Imaging transcranial direct current stimulation (tDCS) of the prefrontal cortex—correlation or causality in stimulation-mediated effects?

Achard, 2006, A resilient, low-frequency, small-world human brain functional network with highly connected association cortical hubs, J. Neurosci., 26, 63, 10.1523/JNEUROSCI.3874-05.2006

Achermann, 2003, Mathematical models of sleep regulation, Front. Biosci., 8, s683, 10.2741/1064

Antal, 2015, Brain Stimul., 8, 846, 10.1016/j.brs.2015.05.010

Ardolino, 2005, Non-synaptic mechanisms underlie the after-effects of cathodal transcutaneous direct current stimulation of the human brain, J. Physiol., 568, 653, 10.1113/jphysiol.2005.088310

Arul-Anandam, 2009, Chronic neuropathic pain alleviation after transcranial direct current stimulation to the dorsolateral prefrontal cortex, Brain Stimul., 2, 149, 10.1016/j.brs.2008.12.003

Bai, 2014, A computational modelling study of transcranial direct current stimulation montages used in depression, Neuroimage, 87, 332, 10.1016/j.neuroimage.2013.11.015

Balconi, 2012, The tDCS effect on alpha brain oscillation for correct vs. incorrect object use. The contribution of the left DLPFC, Neurosci. Lett., 517, 25, 10.1016/j.neulet.2012.04.010

Balconi, 2014, Dorsolateral pFC and the representation of the incorrect use of an object: the transcranial direct current stimulation effect on N400 for visual and linguistic stimuli, J. Cogn. Neurosci., 26, 305, 10.1162/jocn_a_00500

Barr, 2012, A randomized controlled trial of sequentially bilateral prefrontal cortex repetitive transcranial magnetic stimulation in the treatment of negative symptoms in schizophrenia, Brain Stimul., 5, 337, 10.1016/j.brs.2011.06.003

Bassett, 2006, Small-world brain networks, Neuroscientist, 12, 512, 10.1177/1073858406293182

Baudewig, 2001, Regional modulation of BOLD MRI responses to human sensorimotor activation by transcranial direct current stimulation, Magn. Reson. Med., 45, 196, 10.1002/1522-2594(200102)45:2<196::AID-MRM1026>3.0.CO;2-1

Been, 2007, The use of tDCS and CVS as methods of non-invasive brain stimulation, Brain Res. Rev., 56, 346, 10.1016/j.brainresrev.2007.08.001

Bellaïche, 2013, The modulation of error processing in the medial frontal cortex by transcranial direct current stimulation, Neurosci. J., 2013, 1, 10.1155/2013/187692

Bestmann, 2015, Understanding the behavioural consequences of noninvasive brain stimulation, Trends Cogn. Sci., 19, 13, 10.1016/j.tics.2014.10.003

Bikson, 2010, Electrode montages for tDCS and weak transcranial electrical stimulation: role of return electrode's position and size, Clin. Neurophysiol., 121, 1976, 10.1016/j.clinph.2010.05.020

Bikson, 2016, Safety of transcranial direct current stimulation: evidence based update 2016, Brain Stimul., 10.1016/j.brs.2016.06.004

Bindman, 1962, Long-lasting changes in the level of the electrical activity of the cerebral cortex produced by polarizing currents, Nature, 196, 584, 10.1038/196584a0

Bindman, 1963, Comparison of the effects on electrocortical activity of general body cooling of the surface of the brain, Electroencephalogr. Clin. Neurophysiol., 15, 238, 10.1016/0013-4694(63)90093-2

Binkofski, 2011, Brain energy consumption induced by electrical stimulation promotes systemic glucose uptake, Biol. Psychiatry, 70, 690, 10.1016/j.biopsych.2011.05.009

Biswal, 2010, Toward discovery science of human brain function, Proc. Natl. Acad. Sci. U. S. A., 107, 4734, 10.1073/pnas.0911855107

Boggio, 2006, Effects of transcranial direct current stimulation on working memory in patients with Parkinson's disease, J. Neurol. Sci., 249, 31, 10.1016/j.jns.2006.05.062

Boggio, 2008, A randomized, double-blind clinical trial on the efficacy of cortical direct current stimulation for the treatment of major depression, Int. J. Neuropsychopharmacol., 11, 249, 10.1017/S1461145707007833

Boggio, 2009, Cumulative priming effects of cortical stimulation on smoking cue-induced craving, Neurosci. Lett., 463, 82, 10.1016/j.neulet.2009.07.041

Boly, 2008, Intrinsic brain activity in altered states of consciousness: how conscious is the default mode of brain function?, Ann. N. Y. Acad. Sci., 1129, 119, 10.1196/annals.1417.015

Boros, 2008, Premotor transcranial direct current stimulation (tDCS) affects primary motor excitability in humans, Eur. J. Neurosci., 27, 1292, 10.1111/j.1460-9568.2008.06090.x

