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Frontal EEG Asymmetry as a Promising Marker of Depression Vulnerability: Summary and Methodological Considerations. Curr Opin Psychol 2015; 4:93-97. [PMID: 26462291 DOI: 10.1016/j.copsyc.2014.12.017] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Frontal EEG asymmetry is a promising neurophysiological marker of depression risk. It predicts emotional response and negative affect hours to years later. Yet, inconsistencies in the literature may be due to differing methodological approaches between research groups. Within the past two years, a number of studies have shown this line of research may be strengthened by augmenting resting assessments with emotionally evocative tasks, utilizing optimal recording montages, and taking an integrative neuroscience approach that links frontal asymmetry to other indices of neural function. This review will focus on recent work in frontal asymmetry and depression with a particular focus on promising future directions and methodological considerations that may increase consistency between research groups.
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202
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Cosmo C, Ferreira C, Miranda JGV, do Rosário RS, Baptista AF, Montoya P, de Sena EP. Spreading Effect of tDCS in Individuals with Attention-Deficit/Hyperactivity Disorder as Shown by Functional Cortical Networks: A Randomized, Double-Blind, Sham-Controlled Trial. Front Psychiatry 2015; 6:111. [PMID: 26300790 PMCID: PMC4524049 DOI: 10.3389/fpsyt.2015.00111] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 07/20/2015] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Transcranial direct current stimulation (tDCS) is known to modulate spontaneous neural network excitability. The cognitive improvement observed in previous trials raises the potential of this technique as a possible therapeutic tool for use in attention-deficit/hyperactivity disorder (ADHD) population. However, to explore the potential of this technique as a treatment approach, the functional parameters of brain connectivity and the extent of its effects need to be more fully investigated. OBJECTIVE The aim of this study was to investigate a functional cortical network (FCN) model based on electroencephalographic activity for studying the dynamic patterns of brain connectivity modulated by tDCS and the distribution of its effects in individuals with ADHD. METHODS Sixty ADHD patients participated in a parallel, randomized, double-blind, sham-controlled trial. Individuals underwent a single session of sham or anodal tDCS at 1 mA of current intensity over the left dorsolateral prefrontal cortex for 20 min. The acute effects of stimulation on brain connectivity were assessed using the FCN model based on electroencephalography activity. RESULTS Comparing the weighted node degree within groups prior to and following the intervention, a statistically significant difference was found in the electrodes located on the target and correlated areas in the active group (p < 0.05), while no statistically significant results were found in the sham group (p ≥ 0.05; paired-sample Wilcoxon signed-rank test). CONCLUSION Anodal tDCS increased functional brain connectivity in individuals with ADHD compared to data recorded in the baseline resting state. In addition, although some studies have suggested that the effects of tDCS are selective, the present findings show that its modulatory activity spreads. Further studies need to be performed to investigate the dynamic patterns and physiological mechanisms underlying the modulatory effects of tDCS. TRIAL REGISTRATION ClinicalTrials.gov NCT01968512.
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Affiliation(s)
- Camila Cosmo
- Postgraduate Program, Interactive Process of Organs and Systems, Federal University of Bahia , Salvador , Brazil ; Neuromodulation Center, Spaulding Rehabilitation Hospital, Harvard Medical School , Boston, MA , USA ; Bahia State Department of Health (SESAB) , Salvador , Brazil ; Functional Electrostimulation Laboratory, Biomorphology Department, Federal University of Bahia , Salvador , Brazil
| | - Cândida Ferreira
- Institute of Physics, Federal University of Bahia , Salvador , Brazil
| | | | | | - Abrahão Fontes Baptista
- Functional Electrostimulation Laboratory, Biomorphology Department, Federal University of Bahia , Salvador , Brazil ; Postgraduate Program in Medicine and Human Health, School of Medicine, Federal University of Bahia , Salvador , Brazil
| | - Pedro Montoya
- Research Institute in Health Sciences (IUNICS-IdisPa), University of the Balearic Islands , Palma , Spain
| | - Eduardo Pondé de Sena
- Postgraduate Program, Interactive Process of Organs and Systems, Federal University of Bahia , Salvador , Brazil
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203
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Dhaliwal SK, Meek BP, Modirrousta MM. Non-Invasive Brain Stimulation for the Treatment of Symptoms Following Traumatic Brain Injury. Front Psychiatry 2015; 6:119. [PMID: 26379560 PMCID: PMC4549551 DOI: 10.3389/fpsyt.2015.00119] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 08/10/2015] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Traumatic brain injury (TBI) is a common cause of physical, psychological, and cognitive impairment, but many current treatments for TBI are ineffective or produce adverse side effects. Non-invasive methods of brain stimulation could help ameliorate some common trauma-induced symptoms. OBJECTIVE This review summarizes instances in which repetitive Transcranial Magnetic Stimulation (rTMS) and transcranial Direct Current Stimulation (tDCS) have been used to treat symptoms following a TBI. A subsequent discussion attempts to determine the value of these methods in light of their potential risks. METHODS The research databases of PubMed/MEDLINE and PsycINFO were electronically searched using terms relevant to the use of rTMS and tDCS as a tool to decrease symptoms in the context of rehabilitation post-TBI. RESULTS Eight case-studies and four multi-subject reports using rTMS and six multi--subject studies using tDCS were found. Two instances of seizure are discussed. CONCLUSION There is evidence that rTMS can be an effective treatment option for some post-TBI symptoms, such as depression, tinnitus, and neglect. Although the safety of this method remains uncertain, the use of rTMS in cases of mild TBI without obvious structural damage may be justified. Evidence on the effectiveness of tDCS is mixed, highlighting the need for additional investigations.
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Affiliation(s)
| | - Benjamin P Meek
- Department of Psychiatry, University of Manitoba , Winnipeg, MB , Canada
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204
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Fröhlich F, Sellers KK, Cordle AL. Targeting the neurophysiology of cognitive systems with transcranial alternating current stimulation. Expert Rev Neurother 2014; 15:145-67. [PMID: 25547149 DOI: 10.1586/14737175.2015.992782] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cognitive impairment represents one of the most debilitating and most difficult symptom to treat of many psychiatric illnesses. Human neurophysiology studies have suggested that specific pathologies of cortical network activity correlate with cognitive impairment. However, we lack demonstration of causal relationships between specific network activity patterns and cognitive capabilities and treatment modalities that directly target impaired network dynamics of cognition. Transcranial alternating current stimulation (tACS), a novel non-invasive brain stimulation approach, may provide a crucial tool to tackle these challenges. Here, we propose that tACS can be used to elucidate the causal role of cortical synchronization in cognition and, eventually, to enhance pathologically weakened synchrony that may underlie cognitive deficits. To accelerate such development of tACS as a treatment for cognitive deficits, we discuss studies on tACS and cognition performed in healthy participants, according to the Research Domain Criteria of the National Institute of Mental Health.
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Affiliation(s)
- Flavio Fröhlich
- Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill NC 27599, USA
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205
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Woods AJ, Bryant V, Sacchetti D, Gervits F, Hamilton R. Effects of Electrode Drift in Transcranial Direct Current Stimulation. Brain Stimul 2014; 8:515-9. [PMID: 25583653 DOI: 10.1016/j.brs.2014.12.007] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Revised: 12/19/2014] [Accepted: 12/20/2014] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Conventional transcranial direct current stimulation (tDCS) methods involve application of weak electrical current through electrodes encased in saline-soaked sponges affixed to the head using elastic straps. In the absence of careful preparation, electrodes can drift from their original location over the course of a tDCS session. OBJECTIVE The current paper investigates the influence of electrode drift on distribution of electric fields generated by conventional tDCS. METHODS MRI-derived finite element models of electric fields produced by tDCS were used to investigate the influence of incremental drift in electrodes for two of the most common electrode montages used in the literature: M1/SO (motor to contralateral supraorbital) and F3/F4 (bilateral frontal). Based on these models, we extracted predicted current intensity from 20 representative structures in the brain. RESULTS Results from separate RM-ANOVAs for M1/SO and F3/F4 montages demonstrated that 5% incremental drift in electrode position significantly changed the distribution of current delivered by tDCS to the human brain (F's > 8.6, P's < 0.001). Pairwise comparisons demonstrated that as little as 5% drift was able to produce significant differences in current intensity in structures distributed across the brain (P's < 0.03). CONCLUSIONS Drift in electrode position during a session of tDCS produces significant alteration in the intensity of stimulation delivered to the brain. Elimination of this source of variability will facilitate replication and interpretation of tDCS findings. Furthermore, measurement and statistically accounting for drift may prove important for better characterizing the effects of tDCS on the human brain and behavior.
