rehabilitation treatment, namely, trans-spinal direct current stimulation (tsDCS) and trans-spinal pulsed current stimulation (tsPCS). Both treatments have demonstrated good success in not only improving the sensorimotor function, but also autonomic functions. Due to the noninvasive nature and lower costs of these treatments, in the coming years, we expect these treatments to be integrated into regular rehabilitation therapies worldwide.
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Affiliation(s)
- Md. Akhlasur Rahman
- Department of Biomedical Engineering, The Hong Kong Polytechnic University, Hong Kong, China; (M.A.R.); (N.S.T.); (Y.-P.Z.)
- Centre for the Rehabilitation of the Paralysed (CRP), Savar Union 1343, Bangladesh
| | - Niraj Singh Tharu
- Department of Biomedical Engineering, The Hong Kong Polytechnic University, Hong Kong, China; (M.A.R.); (N.S.T.); (Y.-P.Z.)
| | - Sylvia M. Gustin
- NeuroRecovery Research Hub, School of Psychology, University of New South Wales, Sydney, NSW 2052, Australia;
- Centre for Pain IMPACT, Neuroscience Research Australia, Sydney, NSW 2031, Australia
| | - Yong-Ping Zheng
- Department of Biomedical Engineering, The Hong Kong Polytechnic University, Hong Kong, China; (M.A.R.); (N.S.T.); (Y.-P.Z.)
| | - Monzurul Alam
- Department of Biomedical Engineering, The Hong Kong Polytechnic University, Hong Kong, China; (M.A.R.); (N.S.T.); (Y.-P.Z.)
- NeuroRecovery Research Hub, School of Psychology, University of New South Wales, Sydney, NSW 2052, Australia;
- Centre for Pain IMPACT, Neuroscience Research Australia, Sydney, NSW 2031, Australia
- Correspondence: ; Tel.: +852-6213-5054
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14
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Clark DJ, Hawkins KA, Winesett SP, Cox BA, Pesquera S, Miles JW, Fuller DD, Fox EJ. Enhancing Locomotor Learning With Transcutaneous Spinal Electrical Stimulation and Somatosensory Augmentation: A Pilot Randomized Controlled Trial in Older Adults. Front Aging Neurosci 2022; 14:837467. [PMID: 35309891 PMCID: PMC8924500 DOI: 10.3389/fnagi.2022.837467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 02/10/2022] [Indexed: 11/18/2022] Open
Abstract
This study investigated locomotor learning of a complex terrain walking task in older adults, when combined with two adjuvant interventions: transcutaneous spinal direct current stimulation (tsDCS) to increase lumbar spinal cord excitability, and textured shoe insoles to increase somatosensory feedback to the spinal cord. The spinal cord has a crucial contribution to control of walking, and is a novel therapeutic target for rehabilitation of older adults. The complex terrain task involved walking a 10-meter course consisting of nine obstacles and three sections of compliant (soft) walking surface. Twenty-three participants were randomly assigned to one of the following groups: sham tsDCS and smooth insoles (sham/smooth; control group), sham tsDCS and textured insoles (sham/textured), active tsDCS and smooth insoles (active/smooth), and active tsDCS and textured insoles (active/textured). The first objective was to assess the feasibility, tolerability, and safety of the interventions. The second objective was to assess preliminary efficacy for increasing locomotor learning, as defined by retention of gains in walking speed between a baseline visit of task practice, and a subsequent follow-up visit. Variability of the center of mass while walking over the course was also evaluated. The change in executive control of walking (prefrontal cortical activity) between the baseline and follow-up visits was measured with functional near infrared spectroscopy. The study results demonstrated feasibility based on enrollment and retention of participants, tolerability based on self-report, and safety based on absence of adverse events. Preliminary efficacy was supported based on trends showing larger gains in walking speed and more pronounced reductions in mediolateral center of mass variability at the follow-up visit in the groups randomized to active tsDCS or textured insoles. These data justify future larger studies to further assess dosing and efficacy of these intervention approaches. In conclusion, rehabilitation interventions that target spinal control of walking present a potential opportunity for enhancing walking function in older adults.
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Affiliation(s)
- David J. Clark
- Brain Rehabilitation Research Center, Malcom Randall VA Medical Center, Gainesville, FL, United States
- Department of Aging and Geriatric Research, University of Florida, Gainesville, FL, United States
- *Correspondence: David J. Clark,
| | - Kelly A. Hawkins
- Brain Rehabilitation Research Center, Malcom Randall VA Medical Center, Gainesville, FL, United States
- Department of Physical Therapy, University of Florida, Gainesville, FL, United States
| | - Steven P. Winesett
- Brain Rehabilitation Research Center, Malcom Randall VA Medical Center, Gainesville, FL, United States
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, United States
| | - Brigette A. Cox
- Brain Rehabilitation Research Center, Malcom Randall VA Medical Center, Gainesville, FL, United States
| | - Sarah Pesquera
- Brain Rehabilitation Research Center, Malcom Randall VA Medical Center, Gainesville, FL, United States
| | - Jon W. Miles
- Brain Rehabilitation Research Center, Malcom Randall VA Medical Center, Gainesville, FL, United States
| | - David D. Fuller
- Department of Physical Therapy, University of Florida, Gainesville, FL, United States
| | - Emily J. Fox
- Department of Physical Therapy, University of Florida, Gainesville, FL, United States
- Brooks Rehabilitation, Jacksonville, FL, United States
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15
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Effects of paired stimulation with specific waveforms on cortical and spinal plasticity in subjects with a chronic spinal cord injury. J Formos Med Assoc 2022; 121:2044-2056. [DOI: 10.1016/j.jfma.2022.02.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 12/13/2021] [Accepted: 02/17/2022] [Indexed: 12/16/2022] Open
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16
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Carrera RM, Omofuma I, Yasin B, Agrawal SK. The Effect of Transcutaneous Spinal Cord Stimulation on Standing Postural Control in Healthy Adults. IEEE Robot Autom Lett 2022. [DOI: 10.1109/lra.2022.3185370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Robert M. Carrera
- Department of Biomedical Engineering, Columbia University,, New York, NY, USA
| | - Isirame Omofuma
- Department of Biomedical Engineering, Columbia University,, New York, NY, USA
| | - Bushra Yasin
- Mechanical Engineering Department, Columbia University, New York, NY, USA
| | - Sunil K. Agrawal
- Departments of Mechanical Engineering and Rehabilitation and, Regenerative Medicine, New York, NY, USA
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17
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Guidetti M, Ferrucci R, Vergari M, Aglieco G, Naci A, Versace S, Pacheco-Barrios K, Giannoni-Luza S, Barbieri S, Priori A, Bocci T. Effects of Transcutaneous Spinal Direct Current Stimulation (tsDCS) in Patients With Chronic Pain: A Clinical and Neurophysiological Study. Front Neurol 2021; 12:695910. [PMID: 34552550 PMCID: PMC8450534 DOI: 10.3389/fneur.2021.695910] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 07/30/2021] [Indexed: 12/27/2022] Open
Abstract
Background and Aims: Chronic pain is a complex clinical condition, often devastating for patients and unmanageable with pharmacological treatments. Converging evidence suggests that transcutaneous spinal Direct Current Stimulation (tsDCS) might represent a complementary therapy in managing chronic pain. In this randomized, double-blind and sham-controlled crossover study, we assessed tsDCS effects in chronic pain patients. Methods: Sixteen patients (aged 65.06 ± 16.16 years, eight women) with chronic pain of different etiology underwent sham and anodal tsDCS (anode over the tenth thoracic vertebra, cathode over the somatosensory cortical area: 2.5 mA, 20 min, 5 days for 1 week). As outcomes, we considered the Visual Analog Scale (VAS), the Neuropathic Pain Symptom Inventory (NPSI), and the components of the lower limb flexion reflex (LLFR), i.e., RIII threshold, RII latency and area, RIII latency and area, and flexion reflex (FR) total area. Assessments were conducted before (T0), immediately at the end of the treatment (T1), after 1 week (T2) and 1 month (T3). Results: Compared to sham, anodal tsDCS reduced RIII area at T2 (p = 0.0043) and T3 (p = 0.0012); similarly, FR total area was reduced at T3 (p = 0.03). Clinically, anodal tsDCS dampened VAS at T3 (p = 0.015), and NPSI scores at T1 (p = 0.0012), and T3 (p = 0.0015), whereas sham condition left them unchanged. Changes in VAS and NPSI scores linearly correlated with the reduction in LLFR areas (p = 0.0004). Conclusions: Our findings suggest that tsDCS could modulate nociceptive processing and pain perception in chronic pain syndromes.
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Affiliation(s)
- Matteo Guidetti
- "Aldo Ravelli" Center for Neurotechnology and Experimental Brain Therapeutics, Department of Health Sciences, University of Milan, Milan, Italy.,Department of Electronics, Information and Bioengineering, Politecnico di Milano, Milan, Italy
| | - Roberta Ferrucci
- "Aldo Ravelli" Center for Neurotechnology and Experimental Brain Therapeutics, Department of Health Sciences, University of Milan, Milan, Italy.,Azienda Socio-Sanitaria Territoriale-Santi Paolo e Carlo University Hospital, Milan, Italy
| | - Maurizio Vergari
- Neurophysiology Unit, Foundation Istituto di Ricerca e Cura a Carattere Scientifico Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Giada Aglieco
- Neurophysiology Unit, Foundation Istituto di Ricerca e Cura a Carattere Scientifico Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Anisa Naci
- Neurophysiology Unit, Foundation Istituto di Ricerca e Cura a Carattere Scientifico Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Sara Versace
- Neurophysiology Unit, Foundation Istituto di Ricerca e Cura a Carattere Scientifico Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Kevin Pacheco-Barrios
- Neuromodulation Center, Spaulding Rehabilitation Hospital, Boston, MA, United States.,Center for Clinical Research Learning, Massachusetts General Hospital, Boston, MA, United States.,Unidad de Investigación para la Generación y Síntesis de Evidencias en Salud, Universidad San Ignacio de Loyola, Lima, Peru
| | - Stefano Giannoni-Luza
- Neuromodulation Center, Spaulding Rehabilitation Hospital, Boston, MA, United States.,Center for Clinical Research Learning, Massachusetts General Hospital, Boston, MA, United States
| | - Sergio Barbieri
- Neurophysiology Unit, Foundation Istituto di Ricerca e Cura a Carattere Scientifico Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Alberto Priori
- "Aldo Ravelli" Center for Neurotechnology and Experimental Brain Therapeutics, Department of Health Sciences, University of Milan, Milan, Italy.,Azienda Socio-Sanitaria Territoriale-Santi Paolo e Carlo University Hospital, Milan, Italy
| | - Tommaso Bocci
- "Aldo Ravelli" Center for Neurotechnology and Experimental Brain Therapeutics, Department of Health Sciences, University of Milan, Milan, Italy.,Azienda Socio-Sanitaria Territoriale-Santi Paolo e Carlo University Hospital, Milan, Italy
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18
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Modulation of torque evoked by wide-pulse, high-frequency neuromuscular electrical stimulation and the potential implications for rehabilitation and training. Sci Rep 2021; 11:6399. [PMID: 33737664 PMCID: PMC7973712 DOI: 10.1038/s41598-021-85645-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 03/01/2021] [Indexed: 11/09/2022] Open
Abstract
The effectiveness of neuromuscular electrical stimulation (NMES) for rehabilitation is proportional to the evoked torque. The progressive increase in torque (extra torque) that may develop in response to low intensity wide-pulse high-frequency (WPHF) NMES holds great promise for rehabilitation as it overcomes the main limitation of NMES, namely discomfort. WPHF NMES extra torque is thought to result from reflexively recruited motor units at the spinal level. However, whether WPHF NMES evoked force can be modulated is unknown. Therefore, we examined the effect of two interventions known to change the state of spinal circuitry in opposite ways on evoked torque and motor unit recruitment by WPHF NMES. The interventions were high-frequency transcutaneous electrical nerve stimulation (TENS) and anodal transcutaneous spinal direct current stimulation (tsDCS). We show that TENS performed before a bout of WPHF NMES results in lower evoked torque (median change in torque time-integral: - 56%) indicating that WPHF NMES-evoked torque might be modulated. In contrast, the anodal tsDCS protocol used had no effect on any measured parameter. Our results demonstrate that WPHF NMES extra torque can be modulated and although the TENS intervention blunted extra torque production, the finding that central contribution to WPHF NMES-evoked torques can be modulated opens new avenues for designing interventions to enhance WPHF NMES.