Bose, 2014, Insight facilitation with add-on tDCS in schizophrenia, Schizophr. Res., 156, 63, 10.1016/j.schres.2014.03.029

Brunelin, 2012, Examining transcranial direct-current stimulation (tDCS) as a treatment for hallucinations in schizophrenia, Am. J. Psychiatry, 169, 719, 10.1176/appi.ajp.2012.11071091

Brunoni, 2012, Clinical research with transcranial direct current stimulation (tDCS): challenges and future directions, Brain Stimul., 5, 175, 10.1016/j.brs.2011.03.002

Brunoni, 2013, The sertraline vs. electrical current therapy for treating depression clinical study: results from a factorial, randomized, controlled trial, JAMA Psychiatry, 70, 383, 10.1001/2013.jamapsychiatry.32

Buckner, 2008, The brain's default network: anatomy, function, and relevance to disease, Ann. N. Y. Acad. Sci., 1124, 1, 10.1196/annals.1440.011

Chew, 2015, Inter- and intra-individual variability in response to transcranial direct current stimulation (tDCS) at varying current intensities, Brain Stimul., 8, 1130, 10.1016/j.brs.2015.07.031

Chib, 2013, Noninvasive remote activation of the ventral midbrain by transcranial direct current stimulation of prefrontal cortex, Transl. Psychiatry, 3, e268, 10.1038/tp.2013.44

Clark, 2011, Transcranial direct current stimulation (tDCS) produces localized and specific alterations in neurochemistry: a (1)H magnetic resonance spectroscopy study, Neurosci. Lett., 500, 67, 10.1016/j.neulet.2011.05.244

Conti, 2014, Bilateral transcranial direct current stimulation over dorsolateral prefrontal cortex changes the drug-cued reactivity in the anterior cingulate cortex of crack-cocaine addicts, Brain Stimul., 7, 130, 10.1016/j.brs.2013.09.007

Corbetta, 2002, Control of goal-directed and stimulus-driven attention in the brain, Nat. Rev. Neurosci., 3, 201, 10.1038/nrn755

Creutzfeldt, 1962, Influence of transcortical d-c currents on cortical neuronal activity, Exp. Neurol., 5, 436, 10.1016/0014-4886(62)90056-0

Cunillera, 2015, The right inferior frontal cortex in response inhibition: a tDCS-ERP Co-registration study, Neuroimage

DaSilva, 2015, State-of-art neuroanatomical target analysis of high-definition and conventional tDCS montages used for migraine and pain control, Front. Neuroanat., 9, 89, 10.3389/fnana.2015.00089

da Silva, 2013, Behavioral effects of transcranial direct current stimulation (tDCS) induced dorsolateral prefrontal cortex plasticity in alcohol dependence, J. Physiol. Paris, 10.1016/j.jphysparis.2013.07.003

Datta, 2008, Transcranial current stimulation focality using disc and ring electrode configurations: FEM analysis, J Neural Eng., 5, 163, 10.1088/1741-2560/5/2/007

Datta, 2009, Gyri-precise head model of transcranial direct current stimulation: improved spatial focality using a ring electrode versus conventional rectangular pad, Brain Stimul., 2, 201, 10.1016/j.brs.2009.03.005

Datta, 2011, Individualized model predicts brain current flow during transcranial direct-current stimulation treatment in responsive stroke patient, Brain Stimul., 4, 169, 10.1016/j.brs.2010.11.001

Dell'Osso, 2012, Transcranial direct current stimulation for the outpatient treatment of poor-responder depressed patients, Eur. Psychiatry, 27, 513, 10.1016/j.eurpsy.2011.02.008

Dijk, 2002, Integration of human sleep-wake regulation and circadian rhythmicity, J. Appl. Physiol., 92, 852, 10.1152/japplphysiol.00924.2001

Dmochowski, 2011, Optimized multi-electrode stimulation increases focality and intensity at target, J. Neural Eng., 8, 046011, 10.1088/1741-2560/8/4/046011

Dmochowski, 2013, Targeted transcranial direct current stimulation for rehabilitation after stroke, Neuroimage, 75, 12, 10.1016/j.neuroimage.2013.02.049

Dubljevic, 2014, The rising tide of tDCS in the media and academic literature, Neuron, 82, 731, 10.1016/j.neuron.2014.05.003

Edwards, 1993, Measurement of hemoglobin flow and blood flow by near-infrared spectroscopy, J. Appl. Physiol., 75, 1884, 10.1152/jappl.1993.75.4.1884

Edwards, 2013, Physiological and modeling evidence for focal transcranial electrical brain stimulation in humans: a basis for high-definition tDCS, Neuroimage, 74, 266, 10.1016/j.neuroimage.2013.01.042