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Affiliation(s)
- Adam J Woods
- Cognitive Aging and Memory Clinical Translational Research Program, Institute on Aging, Department of Aging and Geriatric Research, University of Florida, USA.
| | - Vaughn Bryant
- Cognitive Aging and Memory Clinical Translational Research Program, Institute on Aging, Department of Aging and Geriatric Research, University of Florida, USA
| | - Daniela Sacchetti
- Center for Cognitive Neuroscience, Laboratory for Cognition and Neural Stimulation, Department of Neurology, University of Pennsylvania, USA
| | - Felix Gervits
- Center for Cognitive Neuroscience, Laboratory for Cognition and Neural Stimulation, Department of Neurology, University of Pennsylvania, USA
| | - Roy Hamilton
- Center for Cognitive Neuroscience, Laboratory for Cognition and Neural Stimulation, Department of Neurology, University of Pennsylvania, USA
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Roh T, Song K, Cho H, Shin D, Yoo HJ. A wearable neuro-feedback system with EEG-based mental status monitoring and transcranial electrical stimulation. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2014; 8:755-764. [PMID: 25585425 DOI: 10.1109/tbcas.2014.2384017] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A wearable neuro-feedback system is proposed with a low-power neuro-feedback SoC (NFS), which supports mental status monitoring with encephalography (EEG) and transcranial electrical stimulation (tES) for neuro-modulation. Self-configured independent component analysis (ICA) is implemented to accelerate source separation at low power. Moreover, an embedded support vector machine (SVM) enables online source classification, configuring the ICA accelerator adaptively depending on the types of the decomposed components. Owing to the hardwired accelerating functions, the NFS dissipates only 4.45 mW to yield 16 independent components. For non-invasive neuro-modulation, tES stimulation up to 2 mA is implemented on the SoC. The NFS is fabricated in 130-nm CMOS technology.
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Patient-conducted anodal transcranial direct current stimulation of the motor cortex alleviates pain in trigeminal neuralgia. J Headache Pain 2014; 15:78. [PMID: 25424567 PMCID: PMC4256974 DOI: 10.1186/1129-2377-15-78] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Accepted: 11/04/2014] [Indexed: 11/15/2022] Open
Abstract
Background Transcranial direct current stimulation (tDCS) of the primary motor cortex has been shown to modulate pain and trigeminal nociceptive processing. Methods Ten patients with classical trigeminal neuralgia (TN) were stimulated daily for 20 minutes over two weeks using anodal (1 mA) or sham tDCS over the primary motor cortex (M1) in a randomized double-blind cross-over design. Primary outcome variable was pain intensity on a verbal rating scale (VRS 0–10). VRS and attack frequency were assessed for one month before, during and after tDCS. The impact on trigeminal pain processing was assessed with pain-related evoked potentials (PREP) and the nociceptive blink reflex (nBR) following electrical stimulation on both sides of the forehead before and after tDCS. Results Anodal tDCS reduced pain intensity significantly after two weeks of treatment. The attack frequency reduction was not significant. PREP showed an increased N2 latency and decreased peak-to-peak amplitude after anodal tDCS. No severe adverse events were reported. Conclusion Anodal tDCS over two weeks ameliorates intensity of pain in TN. It may become a valuable treatment option for patients unresponsive to conventional treatment.
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208
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A randomized controlled trial of targeted prefrontal cortex modulation with tDCS in patients with alcohol dependence. Int J Neuropsychopharmacol 2014; 17:1793-803. [PMID: 25008145 DOI: 10.1017/s1461145714000984] [Citation(s) in RCA: 119] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Preliminary small studies have shown that transcranial direct current stimulation (tDCS) reduces craving in alcoholic subjects. It is unclear whether tDCS also leads to changes in clinically meaningful outcomes for alcohol dependence in a properly powered phase II randomized clinical trial. We aimed to investigate whether repetitive tDCS changes the risk of alcohol use relapse in severe alcoholics from outpatient services. Thirty-five subjects were randomized to receive active bilateral [left cathodal/right anodal over the dorsolateral prefrontal cortex (dlPFC)] repetitive (five consecutive days) tDCS (2 mA, 35 cm2, two times daily stimulation for 13 min with a 20-min interval) or sham-tDCS. There were two dropouts before treatment. From 33 alcoholic subjects, 17 (mean age 45.5±8.9 s.d., 16 males) were randomized to sham and 16 (44±7.8 s.d., 16 males) to real tDCS treatment. By the end of the six months of follow-up, two subjects treated with sham (11.8%) and eight treated with real tDCS (50%) were still alcohol-abstinent [p=0.02, Long-rank (Mantel-Cox) Test, HR=0.35 (95% CI, 0.14-0.85)]. No differences with regard to changes on scores of craving, frontal function, global mental status, depressive or anxiety symptoms were observed between groups. However, subjects from the tDCS group improved with regard to their overall perception of quality of life (p=0.02), and increased their scores in the environment domain (p=0.04) after treatment. Bilateral tDCS over dlPFC reduces relapse probability in severe alcoholic subjects and results in improved perception of quality of life.
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209
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The role of superior temporal sulcus in the control of irrelevant emotional face processing: A transcranial direct current stimulation study. Neuropsychologia 2014; 64:124-33. [DOI: 10.1016/j.neuropsychologia.2014.09.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 08/26/2014] [Accepted: 09/07/2014] [Indexed: 11/20/2022]
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210
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Transcranial direct current stimulation (tDCS) for auditory verbal hallucinations in schizophrenia during pregnancy: a case report. Brain Stimul 2014; 8:163-4. [PMID: 25468071 DOI: 10.1016/j.brs.2014.10.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 10/15/2014] [Accepted: 10/22/2014] [Indexed: 11/24/2022] Open
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State dependent effect of transcranial direct current stimulation (tDCS) on methamphetamine craving. Int J Neuropsychopharmacol 2014; 17:1591-8. [PMID: 24825251 DOI: 10.1017/s1461145714000686] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Transcranial direct current stimulation (tDCS) has been shown to modulate subjective craving ratings in drug dependents by modification of cortical excitability in dorsolateral prefrontal cortex (DLPFC). Given the mechanism of craving in methamphetamine (meth) users, we aimed to test whether tDCS of DLPFC could also alter self-reported craving in abstinent meth users while being exposed to meth cues. In this double-blinded, crossover, sham-controlled study, thirty two right-handed abstinent male meth users were recruited. We applied 20 min 'anodal' tDCS (2 mA) or 'sham' tDCS over right DLPFC in a random sequence while subjects performed a computerized cue-induced craving task (CICT) starting after 10 min of stimulation. Immediate craving was assessed before the stimulation, after 10 min of tDCS, and after tDCS termination by visual analog scale (VAS) of 0 to 100. Anodal tDCS of rDLPFC altered craving ratings significantly. We found a significant reduction of craving at rest in real tDCS relative to the sham condition (p = 0.016) after 10 min of stimulation. On the other hand, cue-induced VAS craving was rated significantly higher in the real condition in comparison with sham stimulation (p = 0.012). Our findings showed a state dependent effect of tDCS: while active prefrontal tDCS acutely reduced craving at rest in the abstinent meth users, it increased craving during meth-related cue exposure. These findings reflect the important role of the prefrontal cortex in both cue saliency evaluation and urge to meth consumption.
