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Tanaka T, Isomura Y, Kobayashi K, Hanakawa T, Tanaka S, Honda M. Electrophysiological Effects of Transcranial Direct Current Stimulation on Neural Activity in the Rat Motor Cortex. Front Neurosci 2020; 14:495. [PMID: 32714126 PMCID: PMC7340144 DOI: 10.3389/fnins.2020.00495] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Accepted: 04/20/2020] [Indexed: 02/04/2023] Open
Abstract
Transcranial direct current stimulation (tDCS) is a non-invasive technique that modulates the neuronal membrane potential. We have previously documented a sustainable increase in extracellular dopamine levels in the rat striatum of cathodal tDCS, suggesting that cathodal tDCS enhances the neuronal excitability of the cortex. In the present study, we investigated changes in neuronal activity in the cerebral cortex induced by tDCS at the point beneath the stimulus electrode in anesthetized rats in vivo. Multiunit recordings were performed to examine changes in neuronal activity before and after the application of tDCS. In the cathodal tDCS group, multiunit activity (indicating the collective firing rate of recorded neuronal populations) increased in the cerebral cortex. Both anodal and cathodal tDCS increased the firing rate of isolated single units in the cerebral cortex. Significant differences in activity were observed immediately following stimulation and persisted for more than an hour after stimulation. The primary finding of this study was that both anodal and cathodal tDCS increased in vivo neuronal activity in the rat cerebral cortex underneath the stimulus electrode.
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Affiliation(s)
- Tomoko Tanaka
- Department of Brain Development and Neural Regeneration, Tokyo Metropolitan Institute of Medical Science, Setagaya, Japan.,Department of Information Medicine, National Institute of Neuroscience, National Centre of Neurology and Psychiatry, Kodaira, Japan
| | - Yoshikazu Isomura
- Physiology and Cell Biology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Bunkyo, Japan
| | - Kazuto Kobayashi
- Department of Molecular Genetics, Institute of Biomedical Sciences, Fukushima Medical University School of Medicine, Fukushima, Japan
| | - Takashi Hanakawa
- Department of Information Medicine, National Institute of Neuroscience, National Centre of Neurology and Psychiatry, Kodaira, Japan.,Department of Advanced Neuroimaging, Integrative Brain Imaging Centre, National Centre of Neurology and Psychiatry, Kodaira, Japan
| | - Satoshi Tanaka
- Laboratory of Psychology, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Manabu Honda
- Department of Information Medicine, National Institute of Neuroscience, National Centre of Neurology and Psychiatry, Kodaira, Japan
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2
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Bikson M, Brunoni AR, Charvet LE, Clark VP, Cohen LG, Deng ZD, Dmochowski J, Edwards DJ, Frohlich F, Kappenman ES, Lim KO, Loo C, Mantovani A, McMullen DP, Parra LC, Pearson M, Richardson JD, Rumsey JM, Sehatpour P, Sommers D, Unal G, Wassermann EM, Woods AJ, Lisanby SH. Rigor and reproducibility in research with transcranial electrical stimulation: An NIMH-sponsored workshop. Brain Stimul 2018; 11:465-480. [PMID: 29398575 PMCID: PMC5997279 DOI: 10.1016/j.brs.2017.12.008] [Citation(s) in RCA: 126] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 12/01/2017] [Accepted: 12/21/2017] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Neuropsychiatric disorders are a leading source of disability and require novel treatments that target mechanisms of disease. As such disorders are thought to result from aberrant neuronal circuit activity, neuromodulation approaches are of increasing interest given their potential for manipulating circuits directly. Low intensity transcranial electrical stimulation (tES) with direct currents (transcranial direct current stimulation, tDCS) or alternating currents (transcranial alternating current stimulation, tACS) represent novel, safe, well-tolerated, and relatively inexpensive putative treatment modalities. OBJECTIVE This report seeks to promote the science, technology and effective clinical applications of these modalities, identify research challenges, and suggest approaches for addressing these needs in order to achieve rigorous, reproducible findings that can advance clinical treatment. METHODS The National Institute of Mental Health (NIMH) convened a workshop in September 2016 that brought together experts in basic and human neuroscience, electrical stimulation biophysics and devices, and clinical trial methods to examine the physiological mechanisms underlying tDCS/tACS, technologies and technical strategies for optimizing stimulation protocols, and the state of the science with respect to therapeutic applications and trial designs. RESULTS Advances in understanding mechanisms, methodological and technological improvements (e.g., electronics, computational models to facilitate proper dosing), and improved clinical trial designs are poised to advance rigorous, reproducible therapeutic applications of these techniques. A number of challenges were identified and meeting participants made recommendations made to address them. CONCLUSIONS These recommendations align with requirements in NIMH funding opportunity announcements to, among other needs, define dosimetry, demonstrate dose/response relationships, implement rigorous blinded trial designs, employ computational modeling, and demonstrate target engagement when testing stimulation-based interventions for the treatment of mental disorders.
