title: Dysfunctional reward circuitry in obsessive-compulsive disorder.
abstract: BACKGROUND
  Obsessive-compulsive disorder (OCD) is primarily conceived as an anxiety disorder but has features resembling addictive behavior. Patients with OCD may develop dependency upon compulsive behaviors because of the rewarding effects following reduction of obsession-induced anxiety. Reward processing is critically dependent on ventral striatal-orbitofrontal circuitry and brain imaging studies in OCD have consistently shown abnormal activation within this circuitry. This is the first functional imaging study to investigate explicitly reward circuitry in OCD.
  
  
  METHODS
  Brain activity during reward anticipation and receipt was compared between 18 OCD patients and 19 healthy control subjects, using a monetary incentive delay task and functional magnetic resonance imaging. Reward processing was compared between OCD patients with predominantly contamination fear and patients with predominantly high-risk assessment.
  
  
  RESULTS
  Obsessive-compulsive disorder patients showed attenuated reward anticipation activity in the nucleus accumbens compared with healthy control subjects. Reduced activity of the nucleus accumbens was more pronounced in OCD patients with contamination fear than in patients with high-risk assessment. Brain activity during reward receipt was similar between patients and control subjects. A hint toward more dysfunctional reward processing was found in treatment-resistant OCD patients who subsequently were successfully treated with deep brain stimulation of the nucleus accumbens.
  
  
  CONCLUSIONS
  Obsessive-compulsive disorder patients may be less able to make beneficial choices because of altered nucleus accumbens activation when anticipating rewards. This finding supports the conceptualization of OCD as a disorder of reward processing and behavioral addiction.
authors.affiliation: Department of Psychiatry, Academic Medical Center, Amsterdam, The Netherlands. m.figee@amc.nl
authors.forename: Martijn
authors.initials: M
authors.lastname: Figee
authors.forename: Matthijs
authors.initials: M
authors.lastname: Vink
authors.forename: Femke
authors.initials: F
authors.lastname: de Geus
authors.forename: Nienke
authors.initials: N
authors.lastname: Vulink
authors.forename: Dick J
authors.initials: DJ
authors.lastname: Veltman
authors.forename: Herman
authors.initials: H
authors.lastname: Westenberg
authors.forename: Damiaan
authors.initials: D
authors.lastname: Denys
mesh_terms: D000328:Adult; D001921:Brain / Q000503:physiopathology; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009415:Nerve Net / Q000503:physiopathology*; D009714:Nucleus Accumbens / Q000503:physiopathology*; D009771:Obsessive-Compulsive Disorder / Q000503:physiopathology*; D011930:Reaction Time / Q000502:physiology; D012201:Reward; D012720:Severity of Illness Index