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212
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Vigod S, Dennis CL, Daskalakis Z, Murphy K, Ray J, Oberlander T, Somerton S, Hussain-Shamsy N, Blumberger D. Transcranial direct current stimulation (tDCS) for treatment of major depression during pregnancy: study protocol for a pilot randomized controlled trial. Trials 2014; 15:366. [PMID: 25234606 PMCID: PMC4177439 DOI: 10.1186/1745-6215-15-366] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 09/10/2014] [Indexed: 11/15/2022] Open
Abstract
Background Women with depression in pregnancy are faced with difficult treatment decisions. Untreated, antenatal depression has serious negative implications for mothers and children. While antidepressant drug treatment is likely to improve depressive symptoms, it crosses the placenta and may pose risks to the unborn child. Transcranial direct current stimulation is a focal brain stimulation treatment that improves depressive symptoms within 3 weeks of treatment by inducing changes to brain areas involved in depression, without impacting any other brain areas, and without inducing changes to heart rate, blood pressure or core body temperature. The localized nature of transcranial direct current stimulation makes it an ideal therapeutic approach for treating depression during pregnancy, although it has never previously been evaluated in this population. Methods/design We describe a pilot randomized controlled trial of transcranial direct current stimulation among women with depression in pregnancy to assess the feasibility of a larger, multicentre efficacy study. Women over 18 years of age and between 14 and 32 weeks gestation can be enrolled in the study provided they meet diagnostic criteria for a major depressive episode of at least moderate severity and have been offered but refused antidepressant medication. Participants are randomized to receive active transcranial direct current stimulation or a sham condition that is administered in 15 30-minute treatments over three weeks. Women sit upright during treatment and receive obstetrical monitoring prior to, during and after each treatment session. Depressive symptoms, treatment acceptability, and pregnancy outcomes are assessed at baseline (prior to randomization), at the end of each treatment week, every four weeks post-treatment until delivery, and at 4 and 12 weeks postpartum. Discussion Transcranial direct current stimulation is a novel therapeutic option for treating depression during pregnancy. This protocol allows for assessment of the feasibility of, acceptability of and adherence with a clinical trial protocol to administer this treatment to pregnant women with moderate to severe depression. Results from this pilot study will guide the development of a larger multicentre trial to definitively test the efficacy and safety of transcranial direct current stimulation for pregnant women with depression. Trial registration Clinical Trials Gov NCT02116127.
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Affiliation(s)
- Simone Vigod
- Women's College Hospital and Research Institute, 76 Grenville Street, Toronto, ON M5S 1B1, Canada.
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Manepalli J, Sapkota N. Neuromodulation Therapies in the Elderly Depressed Patient. CURRENT GERIATRICS REPORTS 2014. [DOI: 10.1007/s13670-014-0098-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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214
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Does anodal transcranial direct current stimulation modulate sensory perception and pain? A meta-analysis study. Clin Neurophysiol 2014; 125:1847-58. [DOI: 10.1016/j.clinph.2014.01.020] [Citation(s) in RCA: 103] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 01/01/2014] [Accepted: 01/09/2014] [Indexed: 11/21/2022]
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215
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Romero Lauro LJ, Rosanova M, Mattavelli G, Convento S, Pisoni A, Opitz A, Bolognini N, Vallar G. TDCS increases cortical excitability: Direct evidence from TMS–EEG. Cortex 2014; 58:99-111. [DOI: 10.1016/j.cortex.2014.05.003] [Citation(s) in RCA: 129] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Revised: 01/13/2014] [Accepted: 05/13/2014] [Indexed: 10/25/2022]
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216
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Luft CDB, Pereda E, Banissy MJ, Bhattacharya J. Best of both worlds: promise of combining brain stimulation and brain connectome. Front Syst Neurosci 2014; 8:132. [PMID: 25126060 PMCID: PMC4115621 DOI: 10.3389/fnsys.2014.00132] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2014] [Accepted: 07/07/2014] [Indexed: 12/12/2022] Open
Abstract
Transcranial current brain stimulation (tCS) is becoming increasingly popular as a non-pharmacological non-invasive neuromodulatory method that alters cortical excitability by applying weak electrical currents to the scalp via a pair of electrodes. Most applications of this technique have focused on enhancing motor and learning skills, as well as a therapeutic agent in neurological and psychiatric disorders. In these applications, similarly to lesion studies, tCS was used to provide a causal link between a function or behavior and a specific brain region (e.g., primary motor cortex). Nonetheless, complex cognitive functions are known to rely on functionally connected multitude of brain regions with dynamically changing patterns of information flow rather than on isolated areas, which are most commonly targeted in typical tCS experiments. In this review article, we argue in favor of combining tCS method with other neuroimaging techniques (e.g., fMRI, EEG) and by employing state-of-the-art connectivity data analysis techniques (e.g., graph theory) to obtain a deeper understanding of the underlying spatiotemporal dynamics of functional connectivity patterns and cognitive performance. Finally, we discuss the possibilities of using these combined techniques to investigate the neural correlates of human creativity and to enhance creativity.
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Affiliation(s)
| | - Ernesto Pereda
- Lab. of Electrical Engineering and Bioengineering, Department of Industrial Engineering, Institute of Biomedical Technology, University of La Laguna Tenerife, Spain
| | - Michael J Banissy
- Department of Psychology, Goldsmiths, University of London London, UK
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217
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Prehn-Kristensen A, Munz M, Göder R, Wilhelm I, Korr K, Vahl W, Wiesner CD, Baving L. Transcranial oscillatory direct current stimulation during sleep improves declarative memory consolidation in children with attention-deficit/hyperactivity disorder to a level comparable to healthy controls. Brain Stimul 2014; 7:793-9. [PMID: 25153776 DOI: 10.1016/j.brs.2014.07.036] [Citation(s) in RCA: 107] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 07/17/2014] [Accepted: 07/17/2014] [Indexed: 10/25/2022] Open
Abstract
BACKGROUND Slow oscillations (<1 Hz) during slow wave sleep (SWS) promote the consolidation of declarative memory. Children with attention-deficit/hyperactivity disorder (ADHD) have been shown to display deficits in sleep-dependent consolidation of declarative memory supposedly due to dysfunctional slow brain rhythms during SWS. OBJECTIVE Using transcranial oscillating direct current stimulation (toDCS) at 0.75 Hz, we investigated whether an externally triggered increase in slow oscillations during early SWS elevates memory performance in children with ADHD. METHODS 12 children with ADHD underwent a toDCS and a sham condition in a double-blind crossover study design conducted in a sleep laboratory. Memory was tested using a 2D object-location task. In addition, 12 healthy children performed the same memory task in their home environment. RESULTS Stimulation enhanced slow oscillation power in children with ADHD and boosted memory performance to the same level as in healthy children. CONCLUSION These data indicate that increasing slow oscillation power during sleep by toDCS can alleviate declarative memory deficits in children with ADHD.
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Affiliation(s)
- Alexander Prehn-Kristensen
- Department of Child and Adolescent Psychiatry and Psychotherapy, Center for Integrative Psychiatry, School of Medicine, Christian-Albrechts-University Kiel, Germany.
| | - Manuel Munz
- Department of Child and Adolescent Psychiatry and Psychotherapy, Center for Integrative Psychiatry, School of Medicine, Christian-Albrechts-University Kiel, Germany
| | - Robert Göder
- Department of Psychiatry and Psychotherapy, Center for Integrative Psychiatry, School of Medicine, Christian-Albrechts-University Kiel, Germany
| | - Ines Wilhelm
- Institute of Medical Psychology and Behavioural Neurobiology, University of Tübingen, Germany; Child Development Center, University Children's Hospital Zürich, Switzerland
| | - Katharina Korr
- Department of Child and Adolescent Psychiatry and Psychotherapy, Center for Integrative Psychiatry, School of Medicine, Christian-Albrechts-University Kiel, Germany
| | - Wiebke Vahl
- Department of Child and Adolescent Psychiatry and Psychotherapy, Center for Integrative Psychiatry, School of Medicine, Christian-Albrechts-University Kiel, Germany
| | - Christian D Wiesner
- Department of Child and Adolescent Psychiatry and Psychotherapy, Center for Integrative Psychiatry, School of Medicine, Christian-Albrechts-University Kiel, Germany
| | - Lioba Baving
- Department of Child and Adolescent Psychiatry and Psychotherapy, Center for Integrative Psychiatry, School of Medicine, Christian-Albrechts-University Kiel, Germany
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Guleyupoglu B, Febles N, Minhas P, Hahn C, Bikson M. Reduced discomfort during high-definition transcutaneous stimulation using 6% benzocaine. FRONTIERS IN NEUROENGINEERING 2014; 7:28. [PMID: 25071548 PMCID: PMC4093654 DOI: 10.3389/fneng.2014.00028] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Accepted: 06/25/2014] [Indexed: 12/19/2022]
Abstract
Background: High-Definition transcranial Direct Current Stimulation (HD-tDCS) allows for non-invasive neuromodulation using an array of compact (approximately 1 cm2 contact area) “High-Definition” (HD) electrodes, as compared to conventional tDCS (which uses two large pads that are approximately 35 cm2). In a previous transcutaneous study, we developed and validated designs for HD electrodes that reduce discomfort over >20 min session with 2 mA electrode current. Objective: The purpose of this study was to investigate the use of a chemical pretreatment with 6% benzocaine (topical numbing agent) to further reduce subjective discomfort during transcutaneous stimulation and to allow for better sham controlled studies. Methods: Pre-treatment with 6% benzocaine was compared with control (no pretreatment) for 22 min 2 mA of stimulation, with either CCNY-4 or Lectron II electroconductive gel, for both cathodal and anodal transcutaneous (forearm) stimulation (eight different combinations). Results: Results show that for all conditions and polarities tested, stimulation with HD electrodes is safe and well tolerated and that pretreatment further reduced subjective discomfort. Conclusion: Pretreatment with a mild analgesic reduces discomfort during HD-tDCS.