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19
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Ciccone AB, Fry AC, Emerson DM, Gallagher PM, Herda TJ, Weir JP. Effects of Transspinal Direct Current Stimulation on Cycling Perception of Effort and Time to Exhaustion. J Strength Cond Res 2021; 35:347-352. [PMID: 33306592 DOI: 10.1519/jsc.0000000000003876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
ABSTRACT Ciccone, AB, Fry, AC, Emerson, DM, Gallagher, PM, Herda, TJ, and Weir, JP. Effects of transspinal direct current stimulation on cycling perception of effort and time to exhaustion. J Strength Cond Res 35(2): 347-352, 2021-In the past decade, researchers have investigated the efficacy of transspinal direct current stimulation (tsDCS) on the central nervous system and afferent neuron function in humans. Recently, data have suggested it may be possible for such tsDCS-induced changes in neuromuscular function to enhance performance. This study used noninvasive thoracic spine tsDCS to determine if cycling performance and perception of effort could be modulated by tsDCS. In 3 different stimulation conditions, anodal, cathodal, and sham, subjects cycled at 80% of their maximal aerobic capacity until exhaustion and reported their rating of perceived exertion (RPE) every minute. From this period, we compared the RPE responses over the first 3 minutes and time to exhaustion. There was no significant difference in time to exhaustion between anodal (408 ± 121 seconds), cathodal (413 ± 168 seconds), and sham (440 ± 189 seconds) conditions (p = 0.58). There was no significant difference in RPE from minutes 1-3 (collapsed across time) between anodal (12.9 ± 2.4 arbitrary units (AUs)), cathodal (13.3 ± 2.2 AUs), and sham (12.9 ± 2.1 AUs) conditions (p = 0.51). These data suggest tsDCS condition did not influence cycling performance or perception of effort during high-intensity cycling. Therefore, thoracic spine and lower abdominal montage delivering a current density of 0.071 mA·cm-2 for 20 minutes likely does not substantially improve high-intensity cycling work capacity. Therefore, more research is needed to investigate the efficacy of tsDCS and which stimulation methods may and may not enhance human performance.
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Affiliation(s)
- Anthony B Ciccone
- Department of Exercise Science and Outdoor Recreation, Utah Valley University, Orem, Utah; and
| | - Andrew C Fry
- Osness Human Performance Laboratories, Department of Health, Sport, and Exercise Sciences, University of Kansas, Lawrence, Kansas
| | - Dawn M Emerson
- Osness Human Performance Laboratories, Department of Health, Sport, and Exercise Sciences, University of Kansas, Lawrence, Kansas
| | - Philip M Gallagher
- Osness Human Performance Laboratories, Department of Health, Sport, and Exercise Sciences, University of Kansas, Lawrence, Kansas
| | - Trent J Herda
- Osness Human Performance Laboratories, Department of Health, Sport, and Exercise Sciences, University of Kansas, Lawrence, Kansas
| | - Joseph P Weir
- Osness Human Performance Laboratories, Department of Health, Sport, and Exercise Sciences, University of Kansas, Lawrence, Kansas
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20
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Bączyk M, Krutki P, Zytnicki D. Is there hope that transpinal direct current stimulation corrects motoneuron excitability and provides neuroprotection in amyotrophic lateral sclerosis? Physiol Rep 2021; 9:e14706. [PMID: 33463907 PMCID: PMC7814489 DOI: 10.14814/phy2.14706] [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: 09/24/2020] [Revised: 12/06/2020] [Accepted: 12/08/2020] [Indexed: 12/14/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease of largely unknown pathophysiology, characterized by the progressive loss of motoneurons (MNs). We review data showing that in presymptomatic ALS mice, MNs display reduced intrinsic excitability and impaired level of excitatory inputs. The loss of repetitive firing specifically affects the large MNs innervating fast contracting muscle fibers, which are the most vulnerable MNs in ALS. Interventions that aimed at restoring either the intrinsic excitability or the synaptic excitation result in a decrease of disease markers in MNs and delayed neuromuscular junction denervation. We then focus on trans‐spinal direct current stimulation (tsDCS), a noninvasive tool, since it modulates the activity of spinal neurons and networks. Effects of tsDCS depend on the polarity of applied current. Recent work shows that anodal tsDCS induces long‐lasting enhancement of MN excitability and synaptic excitation of spinal MNs. Moreover, we show preliminary results indicating that anodal tsDCS enhances the excitatory synaptic inputs to MNs in ALS mice. In conclusion, we suggest that chronic application of anodal tsDCS might be useful as a complementary method in the management of ALS patients.
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Affiliation(s)
- Marcin Bączyk
- Department of Neurobiology, Poznan University of Physical Education, Poznań, Poland
| | - Piotr Krutki
- Department of Neurobiology, Poznan University of Physical Education, Poznań, Poland
| | - Daniel Zytnicki
- Université de Paris, Centre National de la Recherche Scientifique (CNRS), Saints-Pères Paris Institute for the Neurosciences (SPPIN), Paris, France
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21
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Transcutaneous spinal direct current stimulation shows no effect on paired stimulation suppression of the somatosensory cortex. Sci Rep 2020; 10:22010. [PMID: 33319846 PMCID: PMC7738485 DOI: 10.1038/s41598-020-79131-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 12/03/2020] [Indexed: 11/08/2022] Open
Abstract
Transcutaneous spinal direct current stimulation (tsDCS) is a safe and convenient method of neuromodulation. It has been proven to alter sensory processing at cervicomedullary level by amplitude changes of the P30 response of tibial nerve somatosensory evoked potentials (TN SEPs). With knowledge that tsDCS affects cortical circuits, we hypothesized that tsDCS may also affect intracortical excitability of the somatosensory cortex assessed by paired stimulation suppression (PSS). Fourteen healthy men were included in this prospective, single-blinded, placebo-controlled crossover study. Single (SS) and paired stimulation (PS) TN SEPs were recorded over the scalp before, immediately as well as 30 and 60 min after applying 15 min of tsDCS over the twelfth thoracic vertebra. Each volunteer underwent three independent and randomized sessions of either cathodal, anodal or sham stimulation. tsDCS showed no effect on peak-to-peak amplitudes or latencies of cortical P40-N50 response after SS. Furthermore, tsDCS failed to induce significant changes on amplitude ratios of PSS, thus showing no impact on intracortical excitability of the somatosensory cortex in healthy subjects. Further research is required to reveal the different mechanisms and to strengthen clinical use of this promising technique.
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22
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Gogeascoechea A, Kuck A, van Asseldonk E, Negro F, Buitenweg JR, Yavuz US, Sartori M. Interfacing With Alpha Motor Neurons in Spinal Cord Injury Patients Receiving Trans-spinal Electrical Stimulation. Front Neurol 2020; 11:493. [PMID: 32582012 PMCID: PMC7296155 DOI: 10.3389/fneur.2020.00493] [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: 01/20/2020] [Accepted: 05/05/2020] [Indexed: 12/22/2022] Open
Abstract
Trans-spinal direct current stimulation (tsDCS) provides a non-invasive, clinically viable approach to potentially restore physiological neuromuscular function after neurological impairment, e.g., spinal cord injury (SCI). Use of tsDCS has been hampered by the inability of delivering stimulation patterns based on the activity of neural targets responsible to motor function, i.e., α-motor neurons (α-MNs). State of the art modeling and experimental techniques do not provide information about how individual α-MNs respond to electrical fields. This is a major element hindering the development of neuro-modulative technologies highly tailored to an individual patient. For the first time, we propose the use of a signal-based approach to infer tsDCS effects on large α-MNs pools in four incomplete SCI individuals. We employ leg muscles spatial sampling and deconvolution of high-density fiber electrical activity to decode accurate α-MNs discharges across multiple lumbosacral segments during isometric plantar flexion sub-maximal contractions. This is done before, immediately after and 30 min after sub-threshold cathodal stimulation. We deliver sham tsDCS as a control measure. First, we propose a new algorithm for removing compromised information from decomposed α-MNs spike trains, thereby enabling robust decomposition and frequency-domain analysis. Second, we propose the analysis of α-MNs spike trains coherence (i.e., frequency-domain) as an indicator of spinal response to tsDCS. Results showed that α-MNs spike trains coherence analysis sensibly varied across stimulation phases. Coherence analyses results suggested that the common synaptic input to α-MNs pools decreased immediately after cathodal tsDCS with a persistent effect after 30 min. Our proposed non-invasive decoding of individual α-MNs behavior may open up new avenues for the design of real-time closed-loop control applications including both transcutaneous and epidural spinal electrical stimulation where stimulation parameters are adjusted on-the-fly.
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Affiliation(s)
- Antonio Gogeascoechea
- Department of Biomechanical Engineering, University of Twente, Enschede, Netherlands
| | - Alexander Kuck
- Department of Biomechanical Engineering, University of Twente, Enschede, Netherlands
| | - Edwin van Asseldonk
- Department of Biomechanical Engineering, University of Twente, Enschede, Netherlands
| | - Francesco Negro
- Department of Clinical and Experimental Sciences, Università degli Studi di Brescia, Brescia, Italy
| | - Jan R Buitenweg
- Biomedical Signals and Systems Group, University of Twente, Enschede, Netherlands
| | - Utku S Yavuz
- Biomedical Signals and Systems Group, University of Twente, Enschede, Netherlands
| | - Massimo Sartori
- Department of Biomechanical Engineering, University of Twente, Enschede, Netherlands
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Awosika OO, Matthews S, Staggs EJ, Boyne P, Song X, Rizik BA, Sucharew HJ, Zhang C, Mungcal G, Moudgal R, Bhattacharya A, Dunning K, Woo D, Kissela BM. Backward locomotor treadmill training combined with transcutaneous spinal direct current stimulation in stroke: a randomized pilot feasibility and safety study. Brain Commun 2020; 2:fcaa045. [PMID: 32954299 PMCID: PMC7425394 DOI: 10.1093/braincomms/fcaa045] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 02/13/2020] [Accepted: 02/19/2020] [Indexed: 11/17/2022] Open
Abstract
Walking impairment impacts nearly 66% of stroke survivors and is a rising cause of morbidity worldwide. Despite conventional post-stroke rehabilitative care, the majority of stroke survivors experience continued limitations in their walking speed, temporospatial dynamics and walking capacity. Hence, novel and comprehensive approaches are needed to improve the trajectory of walking recovery in stroke survivors. Herein, we test the safety, feasibility and preliminary efficacy of two approaches for post-stroke walking recovery: backward locomotor treadmill training and transcutaneous spinal direct current stimulation. In this double-blinded study, 30 chronic stroke survivors (>6 months post-stroke) with mild-severe residual walking impairment underwent six 30-min sessions (three sessions/week) of backward locomotor treadmill training, with concurrent anodal (N = 19) or sham transcutaneous spinal direct current stimulation (N = 11) over the thoracolumbar spine, in a 2:1 stratified randomized fashion. The primary outcomes were: per cent participant completion, safety and tolerability of these two approaches. In addition, we collected data on training-related changes in overground walking speed, cadence, stride length (baseline, daily, 24-h post-intervention, 2 weeks post-intervention) and walking capacity (baseline, 24-h post-intervention, 2 weeks post-intervention), as secondary exploratory aims testing the preliminary efficacy of these interventions. Eighty-seven per cent (N = 26) of randomized participants completed the study protocol. The majority of the study attrition involved participants with severe baseline walking impairment. There were no serious adverse events in either the backward locomotor treadmill training or transcutaneous spinal direct current stimulation approaches. Also, both groups experienced a clinically meaningful improvement in walking speed immediately post-intervention that persisted at the 2-week follow-up. However, in contrast to our working hypothesis, anodal-transcutaneous spinal direct current stimulation did not enhance the degree of improvement in walking speed and capacity, relative to backward locomotor treadmill training + sham, in our sample. Backward locomotor treadmill training and transcutaneous spinal direct current stimulation are safe and feasible approaches for walking recovery in chronic stroke survivors. Definitive efficacy studies are needed to validate our findings on backward locomotor treadmill training-related changes in walking performance. The results raise interesting questions about mechanisms of locomotor learning in stroke, and well-powered transcutaneous spinal direct current stimulation dosing studies are needed to understand better its potential role as a neuromodulatory adjunct for walking rehabilitation.