Ferrucci, 2009, Transcranial direct current stimulation in severe, drug-resistant major depression, J. Affect. Disord., 118, 215, 10.1016/j.jad.2009.02.015

Filmer, 2014, Applications of transcranial direct current stimulation for understanding brain function, Trends Neurosci., 37, 742, 10.1016/j.tins.2014.08.003

Finn, 2015, Functional connectome fingerprinting: identifying individuals using patterns of brain connectivity, Nat Neurosci., 18, 1664, 10.1038/nn.4135

Fitzgerald, 2014, A negative pilot study of daily bimodal transcranial direct current stimulation in schizophrenia, Brain Stimul., 7, 813, 10.1016/j.brs.2014.08.002

Flöel, 2014, tDCS-enhanced motor and cognitive function in neurological diseases, Neuroimage, 85, 934, 10.1016/j.neuroimage.2013.05.098

Fox, 2006, Spontaneous neuronal activity distinguishes human dorsal and ventral attention systems, Proc. Natl. Acad. Sci. U. S. A., 103, 10046, 10.1073/pnas.0604187103

Fox, 2012, Efficacy of transcranial magnetic stimulation targets for depression is related to intrinsic functional connectivity with the subgenual cingulate, Biol. Psychiatry, 72, 595, 10.1016/j.biopsych.2012.04.028

Fox, 2014, Resting-state networks link invasive and noninvasive brain stimulation across diverse psychiatric and neurological diseases, Proc. Natl. Acad. Sci. U. S. A., 111, E4367, 10.1073/pnas.1405003111

Frank, 2012, Treatment of chronic tinnitus with repeated sessions of prefrontal transcranial direct current stimulation: outcomes from an open-label pilot study, J. Neurol., 259, 327, 10.1007/s00415-011-6189-4

Fregni, 2007, Technology insight: noninvasive brain stimulation in neurology-perspectives on the therapeutic potential of rTMS and tDCS, Nat. Clin. Pract. Neurol., 3, 383, 10.1038/ncpneuro0530

Fregni, 2006, A sham-controlled, phase II trial of transcranial direct current stimulation for the treatment of central pain in traumatic spinal cord injury, Pain, 122, 197, 10.1016/j.pain.2006.02.023

Fregni, 2006, Treatment of major depression with transcranial direct current stimulation, Bipolar Disord., 8, 203, 10.1111/j.1399-5618.2006.00291.x

Fregni, 2006, Cognitive effects of repeated sessions of transcranial direct current stimulation in patients with depression, Depress Anxiety, 23, 482, 10.1002/da.20201

Fregni, 2006, Noninvasive cortical stimulation with transcranial direct current stimulation in Parkinson's disease, Mov. Disord., 21, 1693, 10.1002/mds.21012

Fregni, 2006, A controlled clinical trial of cathodal DC polarization in patients with refractory epilepsy, Epilepsia, 47, 335, 10.1111/j.1528-1167.2006.00426.x

Galletta, 2015, Use of computational modeling to inform tDCS electrode montages for the promotion of language recovery in post-stroke aphasia, Brain Stimul., 10.1016/j.brs.2015.06.018

Gartside, 1968, Mechanisms of sustained increases of firing rate of neurons in the rat cerebral cortex after polarization: reverberating circuits or modification of synaptic conductance?, Nature, 220, 382, 10.1038/220382a0

Ghatan, 1995, Brain activation induced by the perceptual maze test: a PET study of cognitive performance, Neuroimage, 2, 112, 10.1006/nimg.1995.1014

Gilbert, 2007, Comment on Wandering minds: the default network and stimulus-independent thought, Science, 317, 43, 10.1126/science.1140801

Gusnard, 2001, Medial prefrontal cortex and self-referential mental activity: relation to a default mode of brain function, Proc. Natl. Acad. Sci. U. S. A., 98, 4259, 10.1073/pnas.071043098

Gusnard, 2001, Searching for a baseline: functional imaging and the resting human brain, Nat. Rev. Neurosci., 2, 685, 10.1038/35094500

Hahn, 2007, Cingulate activation increases dynamically with response speed under stimulus unpredictability, Cereb. Cortex, 17, 1664, 10.1093/cercor/bhl075

Hattori, 1990, Biphasic effects of polarizing current on adenosine-sensitive generation of cyclic AMP in rat cerebral cortex, Neurosci. Lett., 116, 320, 10.1016/0304-3940(90)90094-P

Herrmann, 2015, EEG oscillations: from correlation to causality, Int. J. Psychophysiol.