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Affiliation(s)
- Berkan Guleyupoglu
- Department of Biomedical Engineering, Neural Engineering Laboratory, The City College of the City University of New York New York, NY, USA
| | - Nicole Febles
- Department of Biomedical Engineering, Neural Engineering Laboratory, The City College of the City University of New York New York, NY, USA
| | - Preet Minhas
- Department of Biomedical Engineering, Neural Engineering Laboratory, The City College of the City University of New York New York, NY, USA
| | - Christoph Hahn
- Biomedical Engineering, University of Applied Sciences Hamburg Hamburg, Germany
| | - Marom Bikson
- Department of Biomedical Engineering, Neural Engineering Laboratory, The City College of the City University of New York New York, NY, USA
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Han CH, Song H, Kang YG, Kim BM, Im CH. Hemodynamic responses in rat brain during transcranial direct current stimulation: a functional near-infrared spectroscopy study. BIOMEDICAL OPTICS EXPRESS 2014; 5:1812-21. [PMID: 24940542 PMCID: PMC4052913 DOI: 10.1364/boe.5.001812] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Revised: 04/18/2014] [Accepted: 04/21/2014] [Indexed: 05/22/2023]
Abstract
In the present study, we monitored hemodynamic responses in rat brains during transcranial direct current stimulation (tDCS) using functional near-infrared spectroscopy (fNIRS). Seven rats received transcranial anodal stimulation with 200 μA direct current (DC) on their right barrel cortex for 10 min. The concentration changes of oxygenated hemoglobin (oxy-Hb) were continuously monitored during stimulation (10 min) and after stimulation (20 min). The trend of hemodynamic response changes was modeled using linear regression, and the relationship between incremental and decremental rates of oxy-Hb was investigated by correlation analysis. Our results showed that the oxy-Hb concentration was almost linearly increased and decreased during and after stimulation, respectively. In addition, a significant negative correlation (p < 0.05) was found between the rate of increase of oxy-Hb during stimulation and the rate of decrease of oxy-Hb after stimulation, indicating that the recovery time after tDCS may not depend on the total amount of hemodynamic changes in the stimulated brain area. Our results also demonstrated considerable individual variability in the rate of change of hemodynamic responses even with the same direct current dose to identical brain regions. This suggests that individual differences in tDCS after-effects may originate from intrinsic differences in the speed of DC stimulation "uptake" rather than differences in the total capacity of DC uptake, and thus the stimulation parameters may need to be customized for each individual in order to maximize tDCS after-effects.
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Affiliation(s)
- Chang-Hee Han
- Department of Biomedical Engineering, Hanyang University, Wangsimni-ro, Seongdong-gu, Seoul, 133-791, South Korea
- contributed equally
| | - Hyuna Song
- Department of Biomedical Engineering, Korea University, Jeongneung 3-dong, Seongbuk-ku, Seoul, 136-703, South Korea
- contributed equally
| | - Yong-Guk Kang
- Department of Biomedical Engineering, Korea University, Jeongneung 3-dong, Seongbuk-ku, Seoul, 136-703, South Korea
| | - Beop-Min Kim
- Department of Biomedical Engineering, Korea University, Jeongneung 3-dong, Seongbuk-ku, Seoul, 136-703, South Korea
| | - Chang-Hwan Im
- Department of Biomedical Engineering, Hanyang University, Wangsimni-ro, Seongdong-gu, Seoul, 133-791, South Korea
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220
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McIntire LK, McKinley RA, Goodyear C, Nelson J. A comparison of the effects of transcranial direct current stimulation and caffeine on vigilance and cognitive performance during extended wakefulness. Brain Stimul 2014; 7:499-507. [PMID: 25047826 DOI: 10.1016/j.brs.2014.04.008] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 04/24/2014] [Accepted: 04/29/2014] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND Sleep deprivation from extended duty hours is a common complaint for many occupations. Caffeine is one of the most common countermeasures used to combat fatigue. However, the benefits of caffeine decline over time and with chronic use. OBJECTIVE Our objective was to evaluate the efficacy of anodal transcranial direct current stimulation (tDCS) applied to the pre-frontal cortex at 2 mA for 30 min to remediate the effects of sleep deprivation and to compare the behavioral effects of tDCS with those of caffeine. METHODS Three groups of 10 participants each received either active tDCS with placebo gum, caffeine gum with sham tDCS, or sham tDCS with placebo gum during 30 h of extended wakefulness. RESULTS Our results show that tDCS prevented a decrement in vigilance and led to better subjective ratings for fatigue, drowsiness, energy, and composite mood compared to caffeine and control in sleep-deprived individuals. Both the tDCS and caffeine produced similar improvements in latencies on a short-term memory task and faster reaction times in a psychomotor task when compared to the placebo group. Interestingly, changes in accuracy for the tDCS group were not correlated to changes in mood; whereas, there was a relationship for the caffeine and sham groups. CONCLUSION Our data suggest that tDCS could be a useful fatigue countermeasure and may be more beneficial than caffeine since boosts in performance and mood last several hours.
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Affiliation(s)
| | - R Andy McKinley
- 711th HPW, Applied Neuroscience Branch, 2510 Fifth Street, Bldg 840, USA.
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221
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Shahid SS, Bikson M, Salman H, Wen P, Ahfock T. The value and cost of complexity in predictive modelling: role of tissue anisotropic conductivity and fibre tracts in neuromodulation. J Neural Eng 2014; 11:036002. [PMID: 24737098 DOI: 10.1088/1741-2560/11/3/036002] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVES Computational methods are increasingly used to optimize transcranial direct current stimulation (tDCS) dose strategies and yet complexities of existing approaches limit their clinical access. Since predictive modelling indicates the relevance of subject/pathology based data and hence the need for subject specific modelling, the incremental clinical value of increasingly complex modelling methods must be balanced against the computational and clinical time and costs. For example, the incorporation of multiple tissue layers and measured diffusion tensor (DTI) based conductivity estimates increase model precision but at the cost of clinical and computational resources. Costs related to such complexities aggregate when considering individual optimization and the myriad of potential montages. Here, rather than considering if additional details change current-flow prediction, we consider when added complexities influence clinical decisions. APPROACH Towards developing quantitative and qualitative metrics of value/cost associated with computational model complexity, we considered field distributions generated by two 4 × 1 high-definition montages (m1 = 4 × 1 HD montage with anode at C3 and m2 = 4 × 1 HD montage with anode at C1) and a single conventional (m3 = C3-Fp2) tDCS electrode montage. We evaluated statistical methods, including residual error (RE) and relative difference measure (RDM), to consider the clinical impact and utility of increased complexities, namely the influence of skull, muscle and brain anisotropic conductivities in a volume conductor model. MAIN RESULTS Anisotropy modulated current-flow in a montage and region dependent manner. However, significant statistical changes, produced within montage by anisotropy, did not change qualitative peak and topographic comparisons across montages. Thus for the examples analysed, clinical decision on which dose to select would not be altered by the omission of anisotropic brain conductivity. SIGNIFICANCE Results illustrate the need to rationally balance the role of model complexity, such as anisotropy in detailed current flow analysis versus value in clinical dose design. However, when extending our analysis to include axonal polarization, the results provide presumably clinically meaningful information. Hence the importance of model complexity may be more relevant with cellular level predictions of neuromodulation.