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Affiliation(s)
- Oluwole O Awosika
- Department of Neurology and Rehabilitation Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Saira Matthews
- Department of Neurology and Rehabilitation Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Emily J Staggs
- Department of Neurology and Rehabilitation Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Pierce Boyne
- College of Allied Health and Sciences, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Xiao Song
- Department of Neurology and Rehabilitation Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Bridget A Rizik
- Department of Neurology and Rehabilitation Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Heidi J Sucharew
- Division of Biostatistics and Epidemiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
| | - Christina Zhang
- Department of Neurology and Rehabilitation Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Gabrielle Mungcal
- Department of Neurology and Rehabilitation Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Rohitha Moudgal
- Department of Neurology and Rehabilitation Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Amit Bhattacharya
- Biomechanics-Ergonomics Research Laboratories, Department of Environmental Health, University of Cincinnati Medical College, USA
| | - Kari Dunning
- College of Allied Health and Sciences, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Daniel Woo
- Department of Neurology and Rehabilitation Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Brett M Kissela
- Department of Neurology and Rehabilitation Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
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Paget-Blanc A, Chang JL, Saul M, Lin R, Ahmed Z, Volpe BT. Non-invasive treatment of patients with upper extremity spasticity following stroke using paired trans-spinal and peripheral direct current stimulation. Bioelectron Med 2020; 5:11. [PMID: 32232101 PMCID: PMC7098221 DOI: 10.1186/s42234-019-0028-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 06/24/2019] [Indexed: 12/17/2022] Open
Abstract
Background Muscle spasticity is a common impediment to motor recovery in patients with chronic stroke. Standard-of-care treatments such as botulinum toxin injections can temporarily relieve muscle stiffness and pain associated with spasticity, but often at the expense of increased muscle weakness. Recent preclinical investigations of a non-invasive treatment that pairs trans-spinal direct current stimulation and peripheral nerve direct current stimulation (tsDCS+pDCS) provided promising data for a novel approach based on bioelectronic medicine for the treatment of patients with post-stroke spasticity. Methods Twenty-six patients with upper limb hemiparesis and wrist spasticity at least 6 months after their initial stroke participated in this single-blind crossover design study to test whether tsDCS+pDCS reduces chronic upper-extremity spasticity. Subjects received five consecutive daily sessions (20 min of stimulation or sham) of anodal tsDCS+pDCS, separated by a one-week washout period. The sham condition always preceded the active condition. Clinical and objective measures of spasticity and motor function were collected before and after each condition, and for five weeks after the completion of the active intervention. Results Subjects treated with active tsDCS+pDCS demonstrated significant reductions in both Modified Tardieu Scale scores (summed across the upper limb, P < 0.05), and in objective torque measures (Nm) of the spastic catch response at the wrist flexor (P < 0.05), compared to the sham condition. Motor function also improved significantly (measured by the Fugl-Meyer and Wolf Motor Function Test; P < 0.05 for both tests) after active treatment. Conclusions tsDCS+pDCS intervention alone significantly reduced upper limb spasticity in participants with stroke. Decreased spasticity was persistent for five weeks after treatment, and was accompanied by improved motor function even though patients were unsupervised and there was no prescribed activity or training during that interval. Trial registration NCT03080454, March 15, 2017.
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Affiliation(s)
- Alexandra Paget-Blanc
- 1Feinstein Institute for Medical Research, Biomedical Science Division, Biomedical Sciences /Robot Lab, Laboratory of Clinical Neurorehabilitation Research, 350 Community Dr, Manhasset, NY 11030 USA
| | - Johanna L Chang
- 1Feinstein Institute for Medical Research, Biomedical Science Division, Biomedical Sciences /Robot Lab, Laboratory of Clinical Neurorehabilitation Research, 350 Community Dr, Manhasset, NY 11030 USA
| | - Maira Saul
- 1Feinstein Institute for Medical Research, Biomedical Science Division, Biomedical Sciences /Robot Lab, Laboratory of Clinical Neurorehabilitation Research, 350 Community Dr, Manhasset, NY 11030 USA
| | - Regina Lin
- BARC Global Central Laboratory, 5 Delaware Dr, Hyde Park, NY 11042 USA
| | - Zaghloul Ahmed
- College of Staten Island, Department of Physical Therapy, Center for Developmental Neuroscience, Staten Island, NY 10314 USA.,4Graduate Center, City University of New York, New York, NY USA
| | - Bruce T Volpe
- 1Feinstein Institute for Medical Research, Biomedical Science Division, Biomedical Sciences /Robot Lab, Laboratory of Clinical Neurorehabilitation Research, 350 Community Dr, Manhasset, NY 11030 USA
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Jadczak Ł, Wieczorek A, Grześkowiak M, Wieczorek J, Łochyński D. Jumping Height Does Not Increase in Well Trained Volleyball Players After Transcutaneous Spinal Direct Current Stimulation. Front Physiol 2019; 10:1479. [PMID: 31866875 PMCID: PMC6904281 DOI: 10.3389/fphys.2019.01479] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 11/18/2019] [Indexed: 01/21/2023] Open
Abstract
Transcutaneous spinal direct current stimulation (tsDCS) increases corticospinal and spinal reflex excitability, and may be a new tool for increasing muscle explosive performance in sports training. The aim of the study was to evaluate whether tsDCS can enhance jumping ability in trained humans practicing volleyball. Twenty eight participants completed the study, including 21 men and 7 women. We investigated the effects of a single 15-minute session of sham, anodal, and cathodal tsDCS over spine and shoulder on repeated counter movement jump (CMJ) and squat jump (SJ) performance at 0, 30 and 60 min post-stimulation. The order of SJs and CMJs sets in each session was randomized. Each SJ and CMJ set consisted of 3 jumps. The break between each attempt was 1 min and the interval between the sets was 3 min. Two-way repeated measures ANOVA did not show effect of time, nor stimulation method, nor stimulation method × time interactions on SJ (time: F(1.8,142.1) = 1.054; p = 0.346, stimulation: F(2,78) = 0.019; p = 0.981, stimulation × time: F(3.6,142.1) = 0.725; p = 0.564) or CMJ (time: F(1.8,140.9) = 2.092; p = 0.132, stimulation: F(2,78) = 0.005; p = 0.995, stimulation × time: F(3.6,140.9) = 0.517; p = 0.705) performance. Single session of tsDCS over spine and shoulder does not increase jumping height in well-trained volleyball players. This is an important finding for coaches and strength conditioning professionals for understanding the practical utility of tsDCS for enhancing muscular explosiveness.
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Affiliation(s)
- Łukasz Jadczak
- Department of Theory and Methodology of Team Sport Games, Poznań University of Physical Education, Poznań, Poland
| | - Andrzej Wieczorek
- Department of Theory and Methodology of Team Sport Games, Poznań University of Physical Education, Poznań, Poland
| | - Marcin Grześkowiak
- Department of Pulmonological and Rheumatological Rehabilitation, Poznań University of Physical Education, Poznań, Poland
| | - Jacek Wieczorek
- Department of Sport for Disabilities, Poznań University of Physical Education, Poznań, Poland
| | - Dawid Łochyński
- Department of Musculoskeletal Rehabilitation, Poznań University of Physical Education, Poznań, Poland
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26
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Morya E, Monte-Silva K, Bikson M, Esmaeilpour Z, Biazoli CE, Fonseca A, Bocci T, Farzan F, Chatterjee R, Hausdorff JM, da Silva Machado DG, Brunoni AR, Mezger E, Moscaleski LA, Pegado R, Sato JR, Caetano MS, Sá KN, Tanaka C, Li LM, Baptista AF, Okano AH. Beyond the target area: an integrative view of tDCS-induced motor cortex modulation in patients and athletes. J Neuroeng Rehabil 2019; 16:141. [PMID: 31730494 PMCID: PMC6858746 DOI: 10.1186/s12984-019-0581-1] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 08/19/2019] [Indexed: 02/07/2023] Open
Abstract
Transcranial Direct Current Stimulation (tDCS) is a non-invasive technique used to modulate neural tissue. Neuromodulation apparently improves cognitive functions in several neurologic diseases treatment and sports performance. In this study, we present a comprehensive, integrative review of tDCS for motor rehabilitation and motor learning in healthy individuals, athletes and multiple neurologic and neuropsychiatric conditions. We also report on neuromodulation mechanisms, main applications, current knowledge including areas such as language, embodied cognition, functional and social aspects, and future directions. We present the use and perspectives of new developments in tDCS technology, namely high-definition tDCS (HD-tDCS) which promises to overcome one of the main tDCS limitation (i.e., low focality) and its application for neurological disease, pain relief, and motor learning/rehabilitation. Finally, we provided information regarding the Transcutaneous Spinal Direct Current Stimulation (tsDCS) in clinical applications, Cerebellar tDCS (ctDCS) and its influence on motor learning, and TMS combined with electroencephalography (EEG) as a tool to evaluate tDCS effects on brain function.