Hill, 2016, TMS-EEG: A window into the neurophysiological effects of transcranial electrical stimulation in non-motor brain regions, Neurosci. Biobehav. Rev., 64, 175, 10.1016/j.neubiorev.2016.03.006

Ho, 2014, A pilot study of alternative transcranial direct current stimulation electrode montages for the treatment of major depression, J. Affect. Disord., 167, 251, 10.1016/j.jad.2014.06.022

Hoy, 2015, The effect of transcranial Direct Current Stimulation on gamma activity and working memory in schizophrenia, Psychiatry Res, 228, 191, 10.1016/j.psychres.2015.04.032

Holland, 2011, Speech facilitation by left inferior frontal cortex stimulation, Curr. Biol., 21, 1403, 10.1016/j.cub.2011.07.021

Hone-Blanchet, 2015, Online effects of transcranial direct current stimulation in real time on human prefrontal and striatal metabolites, Biol. Psychiatry

Horvath, 2015, Evidence that transcranial direct current stimulation (tDCS) generates little-to-no reliable neurophysiologic effect beyond MEP amplitude modulation in healthy human subjects: a systematic review, Neuropsychologia, 66, 213, 10.1016/j.neuropsychologia.2014.11.021

Hutchison, 2013, Dynamic functional connectivity: promise, issues, and interpretations, Neuroimage, 80, 360, 10.1016/j.neuroimage.2013.05.079

Islam, 1995, Increase in the calcium level following anodal polarization in the rat brain, Brain Res., 684, 206, 10.1016/0006-8993(95)00434-R

Iwabuchi, 2015, Localized connectivity in depression: a meta-analysis of resting state functional imaging studies, Neurosci. Biobehav. Rev., 51, 77, 10.1016/j.neubiorev.2015.01.006

Iyer, 2005, Safety and cognitive effect of frontal DC brain polarization in healthy individuals, Neurology, 64, 872, 10.1212/01.WNL.0000152986.07469.E9

Jacobson, 2012, Modulating oscillatory brain activity correlates of behavioral inhibition using transcranial direct current stimulation, Clin. Neurophysiol., 123, 979, 10.1016/j.clinph.2011.09.016

Jausovec, 2014, Increasing working memory capacity with theta transcranial alternating current stimulation (tACS), Biol. Psychol., 96, 42, 10.1016/j.biopsycho.2013.11.006

Jung, 2013, COMETS: A MATLAB toolbox for simulating local electric fields generated by transcranial direct current stimulation (tDCS), Biomed. Eng. Lett., 3, 39, 10.1007/s13534-013-0087-x

Kaiser, 2015, Large-Scale network dysfunction in major depressive disorder: a meta-analysis of resting-State functional connectivity, JAMA Psychiatry, 72, 603, 10.1001/jamapsychiatry.2015.0071

Kalu, 2012, Transcranial direct current stimulation in the treatment of major depression: a meta-analysis, Psychol. Med., 42, 1791, 10.1017/S0033291711003059

Keeser, 2011, Prefrontal transcranial direct current stimulation changes connectivity of resting-state networks during fMRI, J. Neurosci., 31, 15284, 10.1523/JNEUROSCI.0542-11.2011

Keeser, 2011, Prefrontal direct current stimulation modulates resting EEG and event-related potentials in healthy subjects: a standardized low resolution tomography (sLORETA) study, Neuroimage, 55, 644, 10.1016/j.neuroimage.2010.12.004

Khanna, 2015, Microstates in resting-state EEG: current status and future directions, Neurosci. Biobehav. Rev., 49, 105, 10.1016/j.neubiorev.2014.12.010

Kirov, 2009, Slow oscillation electrical brain stimulation during waking promotes EEG theta activity and memory encoding, Proc. Natl. Acad. Sci. U. S. A., 106, 15460, 10.1073/pnas.0904438106

Kuo, 2014, Therapeutic effects of non-invasive brain stimulation with direct currents (tDCS) in neuropsychiatric diseases, Neuroimage, 85, 948, 10.1016/j.neuroimage.2013.05.117

Lafontaine, 2013, Transcranial direct current stimulation of the dorsolateral prefrontal cortex modulates repetition suppression to unfamiliar faces: an ERP study, PLoS One, 8, e81721, 10.1371/journal.pone.0081721

Laird, 2011, Behavioral interpretations of intrinsic connectivity networks, J. Cogn. Neurosci., 23, 4022, 10.1162/jocn_a_00077

Lang, 2005, How does transcranial DC stimulation of the primary motor cortex alter regional neuronal activity in the human brain?, Eur. J. Neurosci., 22, 495, 10.1111/j.1460-9568.2005.04233.x

Lewis, 2009, Learning sculpts the spontaneous activity of the resting human brain, Proc. Natl. Acad. Sci. U. S. A., 106, 17558, 10.1073/pnas.0902455106

Liebetanz, 2002, Pharmacological approach to the mechanisms of transcranial DC-stimulation-induced after-effects of human motor cortex excitability, Brain, 125, 2238, 10.1093/brain/awf238