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Affiliation(s)
- Marom Bikson
- Department of Biomedical Engineering, The City College of the City University of New York, United States
| | - Andre R Brunoni
- Laboratory of Neurosciences (LIM-27), Department and Institute of Psychiatry, University of Sao Paulo, Sao Paulo, Brazil
| | - Leigh E Charvet
- Department of Neurology, New York University School of Medicine, New York, NY, United States
| | - Vincent P Clark
- Department of Psychology, University of New Mexico, Albuquerque, NM, United States
| | - Leonardo G Cohen
- Human Cortical Physiology and Neurorehabilitation Section, National Institute of Neurological Disorders and Stroke, Bethesda, MD, United States
| | - Zhi-De Deng
- Experimental Therapeutics and Pathophysiology Branch, National Institute of Mental Health, Bethesda, MD, United States
| | - Jacek Dmochowski
- Department of Biomedical Engineering, The City College of the City University of New York, United States
| | - Dylan J Edwards
- Non-invasive Brain Stimulation and Human Motor Control Laboratory, Burke Rehabilitation and Research, Burke-Cornell Medical Research Facility, White Plains, New York and School of Medicine and Health Sciences, Edith Cowan University, Perth, Australia
| | - Flavio Frohlich
- Department of Psychiatry, Cell Biology and Physiology, Biomedical Engineering, and Neurology, Carolina Center for Neurostimulation, University of North Carolina School of Medicine, Chapel Hill, NC, United States
| | - Emily S Kappenman
- Department of Psychology, San Diego State University, San Diego, CA, United States
| | - Kelvin O Lim
- Department of Psychiatry, University of Minnesota, Minneapolis Veterans Administration Health Care System, and Defense Veterans Brain Injury Center, Minneapolis, MN, United States
| | - Colleen Loo
- School of Psychiatry and Black Dog Institute, University of New South Wales, Sydney, Australia
| | - Antonio Mantovani
- Department of Physiology, Pharmacology and Neuroscience, City College of the City University of New York, New York, NY, United States
| | - David P McMullen
- Division of Translational Research, National Institute of Mental Health, Bethesda, MD, United States
| | - Lucas C Parra
- Department of Biomedical Engineering, The City College of the City University of New York, United States
| | - Michele Pearson
- Division of Translational Research, National Institute of Mental Health, Bethesda, MD, United States
| | - Jessica D Richardson
- Department of Speech and Hearing Sciences, University of New Mexico, Albuquerque, NM, United States
| | - Judith M Rumsey
- Division of Translational Research, National Institute of Mental Health, Bethesda, MD, United States.