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Affiliation(s)
- Edgard Morya
- Edmond and Lily Safra International Institute of Neuroscience, Santos Dumont Institute, Macaíba, Rio Grande do Norte Brazil
- Brazilian Institute of Neuroscience and Neurotechnology (BRAINN/CEPID-FAPESP), University of Campinas, Campinas, São Paulo, Brazil
| | - Kátia Monte-Silva
- Universidade Federal de Pernambuco, Recife, Pernambuco Brazil
- Núcleo de Assistência e Pesquisa em Neuromodulação (NAPeN), Universidade Federal do ABC (UFABC)/Universidade de São Paulo (USP)/Universidade Cidade de São Paulo (UNICID)/Universidade Federal de Pernambuco (UFPE), Escola Bahiana de Medicina e Saúde Pública (EBMSP), Santo André, Brazil
| | - Marom Bikson
- Department of Biomedical Engineering, The City College of New York of CUNY, New York, NY USA
| | - Zeinab Esmaeilpour
- Department of Biomedical Engineering, The City College of New York of CUNY, New York, NY USA
| | - Claudinei Eduardo Biazoli
- Center of Mathematics, Computing and Cognition (CMCC), Universidade Federal do ABC (UFABC), Alameda da Universidade, 3 - Anchieta, Bloco Delta – Sala 257, São Bernardo do Campo, SP CEP 09606-070 Brazil
| | - Andre Fonseca
- Brazilian Institute of Neuroscience and Neurotechnology (BRAINN/CEPID-FAPESP), University of Campinas, Campinas, São Paulo, Brazil
- Center of Mathematics, Computing and Cognition (CMCC), Universidade Federal do ABC (UFABC), Alameda da Universidade, 3 - Anchieta, Bloco Delta – Sala 257, São Bernardo do Campo, SP CEP 09606-070 Brazil
| | - Tommaso Bocci
- Aldo Ravelli Center for Neurotechnology and Experimental Brain Therapeutics, Department of Health Sciences, International Medical School, University of Milan, Milan, Italy
| | - Faranak Farzan
- School of Mechatronic Systems Engineering, Simon Fraser University, Surrey, British Columbia Canada
| | - Raaj Chatterjee
- School of Mechatronic Systems Engineering, Simon Fraser University, Surrey, British Columbia Canada
| | - Jeffrey M. Hausdorff
- Department of Physical Therapy, Sackler Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | | | | | - Eva Mezger
- Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany
| | - Luciane Aparecida Moscaleski
- Brazilian Institute of Neuroscience and Neurotechnology (BRAINN/CEPID-FAPESP), University of Campinas, Campinas, São Paulo, Brazil
- Center of Mathematics, Computing and Cognition (CMCC), Universidade Federal do ABC (UFABC), Alameda da Universidade, 3 - Anchieta, Bloco Delta – Sala 257, São Bernardo do Campo, SP CEP 09606-070 Brazil
| | - Rodrigo Pegado
- Graduate Program in Rehabilitation Science, Universidade Federal do Rio Grande do Norte, Santa Cruz, Rio Grande do Norte Brazil
| | - João Ricardo Sato
- Center of Mathematics, Computing and Cognition (CMCC), Universidade Federal do ABC (UFABC), Alameda da Universidade, 3 - Anchieta, Bloco Delta – Sala 257, São Bernardo do Campo, SP CEP 09606-070 Brazil
| | - Marcelo Salvador Caetano
- Center of Mathematics, Computing and Cognition (CMCC), Universidade Federal do ABC (UFABC), Alameda da Universidade, 3 - Anchieta, Bloco Delta – Sala 257, São Bernardo do Campo, SP CEP 09606-070 Brazil
| | - Kátia Nunes Sá
- Núcleo de Assistência e Pesquisa em Neuromodulação (NAPeN), Universidade Federal do ABC (UFABC)/Universidade de São Paulo (USP)/Universidade Cidade de São Paulo (UNICID)/Universidade Federal de Pernambuco (UFPE), Escola Bahiana de Medicina e Saúde Pública (EBMSP), Santo André, Brazil
- Escola Bahiana de Medicina e Saúde Pública, Salvador, Bahia Brazil
| | - Clarice Tanaka
- Núcleo de Assistência e Pesquisa em Neuromodulação (NAPeN), Universidade Federal do ABC (UFABC)/Universidade de São Paulo (USP)/Universidade Cidade de São Paulo (UNICID)/Universidade Federal de Pernambuco (UFPE), Escola Bahiana de Medicina e Saúde Pública (EBMSP), Santo André, Brazil
- Laboratório de Investigações Médicas-54, Universidade de São Paulo, São Paulo, São Paulo Brazil
| | - Li Min Li
- Brazilian Institute of Neuroscience and Neurotechnology (BRAINN/CEPID-FAPESP), University of Campinas, Campinas, São Paulo, Brazil
| | - Abrahão Fontes Baptista
- Brazilian Institute of Neuroscience and Neurotechnology (BRAINN/CEPID-FAPESP), University of Campinas, Campinas, São Paulo, Brazil
- Núcleo de Assistência e Pesquisa em Neuromodulação (NAPeN), Universidade Federal do ABC (UFABC)/Universidade de São Paulo (USP)/Universidade Cidade de São Paulo (UNICID)/Universidade Federal de Pernambuco (UFPE), Escola Bahiana de Medicina e Saúde Pública (EBMSP), Santo André, Brazil
- Center of Mathematics, Computing and Cognition (CMCC), Universidade Federal do ABC (UFABC), Alameda da Universidade, 3 - Anchieta, Bloco Delta – Sala 257, São Bernardo do Campo, SP CEP 09606-070 Brazil
- Escola Bahiana de Medicina e Saúde Pública, Salvador, Bahia Brazil
- Laboratório de Investigações Médicas-54, Universidade de São Paulo, São Paulo, São Paulo Brazil
| | - Alexandre Hideki Okano
- Brazilian Institute of Neuroscience and Neurotechnology (BRAINN/CEPID-FAPESP), University of Campinas, Campinas, São Paulo, Brazil
- Núcleo de Assistência e Pesquisa em Neuromodulação (NAPeN), Universidade Federal do ABC (UFABC)/Universidade de São Paulo (USP)/Universidade Cidade de São Paulo (UNICID)/Universidade Federal de Pernambuco (UFPE), Escola Bahiana de Medicina e Saúde Pública (EBMSP), Santo André, Brazil
- Center of Mathematics, Computing and Cognition (CMCC), Universidade Federal do ABC (UFABC), Alameda da Universidade, 3 - Anchieta, Bloco Delta – Sala 257, São Bernardo do Campo, SP CEP 09606-070 Brazil
- Graduate Program in Physical Education. State University of Londrina, Londrina, Paraná, Brazil
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Restless legs syndrome: Clinical changes in nervous system excitability at the spinal cord level. Sleep Med Rev 2019; 47:9-17. [PMID: 31212170 DOI: 10.1016/j.smrv.2019.05.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 04/30/2019] [Accepted: 05/27/2019] [Indexed: 12/20/2022]
Abstract
Restless legs syndrome (RLS) is a complex multifactorial disorder whose aetiology has yet to be fully elucidated. Some of the features of RLS, such as processing of sensations and activation of movement, may result from a dysfunction in spinal processing giving rise to a state of spinal hyperexcitability. In the current article we review studies investigating spinal excitability in RLS patients looking specifically at electrophysiological studies of spinal activity, sensory evaluations, and spinal reflex studies. Increased spinal excitability has been shown in RLS patients based on the combined data from electrophysiological studies. Results from studies assessing sensory evaluations in RLS patients show enhanced spinal processing of nociceptive inputs possibly due to central sensitisation. However, not all sensory modalities demonstrate an increase in sensitivity. An increase in nervous system excitability would result in an increase in reflex responses in RLS patients however the data from reflex analyses in RLS patients has failed to consistently show this expected result. Overall changes to RLS spinal excitability have been demonstrated though these changes might be heterogeneous as not all afferent input appears to be affected in the same manner. There may be phase-dependent and modality-dependent alterations in spinal excitability suggesting that the theory of absolute spinal hyperexcitability in RLS patients' needs to be reconsidered.
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28
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Awosika OO, Sandrini M, Volochayev R, Thompson RM, Fishman N, Wu T, Floeter MK, Hallett M, Cohen LG. Transcutaneous spinal direct current stimulation improves locomotor learning in healthy humans. Brain Stimul 2019; 12:628-634. [PMID: 30733143 PMCID: PMC7326485 DOI: 10.1016/j.brs.2019.01.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 10/08/2018] [Accepted: 01/24/2019] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND Ambulation is an essential aspect of daily living and is often impaired after brain and spinal cord injuries. Despite the implementation of standard neurorehabilitative care, locomotor recovery is often incomplete. OBJECTIVE In this randomized, sham-controlled, double-blind, parallel design study, we aimed to determine if anodal transcutaneous spinal direct current stimulation (anodal tsDCS) could improve training effects on locomotion compared to sham (sham tsDCS) in healthy subjects. METHODS 43 participants underwent a single backwards locomotion training (BLT) session on a reverse treadmill with concurrent anodal (n = 22) or sham (n = 21) tsDCS. The primary outcome measure was speed gain measured 24 h post-training. We hypothesized that anodal tsDCS + BLT would improve training effects on backward locomotor speed compared to sham tsDCS + BLT. A subset of participants (n = 31) returned for two additional training days of either anodal (n = 16) or sham (n = 15) tsDCS and underwent (n = 29) H-reflex testing immediately before, immediately after, and 30 min post-training over three consecutive days. RESULTS A single session of anodal tsDCS + BLT elicited greater speed gain at 24 h relative to sham tsDCS + BLT (p = 0.008, two-sample t-test, adjusted for one interim analysis after the initial 12 subjects). Anodal tsDCS + BLT resulted in higher retention of the acquired skill at day 30 relative to sham tsDCS + BLT (p = 0.002) in the absence of significant group differences in online or offline learning over the three training days (p = 0.467 and p = 0.131). BLT resulted in transient down-regulation of H-reflex amplitude (Hmax/Mmax) in both test groups (p < 0.0001). However, the concurrent application of anodal-tsDCS with BLT elicited a longer lasting effect than sham-tsDCS + BLT (p = 0.050). CONCLUSION tsDCS improved locomotor skill acquisition and retention in healthy subjects and prolonged the physiological exercise-mediated downregulation of excitability of the alpha motoneuron pool. These results suggest that this strategy is worth exploring in neurorehabilitation of locomotor function.
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Affiliation(s)
- Oluwole O Awosika
- Human Cortical Physiology and Neurorehabilitation Section, NINDS, USA; Department of Neurology and Rehabilitation Medicine, University of Cincinnati, USA.
| | - Marco Sandrini
- Human Cortical Physiology and Neurorehabilitation Section, NINDS, USA; Department of Psychology, University of Roehampton, London, UK
| | - Rita Volochayev
- Human Cortical Physiology and Neurorehabilitation Section, NINDS, USA
| | - Ryan M Thompson
- Human Cortical Physiology and Neurorehabilitation Section, NINDS, USA
| | - Nathan Fishman
- Human Cortical Physiology and Neurorehabilitation Section, NINDS, USA
| | | | | | | | - Leonardo G Cohen
- Human Cortical Physiology and Neurorehabilitation Section, NINDS, USA
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29
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Powell ES, Korupolu R, Westgate PM, Carrico C, Reddy L, Sawaki L. Dose-response relationship of transcutaneous spinal direct current stimulation in healthy humans: A proof of concept study. NeuroRehabilitation 2018; 43:369-376. [PMID: 30400116 DOI: 10.3233/nre-182469] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Non-invasive transcranial direct current stimulation has been shown to modulate cortical excitability in various studies. Similarly, recent preliminary studies suggest that transcutaneous spinal direct current stimulation (tsDCS) may engender a modulation effect on spinal and cortical neurons. OBJECTIVE The purpose of this study was to evaluate the dose-response effects of tsDCS in healthy subjects and thereby lay groundwork for expanding treatment options for patients with spinal cord injury (SCI). METHODS Nine healthy subjects received each of the following 2 tsDCS conditions: Anodal and cathodal, in random order with at least 1 week washout period between each session. In order to test safety and dose response, various current intensities were used (2, 2.5 and 3 mA) for 20 minutes. The active electrode was placed vertically over T10-T11, and the reference electrode was placed over the left shoulder. To evaluate corticospinal excitability, motor evoked potentials over soleus muscle elicited by transcranial magnetic stimulation were measured. To assess spinal cord excitability, H- and M- wave over soleus muscle to calculate Hmax/ Mmax ratio were measured. RESULTS Linear regression showed a dose response with cathodal tsDCS on motor evoked potentials measured from the left leg as well as with anodal tsDCS on Hmax/ Mmax ratio measured from the left leg. CONCLUSIONS These findings indicate tsDCS effects are dose-dependent. These effects should be investigated in a larger sample.
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Affiliation(s)
- Elizabeth Salmon Powell
- Department of Physical Medicine and Rehabilitation, University of Kentucky, Lexington, KY, USA
| | - Radha Korupolu
- Department of Physical Medicine and Rehabilitation, University of Texas Health Science Center, Houston, TX, USA
| | - Philip M Westgate
- Department of Biostatistics, College of Public Health, University of Kentucky, Lexington, KY, USA
| | - Cheryl Carrico
- Department of Physical Medicine and Rehabilitation, University of Kentucky, Lexington, KY, USA
| | - Lakshmi Reddy
- Department of Physical Medicine and Rehabilitation, University of Kentucky, Lexington, KY, USA
| | - Lumy Sawaki
- Department of Physical Medicine and Rehabilitation, University of Kentucky, Lexington, KY, USA.,Encompass Health Cardinal Hill Rehabilitation Hospital, Lexington, KY, USA
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Lenoir C, Jankovski A, Mouraux A. Anodal Transcutaneous Spinal Direct Current Stimulation (tsDCS) Selectively Inhibits the Synaptic Efficacy of Nociceptive Transmission at Spinal Cord Level. Neuroscience 2018; 393:150-163. [PMID: 30321585 DOI: 10.1016/j.neuroscience.2018.10.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2018] [Revised: 10/03/2018] [Accepted: 10/05/2018] [Indexed: 12/30/2022]
Abstract
Recently studies have aimed at developing transcutaneous spinal direct current stimulation (tsDCS) as a non-invasive technique to modulate spinal function in humans. Independent studies evaluating its after-effects on nociceptive or non-nociceptive somatosensory responses have reported comparable effects suggesting that tsDCS impairs axonal conduction of both the spino-thalamic and the medial lemniscus tracts. The present study aimed to better understand how tsDCS affects, in humans, the spinal transmission of nociceptive and non-nociceptive somatosensory inputs. We compared the after-effects of anodal low-thoracic, anodal cervical and sham tsDCS on the perception and brain responses elicited by laser stimuli selectively activating Aδ-thermonociceptors of the spinothalamic system and vibrotactile stimuli selectively activating low-threshold Aβ-mechanoreceptors of the lemniscal system, delivered to the hands and feet. Low-thoracic tsDCS selectively and significantly affected the LEP-N2 wave elicited by nociceptive stimulation of the lower limbs, without affecting the LEP-N2 wave elicited by nociceptive stimulation of the upper limbs, and without affecting the SEP-N2 wave elicited by vibrotactile stimulation of either limb. This selective and segmental effect indicates that the neuromodulatory after-effects of tsDCS cannot be explained by anodal blockade of axonal conduction and, instead, are most probably due to a segmental effect on the synaptic efficacy of the local processing and/or transmission of nociceptive inputs in the dorsal horn.