Lohmann, 2010, Eigenvector centrality mapping for analyzing connectivity patterns in fMRI data of the human brain, PLoS One, 5, e10232, 10.1371/journal.pone.0010232

Loo, 2010, A double-blind, sham-controlled trial of transcranial direct current stimulation for the treatment of depression, Int. J. Neuropsychopharmacol., 13, 61, 10.1017/S1461145709990411

Loo, 2012, Transcranial direct current stimulation for depression: 3-week, randomised, sham-controlled trial, Br. J. Psychiatry, 200, 52, 10.1192/bjp.bp.111.097634

Lopez-Alonso, 2014, Inter-individual variability in response to non-invasive brain stimulation paradigms, Brain Stimul., 7, 372, 10.1016/j.brs.2014.02.004

Lopez-Alonso, 2015, Intra-individual variability in the response to anodal transcranial direct current stimulation, Clin. Neurophysiol., 126, 2342, 10.1016/j.clinph.2015.03.022

Lu, 2015, Spatiotemporal neural pattern similarity supports episodic memory, Curr. Biol., 25, 780, 10.1016/j.cub.2015.01.055

Maeoka, 2012, Influence of transcranial direct current stimulation of the dorsolateral prefrontal cortex on pain related emotions: a study using electroencephalographic power spectrum analysis, Neurosci. Lett., 512, 12, 10.1016/j.neulet.2012.01.037

Mangia, 2014, Transcranial direct current stimulation and power spectral parameters: a tDCS/EEG co-registration study, Front. Hum. Neurosci., 8, 601, 10.3389/fnhum.2014.00601

Manoli, 2012, Theoretical investigation of transcranial alternating current stimulation using realistic head model, Conf. Proc. IEEE Eng. Med. Biol. Soc., 2012, 4156

Margulies, 2010, Resting developments: a review of fMRI post-processing methodologies for spontaneous brain activity, MAGMA, 23, 289, 10.1007/s10334-010-0228-5

Marshall, 2004, Transcranial direct current stimulation during sleep improves declarative memory, J. Neurosci., 24, 9985, 10.1523/JNEUROSCI.2725-04.2004

Marshall, 2011, Transcranial electrical currents to probe EEG brain rhythms and memory consolidation during sleep in humans, PLoS One, 6, e16905, 10.1371/journal.pone.0016905

Martin, 2011, Fronto-extracephalic transcranial direct current stimulation as a treatment for major depression: an open-label pilot study, J. Affect. Disord., 134, 459, 10.1016/j.jad.2011.05.018

Martin, 2013, Continuation transcranial direct current stimulation for the prevention of relapse in major depression, J. Affect. Disord., 144, 274, 10.1016/j.jad.2012.10.012

Mazoyer, 2009, Regional cerebral blood flow increases during wakeful rest following cognitive training, Brain Res. Bull., 80, 133, 10.1016/j.brainresbull.2009.06.021

Meinzer, 2012, Electrical brain stimulation improves cognitive performance by modulating functional connectivity and task-specific activation, J. Neurosci., 32, 1859, 10.1523/JNEUROSCI.4812-11.2012

Meinzer, 2013, Anodal transcranial direct current stimulation temporarily reverses age-associated cognitive decline and functional brain activity changes, J. Neurosci., 33, 12470, 10.1523/JNEUROSCI.5743-12.2013

Meinzer, 2014, Transcranial direct current stimulation in mild cognitive impairment: behavioral effects and neural mechanisms, Alzheimers Dement

Merzagora, 2010, Prefrontal hemodynamic changes produced by anodal direct current stimulation, Neuroimage, 49, 2304, 10.1016/j.neuroimage.2009.10.044

Miller, 2015, Anodal transcranial direct current stimulation (tDCS) increases frontal-midline theta activity in the human EEG: a preliminary investigation of non-invasive stimulation, Neurosci. Lett., 588, 114, 10.1016/j.neulet.2015.01.014

Miranda, 2006, Modeling the current distribution during transcranial direct current stimulation, Clin. Neurophysiol., 117, 1623, 10.1016/j.clinph.2006.04.009

Miranda, 2006, Modeling the current distribution during transcranial direct current stimulation, Clin. Neurophysiol., 117, 1623, 10.1016/j.clinph.2006.04.009

Monte-Silva, 2013, Induction of late LTP-like plasticity in the human motor cortex by repeated non-invasive brain stimulation, Brain Stimul., 6, 424, 10.1016/j.brs.2012.04.011

Montez, 2009, Altered temporal correlations in parietal alpha and prefrontal theta oscillations in early-stage Alzheimer disease, Proc. Natl. Acad. Sci. U. S. A., 106, 1614, 10.1073/pnas.0811699106

Nakamura-Palacios, 2012, Auditory event-related potentials (P3) and cognitive changes induced by frontal direct current stimulation in alcoholics according to Lesch alcoholism typology, Int. J. Neuropsychopharmacol., 15, 601, 10.1017/S1461145711001040