| | - Pejman Sehatpour
- Department of Psychiatry, Columbia University, New York, NY, United States
| | - David Sommers
- Scientific Review Branch, National Institute of Mental Health, Bethesda, MD, United States
| | - Gozde Unal
- Department of Biomedical Engineering, The City College of the City University of New York, United States
| | - Eric M Wassermann
- Behavioral Neurology Unit, National Institute of Neurological Disorders and Stroke, Bethesda, MD, United States
| | - Adam J Woods
- Department of Clinical and Health Psychology, Center for Cognitive Aging and Memory, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
| | - Sarah H Lisanby
- Division of Translational Research, National Institute of Mental Health, Bethesda, MD, United States
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Giordano J, Bikson M, Kappenman ES, Clark VP, Coslett HB, Hamblin MR, Hamilton R, Jankord R, Kozumbo WJ, McKinley RA, Nitsche MA, Reilly JP, Richardson J, Wurzman R, Calabrese E. Mechanisms and Effects of Transcranial Direct Current Stimulation. Dose Response 2017; 15:1559325816685467. [PMID: 28210202 PMCID: PMC5302097 DOI: 10.1177/1559325816685467] [Citation(s) in RCA: 127] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The US Air Force Office of Scientific Research convened a meeting of researchers in the fields of neuroscience, psychology, engineering, and medicine to discuss most pressing issues facing ongoing research in the field of transcranial direct current stimulation (tDCS) and related techniques. In this study, we present opinions prepared by participants of the meeting, focusing on the most promising areas of research, immediate and future goals for the field, and the potential for hormesis theory to inform tDCS research. Scientific, medical, and ethical considerations support the ongoing testing of tDCS in healthy and clinical populations, provided best protocols are used to maximize safety. Notwithstanding the need for ongoing research, promising applications include enhancing vigilance/attention in healthy volunteers, which can accelerate training and support learning. Commonly, tDCS is used as an adjunct to training/rehabilitation tasks with the goal of leftward shift in the learning/treatment effect curves. Although trials are encouraging, elucidating the basic mechanisms of tDCS will accelerate validation and adoption. To this end, biomarkers (eg, clinical neuroimaging and findings from animal models) can support hypotheses linking neurobiological mechanisms and behavioral effects. Dosage can be optimized using computational models of current flow and understanding dose–response. Both biomarkers and dosimetry should guide individualized interventions with the goal of reducing variability. Insights from other applied energy domains, including ionizing radiation, transcranial magnetic stimulation, and low-level laser (light) therapy, can be prudently leveraged.
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Affiliation(s)
- James Giordano
- Department of Neurology and Biochemistry, Neuroethics Studies Program, Pellegrino Center for Clinical Bioethics, Georgetown University Medical Center, Washington, DC, USA
| | - Marom Bikson
- Biomedical Engineering, City College of New York, CUNY, New York, NY, USA
| | - Emily S Kappenman
- San Diego State University, Department of Psychology, San Diego, CA, USA
| | - Vincent P Clark
- Psychology Clinical Neuroscience Center, Department of Psychology, University of New Mexico, Albuquerque, NM, USA
| | - H Branch Coslett
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Michael R Hamblin
- Wellman Center for Photomedicine, Massachusetts General Hospital and Department of Dermatology, Harvard Medical School, Boston, MA, USA
| | - Roy Hamilton
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Ryan Jankord
- United States Air Force Research Laboratory, Wright-Patterson Air Force Base, OH, USA
| | | | - R Andrew McKinley
- United States Air Force Research Laboratory, Wright-Patterson Air Force Base, OH, USA
| | - Michael A Nitsche
- Department Psychology and Neurosciences, Leibniz Research Center for Working Environmental and Human Factors, Dortmund, Germany
| | | | - Jessica Richardson
- Department of Speech and Hearing Sciences, University of New Mexico, Albuquerque, NM, USA
| | - Rachel Wurzman
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Edward Calabrese
- Environmental Health Sciences, University of Massachusetts, Amherst, MA, USA
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Hunter MA, Coffman BA, Gasparovic C, Calhoun VD, Trumbo MC, Clark VP. Baseline effects of transcranial direct current stimulation on glutamatergic neurotransmission and large-scale network connectivity. Brain Res 2015; 1594:92-107. [PMID: 25312829 PMCID: PMC4358793 DOI: 10.1016/j.brainres.2014.09.066] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 09/11/2014] [Accepted: 09/28/2014] [Indexed: 01/01/2023]
Abstract
Transcranial direct current stimulation (tDCS) modulates glutamatergic neurotransmission and can be utilized as a novel treatment intervention for a multitude of populations. However, the exact mechanism by which tDCS modulates the brain׳s neural architecture, from the micro to macro scales, have yet to be investigated. Using a within-subjects design, resting-state functional magnetic resonance imaging (rs-fMRI) and proton magnetic resonance spectroscopy ((1)H MRS) were performed immediately before and after the administration of anodal tDCS over right parietal cortex. Group independent component analysis (ICA) was used to decompose fMRI scans into 75 brain networks, from which 12 resting-state networks were identified that had significant voxel-wise functional connectivity to anatomical regions of interest. (1)H MRS was used to obtain estimates of combined glutamate and glutamine (Glx) concentrations from bilateral intraparietal sulcus. Paired sample t-tests showed significantly increased Glx under the anodal electrode, but not in homologous regions of the contralateral hemisphere. Increases of within-network connectivity were observed within the superior parietal, inferior parietal, left frontal-parietal, salience and cerebellar intrinsic networks, and decreases in connectivity were observed in the anterior cingulate and the basal ganglia (p<0.05, FDR-corrected). Individual differences in Glx concentrations predicted network connectivity in most of these networks. The observed relationships between glutamatergic neurotransmission and network connectivity may be used to guide future tDCS protocols that aim to target and alter neuroplastic mechanisms in healthy individuals as well as those with psychiatric and neurologic disorders.