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Affiliation(s)
- Cédric Lenoir
- Institute of Neuroscience (IONS) Université catholique de Louvain (UCL), Brussels, Belgium.
| | - Aleksandar Jankovski
- Institute of Neuroscience (IONS) Université catholique de Louvain (UCL), Brussels, Belgium; Department of Neurosurgery, Université catholique de Louvain (UCL), CHU UCL Namur, Avenue Dr G. Therasse, 5530 Yvoir, Belgium.
| | - André Mouraux
- Institute of Neuroscience (IONS) Université catholique de Louvain (UCL), Brussels, Belgium.
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Pereira M, Fernandes SR, Miranda PC, de Carvalho M. Neuromodulation of lower limb motor responses with transcutaneous lumbar spinal cord direct current stimulation. Clin Neurophysiol 2018; 129:1999-2009. [PMID: 30041145 DOI: 10.1016/j.clinph.2018.07.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2018] [Revised: 06/03/2018] [Accepted: 07/02/2018] [Indexed: 12/29/2022]
Abstract
OBJECTIVE Trans-spinal direct current stimulation (tsDCS) is a promising technique to modulate spinal circuits. Combining clinical with modelling studies can improve effectiveness of tsDCS protocols. The aim of this study is to measure the effects of lumbar tsDCS on motor spinal responses and observe if these are consistent with the electric field (E-field) predicted from a computational model. METHODS The exploratory study design was double-blind crossover and randomized. tsDCS was delivered for 15 min (anodal, cathodal, sham) at L2 vertebra level (2.5 mA, 90 C/cm2) in 14 healthy subjects. F-wave, H-reflex, cortical silent period, motor evoked potential and sympathetic skin response were analyzed. Statistical methods were applied with Bonferroni correction for multiple comparisons, a p < 0.05 was set as significant. A human volume conductor model was obtained from available databases. E-field distributions in the spinal grey matter (GM) and white matter (WM) were calculated. RESULTS No tsDCS effects were observed. E-field magnitude predicted in the lumbosacral spinal GM and WM was <0.15 V/m, insufficient to ensure neuromodulation, which is consistent with the absence of effects. CONCLUSION The tsDCS protocol applied did not change motor response to delivered stimulus, thus we observed no effect on motor spinal circuits. SIGNIFICANCE Future tsDCS protocols should be supported by computational models.
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Affiliation(s)
- Mariana Pereira
- Instituto de Medicina Molecular, Instituto de Fisiologia, Faculdade de Medicina, Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028 Lisboa, Portugal
| | - Sofia Rita Fernandes
- Instituto de Medicina Molecular, Instituto de Fisiologia, Faculdade de Medicina, Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028 Lisboa, Portugal; Instituto de Biofísica e Engenharia Biomédica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Pedro C Miranda
- Instituto de Biofísica e Engenharia Biomédica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Mamede de Carvalho
- Instituto de Medicina Molecular, Instituto de Fisiologia, Faculdade de Medicina, Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028 Lisboa, Portugal; Departamento de Neurociências e Saúde Mental, Hospital de Santa Maria - Centro Hospitalar Lisboa Norte, Avenida Professor Egas Moniz, 1649-035 Lisboa, Portugal.
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Eftekhar A, Norton JJS, McDonough CM, Wolpaw JR. Retraining Reflexes: Clinical Translation of Spinal Reflex Operant Conditioning. Neurotherapeutics 2018; 15:669-683. [PMID: 29987761 PMCID: PMC6095771 DOI: 10.1007/s13311-018-0643-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Neurological disorders, such as spinal cord injury, stroke, traumatic brain injury, cerebral palsy, and multiple sclerosis cause motor impairments that are a huge burden at the individual, family, and societal levels. Spinal reflex abnormalities contribute to these impairments. Spinal reflex measurements play important roles in characterizing and monitoring neurological disorders and their associated motor impairments, such as spasticity, which affects nearly half of those with neurological disorders. Spinal reflexes can also serve as therapeutic targets themselves. Operant conditioning protocols can target beneficial plasticity to key reflex pathways; they can thereby trigger wider plasticity that improves impaired motor skills, such as locomotion. These protocols may complement standard therapies such as locomotor training and enhance functional recovery. This paper reviews the value of spinal reflexes and the therapeutic promise of spinal reflex operant conditioning protocols; it also considers the complex process of translating this promise into clinical reality.
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Affiliation(s)
- Amir Eftekhar
- National Center for Adaptive Neurotechnologies, Wadsworth Center, New York State Department of Health, Albany, NY, USA.
| | - James J S Norton
- National Center for Adaptive Neurotechnologies, Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | - Christine M McDonough
- School of Health and Rehabilitation Services, University of Pittsburgh, Pittsburgh, PA, USA
| | - Jonathan R Wolpaw
- National Center for Adaptive Neurotechnologies, Wadsworth Center, New York State Department of Health, Albany, NY, USA
- Department of Neurology, Stratton VA Medical Center, Albany, NY, USA
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Does trans-spinal direct current stimulation modulate the Hoffmann reflexes of healthy individuals? A systematic review and meta-analysisc. Spinal Cord 2018; 56:1022-1031. [PMID: 29895879 DOI: 10.1038/s41393-018-0149-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 03/23/2018] [Accepted: 03/29/2018] [Indexed: 12/27/2022]
Abstract
STUDY DESIGN Systematic review and meta-analysis. OBJECTIVES To summarize the available evidence regarding the effects of trans-spinal direct current stimulation (tsDCS) on spinal monosynaptic circuit excitability in healthy individuals. SETTING Applied Neuroscience Laboratory, Brazil. METHODS Abstract screening was performed independently by two authors for studies found in the following databases: PubMed, CINAHL, PsycINFO, Web of Science, and LILACS. If the authors were unable to agree, a third reviewer was consulted. Randomized clinical trials that reported monosynaptic reflex measures were included. Methodological quality was assessed using the Cochrane tool for assessing the risk of bias, and information extracted about the spinal neurophysiological and stimulation protocols and their results. RESULTS The initial search identified 538 studies. After applying the inclusion criteria and excluding duplicates, seven crossover studies were included in the risk of bias assessment, and six studies in the meta-analyses. The meta-analysis results did not show any significant differences between anodal (pooled standardized mean difference (SMD) = -0.09, 95% CI = -0.72 to 0.55, p = 0.79, I2 = 67%) or cathodal tsDCS (pooled SMD = 0.28, 95% CI = -0.07 to 0.63, p = 0.11, I2 = 0%) and sham tsDCS for Hoffmann reflex modulation. CONCLUSION tsDCS did not affect the Hoffmann reflex, as shown in six studies. However, these findings come from studies with selection, performance and detection bias, and further research is needed to examine the effect of this intervention.
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Albuquerque PL, Campêlo M, Mendonça T, Fontes LAM, Brito RDM, Monte-Silva K. Effects of repetitive transcranial magnetic stimulation and trans-spinal direct current stimulation associated with treadmill exercise in spinal cord and cortical excitability of healthy subjects: A triple-blind, randomized and sham-controlled study. PLoS One 2018; 13:e0195276. [PMID: 29596524 PMCID: PMC5875883 DOI: 10.1371/journal.pone.0195276] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 03/18/2018] [Indexed: 11/18/2022] Open
Abstract
Repetitive transcranial magnetic stimulation (rTMS) over motor cortex and trans-spinal direct current stimulation (tsDCS) modulate corticospinal circuits in healthy and injured subjects. However, their associated effects with physical exercise is still not defined. This study aimed to investigate the effect of three different settings of rTMS and tsDCS combined with treadmill exercise on spinal cord and cortical excitability of healthy subjects. We performed a triple blind, randomized, sham-controlled crossover study with 12 healthy volunteers who underwent single sessions of rTMS (1Hz, 20Hz and Sham) and tsDCS (anodal, cathodal and Sham) associated with 20 minutes of treadmill walking. Cortical excitability was assessed by motor evoked potential (MEP) and spinal cord excitability by the Hoffmann reflex (Hr), nociceptive flexion reflex (NFR) and homosynaptic depression (HD). All measures were assessed before, immediately, 30 and 60 minutes after the experimental procedures. Our results demonstrated that anodal tsDCS/treadmill exercise reduced MEP's amplitude and NFR's area compared to sham condition, conversely, cathodal tsDCS/treadmill exercise increased NFR's area. High-frequency rTMS increased MEP's amplitude and NFR's area compared to sham condition. Anodal tsDCS/treadmill exercise and 20Hz rTMS/treadmill exercise reduced Hr amplitude up to 30 minutes after stimulation offset and no changes were observed in HD measures. We demonstrated that tsDCS and rTMS combined with treadmill exercise modulated cortical and spinal cord excitability through different mechanisms. tsDCS modulated spinal reflexes in a polarity-dependent way acting at local spinal circuits while rTMS probably promoted changes in the presynaptic inhibition of spinal motoneurons. In addition, the association of two neuromodulatory techniques induced long-lasting changes.
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Affiliation(s)
- Plínio Luna Albuquerque
- Applied Neuroscience Laboratory, Department of Physical Therapy, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil
- Department of Physical Therapy, Centro Universitário Tabosa de Almeida, Caruaru, Pernambuco, Brazil
- Postgraduate Program in Neuropsychiatry and Behavioral Sciences, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil
| | - Mayara Campêlo
- Applied Neuroscience Laboratory, Department of Physical Therapy, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil
- Postgraduate Program in Neuropsychiatry and Behavioral Sciences, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil
| | - Thyciane Mendonça
- Applied Neuroscience Laboratory, Department of Physical Therapy, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil
| | - Luís Augusto Mendes Fontes
- Applied Neuroscience Laboratory, Department of Physical Therapy, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil
| | - Rodrigo de Mattos Brito
- Applied Neuroscience Laboratory, Department of Physical Therapy, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil
| | - Katia Monte-Silva
- Applied Neuroscience Laboratory, Department of Physical Therapy, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil
- Postgraduate Program in Neuropsychiatry and Behavioral Sciences, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil
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Kuck A, Stegeman DF, van der Kooij H, van Asseldonk EHF. Changes in H-Reflex Recruitment After Trans-Spinal Direct Current Stimulation With Multiple Electrode Configurations. Front Neurosci 2018; 12:151. [PMID: 29643759 PMCID: PMC5882846 DOI: 10.3389/fnins.2018.00151] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Accepted: 02/26/2018] [Indexed: 01/11/2023] Open
Abstract
Trans-spinal direct current stimulation (tsDCS) is an electro-modulatory tool with possible application in the rehabilitation of spinal cord injury. TsDCS generates a small electric field, aiming to induce lasting, functional neuromodulation in the targeted neuronal networks. Earlier studies have shown significant modulatory effects after application of lumbar tsDCS. However, for clinical application, a better understanding of application specific factors is required. Our goal was to investigate the effect of different electrode configurations using lumbar spinal tsDCS on spinal excitability. We applied tsDCS (2.5 mA, 15 min) in 10 healthy subjects with three different electrode configurations: (1) Anode and cathode placed over vertebra T11, and the posterior left shoulder respectively (LSC-S) (one polarity), and (2) Both electrodes placed in equal distance (ED) (7 cm) above and below vertebra T11, investigated for two polarities (ED-Anodal/Cathodal). The soleus H-Reflex is measured before, during and after tsDCS in either electrode configuration or a sham condition. To account for genetic predispositions in response to direct current stimulation, subject BDNF genotype was assessed. Stimulation in configuration ED-Cathodal induced an amplitude reduction of the H-reflex, 30 min after tsDCS with respect to baseline, whereas none of the other configurations led to significant post intervention effects. BDNF genotype did not correlate with post intervention effects. Furthermore, we failed to replicate effects shown by a previous study, which highlights the need for a better understanding of methodological and subject specific influences on tsDCS outcome. The H-reflex depression after tsDCS (Config. ED-Cathodal) provides new insights and may foster our understanding of the working mechanism of tsDCS.