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Affiliation(s)
- Syed Salman Shahid
- Research Center for Modeling and Simulation, National University of Sciences and Technology, Islamabad, Pakistan. School of Mechanical and Electrical Engineering, University of Southern Queensland, Toowoomba, QLD, Australia
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Morgan HM, Davis NJ, Bracewell RM. Does transcranial direct current stimulation to prefrontal cortex affect mood and emotional memory retrieval in healthy individuals? PLoS One 2014; 9:e92162. [PMID: 24651375 PMCID: PMC3961298 DOI: 10.1371/journal.pone.0092162] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 02/19/2014] [Indexed: 11/18/2022] Open
Abstract
Studies using transcranial direct current stimulation (tDCS) of prefrontal cortex to improve symptoms of depression have had mixed results. We examined whether using tDCS to change the balance of activity between left and right dorsolateral prefrontal cortex (DLPFC) can alter mood and memory retrieval of emotional material in healthy volunteers. Participants memorised emotional images, then tDCS was applied bilaterally to DLPFC while they performed a stimulus-response compatibility task. Participants were then presented with a set of images for memory retrieval. Questionnaires to examine mood and motivational state were administered at the beginning and end of each session. Exploratory data analyses showed that the polarity of tDCS to DLPFC influenced performance on a stimulus-response compatibility task and this effect was dependent on participants' prior motivational state. However, tDCS polarity had no effect on the speed or accuracy of memory retrieval of emotional images and did not influence positive or negative affect. These findings suggest that the balance of activity between left and right DLPFC does not play a critical role in the mood state of healthy individuals. We suggest that the efficacy of prefrontal tDCS depends on the initial activation state of neurons and future work should take this into account.
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Affiliation(s)
- Helen M. Morgan
- School of Natural Sciences & Psychology, Liverpool John Moores University, Liverpool, United Kingdom
- * E-mail:
| | - Nick J. Davis
- Department of Psychology, Swansea University, Swansea, United Kingdom
| | - R. Martyn Bracewell
- School of Psychology and School of Medical Sciences, Bangor University, Bangor, United Kingdom
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Abstract
Doping may be defined, broadly, as the use of unauthorised means to increase performance in sport. Doping is most commonly associated with the use of drugs. In this paper, I discuss the use of emerging techniques for the modulation of brain activity in healthy people using electric or magnetic fields, and suggest how they might be used to enhance physical and mental performance in sports. I will suggest that neurodoping may have different uses in different sports, and I argue that each sport must determine whether neurodoping should be considered as cheating, or should be considered a legitimate aid to training or performance.
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Affiliation(s)
- Nick J Davis
- School of Psychology, Bangor University, Bangor, LL57 2AS, UK.
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Repeated transcranial direct current stimulation prevents abnormal behaviors associated with abstinence from chronic nicotine consumption. Neuropsychopharmacology 2014; 39:981-8. [PMID: 24154668 PMCID: PMC3924532 DOI: 10.1038/npp.2013.298] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Revised: 10/02/2013] [Accepted: 10/16/2013] [Indexed: 11/08/2022]
Abstract
Successful available treatments to quit smoking remain scarce. Recently, the potential of transcranial direct current stimulation (tDCS) as a tool to reduce craving for nicotine has gained interest. However, there is no documented animal model to assess the neurobiological mechanisms of tDCS on addiction-related behaviors. To address this topic, we have developed a model of repeated tDCS in mice and used it to validate its effectiveness in relieving nicotine addiction. Anodal repeated tDCS was applied over the frontal cortex of Swiss female mice. The stimulation electrode (anode) was fixed directly onto the cranium, and the reference electrode was placed onto the ventral thorax. A 2 × 20 min/day stimulation paradigm for five consecutive days was used (0.2 mA). In the first study, we screened for behaviors altered by the stimulation. Second, we tested whether tDCS could alleviate abnormal behaviors associated with abstinence from nicotine consumption. In naive animals, repeated tDCS had antidepressant-like properties 3 weeks after the last stimulation, improved working memory, and decreased conditioned place preference for nicotine without affecting locomotor activity and anxiety-related behavior. Importantly, abnormal behaviors associated with chronic nicotine exposure (ie, depression-like behavior, increase in nicotine-induced place preference) were normalized by repeated tDCS. Our data show for the first time in an animal model that repeated tDCS is a promising, non-expensive clinical tool that could be used to reduce smoking craving and facilitate smoking cessation. Our animal model will be useful to investigate the mechanisms underlying the effects of tDCS on addiction and other psychiatric disorders.
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225
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Jotterand F. Questioning the moral enhancement project. THE AMERICAN JOURNAL OF BIOETHICS : AJOB 2014; 14:1-3. [PMID: 24730478 DOI: 10.1080/15265161.2014.905031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
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226
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Agarwal SM, Shivakumar V, Bose A, Subramaniam A, Nawani H, Chhabra H, Kalmady SV, Narayanaswamy JC, Venkatasubramanian G. Transcranial direct current stimulation in schizophrenia. CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE 2013; 11:118-25. [PMID: 24465247 PMCID: PMC3897759 DOI: 10.9758/cpn.2013.11.3.118] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 12/03/2013] [Accepted: 12/04/2013] [Indexed: 01/01/2023]
Abstract
Transcranial direct current stimulation (tDCS) is an upcoming treatment modality for patients with schizophrenia. A series of recent observations have demonstrated improvement in clinical status of schizophrenia patients with tDCS. This review summarizes the research work that has examined the effects of tDCS in schizophrenia patients with respect to symptom amelioration, cognitive enhancement and neuroplasticity evaluation. tDCS is emerging as a safe, rapid and effective treatment for various aspects of schizophrenia symptoms ranging from auditory hallucinations-for which the effect is most marked, to negative symptoms and cognitive symptoms as well. An interesting line of investigation involves using tDCS for altering and examining neuroplasticity in patients and healthy subjects and is likely to lead to new insights into the neurological aberrations and pathophysiology of schizophrenia. The mechanistic aspects of the technique are discussed in brief. Future work should focus on establishing the clinical efficacy of this novel technique and on evaluating this modality as an adjunct to cognitive enhancement protocols. Understanding the mechanism of action of tDCS as well as the determinants and neurobiological correlates of clinical response to tDCS remains an important goal, which will help us expand the clinical applications of tDCS for the treatment of patients with schizophrenia.