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Affiliation(s)
- Michael A Hunter
- Psychology Clinical Neuroscience Center, The University of New Mexico, Albuquerque, NM, USA; Department of Psychology, The University of New Mexico, NM, USA; The Mind Research Network, Albuquerque, NM, USA; Department of Psychiatry, The University of New Mexico School of Medicine, Albuquerque, NM, USA
| | - Brian A Coffman
- Psychology Clinical Neuroscience Center, The University of New Mexico, Albuquerque, NM, USA; Department of Psychology, The University of New Mexico, NM, USA; The Mind Research Network, Albuquerque, NM, USA
| | | | - Vince D Calhoun
- The Mind Research Network, Albuquerque, NM, USA; Department of Psychiatry, The University of New Mexico School of Medicine, Albuquerque, NM, USA; Department of Neurosciences, The University of New Mexico, Albuquerque, NM, USA; Department of Electrical and Computer Engineering, The University of New Mexico, Albuquerque, NM, USA
| | - Michael C Trumbo
- Psychology Clinical Neuroscience Center, The University of New Mexico, Albuquerque, NM, USA; Department of Psychology, The University of New Mexico, NM, USA; The Mind Research Network, Albuquerque, NM, USA
| | - Vincent P Clark
- Psychology Clinical Neuroscience Center, The University of New Mexico, Albuquerque, NM, USA; Department of Psychology, The University of New Mexico, NM, USA; The Mind Research Network, Albuquerque, NM, USA; Department of Neurosciences, The University of New Mexico, Albuquerque, NM, USA.
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Pirulli C, Fertonani A, Miniussi C. Is neural hyperpolarization by cathodal stimulation always detrimental at the behavioral level? Front Behav Neurosci 2014; 8:226. [PMID: 25018709 PMCID: PMC4073198 DOI: 10.3389/fnbeh.2014.00226] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 06/05/2014] [Indexed: 11/13/2022] Open
Abstract
Cathodal transcranial direct current stimulation (c-tDCS) is usually considered an inhibitory stimulation. From a physiological perspective, c-tDCS induces hyperpolarization at the neural level. However, from a behavioral perspective, c-tDCS application does not always result in performance deterioration. In this work, we investigated the role of several important stimulation parameters (i.e., timing, presence of pauses, duration, and intensity) in shaping the behavioral effects of c-tDCS over the primary visual cortex. In Experiment 1, we applied c-tDCS at two different times (before or during an orientation discrimination task). We also studied the effects of pauses during the stimulation. In Experiments 2 and 3, we compared different durations (9 vs. 22 min) and intensities (0.75 vs. 1.5 mA) of stimulation. c-tDCS applied before task execution induced an improvement of performance, highlighting the importance of the activation state of the cortex. However, this result depended on the duration and intensity of stimulation. We suggest that the application of c-tDCS induces depression of cortical activity over a specific stimulated area; but to keep reactivity within given limits, the brain react in order to restore the equilibrium and this might result in increased sensitivity in visual performance. This is a further example of how the nervous system dynamically maintains a condition that permits adequate performance in different environments.
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Affiliation(s)
- Cornelia Pirulli
- Cognitive Neuroscience Section, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli Brescia, Italy
| | - Anna Fertonani
- Cognitive Neuroscience Section, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli Brescia, Italy
| | - Carlo Miniussi
- Cognitive Neuroscience Section, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli Brescia, Italy ; Neuroscience Section, Department of Clinical and Experimental Sciences, University of Brescia Brescia, Italy
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Ellison A, Ball KL, Moseley P, Dowsett J, Smith DT, Weis S, Lane AR. Functional interaction between right parietal and bilateral frontal cortices during visual search tasks revealed using functional magnetic imaging and transcranial direct current stimulation. PLoS One 2014; 9:e93767. [PMID: 24705681 PMCID: PMC3976402 DOI: 10.1371/journal.pone.0093767] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 03/09/2014] [Indexed: 11/18/2022] Open
Abstract
The existence of a network of brain regions which are activated when one undertakes a difficult visual search task is well established. Two primary nodes on this network are right posterior parietal cortex (rPPC) and right frontal eye fields. Both have been shown to be involved in the orientation of attention, but the contingency that the activity of one of these areas has on the other is less clear. We sought to investigate this question by using transcranial direct current stimulation (tDCS) to selectively decrease activity in rPPC and then asking participants to perform a visual search task whilst undergoing functional magnetic resonance imaging. Comparison with a condition in which sham tDCS was applied revealed that cathodal tDCS over rPPC causes a selective bilateral decrease in frontal activity when performing a visual search task. This result demonstrates for the first time that premotor regions within the frontal lobe and rPPC are not only necessary to carry out a visual search task, but that they work together to bring about normal function.