Nawani, 2014, Modulation of corollary discharge dysfunction in schizophrenia by tDCS: preliminary evidence, Brain Stimul., 7, 486, 10.1016/j.brs.2014.01.003

Nelson, 2014, Enhancing vigilance in operators with prefrontal cortex transcranial direct current stimulation (tDCS), Neuroimage, 85, 909, 10.1016/j.neuroimage.2012.11.061

Neuling, 2012, Finite-element model predicts current density distribution for clinical applications of tDCS and tACS, Front. Psychiatry, 3, 83, 10.3389/fpsyt.2012.00083

Nihonsugi, 2015, Selective increase of intention-based economic decisions by noninvasive brain stimulation to the dorsolateral prefrontal cortex, J. Neurosci., 35, 3412, 10.1523/JNEUROSCI.3885-14.2015

Nitsche, 2000, Excitability changes induced in the human motor cortex by weak transcranial direct current stimulation, J. Physiol., 527, 633, 10.1111/j.1469-7793.2000.t01-1-00633.x

Nitsche, 2001, Sustained excitability elevations induced by transcranial DC motor cortex stimulation in humans, Neurology, 57, 1899, 10.1212/WNL.57.10.1899

Nitsche, 2003, Pharmacological modulation of cortical excitability shifts induced by transcranial direct current stimulation in humans, J. Physiol., 553, 293, 10.1113/jphysiol.2003.049916

Nitsche, 2003, Modulation of cortical excitability by weak direct current stimulation–technical, safety and functional aspects, Suppl. Clin. Neurophysiol., 56, 255, 10.1016/S1567-424X(09)70230-2

Nitsche, 2003, Safety criteria for transcranial direct current stimulation (tDCS) in humans, Clin. Neurophysiol., 114, 2220, 10.1016/S1388-2457(03)00235-9

Nitsche, 2003, Level of action of cathodal DC polarisation induced inhibition of the human motor cortex, Clin. Neurophysiol., 114, 600, 10.1016/S1388-2457(02)00412-1

Nitsche, 2003, Facilitation of implicit motor learning by weak transcranial direct current stimulation of the primary motor cortex in the human, J. Cogn. Neurosci., 15, 619, 10.1162/089892903321662994

Nitsche, 2004, Consolidation of human motor cortical neuroplasticity by D-cycloserine, Neuropsychopharmacology, 29, 1573, 10.1038/sj.npp.1300517

Nitsche, 2005, Modulating parameters of excitability during and after transcranial direct current stimulation of the human motor cortex, J. Physiol., 568, 291, 10.1113/jphysiol.2005.092429

Nitsche, 2008, Transcranial direct current stimulation: state of the art 2008, Brain Stimul., 1, 206, 10.1016/j.brs.2008.06.004

Ohn, 2008, Time-dependent effect of transcranial direct current stimulation on the enhancement of working memory, Neuroreport, 19, 43, 10.1097/WNR.0b013e3282f2adfd

Palm, 2012, Transcranial direct current stimulation in treatment resistant depression: a randomized double-blind, placebo-controlled study, Brain Stimul., 5, 242, 10.1016/j.brs.2011.08.005

Palm, 2013, Prefrontal transcranial direct current stimulation (tDCS) changes negative symptoms and functional connectivity MRI (fcMRI) in a single case of treatment-resistant schizophrenia, Schizophr. Res., 150, 583, 10.1016/j.schres.2013.08.043

Park, 2013, Transcranial direct current stimulation increases resting state interhemispheric connectivity, Neurosci. Lett., 539, 7, 10.1016/j.neulet.2013.01.047

Paulus, 2004, Outlasting excitability shifts induced by direct current stimulation of the human brain, Suppl. Clin. Neurophysiol., 57, 708, 10.1016/S1567-424X(09)70411-8

Pena-Gomez, 2012, Modulation of large-scale brain networks by transcranial direct current stimulation evidenced by resting-state functional MRI, Brain Stimul., 5, 252, 10.1016/j.brs.2011.08.006

Pereira, 2013, Modulation of verbal fluency networks by transcranial direct current stimulation (tDCS) in Parkinson's disease, Brain Stimul., 6, 16, 10.1016/j.brs.2012.01.006

Plewnia, 2015, Keep calm and carry on: improved frustration tolerance and processing speed by transcranial direct current stimulation (tDCS), PLoS One, 10, e0122578, 10.1371/journal.pone.0122578

Polania, 2012, The importance of timing in segregated theta phase-coupling for cognitive performance, Curr Biol., 22, 1314, 10.1016/j.cub.2012.05.021

Powell, 2014, Modulation of cortical activity by transcranial direct current stimulation in patients with affective disorder, PLoS One, 9, e98503, 10.1371/journal.pone.0098503

