Transcranial Direct Current Stimulation (tDCS)/Transcranial Alternating Current Stimulation (tACS) Original Article| Volume 6, ISSUE 4, P660-667, July 2013

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The Effects of Cross-Hemispheric Dorsolateral Prefrontal Cortex Transcranial Direct Current Stimulation (tDCS) on Task Switching

Published:November 05, 2012DOI:



      Task switching, defined as the ability to flexibly switch between tasks in the face of goal shifting, is a central mechanism in cognitive control. Task switching is thought to involve both prefrontal cortex (PFC) and parietal regions. Our previous work has shown that it is possible to modulate set shifting tasks using 1 mA tDCS on both the left dorsolateral prefrontal cortex and the left primary motor area. However, it remains unclear whether the effects of PFC tDCS on task switching are hemisphere-dependent.


      We aimed to test the effects of three types of cross-hemispheric tDCS over the PFC (left anode–right cathode [LA-RC], left cathode–right anode [LC-RA] and sham stimulation) on participants' performance (reaction time) and accuracy (correct responses) in two task-switching paradigms (i.e., letter/digit naming and vowel–consonant/parity tasks).


      Sixteen participants received cross-hemispheric tDCS over the PFC in two task-switching paradigms.


      The results show that cross-hemispheric tDCS over the PFC modulates task-switching ability in both paradigms. Our results were task and hemisphere-specific, such that in the letter/digit naming task, LA-RC tDCS increased switching performance, whereas LC-RA tDCS improved accuracy. On the other hand, in the vowel–consonant/parity task, LA-RC improved accuracy, and decreased switching performance.


      Our findings confirm the notion that involvement of the PFC on task switching depends critically on laterality, implying the existence of different roles for the left hemisphere and the right hemisphere in task switching.