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Affiliation(s)
- Sri Mahavir Agarwal
- The Schizophrenia Clinic, Department of Psychiatry and Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Venkataram Shivakumar
- The Schizophrenia Clinic, Department of Psychiatry and Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Anushree Bose
- The Schizophrenia Clinic, Department of Psychiatry and Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Aditi Subramaniam
- The Schizophrenia Clinic, Department of Psychiatry and Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Hema Nawani
- The Schizophrenia Clinic, Department of Psychiatry and Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Harleen Chhabra
- The Schizophrenia Clinic, Department of Psychiatry and Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Sunil V Kalmady
- The Schizophrenia Clinic, Department of Psychiatry and Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Janardhanan C Narayanaswamy
- The Schizophrenia Clinic, Department of Psychiatry and Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Ganesan Venkatasubramanian
- The Schizophrenia Clinic, Department of Psychiatry and Translational Psychiatry Laboratory, Neurobiology Research Centre, National Institute of Mental Health and Neurosciences, Bangalore, India
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227
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Davis NJ, van Koningsbruggen MG. "Non-invasive" brain stimulation is not non-invasive. Front Syst Neurosci 2013; 7:76. [PMID: 24391554 PMCID: PMC3870277 DOI: 10.3389/fnsys.2013.00076] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 12/06/2013] [Indexed: 11/13/2022] Open
Affiliation(s)
- Nick J Davis
- Department of Psychology, Swansea University Swansea, UK
| | - Martijn G van Koningsbruggen
- Centro Interdipartimentale Mente/Cervello, University of Trento Rovereto, Italy ; Department of Cognitive Sciences, University of Trento Rovereto, Italy
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228
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Sohn MK, Jee SJ, Kim YW. Effect of transcranial direct current stimulation on postural stability and lower extremity strength in hemiplegic stroke patients. Ann Rehabil Med 2013; 37:759-65. [PMID: 24466510 PMCID: PMC3895515 DOI: 10.5535/arm.2013.37.6.759] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 08/13/2013] [Indexed: 11/23/2022] Open
Abstract
Objective To evaluate the effect of anodal transcranial direct current stimulation (tDCS) over the lesioned leg motor cortex, which can enhance the strength and coordination of the contralateral lower extremity and furthermore, enhance the postural stability of the hemiplegic subject. Methods Anodal or sham stimulation on the lesioned cortex of a lower extremity was delivered to 11 ambulatory hemiplegic patients. The stimulation intensity was 2 mA. All subjects took part in two 10-minute tDCS sessions consisting of anodal stimulation and sham stimulation. The interval period between real and sham stimulation was 48 hours. The order was counter-balanced among the subjects. Before and after each stimulation session, static postural stability was evaluated with eyes opened and closed. Also, the isometric strength of the hemiplegic side of the treated knee was measured before and after each stimulation session. Repeated measure ANOVA was used to determine the statistical significance of improvements in postural stability and strength. Results There was significant improvement for overall stability index with eyes opened and closed after anodal tDCS (p<0.05). Isometric strength of the lesioned quadriceps tended to increase after anodal tDCS (p<0.05). Postural stability and quadriceps strength were not changed after sham stimulation. Conclusion Anodal tDCS has potential value in hemiplegic stroke patients to improve balance and strengthen the affected lower extremity.
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Affiliation(s)
- Min Kyun Sohn
- Department of Rehabilitation Medicine, Chungnam National University School of Medicine, Daejeon, Korea
| | - Sung Ju Jee
- Department of Rehabilitation Medicine, Chungnam National University School of Medicine, Daejeon, Korea
| | - Yeong Wook Kim
- Department of Rehabilitation Medicine, Chungnam National University School of Medicine, Daejeon, Korea
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Micoulaud-Franchi JA, Richieri R, Lancon C, Vion-Dury J. Protocoles de rTMS interactives en psychiatrie. Encephale 2013; 39:426-31. [DOI: 10.1016/j.encep.2013.04.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Accepted: 02/07/2013] [Indexed: 11/28/2022]
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230
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Fagerlund AJ, Bystad MK, Aslaksen PM. [Transcranial direct current stimulation for chronic pain]. TIDSSKRIFT FOR DEN NORSKE LEGEFORENING 2013; 133:2266-9. [PMID: 24226334 DOI: 10.4045/tidsskr.13.0003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
BACKGROUND Transcranial Direct Current Stimulation (tDCS) is a non-invasive method for neuromodulation. By changing the neurons' resting membrane potential, the method can alter the activity in areas of the brain. We therefore wished to review randomised controlled trials (RCTs) that investigate the treatment effect of tDCS on chronic pain. EVIDENCE We undertook a search in PubMed with the search terms «transcranial direct current stimulation» and «pain», with «randomized controlled trial» as a filter. RESULTS Five randomised, controlled trials that used quantitative outcome measures for pain were identified. The studies focused on strongly varying groups of patients suffering from pain. The results from some of the studies showed that stimulation with the aid of tDCS led to a significantly lower level of pain, but seen as a whole, the results were not conclusive. INTERPRETATION The method should be further investigated in studies that include clearly defined groups of patients suffering from pain, as well as a larger number of participants, before implementation of the method is considered as a treatment option for chronic pain.
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231
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Fiquer JT, Boggio PS, Gorenstein C. Talking bodies: nonverbal behavior in the assessment of depression severity. J Affect Disord 2013; 150:1114-9. [PMID: 23706840 DOI: 10.1016/j.jad.2013.05.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 05/03/2013] [Indexed: 10/26/2022]
Abstract
BACKGROUND Evaluations of clinical depression are traditionally based on verbal information. Nonverbal expressive behavior, however, being associated with a person's reflexive responses, may reveal negative emotional or social processes that are not under complete control of the patients. However, investigations of nonverbal behavior in the evaluation of depressed patients are still scarce. This study examines the nonverbal behaviors of a group of Brazilian patients, associating their nonverbal behavior with severity of depression. METHODS Forty depressed patients were evaluated at baseline (T0) and after a two-week transcranial direct current stimulation treatment (T1), according to rating scales and through a 21-category Ethogram for assessment of the frequency of nonverbal behaviors displayed during an interview. RESULTS Behaviors that were related to negative feelings and social disinterest decreased with corresponding clinical improvement and were associated with increased severity of symptoms at T0 and greater negative affect and dissatisfaction at T1. Pro-social behaviors were associated with milder symptoms at T0 and increased after treatment. Facial, head and hand expressive movements stood out as important indicators because of their associations with severity of depression. LIMITATIONS Duration of behaviors was not assessed and there was not a healthy control group with which to compare the findings. CONCLUSIONS These results support the usefulness of nonverbal behavior as an evaluation technique in the assessment of clinical depression.
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232
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McClelland J, Bozhilova N, Campbell I, Schmidt U. A systematic review of the effects of neuromodulation on eating and body weight: evidence from human and animal studies. EUROPEAN EATING DISORDERS REVIEW 2013; 21:436-55. [PMID: 24155246 DOI: 10.1002/erv.2256] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Revised: 08/17/2013] [Indexed: 01/17/2023]
Abstract
BACKGROUND Eating disorders (ED) are chronic and sometimes deadly illnesses. Existing treatments have limited proven efficacy, especially in the case of adults with anorexia nervosa (AN). Emerging neural models of ED provide a rationale for more targeted, brain-directed interventions. AIMS This systematic review has examined the effects of neuromodulation techniques on eating behaviours and body weight and assessed their potential for therapeutic use in ED. METHOD All articles in PubMed, PsychInfo and Web of Knowledge were considered and screened against a priori inclusion/exclusion criteria. The effects of repetitive transcranial magnetic stimulation (rTMS), transcranial direct current stimulation, vagus nerve stimulation (VNS) and deep brain stimulation (DBS) were examined across studies in ED samples, other psychiatric and neurological disorders, and animal models. RESULTS Sixty studies were identified. There is evidence for ED symptom reduction following rTMS and DBS in both AN and bulimia nervosa. Findings from studies of other psychiatric and neurological disorders and from animal studies demonstrate that increases in food intake and body weight can be achieved following DBS and that VNS has potential value as a means of controlling eating and inducing weight loss. CONCLUSIONS Neuromodulation tools have potential for reducing ED symptomatology and related behaviours, and for altering food intake and body weight. In response to such findings, and emerging neural models of ED, treatment approaches are highly unlikely to remain 'brainless'. More research is required to evaluate the potential of neuromodulation procedures for improving long-term outcomes in ED.
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Affiliation(s)
- Jessica McClelland
- Section of Eating Disorders, Institute of Psychiatry, King's College London, London, UK
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233
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Motohashi N, Yamaguchi M, Fujii T, Kitahara Y. Mood and cognitive function following repeated transcranial direct current stimulation in healthy volunteers: A preliminary report. Neurosci Res 2013; 77:64-9. [DOI: 10.1016/j.neures.2013.06.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Revised: 06/04/2013] [Accepted: 06/17/2013] [Indexed: 11/27/2022]
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234
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Mekonnen A, Salvador R, Ruffini G, Miranda PC. The relationship between transcranial current stimulation electrode montages and the effect of the skull orbital openings. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2013; 2012:831-4. [PMID: 23366021 DOI: 10.1109/embc.2012.6346060] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Due to its low electric conductivity, the skull has a major impact on the electric field distribution in the brain in transcranial current stimulation (tCS). However, the skull has several openings that are filled with higher conductivity soft tissues, and through which a significant fraction of the injected current may pass. We show that current entering the brain via the orbital openings increases the electric field intensity in the cortical regions near the orbit. Furthermore, this depends on the how far electrodes are placed from the orbital openings.
