Bifrontal tDCS prevents implicit learning acquisition in antidepressant-free patients with major depressive disorder

Author(s)

Brunoni, Andre Russowsky ^{[1, 2]} ; Zanao, Tamires Araujo ^{[1, 2]} ; Ferrucci, Roberta ^[3] ; Priori, Alberto ^[3] ; Valiengo, Leandro ^{[1, 2]} ; de Oliveira, Janaina Farias ^{[1, 2]} ; Boggio, Paulo S. ^{[4, 5]} ; Lotufo, Paulo A. ^[1] ; Bensenor, Isabela M. ^[1] ; Fregni, Felipe ^[6]

Affiliation

^[1] Univ Sao Paulo, Univ Hosp, Clin Res Ctr, BR-05508 Sao Paulo - Brazil

^[2] Univ Sao Paulo, Inst Psychol, Dept Neurosci & Behav, BR-05508 Sao Paulo - Brazil

^[3] Univ Milan, Ctr Clin Neurostimolaz Neurotecnol & Disordini Mo, Fdn IRCCS Ca Granda, Dipartimento Fisiopatol Med Chirurg & Trapianti, I-20122 Milan - Italy

^[4] Univ Prebiteriana Mackenzie, Ctr Hlth & Biol Sci, Social & Cognit Neurosci Lab, Sao Paulo - Brazil

^[5] Univ Prebiteriana Mackenzie, Ctr Hlth & Biol Sci, Dev Disorders Program, Sao Paulo - Brazil

^[6] Harvard Univ, Sch Med, Spaulding Rehabil Hosp, Lab Neuromodulat, Boston, MA - USA

• Document type: Journal article
• Source: PROGRESS IN NEURO-PSYCHOPHARMACOLOGY & BIOLOGICAL PSYCHIATRY; v. 43, p. 146-150, JUN 3 2013.
• Web of Science Citations: 14

Abstract

The findings for implicit (procedural) learning impairment in major depression are mixed. We investigated this issue using transcranial direct current stimulation (tDCS), a method that non-invasively increases/decreases cortical activity. Twenty-eight age- and gender-matched, antidepressant-free depressed subjects received a single-session of active/sham tDCS. We used a bifrontal setup - anode and cathode over the left and the right dorsolateral prefrontal cortex (DLPFC), respectively. The probabilistic classification-learning (PCL) task was administered before and during tDCS. The percentage of correct responses improved during sham; although not during active tDCS. Procedural or implicit learning acquisition between tasks also occurred only for sham. We discuss whether DLPFC activation decreased activity in subcortical structures due to the depressive state, The deactivation of the right DLPFC by cathodal tDCS can also account for our results. To conclude, active bifrontal tDCS prevented implicit learning in depressive patients. Further studies with different tDCS montages and in other samples are necessary. (C) 2012 Elsevier Inc. All rights reserved. (AU)

• FAPESP's process: 11/00212-2 - A randomized, double-blinded, placebo-controlled clinical trial using transcranial direct current stimulation and sertraline for evaluation of cognitive-affective behavior in major depressive disorder
• Grantee: Tamires Araujo Zanão Mariano
• Support Opportunities: Scholarships in Brazil - Scientific Initiation