title: Anodal Stimulation of the Left DLPFC Increases IGT Scores and Decreases Delay Discounting Rate in Healthy Males.
abstract: Previous correlational imaging studies have implicated the dorsolateral prefrontal cortex (DLPFC) in decision making. Using High-Definition Transcranial Direct Current Stimulation (HD-tDCS), the present study directly investigated the causal role of the DLPFC in performing the Iowa Gambling Task (IGT) and the Inter-Temporal Choice (ITC) task. Three experiments were conducted: Experiment 1 (N= 41) to study the left DLPFC, Experiment 2 (N= 49) to study the right DLPFC, and Experiment 3 (N= 20, a subset of those in Experiment 1) to switch the experimental and control conditions. All participants were healthy male college students. For Experiments 1 and 2, participants were randomly assigned to either the HD-tDCS or the sham stimulation condition. For Experiment 3, participants were assigned to the condition they were not in during Experiment 1. Results showed that HD-tDCS over the left DLPFC increased IGT score, decreased the recency parameter in IGT, and lowered delay discounting rate (k) in the ITC task. We discussed the potential roles of impulse control and time perception in mediating the effect of tDCS stimulation of left DLPFC on decision making. Our results have clinical implications for the treatment of disorders involving poor decision-making, such as addictions.
authors.affiliation: Decision Neuroscience Lab, Faculty of Psychology, Southwest UniversityChongqing, China; Key Laboratory of Cognition and Personality, Ministry of Education, Southwest UniversityChongqing, China; Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of SciencesBeijing, China; Southwest University Branch, Collaborative Innovation Center of Assessment Toward Basic Education Quality at Beijing Normal UniversityChongqing, China.
authors.forename: Qinghua
authors.initials: Q
authors.lastname: He
authors.affiliation: Decision Neuroscience Lab, Faculty of Psychology, Southwest UniversityChongqing, China; Key Laboratory of Cognition and Personality, Ministry of Education, Southwest UniversityChongqing, China.
authors.forename: Mei
authors.initials: M
authors.lastname: Chen
authors.affiliation: Department of Psychology and Social Behavior, University of California at Irvine, Irvine CA, USA.
authors.forename: Chuansheng
authors.initials: C
authors.lastname: Chen
authors.affiliation: National Key Laboratory of Cognitive Neuroscience and Learning, IDG/McGovern Institute for Brain Research, Beijing Normal University Beijing, China.
authors.forename: Gui
authors.initials: G
authors.lastname: Xue
authors.affiliation: Decision Neuroscience Lab, Faculty of Psychology, Southwest UniversityChongqing, China; Key Laboratory of Cognition and Personality, Ministry of Education, Southwest UniversityChongqing, China.
authors.forename: Tingyong
authors.initials: T
authors.lastname: Feng
authors.affiliation: Brain and Creativity Institute and Department of Psychology, University of Southern California, Los Angeles CA, USA.
authors.forename: Antoine
authors.initials: A
authors.lastname: Bechara
keywords: DLPFC; HD-tDCS; IGT; decision making; inter-temporal choice task