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Affiliation(s)
- Amanda Ellison
- Department of Psychology, Durham University, Durham, United Kingdom
- * E-mail:
| | - Keira L. Ball
- Department of Psychology, Durham University, Durham, United Kingdom
| | - Peter Moseley
- Department of Psychology, Durham University, Durham, United Kingdom
| | - James Dowsett
- Department of Psychology, Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany
| | - Daniel T. Smith
- Department of Psychology, Durham University, Durham, United Kingdom
| | - Susanne Weis
- Department of Psychology, Durham University, Durham, United Kingdom
| | - Alison R. Lane
- Department of Psychology, Durham University, Durham, United Kingdom
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Amadi U, Ilie A, Johansen-Berg H, Stagg CJ. Polarity-specific effects of motor transcranial direct current stimulation on fMRI resting state networks. Neuroimage 2014; 88:155-61. [PMID: 24287440 PMCID: PMC3991849 DOI: 10.1016/j.neuroimage.2013.11.037] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 10/26/2013] [Accepted: 11/18/2013] [Indexed: 11/25/2022] Open
Abstract
Transcranial direct current stimulation (tDCS) has been used to modify motor performance in healthy and patient populations. However, our understanding of the large-scale neuroplastic changes that support such behavioural effects is limited. Here, we used both seed-based and independent component analyses (ICA) approaches to probe tDCS-induced modifications in resting state activity with the aim of establishing the effects of tDCS applied to the primary motor cortex (M1) on both motor and non-motor networks within the brain. Subjects participated in three separate sessions, during which resting fMRI scans were acquired before and after 10min of 1mA anodal, cathodal, or sham tDCS. Cathodal tDCS increased the inter-hemispheric coherence of resting fMRI signal between the left and right supplementary motor area (SMA), and between the left and right hand areas of M1. A similar trend was documented for the premotor cortex (PMC). Increased functional connectivity following cathodal tDCS was apparent within the ICA-generated motor and default mode networks. Additionally, the overall strength of the default mode network was increased. Neither anodal nor sham tDCS produced significant changes in resting state connectivity. This work indicates that cathodal tDCS to M1 affects the motor network at rest. In addition, the effects of cathodal tDCS on the default mode network support the hypothesis that diminished top-down control may contribute to the impaired motor performance induced by cathodal tDCS.
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Affiliation(s)
- Ugwechi Amadi
- Oxford Centre for Functional MRI of the Brain (FMRIB), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Andrei Ilie
- Oxford Centre for Functional MRI of the Brain (FMRIB), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK; Department of Pharmacology, University of Oxford, Oxford, UK
| | - Heidi Johansen-Berg
- Oxford Centre for Functional MRI of the Brain (FMRIB), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Charlotte Jane Stagg
- Oxford Centre for Functional MRI of the Brain (FMRIB), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
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Hunter MA, Coffman BA, Trumbo MC, Clark VP. Tracking the neuroplastic changes associated with transcranial direct current stimulation: a push for multimodal imaging. Front Hum Neurosci 2013; 7:495. [PMID: 23986681 PMCID: PMC3753560 DOI: 10.3389/fnhum.2013.00495] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 08/04/2013] [Indexed: 11/15/2022] Open
Affiliation(s)
- Michael A Hunter
- Psychology Clinical Neuroscience Center, The University of New Mexico Albuquerque, NM, USA ; Department of Psychology, The University of New Mexico Albuquerque, NM, USA ; Department of Psychiatry, The University of New Mexico School of Medicine Albuquerque, NM, USA ; The Mind Research Network and Lovelace Biomedical and Environmental Research Institute Albuquerque, NM, USA ; Psychiatry Research, New Mexico Raymond G. Murphy VA Healthcare System Albuquerque, NM, USA
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