Prehn-Kristensen, 2014, 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., 7, 793, 10.1016/j.brs.2014.07.036

Purpura, 1965, Intracellular activities and evoked potential changes during polarization of motor cortex, J. Neurophysiol., 28, 166, 10.1152/jn.1965.28.1.166

Purpura, 1965, Intracellular activities and evoked potential changes during polarization of motor cortex, J. Neurophysiol., 28, 10.1152/jn.1965.28.1.166

Reato, 2013, Transcranial electrical stimulation accelerates human sleep homeostasis, PLoS Comput Biol., 9, e1002898, 10.1371/journal.pcbi.1002898

Rae, 2013, Anodal transcranial direct current stimulation increases brain intracellular pH and modulates bioenergetics, Int. J. Neuropsychopharmacol., 16, 1695, 10.1017/S1461145713000084

Rango, 2008, Myoinositol content in the human brain is modified by transcranial direct current stimulation in a matter of minutes: a 1H-MRS study, Magn. Reson. Med., 60, 782, 10.1002/mrm.21709

Reinhart, 2014, Causal control of medial-frontal cortex governs electrophysiological and behavioral indices of performance monitoring and learning, J. Neurosci., 34, 4214, 10.1523/JNEUROSCI.5421-13.2014

Reinhart, 2015, Enhancing long-term memory with stimulation tunes visual attention in one trial, Proc. Natl. Acad. Sci. U. S. A., 112, 625, 10.1073/pnas.1417259112

Reinhart, 2015, Synchronizing theta oscillations with direct-current stimulation strengthens adaptive control in the human brain, Proc. Natl. Acad. Sci U. S. A., 112, 9448, 10.1073/pnas.1504196112

Rigonatti, 2008, Transcranial direct stimulation and fluoxetine for the treatment of depression, Eur. Psychiatry, 23, 74, 10.1016/j.eurpsy.2007.09.006

Rosenkranz, 2000, Diminution of training-induced transient motor cortex plasticity by weak transcranial direct current stimulation in the human, Neurosci. Lett., 296, 61, 10.1016/S0304-3940(00)01621-9

Rosso, 2014, Connectivity between right inferior frontal gyrus and supplementary motor area predicts after-effects of right frontal cathodal tDCS on picture naming speed, Brain Stimul., 7, 122, 10.1016/j.brs.2013.08.007

Ruohonen, 2012, tDCS possibly stimulates glial cells, Clin. Neurophysiol., 123, 2006, 10.1016/j.clinph.2012.02.082

Sehm, 2013, A novel ring electrode setup for the recording of somatosensory evoked potentials during transcranial direct current stimulation (tDCS), J. Neurosci. Methods, 212, 234, 10.1016/j.jneumeth.2012.10.006

Seibt, 2015, The pursuit of DLPFC: non-neuronavigated methods to target the left dorsolateral pre-frontal cortex with symmetric bicephalic transcranial direct current stimulation (tDCS), Brain Stimul., 10.1016/j.brs.2015.01.401

Shulman, 1997, Common blood flow changes across visual tasks: II. decreases in cerebral cortex, J. Cogn. Neurosci., 9, 648, 10.1162/jocn.1997.9.5.648

Singer, 2013, Cortical dynamics revisited, Trends Cogn. Sci., 17, 616, 10.1016/j.tics.2013.09.006

Smit, 2013, Long-range temporal correlations in resting-state alpha oscillations predict human timing-error dynamics, J. Neurosci., 33, 11212, 10.1523/JNEUROSCI.2816-12.2013

Snowball, 2013, Long-term enhancement of brain function and cognition using cognitive training and brain stimulation, Curr. Biol., 23, 987, 10.1016/j.cub.2013.04.045

Sporns, 2004, Organization, development and function of complex brain networks, Trends Cogn. Sci., 8, 418, 10.1016/j.tics.2004.07.008

Stagg, 2011, Physiological basis of transcranial direct current stimulation, Neuroscientist, 17, 37, 10.1177/1073858410386614

Stagg, 2009, Polarity-sensitive modulation of cortical neurotransmitters by transcranial stimulation, J. Neurosci., 29, 5202, 10.1523/JNEUROSCI.4432-08.2009

Stagg, 2013, Widespread modulation of cerebral perfusion induced during and after transcranial direct current stimulation applied to the left dorsolateral prefrontal cortex, J. Neurosci., 33, 11425, 10.1523/JNEUROSCI.3887-12.2013

Thibaut, 2014, tDCS in patients with disorders of consciousness: sham-controlled randomized double-blind study, Neurology, 82, 1112, 10.1212/WNL.0000000000000260

Tremblay, 2014, The uncertain outcome of prefrontal tDCS, Brain Stimul., 7, 773, 10.1016/j.brs.2014.10.003

Turken, 2008, Cognitive processing speed and the structure of white matter pathways: convergent evidence from normal variation and lesion studies, Neuroimage, 42, 1032, 10.1016/j.neuroimage.2008.03.057

Ulam, 2014, Cumulative effects of transcranial direct current stimulation on EEG oscillations and attention/working memory during subacute neurorehabilitation of traumatic brain injury, Clin. Neurophysiol.

