title: Conflict acts as an implicit cost in reinforcement learning.
abstract: Conflict has been proposed to act as a cost in action selection, implying a general function of medio-frontal cortex in the adaptation to aversive events. Here we investigate if response conflict acts as a cost during reinforcement learning by modulating experienced reward values in cortical and striatal systems. Electroencephalography recordings show that conflict diminishes the relationship between reward-related frontal theta power and cue preference yet it enhances the relationship between punishment and cue avoidance. Individual differences in the cost of conflict on reward versus punishment sensitivity are also related to a genetic polymorphism associated with striatal D1 versus D2 pathway balance (DARPP-32). We manipulate these patterns with the D2 agent cabergoline, which induces a strong bias to amplify the aversive value of punishment outcomes following conflict. Collectively, these findings demonstrate that interactive cortico-striatal systems implicitly modulate experienced reward and punishment values as a function of conflict.
authors.affiliation: Department of Psychology, University of New Mexico, Logan Hall, 1 University of New Mexico, MSC03 2220, Albuquerque, New Mexico 87131, USA.
authors.forename: James F
authors.initials: JF
authors.lastname: Cavanagh
authors.affiliation: Department of Cognitive, Linguistic and Psychological Sciences, Brown University, 190 Thayer Street, Providence, Rhode Island 02912-1821, USA.
authors.forename: Sean E
authors.initials: SE
authors.lastname: Masters
authors.affiliation: Department of Neuroscience, Brown University, Box GL-N, Providence, Rhode Island 02912-1821, USA.
authors.forename: Kevin
authors.initials: K
authors.lastname: Bath
authors.affiliation: 1] Department of Cognitive, Linguistic and Psychological Sciences, Brown University, 190 Thayer Street, Providence, Rhode Island 02912-1821, USA [2] Department of Psychiatry, Brown University, Box G-A1, Providence, Rhode Island 02912, USA [3] Brown Institute for Brain Science, Brown University, Box 1953 2 Stimson Ave., Providence, Rhode Island 02912, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Frank
mesh_terms: D000293:Adolescent; D000328:Adult; D000077465:Cabergoline; D003220:Conflict, Psychological; D003463:Cues; D004298:Dopamine / Q000378:metabolism; D018491:Dopamine Agonists; D051937:Dopamine and cAMP-Regulated Phosphoprotein 32 / Q000235:genetics; D004873:Ergolines; D005133:Eye Movements; D005260:Female; D006801:Humans; D008297:Male; D012054:Reinforcement, Psychology; D013826:Theta Rhythm; D055815:Young Adult
chemical_list: D018491:Dopamine Agonists; D051937:Dopamine and cAMP-Regulated Phosphoprotein 32; D004873:Ergolines; C497928:PPP1R1B protein, human; D000077465:Cabergoline; D004298:Dopamine