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Affiliation(s)
- Alexander Kuck
- Laboratory of Biomechanical Engineering, Department of Engineering Technology, University of Twente, Enschede, Netherlands.,Neuronal Rhythms in Movement Unit, Okinawa Institute of Science and Technology Graduate University, Onna-son, Japan
| | - Dick F Stegeman
- Department of Neurology/Clinical Neurophysiology, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behavior, Nijmegen, Netherlands
| | - Herman van der Kooij
- Laboratory of Biomechanical Engineering, Department of Engineering Technology, University of Twente, Enschede, Netherlands.,Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Delft, Netherlands
| | - Edwin H F van Asseldonk
- Laboratory of Biomechanical Engineering, Department of Engineering Technology, University of Twente, Enschede, Netherlands
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Jimenez S, Mordillo-Mateos L, Dileone M, Campolo M, Carrasco-Lopez C, Moitinho-Ferreira F, Gallego-Izquierdo T, Siebner HR, Valls-Solé J, Aguilar J, Oliviero A. Effects of patterned peripheral nerve stimulation on soleus spinal motor neuron excitability. PLoS One 2018; 13:e0192471. [PMID: 29451889 PMCID: PMC5815584 DOI: 10.1371/journal.pone.0192471] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 01/03/2018] [Indexed: 11/24/2022] Open
Abstract
Spinal plasticity is thought to contribute to sensorimotor recovery of limb function in several neurological disorders and can be experimentally induced in animals and humans using different stimulation protocols. In healthy individuals, electrical continuous Theta Burst Stimulation (TBS) of the median nerve has been shown to change spinal motoneuron excitability in the cervical spinal cord as indexed by a change in mean H-reflex amplitude in the flexor carpi radialis muscle. It is unknown whether continuous TBS of a peripheral nerve can also shift motoneuron excitability in the lower limb. In 26 healthy subjects, we examined the effects of electrical TBS given to the tibial nerve in the popliteal fossa on the excitability of lumbar spinal motoneurons as measured by H-reflex amplitude of the soleus muscle evoked by tibial nerve stimulation. Continuous TBS was given at 110% of H-reflex threshold intensity and compared to non-patterned regular electrical stimulation at 15 Hz. To disclose any pain-induced effects, we also tested the effects of TBS at individual sensory threshold. Moreover, in a subgroup of subjects we evaluated paired-pulse inhibition of H-reflex. Continuous TBS at 110% of H-reflex threshold intensity induced a short-term reduction of H-reflex amplitude. The other stimulation conditions produced no after effects. Paired-pulse H-reflex inhibition was not modulated by continuous TBS or non-patterned repetitive stimulation at 15 Hz. An effect of pain on the results obtained was discarded, since non-patterned 15 Hz stimulation at 110% HT led to pain scores similar to those induced by EcTBS at 110% HT, but was not able to induce any modulation of the H reflex amplitude. Together, the results provide first time evidence that peripheral continuous TBS induces a short-lasting change in the excitability of spinal motoneurons in lower limb circuitries. Future studies need to investigate how the TBS protocol can be optimized to produce a larger and longer effect on spinal cord physiology and whether this might be a useful intervention in patients with excessive excitability of the spinal motorneurons.
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Affiliation(s)
- Samuel Jimenez
- FENNSI Group, Hospital Nacional de Parapléjicos, SESCAM, Toledo, Spain
- Physiotherapy Department, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid, Spain
- Physiotherapy Department, Alcalá de Henares University, Alcalá de Henares Spain
| | | | - Michele Dileone
- FENNSI Group, Hospital Nacional de Parapléjicos, SESCAM, Toledo, Spain
- CINAC, HM Puerta del Sur, Hospitales de Madrid, Móstoles, Spain
| | - Michela Campolo
- FENNSI Group, Hospital Nacional de Parapléjicos, SESCAM, Toledo, Spain
- EMG and Motor Control Section, Neurology Department, Hospital Clinic, University of Barcelona, Barcelona, Spain
| | | | - Fabricia Moitinho-Ferreira
- FENNSI Group, Hospital Nacional de Parapléjicos, SESCAM, Toledo, Spain
- Sarah Network of Rehabilitation Hospitals, Salvador de Bahia, Brazil
| | | | - Hartwig R. Siebner
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital, Hvidovre, Hvidovre, Denmark
- Department of Neurology, Copenhagen University Hospital Bispebjerg, Copenhagen, Denmark
| | - Josep Valls-Solé
- EMG and Motor Control Section, Neurology Department, Hospital Clinic, University of Barcelona, Barcelona, Spain
| | - Juan Aguilar
- Experimental Neurophysiology Group, Hospital Nacional de Parapléjicos, SESCAM, Toledo, Spain
| | - Antonio Oliviero
- FENNSI Group, Hospital Nacional de Parapléjicos, SESCAM, Toledo, Spain
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Fernandes SR, Salvador R, Wenger C, de Carvalho M, Miranda PC. Transcutaneous spinal direct current stimulation of the lumbar and sacral spinal cord: a modelling study. J Neural Eng 2018; 15:036008. [PMID: 29386408 DOI: 10.1088/1741-2552/aaac38] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
OBJECTIVE Our aim was to perform a computational study of the electric field (E-field) generated by transcutaneous spinal direct current stimulation (tsDCS) applied over the thoracic, lumbar and sacral spinal cord, in order to assess possible neuromodulatory effects on spinal cord circuitry related with lower limb functions. APPROACH A realistic volume conductor model of the human body consisting of 14 tissues was obtained from available databases. Rubber pad electrodes with a metallic connector and a conductive gel layer were modelled. The finite element (FE) method was used to calculate the E-field when a current of 2.5 mA was passed between two electrodes. The main characteristics of the E-field distributions in the spinal grey matter (spinal-GM) and spinal white matter (spinal-WM) were compared for seven montages, with the anode placed either over T10, T8 or L2 spinous processes (s.p.), and the cathode placed over right deltoid (rD), umbilicus (U) and right iliac crest (rIC) areas or T8 s.p. Anisotropic conductivity of spinal-WM and of a group of dorsal muscles near the vertebral column was considered. MAIN RESULTS The average E-field magnitude was predicted to be above 0.15 V m-1 in spinal cord regions located between the electrodes. L2-T8 and T8-rIC montages resulted in the highest E-field magnitudes in lumbar and sacral spinal segments (>0.30 V m-1). E-field longitudinal component is 3 to 6 times higher than the ventral-dorsal and right-left components in both the spinal-GM and WM. Anatomical features such as CSF narrowing due to vertebrae bony edges or disks intrusions in the spinal canal correlate with local maxima positions. SIGNIFICANCE Computational modelling studies can provide detailed information regarding the electric field in the spinal cord during tsDCS. They are important to guide the design of clinical tsDCS protocols that optimize stimulation of application-specific spinal targets.
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Affiliation(s)
- Sofia R Fernandes
- Instituto de Biofísica e Engenharia Biomédica, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016, Lisboa, Portugal. Instituto de Fisiologia, Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Av. Professor Egas Moniz, 1649-028 Lisboa, Portugal
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Transspinal Direct Current Stimulation Produces Persistent Plasticity in Human Motor Pathways. Sci Rep 2018; 8:717. [PMID: 29335430 PMCID: PMC5768745 DOI: 10.1038/s41598-017-18872-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 12/19/2017] [Indexed: 11/25/2022] Open
Abstract
The spinal cord is an integration center for descending, ascending, and segmental neural signals. Noninvasive transspinal stimulation may thus constitute an effective method for concomitant modulation of local and distal neural circuits. In this study, we established changes in cortical excitability and input/output function of corticospinal and spinal neural circuits before, at 0–15 and at 30–45 minutes after cathodal, anodal, and sham transspinal direct current stimulation (tsDCS) to the thoracic region in healthy individuals. We found that intracortical inhibition was different among stimulation polarities, however remained unchanged over time. Intracortical facilitation increased after cathodal and anodal tsDCS delivered with subjects seated, and decreased after cathodal tsDCS delivered with subjects lying supine. Both cathodal and anodal tsDCS increased corticospinal excitability, yet facilitation was larger and persisted for 30 minutes post stimulation only when cathodal tsDCS was delivered with subjects lying supine. Spinal input/output reflex function was decreased by cathodal and not anodal tsDCS. These changes may be attributed to altered spontaneous neural activity and membrane potentials of corticomotoneuronal cells by tsDCS involving similar mechanisms to those mediating motor learning. Our findings indicate that thoracic tsDCS has the ability to concomitantly alter cortical, corticospinal, and spinal motor output in humans.
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Powell ES, Carrico C, Salyers E, Westgate PM, Sawaki L. The effect of transcutaneous spinal direct current stimulation on corticospinal excitability in chronic incomplete spinal cord injury. NeuroRehabilitation 2018; 43:125-134. [PMID: 30040753 PMCID: PMC6130412 DOI: 10.3233/nre-172369] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
OBJECTIVES This study investigated the feasibility of modulating bilateral corticospinal excitability with different polarities of transcutaneous spinal direct current stimulation (tsDCS) in chronic, incomplete spinal cord injury (SCI). METHODS Six subjects with chronic incomplete SCI (>12 months post injury) participated in this crossover study. Intervention consisted of 3 sessions, separated by at least 1 week, in which each subject received the conditions cathodal, anodal, and sham tsDCS. Stimulation was delivered at 2.5 mA for 20 minutes with the active electrode positioned over the spinous processes of T10-T11 and the reference electrode over left deltoid. To measure the effects of tsDCS on corticospinal excitability, motor evoked potentials (MEPs) from transcranial magnetic stimulation were measured bilaterally from soleus before and after tsDCS. RESULTS Five subjects completed all 3 sessions. One subject withdrew after 2 sessions due to complications unrelated to the study. MEPs were measurable in 5 subjects. No significant differences in change of MEP amplitudes were found between the 3 conditions. However, there were trends that indicated laterality of response, particularly with cathodal tsDCS increasing corticospinal excitability contralateral to the reference electrode and decreasing corticospinal excitability ipsilateral to the reference electrode. CONCLUSION Corticospinal excitability may be modulated with laterality by tsDCS in individuals with chronic, incomplete SCI. Further research is needed to 1) determine whether different placement of the reference electrode can lead to uniform modulation bilaterally, and 2) reveal whether these alterations in corticospinal excitability can lead to improved movement function in individuals with chronic, incomplete SCI.