Utz, 2010, Electrified minds: transcranial direct current stimulation (tDCS) and galvanic vestibular stimulation (GVS) as methods of non-invasive brain stimulation in neuropsychology-a review of current data and future implications, Neuropsychologia, 48, 2789, 10.1016/j.neuropsychologia.2010.06.002

Valle, 2009, Efficacy of anodal transcranial direct current stimulation (tDCS) for the treatment of fibromyalgia: results of a randomized, shamcontrolled longitudinal clinical trial, J. Pain Manag., 2, 353

Vanneste, 2011, Bifrontal transcranial direct current stimulation modulates tinnitus intensity and tinnitus-distress-related brain activity, Eur. J. Neurosci., 34, 605, 10.1111/j.1460-9568.2011.07778.x

Vanneste, 2010, Bilateral dorsolateral prefrontal cortex modulation for tinnitus by transcranial direct current stimulation: a preliminary clinical study, Exp. Brain Res., 202, 779, 10.1007/s00221-010-2183-9

Vanneste, 2011, Different resting state brain activity and functional connectivity in patients who respond and not respond to bifrontal tDCS for tinnitus suppression, Exp. Brain Res., 210, 217, 10.1007/s00221-011-2617-z

van den Heuvel, 2010, Specific somatotopic organization of functional connections of the primary motor network during resting state, Hum. Brain Mapp., 31, 631, 10.1002/hbm.20893

van Waarde, 2015, A functional MRI marker may predict the outcome of electroconvulsive therapy in severe and treatment-resistant depression, Mol. Psychiatry, 20, 609, 10.1038/mp.2014.78

van den Heuvel, 2013, An anatomical substrate for integration among functional networks in human cortex, J. Neurosci., 33, 14489, 10.1523/JNEUROSCI.2128-13.2013

Vercammen, 2011, Transcranial direct current stimulation influences probabilistic association learning in schizophrenia, Schizophr. Res., 131, 198, 10.1016/j.schres.2011.06.021

Volpato, 2013, Modulation of affective symptoms and resting state activity by brain stimulation in a treatment-resistant case of obsessive-compulsive disorder, Neurocase, 19, 360, 10.1080/13554794.2012.667131

Voss, 2014, Induction of self awareness in dreams through frontal low current stimulation of gamma activity, Nat. Neurosci., 17, 810, 10.1038/nn.3719

Wagner, 2007, Noninvasive human brain stimulation, Annu. Rev. Biomed. Eng., 9, 527, 10.1146/annurev.bioeng.9.061206.133100

Watts, 1998, Collective dynamics of ‘small-world' networks, Nature, 393, 440, 10.1038/30918

Weaver, 1976, Current density in bilateral and unilateral ECT, Biol. Psychiatry, 11, 303

Weber, 2014, Prefrontal transcranial direct current stimulation alters activation and connectivity in cortical and subcortical reward systems: a tDCS-fMRI study, Hum. Brain Mapp., 35, 3673, 10.1002/hbm.22429

Wirth, 2011, Effects of transcranial direct current stimulation (tDCS) on behaviour and electrophysiology of language production, Neuropsychologia, 49, 3989, 10.1016/j.neuropsychologia.2011.10.015

Wolkenstein, 2013, Amelioration of cognitive control in depression by transcranial direct current stimulation, Biol. Psychiatry, 73, 646, 10.1016/j.biopsych.2012.10.010

Woods, 2015, Effects of electrode drift in transcranial direct current stimulation, Brain Stimul., 8, 515, 10.1016/j.brs.2014.12.007

Xue, 2012, Lateral prefrontal cortex contributes to maladaptive decisions, Proc. Natl. Acad. Sci. U. S. A., 109, 4401, 10.1073/pnas.1111927109

Zaehle, 2011, Transcranial direct current stimulation of the prefrontal cortex modulates working memory performance: combined behavioural and electrophysiological evidence, BMC Neurosci., 12, 2, 10.1186/1471-2202-12-2

Zaghi, 2010, Noninvasive brain stimulation with low-intensity electrical currents: putative mechanisms of action for direct and alternating current stimulation, Neuroscientist, 16, 285, 10.1177/1073858409336227

Zalesky, 2014, Time-resolved resting-state brain networks, Proc. Natl. Acad. Sci. U. S. A., 111, 10341, 10.1073/pnas.1400181111

Zuo, 2012, Network centrality in the human functional connectome, Cereb. Cortex, 22, 1862, 10.1093/cercor/bhr269