title: The influence of monetary punishment on cognitive control in abstinent cocaine-users.
abstract: BACKGROUND
  Dependent drug users show a diminished neural response to punishment, in both limbic and cortical regions, though it remains unclear how such changes influence cognitive processes critical to addiction. To assess this relationship, we examined the influence of monetary punishment on inhibitory control and adaptive post-error behavior in abstinent cocaine dependent (CD) participants.
  
  
  METHODS
  15 abstinent CD and 15 matched control participants performed a Go/No-go response inhibition task, which administered monetary fines for failed response inhibition, during collection of fMRI data.
  
  
  RESULTS
  CD participants showed reduced inhibitory control and significantly less adaptive post-error slowing in response to punishment, when compared to controls. The diminished behavioral punishment sensitivity shown by CD participants was associated with significant hypoactive error-related BOLD responses in the dorsal anterior cingulate cortex (ACC), right insula and right prefrontal regions. Specifically, CD participants' error-related response in these regions was not modulated by the presence of punishment, whereas control participants' response showed a significant BOLD increase during punished errors.
  
  
  CONCLUSIONS
  CD participants showed a blunted response to failed control (errors) that was not modulated by punishment. Consistent with previous findings of reduced sensitivity to monetary loss in cocaine users, we further demonstrate that such insensitivity is associated with an inability to increase cognitive control in the face of negative consequences, a core symptom of addiction. The pattern of deficits in the CD group may have implications for interventions that attempt to improve cognitive control in drug dependent groups via positive/negative incentives.
authors.affiliation: University of Melbourne, School of Psychological Sciences, Melbourne, Victoria, 3010, Australia. Electronic address: hesterr@unimelb.edu.au.
authors.forename: Robert
authors.initials: R
authors.lastname: Hester
authors.forename: Ryan P
authors.initials: RP
authors.lastname: Bell
authors.forename: John J
authors.initials: JJ
authors.lastname: Foxe
authors.forename: Hugh
authors.initials: H
authors.lastname: Garavan
mesh_terms: D000328:Adult; D001931:Brain Mapping; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000503:physiopathology*; D019970:Cocaine-Related Disorders / Q000503:physiopathology* / Q000523:psychology*; D003071:Cognition / Q000502:physiology*; D005260:Female; D006179:Gyrus Cinguli / Q000503:physiopathology*; D006801:Humans; D007266:Inhibition, Psychological; D008297:Male; D008875:Middle Aged; D017397:Prefrontal Cortex / Q000503:physiopathology*; D011597:Psychomotor Performance / Q000502:physiology; D011678:Punishment / Q000523:psychology*
keywords: Cocaine; Cognitive control; Drug dependence; Error-related; Performance monitoring