title: Robust changes in reward circuitry during reward loss in current and former cocaine users during performance of a monetary incentive delay task.
abstract: BACKGROUND
  Abnormal function in reward circuitry in cocaine addiction could predate drug use as a risk factor, follow drug use as a consequence of substance-induced alterations, or both.
  
  
  METHODS
  We used a functional magnetic resonance imaging monetary incentive delay task (MIDT) to investigate reward-loss neural response differences among 42 current cocaine users, 35 former cocaine users, and 47 healthy subjects who also completed psychological measures and tasks related to impulsivity and reward.
  
  
  RESULTS
  We found various reward processing-related group differences in several MIDT phases. Across task phases we found a control > current user > former user activation pattern, except for loss outcome, where former compared with current cocaine users activated ventral tegmental area more robustly. We also found regional prefrontal activation differences during loss anticipation between cocaine-using groups. Both groups of cocaine users scored higher than control subjects on impulsivity, compulsivity and reward-punishment sensitivity factors. In addition, impulsivity-related factors correlated positively with activation in amygdala and negatively with anterior cingulate activation during loss anticipation.
  
  
  CONCLUSIONS
  Compared with healthy subjects, both former and current users displayed abnormal brain activation patterns during MIDT performance. Both cocaine groups differed similarly from healthy subjects, but differences between former and current users were localized to the ventral tegmental area during loss outcome and to prefrontal regions during loss anticipation, suggesting that long-term cocaine abstinence does not normalize most reward circuit abnormalities. Elevated impulsivity-related factors that relate to loss processing in current and former users suggest that these tendencies and relationships may pre-exist cocaine addiction.
authors.affiliation: Olin Neuropsychiatry Research Center, Institute of Living at Hartford Hospital, Hartford, Connecticut. Electronic address: Kpancholi@harthosp.org.
authors.forename: Krishna T
authors.initials: KT
authors.lastname: Patel
authors.forename: Michael C
authors.initials: MC
authors.lastname: Stevens
authors.forename: Shashwath A
authors.initials: SA
authors.lastname: Meda
authors.forename: Christine
authors.initials: C
authors.lastname: Muska
authors.forename: Andre D
authors.initials: AD
authors.lastname: Thomas
authors.forename: Marc N
authors.initials: MN
authors.lastname: Potenza
authors.forename: Godfrey D
authors.initials: GD
authors.lastname: Pearlson
mesh_terms: D000328:Adult; D059031:Anticipation, Psychological / Q000502:physiology*; D001921:Brain / Q000503:physiopathology*; D001931:Brain Mapping; D019970:Cocaine-Related Disorders / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007175:Impulsive Behavior / Q000503:physiopathology; D008279:Magnetic Resonance Imaging; D008297:Male; D012201:Reward
keywords: Addiction; cocaine; impulsivity; monetary incentive delay task; monetary loss; monetary reward