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        • Brass M.
        • von Cramon D.Y.
        Decomposing components of task preparation with functional magnetic resonance imaging.
        J Cogn Neurosci. 2004; 16: 609-620
        • Monsell S.
        Task switching.
        Trends Cogn Sci. 2003; 7: 134-140
        • Dreher J.C.
        • Grafman J.
        Dissociating the roles of the rostral anterior cingulate and the lateral prefrontal cortices in performing two tasks simultaneously or successively.
        Cereb Cortex. 2003; 13: 329-339
        • Nagahama Y.
        • Okada T.
        • Katsumi Y.
        • Hayashi T.
        • Yamauchi H.
        • Oyanagi C.
        • et al.
        Dissociable mechanisms of attentional control within the human prefrontal cortex.
        Cereb Cortex. 2001; 11: 85-92
        • Ravizza S.M.
        • Carter C.S.
        Shifting set about task switching: behavioral and neural evidence for distinct forms of cognitive flexibility.
        Neuropsychologia. 2008; 46: 2924-2935
        • Barber A.D.
        • Carter C.S.
        Cognitive control involved in overcoming prepotent response tendencies and switching between tasks.
        Cereb Cortex. 2005; 15: 899-912
        • Aron A.R.
        • Monsell S.
        • Sahakian B.J.
        • Robbins T.W.
        A componential analysis of task-switching deficits associated with lesions of left and right frontal cortex.
        Brain. 2004; 127: 1561-1573
        • Sohn M.H.
        • Ursu S.
        • Anderson J.R.
        • Stenger V.A.
        • Carter C.S.
        The role of prefrontal cortex and posterior parietal cortex in task switching.
        Proc Natl Acad Sci U S A. 2000; 97: 13448-13453
        • Leite J.
        • Carvalho S.
        • Fregni F.
        • Gonçalves Ó.F.
        Task-specific effects of tDCS-induced cortical excitability changes on cognitive and motor sequence set shifting performance.
        PLoS One. 2011; 6: e24140
        • D'Esposito M.
        • Cooney J.W.
        • Gazzaley A.
        • Gibbs S.E.
        • Postle B.R.
        Is the prefrontal cortex necessary for delay task performance? Evidence from lesion and FMRI data.
        J Int Neuropsychol Soc. 2006; 12: 248-260
        • Gazzaniga M.S.
        Cerebral specialization and interhemispheric communication: does the corpus callosum enable the human condition?.
        Brain. 2000; 123: 1293-1326
        • Goel V.
        • Vartanian O.
        Dissociating the roles of right ventral lateral and dorsal lateral prefrontal cortex in generation and maintenance of hypotheses in set-shift problems.
        Cereb Cortex. 2005; 15: 1170-1177
        • Goel V.
        • Tierney M.
        • Sheesley L.
        • Bartolo A.
        • Vartanian O.
        • Grafman J.
        Hemispheric specialization in human prefrontal cortex for resolving certain and uncertain inferences.
        Cereb Cortex. 2007; 17: 2245-2250
        • Fregni F.
        • Boggio P.
        • Nitsche M.
        • Bermpohl F.
        • Antal A.
        • Feredoes E.
        • et al.
        Anodal transcranial direct current stimulation of prefrontal cortex enhances working memory.
        Exp Brain Res. 2005; 166: 23-30
        • Rypma B.
        • D'Esposito M.
        The roles of prefrontal brain regions in components of working memory: effects of memory load and individual differences.
        Proc Natl Acad Sci U S A. 1999; 96: 6558-6563
        • Nitsche M.A.
        • Paulus W.
        Sustained excitability elevations induced by transcranial DC motor cortex stimulation in humans.
        Neurology. 2001; 57: 1899-1901
        • Ardolino G.
        • Bossi B.
        • Barbieri S.
        • Priori A.
        Non-synaptic mechanisms underlie the after-effects of cathodal transcutaneous direct current stimulation of the human brain.
        J Physiol. 2005; 568: 653-663
        • Boggio P.S.
        • Fregni F.
        • Valasek C.
        • Ellwood S.
        • Chi R.
        • Gallate J.
        • et al.
        Temporal lobe cortical electrical stimulation during the encoding and retrieval phase reduces false memories.
        PLoS One. 2009; 4: e4959
        • Nitsche M.A.
        • Paulus W.
        Excitability changes induced in the human motor cortex by weak transcranial direct current stimulation.
        J Physiol. 2000; 527: 633-639
        • Jasper H.
        The ten-twenty electrode system of the International Federation.
        Electroencephalogr Clin Neurophysiol Suppl. 1958; 10: 371-375
        • Jensen O.
        • Gelfand J.
        • Kounios J.
        • Lisman J.E.
        Oscillations in the alpha band (9–12 Hz) increase with memory load during retention in a short-term memory task.
        Cereb Cortex. 2002; 12: 877-882
        • Hecht D.
        • Walsh V.
        • Lavidor M.
        Transcranial direct current stimulation facilitates decision making in a probabilistic guessing task.
        J Neurosci. 2010; 30: 4241-4245
        • Fecteau S.
        • Knoch D.
        • Fregni F.
        • Sultani N.
        • Boggio P.
        • Pascual-Leone A.
        Diminishing risk-taking behavior by modulating activity in the prefrontal cortex: a direct current stimulation study.
        J Neurosci. 2007; 27: 12500-12505
        • Fregni F.
        • Orsati F.
        • Pedrosa W.
        • Fecteau S.
        • Tome F.A.
        • Nitsche M.A.
        • et al.
        Transcranial direct current stimulation of the prefrontal cortex modulates the desire for specific foods.
        Appetite. 2008; 51: 34-41
        • Boggio P.S.
        • Sultani N.
        • Fecteau S.
        • Merabet L.
        • Mecca T.
        • Pascual-Leone A.
        • et al.
        Prefrontal cortex modulation using transcranial DC stimulation reduces alcohol craving: a double-blind, sham-controlled study.
        Drug Alcohol Depend. 2008; 92: 55-60
        • Wolford G.
        • Miller M.B.
        • Gazzaniga M.
        The left hemisphere's role in hypothesis formation.
        J Neurosci. 2000; 20: RC64
        • Walsh V.
        Hemispheric asymmetries: a brain in two minds.
        Curr Biol. 2000; 10: R460-R462
        • Wagner T.
        • Fregni F.
        • Fecteau S.
        • Grodzinsky A.
        • Zahn M.
        • Pascual-Leone A.
        Transcranial direct current stimulation: a computer-based human model study.
        NeuroImage. 2007; 35: 1113-1124
        • Miranda P.C.
        • Lomarev M.
        • Hallett M.
        Modeling the current distribution during transcranial direct current stimulation.
        Clin Neurophysiol. 2006; 117: 1623-1629
        • Aron A.R.
        • Robbins T.W.
        • Poldrack R.A.
        Inhibition and the right inferior frontal cortex.
        Trends Cogn Sci. 2004; 8: 170-177
        • Jacobson L.
        • Javitt D.C.
        • Lavidor M.
        Activation of inhibition: diminishing impulsive behavior by direct current stimulation over the inferior frontal gyrus.
        J Cogn Neurosci. 2011; 23: 3380-3387
        • Husain M.
        • Nachev P.
        Space and the parietal cortex.
        Trends Cogn Sci. 2007; 11: 30-36
        • Corbetta M.
        • Patel G.
        • Shulman G.L.
        The reorienting system of the human brain: from environment to theory of mind.
        Neuron. 2008; 58: 306-324
        • Bode S.
        • Haynes J.D.
        Decoding sequential stages of task preparation in the human brain.
        NeuroImage. 2009; 45: 606-613
        • Stone D.B.
        • Tesche C.D.
        Transcranial direct current stimulation modulates shifts in global/local attention.
        NeuroReport. 2009; 20: 1115-1119
        • Kamigaki T.
        • Fukushima T.
        • Miyashita Y.
        Neuronal signal dynamics during preparation and execution for behavioral shifting in macaque posterior parietal cortex.
        J Cogn Neurosci. 2011; 23: 2503-2520
        • Yamasaki H.
        • LaBar K.S.
        • McCarthy G.
        Dissociable prefrontal brain systems for attention and emotion.
        Proc Natl Acad Sci U S A. 2002; 99: 11447-11451
        • Ruthruff E.
        • Remington R.W.
        • Johnston J.C.
        Switching between simple cognitive tasks: the interaction of top-down and bottom-up factors.
        J Exp Psychol Hum Percept Perform. 2001; 27: 1404-1419
        • Rubinstein J.S.
        • Meyer D.E.
        • Evans J.E.
        Executive control of cognitive processes in task switching.
        J Exp Psychol Hum Percept Perform. 2001; 27: 763-797