title: Dissociated effects of anticipating smoking versus monetary reward in the caudate as a function of smoking abstinence.
abstract: BACKGROUND
  Theories of addiction suggest that chronic smoking may be associated with both hypersensitivity to smoking and related cues and hyposensitivity to alternative reinforcers. However, neural responses to smoking and nonsmoking rewards are rarely evaluated within the same paradigm, leaving the extent to which both processes operate simultaneously uncertain. Behavioral evidence and theoretical models suggest that dysregulated reward processing may be more pronounced during deprivation from nicotine, but neuroimaging evidence on the effects of deprivation on reward processing is limited. The current study examined the impact of deprivation from smoking on neural processing of both smoking and monetary rewards.
  
  
  METHODS
  Two separate functional magnetic resonance imaging scans were performed in 38 daily smokers, one after smoking without restriction and one following 24 hours of abstinence. A rewarded guessing task was conducted during each scan to evaluate striatal blood oxygen level-dependent response during anticipation of both smoking and monetary rewards.
  
  
  RESULTS
  A significant reward type by abstinence interaction was observed in the bilateral caudate and medial prefrontal cortex during reward anticipation. The blood oxygen level-dependent response to anticipation of smoking reward was significantly higher and anticipation of monetary rewards was significantly lower during abstinence compared with nonabstinence. Attenuation of monetary reward-related activation during abstinence was significantly correlated with abstinence-induced increases in craving and withdrawal.
  
  
  CONCLUSIONS
  These results provide the first direct evidence of dissociated effects of smoking versus monetary rewards as a function of abstinence. The findings suggest an important neural pathway that may underlie the choice to smoke in lieu of alternative reinforcement during a quit attempt.
authors.affiliation: Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, North Carolina. Electronic address: maggie.sweitzer@duke.edu.
authors.forename: Maggie M
authors.initials: MM
authors.lastname: Sweitzer
authors.affiliation: Department of Human Development and Family Studies, The Pennsylvania State University, University Park, Pittsburgh, Pennsylvania.
authors.forename: Charles F
authors.initials: CF
authors.lastname: Geier
authors.affiliation: Department of Psychology, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Danielle L
authors.initials: DL
authors.lastname: Joel
authors.affiliation: Department of Psychology, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Patrick
authors.initials: P
authors.lastname: McGurrin
authors.affiliation: Department of Psychology, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Rachel L
authors.initials: RL
authors.lastname: Denlinger
authors.affiliation: Department of Psychology, University of Pittsburgh, Pittsburgh, Pennsylvania; Department of Psychiatry, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania; Center for Neural Basis of Cognition, University of Pittsburgh and Carnegie Mellon University, Pittsburgh, Pennsylvania.
authors.forename: Erika E
authors.initials: EE
authors.lastname: Forbes
authors.affiliation: Department of Psychology, University of Pittsburgh, Pittsburgh, Pennsylvania; Department of Psychiatry, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania; Center for Neural Basis of Cognition, University of Pittsburgh and Carnegie Mellon University, Pittsburgh, Pennsylvania.
authors.forename: Eric C
authors.initials: EC
authors.lastname: Donny
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002421:Caudate Nucleus / Q000098:blood supply / Q000503:physiopathology*; D003463:Cues; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009042:Motivation; D010100:Oxygen / Q000097:blood; D017397:Prefrontal Cortex / Q000098:blood supply / Q000503:physiopathology; D057566:Self Report; D013223:Statistics as Topic; D014029:Tobacco Use Disorder / Q000473:pathology* / Q000503:physiopathology* / Q000523:psychology*; D014040:Token Economy; D055815:Young Adult
chemical_list: D010100:Oxygen
keywords: fMRI; nicotine; reward; smoking; striatum; withdrawal