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Affiliation(s)
- Elizabeth Salmon Powell
- Department of Physical Medicine and Rehabilitation, University of Kentucky, Lexington, KY, USA
| | - Cheryl Carrico
- Department of Physical Medicine and Rehabilitation, University of Kentucky, Lexington, KY, USA
| | - Emily Salyers
- Department of Physical Medicine and Rehabilitation, University of Kentucky, Lexington, KY, USA
| | - Philip M. Westgate
- Department of Biostatistics, College of Public Health, University of Kentucky, Lexington, KY, USA
| | - Lumy Sawaki
- Department of Physical Medicine and Rehabilitation, University of Kentucky, Lexington, KY, USA
- HealthSouth Cardinal Hill Hospital, Lexington, KY, USA
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Dongés SC, Bai S, Taylor JL. Concurrent electrical cervicomedullary stimulation and cervical transcutaneous spinal direct current stimulation result in a stimulus interaction. Exp Physiol 2017; 102:1309-1320. [PMID: 28730695 DOI: 10.1113/ep086360] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 07/03/2017] [Indexed: 01/19/2023]
Abstract
NEW FINDINGS What is the central question of this study? We previously showed that the motor pathway is not modified after cervical transcutaneous spinal direct current stimulation (tsDCS) applied using anterior-posterior electrodes. Here, we examine the motor pathway during stimulation. What is the main finding and its importance? We show that electrically elicited muscle responses to cervicomedullary stimulation are modified during tsDCS, whereas magnetically elicited responses are not. Modelling reveals electrical field modifications during concurrent tsDCS and electrical cervicomedullary stimulation. Changes in muscle response probably result from electrical field modifications rather than physiological changes. Care should be taken when applying electrical stimuli simultaneously. Transcutaneous spinal direct current stimulation (tsDCS) can modulate neuronal excitability within the human spinal cord; however, few studies have used tsDCS at a cervical level. This study aimed to characterize cervical tsDCS further by observing its acute effects on motor responses to transcranial magnetic stimulation and cervicomedullary stimulation. In both studies 1 and 2, participants (study 1, n = 8, four female; and study 2, n = 8, three female) received two periods of 10 min, 3 mA cervical tsDCS on the same day through electrodes placed in an anterior-posterior configuration over the neck; one period with the cathode posterior (c-tsDCS) and the other with the anode posterior (a-tsDCS). In study 1, electrically elicited cervicomedullary motor evoked potentials (eCMEPs) and transcranial magnetic stimulation-elicited motor evoked potentials (MEPs) were measured in biceps brachii and flexor carpi radialis before, during and after each tsDCS period. In study 2, eCMEPs and magnetically elicited CMEPs (mCMEPs) were measured before, during and after each tsDCS period. For study 3, computational modelling was used to observe possible interactions of cervical tsDCS and electrical cervicomedullary stimulation. Studies 1 and 2 revealed that eCMEPs were larger during c-tsDCS and smaller during a-tsDCS compared with those elicited when tsDCS was off (P < 0.05), with no changes in MEPs or mCMEPs. Modelling revealed that eCMEP changes might result from modifications of the electrical field direction and magnitude when combined with cervical tsDCS. Bidirectional eCMEP changes are likely to be caused by an interaction between cervical tsDCS and electrical cervicomedullary stimulation; therefore, care should be taken when combining such electrical stimuli in close proximity.
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Affiliation(s)
- Siobhan C Dongés
- Neuroscience Research Australia, Barker Street, Randwick, NSW, 2031, Australia.,University of New South Wales, Sydney, NSW, 2052, Australia
| | - Siwei Bai
- University of New South Wales, Sydney, NSW, 2052, Australia.,Faculty of Electrical and Computer Engineering, Technical University of Munich, Garching, Germany
| | - Janet L Taylor
- Neuroscience Research Australia, Barker Street, Randwick, NSW, 2031, Australia.,University of New South Wales, Sydney, NSW, 2052, Australia.,Edith Cowan University, Joondalup, WA, 6027, Australia
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41
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Schweizer L, Meyer-Frießem CH, Zahn PK, Tegenthoff M, Schmidt-Wilcke T. Transcutaneous Spinal Direct Current Stimulation Alters Resting-State Functional Connectivity. Brain Connect 2017; 7:357-365. [DOI: 10.1089/brain.2017.0505] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Lauren Schweizer
- Department of Neurology, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH Bochum, Ruhr-University Bochum, Bochum, Germany
| | - Christine H. Meyer-Frießem
- Department of Anesthesiology, Intensive Care Medicine, Palliative Care Medicine and Pain Management, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH Bochum, Medical Faculty of Ruhr-University Bochum, Bochum, Germany
| | - Peter K. Zahn
- Department of Anesthesiology, Intensive Care Medicine, Palliative Care Medicine and Pain Management, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH Bochum, Medical Faculty of Ruhr-University Bochum, Bochum, Germany
| | - Martin Tegenthoff
- Department of Neurology, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH Bochum, Ruhr-University Bochum, Bochum, Germany
| | - Tobias Schmidt-Wilcke
- Department of Neurology, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH Bochum, Ruhr-University Bochum, Bochum, Germany
- Department of Clinical Neuroscience and Medical Psychology, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
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42
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Kuck A, Stegeman DF, van Asseldonk EHF. Modeling trans-spinal direct current stimulation for the modulation of the lumbar spinal motor pathways. J Neural Eng 2017. [PMID: 28631619 DOI: 10.1088/1741-2552/aa7960] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
OBJECTIVE Trans-spinal direct current stimulation (tsDCS) is a potential new technique for the treatment of spinal cord injury (SCI). TsDCS aims to facilitate plastic changes in the neural pathways of the spinal cord with a positive effect on SCI recovery. To establish tsDCS as a possible treatment option for SCI, it is essential to gain a better understanding of its cause and effects. We seek to understand the acute effect of tsDCS, including the generated electric field (EF) and its polarization effect on the spinal circuits, to determine a cellular target. We further ask how these findings can be interpreted to explain published experimental results. APPROACH We use a realistic full body finite element volume conductor model to calculate the EF of a 2.5 mA direct current for three different electrode configurations. We apply the calculated electric field to realistic motoneuron models to investigate static changes in membrane resting potential. The results are combined with existing knowledge about the theoretical effect on a neuronal level and implemented into an existing lumbar spinal network model to simulate the resulting changes on a network level. MAIN RESULTS Across electrode configurations, the maximum EF inside the spinal cord ranged from 0.47 V m-1 to 0.82 V m-1. Axon terminal polarization was identified to be the dominant cellular target. Also, differences in electrode placement have a large influence on axon terminal polarization. Comparison between the simulated acute effects and the electrophysiological long-term changes observed in human tsDCS studies suggest an inverse relationship between the two. SIGNIFICANCE We provide methods and knowledge for better understanding the effects of tsDCS and serve as a basis for a more targeted and optimized application of tsDCS.
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Affiliation(s)
- A Kuck
- University of Twente, Drienerlolaan 5, 7522 NB Enschede, Netherlands
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43
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Jankowska E. Spinal control of motor outputs by intrinsic and externally induced electric field potentials. J Neurophysiol 2017; 118:1221-1234. [PMID: 28539396 DOI: 10.1152/jn.00169.2017] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 05/22/2017] [Accepted: 05/22/2017] [Indexed: 12/13/2022] Open
Abstract
Despite numerous studies on spinal neuronal systems, several issues regarding their role in motor behavior remain unresolved. One of these issues is how electric fields associated with the activity of spinal neurons influence the operation of spinal neuronal networks and how effects of these field potentials are combined with other means of modulating neuronal activity. Another closely related issue is how external electric field potentials affect spinal neurons and how they can be used for therapeutic purposes such as pain relief or recovery of motor functions by transspinal direct current stimulation. Nevertheless, progress in our understanding of the spinal effects of electric fields and their mechanisms has been made over the last years, and the aim of the present review is to summarize the recent findings in this field.
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Affiliation(s)
- Elzbieta Jankowska
- Department of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Sweden
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44
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Schweizer LM, Zahn PK, Pogatzki-Zahn EM, Magerl W, Tegenthoff M, Meyer-Frießem CH. Influence of transcutaneous spinal stimulation on human LTP-like pain amplification. A randomized, double-blind study in volunteers. Clin Neurophysiol 2017; 128:1413-1420. [PMID: 28618292 DOI: 10.1016/j.clinph.2017.05.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2016] [Revised: 04/30/2017] [Accepted: 05/08/2017] [Indexed: 02/05/2023]
Abstract
OBJECTIVE Transcutaneous spinal direct current stimulation (tsDCS) has been proven to affect nociceptive signal processing. We designed a randomized, double-blind, cross-over study to investigate whether tsDCS applied before or after inducing long-term potentiation-(LTP)-like hyperalgesia may decrease nociceptive sensitivity. METHODS In healthy volunteers, tsDCS (2.5mA, 15min) was applied to the thoracic spine prior (n=14) or immediately following (n=12) electrical high-frequency stimulation (HFS) to the thigh, inducing hyperalgesia. Mechanical and electrical perception were assessed before HFS stimulation and at three time points following HFS stimulation (all within 90min of HFS). Subjects took part in three separate sessions to test effects of anodal, cathodal, or sham tsDCS. RESULTS Within 60minHFS led to unilateral changes on the conditioned side: mechanical pain thresholds tended to decrease and electrical detection thresholds significantly decreased (p<0.001); pain ratings measured using the numerical rating scale (NRS) increased for electrical stimuli (p<0.01) and two categories of mechanical stimuli ("Light(8-64mN)": p=ns; "Heavy(128-512mN)": p<0.01). Irrespective of stimulation order or polarity, tsDCS could not influence nociceptive sensitivity. CONCLUSION Hyperalgesia was adequately induced, but tsDCS had no effect on HFS-induced sensitization. SIGNIFICANCE While tsDCS has been shown to affect pain measures, our results suggest irrespective of time of stimulation or polarity that tsDCS may be less effective in modulating pain in a sensitized state in healthy subjects.
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Affiliation(s)
- L M Schweizer
- Department of Neurology, Ruhr-University Bochum, BG-Kliniken Bergmannsheil, Bürkle-de-la-Camp-Platz 1, 44789 Bochum, Germany
| | - P K Zahn
- Department of Anaesthesiology, Intensive Care Medicine, Palliative Care Medicine and Pain Management, Medical Faculty of Ruhr-University, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH Bochum, Bürkle-de-la-Camp-Platz 1, 44789 Bochum, Germany
| | - E M Pogatzki-Zahn
- Department of Anaesthesiology, Intensive Care and Pain Medicine, University Hospital of Muenster, Albert-Schweitzer-Campus 1 (Building A1), 48149 Münster, Germany
| | - W Magerl
- Department of Neurophysiology, Center of Biomedicine and Medical Technology (CBTM), Medical Faculty Mannheim, Ruprecht-Karls-University Heidelberg, Ludolf-Krehl-Str. 13, 68167 Mannheim, Germany
| | - M Tegenthoff
- Department of Neurology, Ruhr-University Bochum, BG-Kliniken Bergmannsheil, Bürkle-de-la-Camp-Platz 1, 44789 Bochum, Germany
| | - C H Meyer-Frießem
- Department of Anaesthesiology, Intensive Care Medicine, Palliative Care Medicine and Pain Management, Medical Faculty of Ruhr-University, Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil GmbH Bochum, Bürkle-de-la-Camp-Platz 1, 44789 Bochum, Germany.
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45
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Berry HR, Tate RJ, Conway BA. Transcutaneous spinal direct current stimulation induces lasting fatigue resistance and enhances explosive vertical jump performance. PLoS One 2017; 12:e0173846. [PMID: 28379980 PMCID: PMC5381869 DOI: 10.1371/journal.pone.0173846] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 02/27/2017] [Indexed: 01/05/2023] Open
Abstract
Transcutaneous spinal direct current stimulation (tsDCS) is a non-invasive neuromodulatory intervention that has been shown to modify excitability in spinal and supraspinal circuits in animals and humans. Our objective in this study was to explore the functional neuromodulatory potential of tsDCS by examining its immediate and lasting effects over the repeated performance of a whole body maximal exercise in healthy volunteers. Using a double-blind, randomized, crossover, sham-controlled design we investigated the effects of 15 min of anodal tsDCS on repeated vertical countermovement jump (VCJ) performance at 0, 20, 60, and 180 minutes post-stimulation. Measurements of peak and take-off velocity, vertical displacement, peak power and work done during countermovement and push-off VCJ phases were derived from changes in vertical ground reaction force (12 performance parameters) in 12 healthy participants. The magnitude and direction of change in VCJ performance from pre- to post-stimulation differed significantly between sham and active tsDCS for 7 of the 12 VCJ performance measures (P < 0.05). These differences comprised of a post-sham fatigue in VCJ displacement/work done, peak to peak power and take-off velocity, and a resilience to this fatigue effect post-active tsDCS. In addition there was also an enhancement of countermovement performance and total work done (P < 0.05). These changes did not vary across repeated VCJ performances over time post-tsDCS (P > 0.05). Our original findings demonstrate that one single session of anodal tsDCS in healthy subjects can prevent fatigue and maintain or enhance different aspects of whole body explosive motor power over repeated sets of VCJs performed over a period of three hours. The observed effects are discussed in relation to alterations in central fatigue mechanisms, muscle contraction mode during jump execution and changes in spinal cord excitability. These findings have important implications for power endurance sport performance and for neuromotor rehabilitation.