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Affiliation(s)
- A Mekonnen
- Institute of Biophysics and Biomedical Engineering (IBEB), Faculty of Sciences, University of Lisbon, Lisbon, Portugal.
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235
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Volpato C, Piccione F, Cavinato M, Duzzi D, Schiff S, Foscolo L, Venneri A. Modulation of affective symptoms and resting state activity by brain stimulation in a treatment-resistant case of obsessive-compulsive disorder. Neurocase 2013; 19:360-70. [PMID: 22554168 DOI: 10.1080/13554794.2012.667131] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The effect of transcranial direct current stimulation (tDCS) and repetitive transcranial magnetic stimulation (rTMS) on psychopathological symptoms and resting state brain activity was assessed in a patient with obsessive-compulsive disorder (OCD). tDCS and rTMS had no effect on OC symptoms. tDCS, however, improved depression and anxiety. Functional magnetic resonance imaging at baseline showed an interhemispheric asymmetry with hyperactivation of the left and hypoactivation of the right anterior neural circuits. A reduction of interhemispheric imbalance was detected after tDCS but not after rTMS. tDCS seems to be more effective than rTMS in restoring interhemispheric imbalance and improving anxiety and depression in OCD.
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236
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Jung YJ, Kim JH, Kim D, Im CH. An image-guided transcranial direct current stimulation system: a pilot phantom study. Physiol Meas 2013; 34:937-50. [DOI: 10.1088/0967-3334/34/8/937] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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237
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Lipsman N, Sankar T, Downar J, Kennedy SH, Lozano AM, Giacobbe P. Neuromodulation for treatment-refractory major depressive disorder. CMAJ 2013; 186:33-9. [PMID: 23897945 DOI: 10.1503/cmaj.121317] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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Metwally MK, Cho YS, Park HJ, Kim TS. Investigation of the electric field components of tDCS via anisotropically conductive gyri-specific finite element head models. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2013; 2012:5514-7. [PMID: 23367178 DOI: 10.1109/embc.2012.6347243] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Transcranial Direct Current Stimulation (tDCS) is considered as one of the promising techniques for noninvasive brain stimulation and brain disease therapy. In this study, we have investigated the effect of skull and white matter (WM) anisotropy on the induced electric field (EF) by tDCS in two different montages; one using a pair of clinically used rectangular pad electrodes and the other 4(cathodes)+1(anode) ring electrodes. Using a gyri-specific finite element (FE) head model, we simulated tDCS and investigated the radial and tangential components of the induced EF in terms of their distribution over the cortical surface besides the distribution of the transverse and longitudinal components within WM. The results show that the tangential component of the EF on the cortical surface seems to be the main cause of the cortical stimulation of tDCS. Also WM anisotropy seems to increase the dispersion of the transverse component of the EF that affects the dispersion of the EF magnitude within the WM region.
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Affiliation(s)
- Mohamed K Metwally
- Department of Biomedical Engineering, Kyung Hee University, Yongin, Gyeonggi, Republic of Korea
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239
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Hauser TU, Rotzer S, Grabner RH, Mérillat S, Jäncke L. Enhancing performance in numerical magnitude processing and mental arithmetic using transcranial Direct Current Stimulation (tDCS). Front Hum Neurosci 2013; 7:244. [PMID: 23761750 PMCID: PMC3674316 DOI: 10.3389/fnhum.2013.00244] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Accepted: 05/17/2013] [Indexed: 12/30/2022] Open
Abstract
The ability to accurately process numerical magnitudes and solve mental arithmetic is of highest importance for schooling and professional career. Although impairments in these domains in disorders such as developmental dyscalculia (DD) are highly detrimental, remediation is still sparse. In recent years, transcranial brain stimulation methods such as transcranial Direct Current Stimulation (tDCS) have been suggested as a treatment for various neurologic and neuropsychiatric disorders. The posterior parietal cortex (PPC) is known to be crucially involved in numerical magnitude processing and mental arithmetic. In this study, we evaluated whether tDCS has a beneficial effect on numerical magnitude processing and mental arithmetic. Due to the unclear lateralization, we stimulated the left, right as well as both hemispheres simultaneously in two experiments. We found that left anodal tDCS significantly enhanced performance in a number comparison and a subtraction task, while bilateral and right anodal tDCS did not induce any improvements compared to sham. Our findings demonstrate that the left PPC is causally involved in numerical magnitude processing and mental arithmetic. Furthermore, we show that these cognitive functions can be enhanced by means of tDCS. These findings encourage to further investigate the beneficial effect of tDCS in the domain of mathematics in healthy and impaired humans.
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Affiliation(s)
- Tobias U Hauser
- Division Neuropsychology, Institute of Psychology, University of Zurich Zurich, Switzerland ; University Clinics for Child and Adolescent Psychiatry, University of Zurich Zurich, Switzerland ; Neuroscience Center Zurich, University of Zurich and ETH Zurich Zurich, Switzerland
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240
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Kuo MF, Paulus W, Nitsche MA. Therapeutic effects of non-invasive brain stimulation with direct currents (tDCS) in neuropsychiatric diseases. Neuroimage 2013; 85 Pt 3:948-60. [PMID: 23747962 DOI: 10.1016/j.neuroimage.2013.05.117] [Citation(s) in RCA: 278] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Revised: 04/30/2013] [Accepted: 05/23/2013] [Indexed: 12/19/2022] Open
Abstract
Neuroplasticity, which is the dynamic structural and functional reorganization of central nervous system connectivity due to environmental and internal demands, is recognized as a major physiological basis for adaption of cognition, and behavior, and thus of utmost importance for normal brain function. Pathological alterations of plasticity are increasingly explored as pathophysiological foundation of diverse neurological and psychiatric diseases. Non-invasive brain stimulation techniques (NIBS), such as repetitive transcranial magnetic stimulation (rTMS), and transcranial direct current stimulation (tDCS), are able to induce and modulate neuroplasticity in humans. Therefore, they have potential to alter pathological plasticity on the one hand, and foster physiological plasticity on the other, in neuropsychiatric diseases to reduce symptoms, and enhance rehabilitation. tDCS is an emerging NIBS tool, which induces glutamatergic plasticity via application of relatively weak currents through the scalp in humans. In the last years its efficacy to treat neuropsychiatric diseases has been explored increasingly. In this review, we will give an overview of pathological alterations of plasticity in neuropsychiatric diseases, gather clinical studies involving tDCS to ameliorate symptoms, and discuss future directions of application, with an emphasis on optimizing stimulation effects.
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Affiliation(s)
- Min-Fang Kuo
- University Medical Center, Clinic for Clinical Neurophysiology, Georg-August-University, Robert-Koch-Str. 40, 37099 Goettingen, Germany.
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241
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Modulation of spinal neuronal excitability by spinal direct currents and locomotion after spinal cord injury. Clin Neurophysiol 2013; 124:1187-95. [DOI: 10.1016/j.clinph.2012.11.021] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Revised: 10/29/2012] [Accepted: 11/05/2012] [Indexed: 12/18/2022]
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242
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Jung YJ, Kim JH, Im CH. COMETS: A MATLAB toolbox for simulating local electric fields generated by transcranial direct current stimulation (tDCS). Biomed Eng Lett 2013. [DOI: 10.1007/s13534-013-0087-x] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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243
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Tanaka T, Takano Y, Tanaka S, Hironaka N, Kobayashi K, Hanakawa T, Watanabe K, Honda M. Transcranial direct-current stimulation increases extracellular dopamine levels in the rat striatum. Front Syst Neurosci 2013; 7:6. [PMID: 23596399 PMCID: PMC3622879 DOI: 10.3389/fnsys.2013.00006] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Accepted: 03/16/2013] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Transcranial direct-current stimulation (tDCS) is a non-invasive procedure that achieves polarity-dependent modulation of neuronal membrane potentials. It has recently been used as a functional intervention technique for the treatment of psychiatric and neurological diseases; however, its neuronal mechanisms have not been fully investigated in vivo. OBJECTIVE/HYPOTHESIS To investigate whether the application of cathodal or anodal tDCS affects extracellular dopamine and serotonin levels in the rat striatum. METHODS Stimulation and in vivo microdialysis were carried out under urethane anesthesia, and microdialysis probes were slowly inserted into the striatum. After the collection of baseline fractions in the rat striatum, cathodal or anodal tDCS was applied continuously for 10 min with a current intensity of 800 μA from an electrode placed on the skin of the scalp. Dialysis samples were collected every 10 min until at least 400 min after the onset of stimulation. RESULTS Following the application of cathodal, but not anodal, tDCS for 10 min, extracellular dopamine levels increased for more than 400 min in the striatum. There were no significant changes in extracellular serotonin levels. CONCLUSION These findings suggest that tDCS has a direct and/or indirect effect on the dopaminergic system in the rat basal ganglia.
