title: Abnormal modulation of reward versus punishment learning by a dopamine D2-receptor antagonist in pathological gamblers.
abstract: BACKGROUND
  Pathological gambling has been associated with dopamine transmission abnormalities, in particular dopamine D2-receptor deficiency, and reversal learning deficits. Moreover, pervasive theoretical accounts suggest a key role for dopamine in reversal learning. However, there is no empirical evidence for a direct link between dopamine, reversal learning and pathological gambling.
  
  
  OBJECTIVE
  The aim of the present study is to triangulate dopamine, reversal learning, and pathological gambling.
  
  
  METHODS
  Here, we assess the hypothesis that pathological gambling is accompanied by dopamine-related problems with learning from reward and punishment by investigating effects of the dopamine D2-receptor antagonist sulpiride (400 mg) on reward- and punishment-based reversal learning in 18 pathological gamblers and 22 healthy controls, using a placebo-controlled, double-blind, counter-balanced design.
  
  
  RESULTS
  In line with previous studies, blockade of D2 receptors with sulpiride impaired reward versus punishment reversal learning in controls. By contrast, sulpiride did not have any outcome-specific effects in gamblers.
  
  
  CONCLUSIONS
  These data demonstrate that pathological gambling is associated with a dopamine-related anomaly in reversal learning from reward and punishment.
authors.affiliation: Donders Institute for Brain, Cognition and Behavior, Radboud University, PO Box 9101, 6500 HB, Nijmegen, The Netherlands, l.k.janssen@donders.ru.nl.
authors.forename: Lieneke Katharina
authors.initials: LK
authors.lastname: Janssen
authors.forename: Guillaume
authors.initials: G
authors.lastname: Sescousse
authors.forename: Mahur Melina
authors.initials: MM
authors.lastname: Hashemi
authors.forename: Monique Harmina Maria
authors.initials: MH
authors.lastname: Timmer
authors.forename: Niels Peter
authors.initials: NP
authors.lastname: ter Huurne
authors.forename: Dirk Everdina Maria
authors.initials: DE
authors.lastname: Geurts
authors.forename: Roshan
authors.initials: R
authors.lastname: Cools
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D018592:Cross-Over Studies; D004298:Dopamine / Q000378:metabolism; D018492:Dopamine Antagonists / Q000494:pharmacology*; D004311:Double-Blind Method; D005715:Gambling / Q000378:metabolism* / Q000523:psychology; D006801:Humans; D008297:Male; D011678:Punishment / Q000523:psychology*; D017448:Receptors, Dopamine D2 / Q000378:metabolism*; D012193:Reversal Learning / Q000187:drug effects* / Q000502:physiology; D012201:Reward; D013469:Sulpiride / Q000494:pharmacology*
chemical_list: D018492:Dopamine Antagonists; D017448:Receptors, Dopamine D2; D013469:Sulpiride; D004298:Dopamine