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Affiliation(s)
- Helen R. Berry
- Centre for Excellence in Rehabilitation Research, Department of Biomedical Engineering, University of Strathclyde, Glasgow, United Kingdom
- * E-mail:
| | - Rothwelle J. Tate
- Strathclyde Institute for Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
| | - Bernard A. Conway
- Centre for Excellence in Rehabilitation Research, Department of Biomedical Engineering, University of Strathclyde, Glasgow, United Kingdom
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Alhassani G, Treleaven J, Schabrun SS. Combined transcranial and trans-spinal direct current stimulation in chronic headache: A feasibility and safety trial for a novel intervention. Hong Kong Physiother J 2017; 37:1-9. [PMID: 30931040 PMCID: PMC6385152 DOI: 10.1016/j.hkpj.2016.11.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Background: Chronic primary headache disorders are associated with frequent, severe pain and significant functional impairment, with treatment remaining challenging. Objective: We examined the feasibility and safety of a novel brain [transcranial direct current stimulation (tDCS)] and spinal cord stimulation [trans-spinal cord direct current stimulation (tsDCS)] treatment in chronic headache. Methods: Nine participants (3 males; aged, 40 ± 15 years) suffering from chronic daily headache, chronic tension-type headache, or chronic migraine received the combined brain and spinal cord intervention for 5 consecutive days. Stimulation was applied for a total of 40 minutes (20 minutes of tDCS followed by 20 minutes of tsDCS) at 1 mA. Pain sensitivity and headache symptoms (frequency, severity, duration, and medications recorded via a headache diary, 4 weeks before and after treatment) were assessed. Results: The treatment was safe, feasible, and well tolerated. Headache frequency was reduced following the treatment (p = 0.026) in chronic tension-type headache and chronic migraine, but not in chronic daily headache. Headache severity was reduced immediately post-treatment in 67% of sessions. A trend towards a reduction in medication use was observed (p = 0.075). No changes in headache severity (p = 0.16) or duration (p = 0.34) were present. Conclusion: These data suggest that combined tDCS and tsDCS intervention is safe and feasible, and may improve headache frequency in patients with chronic primary headache disorders.
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Affiliation(s)
- Ghufran Alhassani
- Brain Rehabilitation and Neuroplasticity Unit, Western Sydney University, Sydney, New South Wales, Australia
| | - Julia Treleaven
- School of Health and Rehabilitation Science, The University of Queensland, Brisbane, Queensland, Australia
| | - Siobhan S.M. Schabrun
- Brain Rehabilitation and Neuroplasticity Unit, Western Sydney University, Sydney, New South Wales, Australia
- Corresponding author. Brain Rehabilitation and Neuroplasticity Unit, Western Sydney University, Campbelltown Campus, Locked Bag 1797, Penrith, New South Wales 2751, Australia. E-mail address: (S.S.M. Schabrun)
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47
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Dongés SC, D’Amico JM, Butler JE, Taylor JL. The effects of cervical transcutaneous spinal direct current stimulation on motor pathways supplying the upper limb in humans. PLoS One 2017; 12:e0172333. [PMID: 28225813 PMCID: PMC5321432 DOI: 10.1371/journal.pone.0172333] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2015] [Accepted: 01/08/2017] [Indexed: 12/29/2022] Open
Abstract
Non-invasive, weak direct current stimulation can induce changes in excitability of underlying neural tissue. Many studies have used transcranial direct current stimulation to induce changes in the brain, however more recently a number of studies have used transcutaneous spinal direct current stimulation to induce changes in the spinal cord. This study further characterises the effects following cervical transcutaneous spinal direct current stimulation on motor pathways supplying the upper limb. In Study 1, on two separate days, participants (n = 12, 5 F) received 20 minutes of either real or sham direct current stimulation at 3 mA through electrodes placed in an anterior-posterior configuration over the neck (anode anterior). Biceps brachii, flexor carpi radialis and first dorsal interosseous responses to transcranial magnetic stimulation (motor evoked potentials) and cervicomedullary stimulation (cervicomedullary motor evoked potentials) were measured before and after real or sham stimulation. In Study 2, on two separate days, participants (n = 12, 7 F) received either real or sham direct current stimulation in the same way as for Study 1. Before and after real or sham stimulation, median nerve stimulation elicited M waves and H reflexes in the flexor carpi radialis. H-reflex recruitment curves and homosynaptic depression of the H reflex were assessed. Results show that the effects of real and sham direct current stimulation did not differ for motor evoked potentials or cervicomedullary motor evoked potentials for any muscle, nor for H-reflex recruitment curve parameters or homosynaptic depression. Cervical transcutaneous spinal direct current stimulation with the parameters described here does not modify motor responses to corticospinal stimulation nor does it modify H reflexes of the upper limb. These results are important for the emerging field of transcutaneous spinal direct current stimulation.
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Affiliation(s)
- Siobhan C. Dongés
- Neuroscience Research Australia, Barker Street, Randwick, New South Wales, Australia
- University of New South Wales, Sydney, New South Wales, Australia
| | - Jessica M. D’Amico
- Neuroscience Research Australia, Barker Street, Randwick, New South Wales, Australia
| | - Jane E. Butler
- Neuroscience Research Australia, Barker Street, Randwick, New South Wales, Australia
- University of New South Wales, Sydney, New South Wales, Australia
| | - Janet L. Taylor
- Neuroscience Research Australia, Barker Street, Randwick, New South Wales, Australia
- University of New South Wales, Sydney, New South Wales, Australia
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48
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Kaczmarek D, Ristikankare J, Jankowska E. Does trans-spinal and local DC polarization affect presynaptic inhibition and post-activation depression? J Physiol 2017; 595:1743-1761. [PMID: 27891626 DOI: 10.1113/jp272902] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 11/15/2016] [Indexed: 12/25/2022] Open
Abstract
KEY POINTS Trans-spinal polarization was recently introduced as a means to improve deficient spinal functions. However, only a few attempts have been made to examine the mechanisms underlying DC actions. We have now examined the effects of DC on two spinal modulatory systems, presynaptic inhibition and post-activation depression, considering whether they might weaken exaggerated spinal reflexes and enhance excessively weakened ones. Direct current effects were evoked by using local intraspinal DC application (0.3-0.4 μA) in deeply anaesthetized rats and were compared with the effects of trans-spinal polarization (0.8-1.0 mA). Effects of local intraspinal DC were found to be polarity dependent, as locally applied cathodal polarization enhanced presynaptic inhibition and post-activation depression, whereas anodal polarization weakened them. In contrast, both cathodal and anodal trans-spinal polarization facilitated them. The results suggest some common DC-sensitive mechanisms of presynaptic inhibition and post-activation depression, because both were facilitated or depressed by DC in parallel. ABSTRACT Direct current (DC) polarization has been demonstrated to alleviate the effects of various deficits in the operation of the central nervous system. However, the effects of trans-spinal DC stimulation (tsDCS) have been investigated less extensively than the effects of transcranial DC stimulation, and their cellular mechanisms have not been elucidated. The main objectives of this study were, therefore, to extend our previous analysis of DC effects on the excitability of primary afferents and synaptic transmission by examining the effects of DC on two spinal modulatory feedback systems, presynaptic inhibition and post-activation depression, in an anaesthetized rat preparation. Other objectives were to compare the effects of locally and trans-spinally applied DC (locDC and tsDCS). Local polarization at the sites of terminal branching of afferent fibres was found to induce polarity-dependent actions on presynaptic inhibition and post-activation depression, as cathodal locDC enhanced them and anodal locDC depressed them. In contrast, tsDCS modulated presynaptic inhibition and post-activation depression in a polarity-independent fashion because both cathodal and anodal tsDCS facilitated them. The results show that the local presynaptic actions of DC might counteract both excessively strong and excessively weak monosynaptic actions of group Ia and cutaneous afferents. However, they indicate that trans-spinally applied DC might counteract the exaggerated spinal reflexes but have an adverse effect on pathologically weakened spinal activity by additional presynaptic weakening. The results are also relevant for the analysis of the basic properties of presynaptic inhibition and post-activation depression because they indicate that some common DC-sensitive mechanisms contribute to them.
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Affiliation(s)
- D Kaczmarek
- Department of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Sweden.,Department of Neurobiology, Poznań University of Physical Education, Poznań, Poland.,Department of Biochemistry, Poznań University of Physical Education, Poznań, Poland
| | - J Ristikankare
- Department of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Sweden
| | - E Jankowska
- Department of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Sweden
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Evidence-based guidelines on the therapeutic use of transcranial direct current stimulation (tDCS). Clin Neurophysiol 2016; 128:56-92. [PMID: 27866120 DOI: 10.1016/j.clinph.2016.10.087] [Citation(s) in RCA: 1017] [Impact Index Per Article: 127.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 10/18/2016] [Accepted: 10/20/2016] [Indexed: 12/19/2022]
Abstract
A group of European experts was commissioned by the European Chapter of the International Federation of Clinical Neurophysiology to gather knowledge about the state of the art of the therapeutic use of transcranial direct current stimulation (tDCS) from studies published up until September 2016, regarding pain, Parkinson's disease, other movement disorders, motor stroke, poststroke aphasia, multiple sclerosis, epilepsy, consciousness disorders, Alzheimer's disease, tinnitus, depression, schizophrenia, and craving/addiction. The evidence-based analysis included only studies based on repeated tDCS sessions with sham tDCS control procedure; 25 patients or more having received active treatment was required for Class I, while a lower number of 10-24 patients was accepted for Class II studies. Current evidence does not allow making any recommendation of Level A (definite efficacy) for any indication. Level B recommendation (probable efficacy) is proposed for: (i) anodal tDCS of the left primary motor cortex (M1) (with right orbitofrontal cathode) in fibromyalgia; (ii) anodal tDCS of the left dorsolateral prefrontal cortex (DLPFC) (with right orbitofrontal cathode) in major depressive episode without drug resistance; (iii) anodal tDCS of the right DLPFC (with left DLPFC cathode) in addiction/craving. Level C recommendation (possible efficacy) is proposed for anodal tDCS of the left M1 (or contralateral to pain side, with right orbitofrontal cathode) in chronic lower limb neuropathic pain secondary to spinal cord lesion. Conversely, Level B recommendation (probable inefficacy) is conferred on the absence of clinical effects of: (i) anodal tDCS of the left temporal cortex (with right orbitofrontal cathode) in tinnitus; (ii) anodal tDCS of the left DLPFC (with right orbitofrontal cathode) in drug-resistant major depressive episode. It remains to be clarified whether the probable or possible therapeutic effects of tDCS are clinically meaningful and how to optimally perform tDCS in a therapeutic setting. In addition, the easy management and low cost of tDCS devices allow at home use by the patient, but this might raise ethical and legal concerns with regard to potential misuse or overuse. We must be careful to avoid inappropriate applications of this technique by ensuring rigorous training of the professionals and education of the patients.
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50
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Paired Stimulation to Promote Lasting Augmentation of Corticospinal Circuits. Neural Plast 2016; 2016:7043767. [PMID: 27800189 PMCID: PMC5075312 DOI: 10.1155/2016/7043767] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 08/11/2016] [Indexed: 01/22/2023] Open
Abstract
After injury, electrical stimulation of the nervous system can augment plasticity of spared or latent circuits through focal modulation. Pairing stimulation of two parts of a spared circuit can target modulation more specifically to the intended circuit. We discuss 3 kinds of paired stimulation in the context of the corticospinal system, because of its importance in clinical neurorehabilitation. The first uses principles of Hebbian plasticity: by altering the stimulation timing of presynaptic neurons and their postsynaptic targets, synapse function can be modulated up or down. The second form uses synchronized presynaptic inputs onto a common synaptic target. We dub this a “convergent” mechanism, because stimuli have to converge on a common target with coordinated timing. The third form induces focal modulation by tonic excitation of one region (e.g., the spinal cord) during phasic stimulation of another (e.g., motor cortex). Additionally, endogenous neural activity may be paired with exogenous electrical stimulation. This review addresses what is known about paired stimulation of the corticospinal system of both humans and animal models, emphasizes how it qualitatively differs from single-site stimulation, and discusses the gaps in knowledge that must be addressed to maximize its use and efficacy in neurorehabilitation.
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