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Affiliation(s)
- Tomoko Tanaka
- Department of Functional Brain Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry Tokyo, Japan
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244
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David CN, Rapoport JL, Gogtay N. Treatments in context: transcranial direct current brain stimulation as a potential treatment in pediatric psychosis. Expert Rev Neurother 2013; 13:447-58. [PMID: 23545058 PMCID: PMC4063712 DOI: 10.1586/ern.13.29] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Childhood-onset schizophrenia is a chronic, severe form of schizophrenia, and is typically treatment resistant. Even after optimized pharmacotherapy, a majority (over 70%) of these pediatric patients present lasting psychotic symptoms and impaired cognition, necessitating the need for novel treatment modalities. Recent work in transcranial magnetic stimulation suggests moderate efficacy in symptom reduction in adult patients with schizophrenia; however, the transcranial magnetic stimulation treatment is cumbersome for this severely ill population. Transcranial direct current stimulation may provide a safe and effective adjuvant treatment for continued residual symptoms of schizophrenia.
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Affiliation(s)
- Christopher N David
- Child Psychiatry Branch, National Institute of Mental Health (NIMH), National Institutes of Health (NIH), Building 10, Room 3N202, 10 Center Drive, Bethesda, MD 20890, USA
| | - Judith L Rapoport
- Child Psychiatry Branch, National Institute of Mental Health (NIMH), National Institutes of Health (NIH), Building 10, Room 3N202, 10 Center Drive, Bethesda, MD 20890, USA
| | - Nitin Gogtay
- Child Psychiatry Branch, National Institute of Mental Health (NIMH), National Institutes of Health (NIH), Building 10, Room 3N202, 10 Center Drive, Bethesda, MD 20890, USA
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245
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Pinchuk D, Pinchuk O, Sirbiladze K, Shugar O. Clinical effectiveness of primary and secondary headache treatment by transcranial direct current stimulation. Front Neurol 2013; 4:25. [PMID: 23519166 PMCID: PMC3604631 DOI: 10.3389/fneur.2013.00025] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Accepted: 03/01/2013] [Indexed: 11/13/2022] Open
Abstract
The clinical effectiveness of primary and secondary headache treatment by transcranial direct current stimulation (tDCS) with various locations of stimulating electrodes on the scalp was analyzed retrospectively. The results of the treatment were analyzed in 90 patients aged from 19 to 54 years (48 patients had migraine without aura, 32 - frequent episodic tension-type HAs, 10 - chronic tension-type HAs) and in 44 adolescents aged 11-16 years with chronic post-traumatic HAs after a mild head injury. Clinical effectiveness of tDCS with 70-150 μA current for 30-45 min via 6.25 cm(2) stimulating electrodes is comparable to that of modern pharmacological drugs, with no negative side effects. The obtained result has been maintained on average from 5 to 9 months. It has been demonstrated that effectiveness depends on localization of stimulating electrodes used for different types of HAs.
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Affiliation(s)
- Dmitry Pinchuk
- Department of Neurology, Municipal Center for Medical Rehabilitation of Children with Psychoneurological Disorders Saint Petersburg, Russia ; Neurolife SA Lausanne, Switzerland
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246
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Dmochowski JP, Datta A, Huang Y, Richardson JD, Bikson M, Fridriksson J, Parra LC. Targeted transcranial direct current stimulation for rehabilitation after stroke. Neuroimage 2013; 75:12-19. [PMID: 23473936 DOI: 10.1016/j.neuroimage.2013.02.049] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2012] [Revised: 02/13/2013] [Accepted: 02/19/2013] [Indexed: 11/28/2022] Open
Abstract
Transcranial direct current stimulation (tDCS) is being investigated as an adjunctive technique to behavioral rehabilitation treatment after stroke. The conventional "dosage", consisting of a large (25 cm(2)) anode over the target with the cathode over the contralateral hemisphere, has been previously shown to yield broadly distributed electric fields whose intensities at the target region are less than maximal. Here, we report the results of a systematic targeting procedure with small "high-definition" electrodes that was used in preparation for a pilot study on 8 stroke patients with chronic aphasia. We employ functional and anatomical magnetic resonance imagery (fMRI/MRI) to define a target and optimize (with respect to the electric field magnitude at the target) the electrode configuration, respectively, and demonstrate that electric field strengths in targeted cortex can be substantially increased (63%) over the conventional approach. The optimal montage exhibits significant variation across subjects as well as when perturbing the target location within a subject. However, for each displacement of the target co-ordinates, the algorithm is able to determine a montage which delivers a consistent amount of current to that location. These results demonstrate that MRI-based models of current flow yield maximal stimulation of target structures, and as such, may aid in reliably assessing the efficacy of tDCS in neuro-rehabilitation.
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Affiliation(s)
| | | | - Yu Huang
- City College of New York, New York, NY, USA
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247
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Effects of transcranial direct current stimulation during sleep on memory performance in patients with schizophrenia. Schizophr Res 2013; 144:153-4. [PMID: 23336963 DOI: 10.1016/j.schres.2012.12.014] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Revised: 12/20/2012] [Accepted: 12/26/2012] [Indexed: 11/24/2022]
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248
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Hahn C, Rice J, Macuff S, Minhas P, Rahman A, Bikson M. Methods for extra-low voltage transcranial direct current stimulation: Current and time dependent impedance decreases. Clin Neurophysiol 2013; 124:551-6. [DOI: 10.1016/j.clinph.2012.07.028] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Revised: 07/06/2012] [Accepted: 07/10/2012] [Indexed: 10/27/2022]
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249
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Martin DM, Alonzo A, Ho KA, Player M, Mitchell PB, Sachdev P, Loo CK. Continuation transcranial direct current stimulation for the prevention of relapse in major depression. J Affect Disord 2013; 144:274-8. [PMID: 23146197 DOI: 10.1016/j.jad.2012.10.012] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Revised: 10/18/2012] [Accepted: 10/18/2012] [Indexed: 11/19/2022]
Abstract
BACKGROUND Transcranial direct current stimulation (tDCS) is gaining attention as an effective new treatment for major depression. Little is known, however, of the duration of antidepressant effects following acute treatment. In this study, we describe the use of continuation tDCS treatment for up to 6 months following clinical response to an acute treatment course. METHODS Twenty-six participants pooled from two different studies involving different tDCS protocols received continuation tDCS treatment on a weekly basis for 3 months and then once per fortnight for the final 3 months. Mood ratings were completed at 3 and 6 months. Analyses examined clinical predictors of relapse during continuation tDCS treatment. RESULTS The cumulative probability of surviving without relapse was 83.7% at 3 months and 51.1% at 6 months. Medication resistance was found to be a predictor of relapse during continuation tDCS. LIMITATIONS This was an open label prospective study with no control group. Two different forms of tDCS were used. CONCLUSION Similar to other antidepressant treatments, continuation tDCS appears to be a useful strategy to prevent relapse following clinical response. These preliminary data suggest that the majority of patients maintained antidepressant benefit with a continuation schedule of at least weekly treatment. Future controlled studies are required to confirm these findings.
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Affiliation(s)
- Donel M Martin
- Black Dog Institute, School of Psychiatry, University of New South Wales, Sydney, Australia
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250
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Wu D, Qian L, Zorowitz RD, Zhang L, Qu Y, Yuan Y. Effects on Decreasing Upper-Limb Poststroke Muscle Tone Using Transcranial Direct Current Stimulation: A Randomized Sham-Controlled Study. Arch Phys Med Rehabil 2013; 94:1-8. [DOI: 10.1016/j.apmr.2012.07.022] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2012] [Revised: 07/24/2012] [Accepted: 07/30/2012] [Indexed: 12/17/2022]
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