title: Incentive motivation in first-episode psychosis: a behavioural study.
abstract: BACKGROUND
  It has been proposed that there are abnormalities in incentive motivational processing in psychosis, possibly secondary to subcortical dopamine abnormalities, but few empirical studies have addressed this issue.
  
  
  METHODS
  We studied incentive motivation in 18 first-episode psychosis patients from the Cambridge early psychosis service CAMEO and 19 control participants using the Cued Reinforcement Reaction Time Task, which measures motivationally driven behaviour. We also gathered information on participants' attentional, executive and spatial working memory function in order to determine whether any incentive motivation deficits were secondary to generalised cognitive impairment.
  
  
  RESULTS
  We demonstrated the anticipated "reinforcement-related speeding" effect in controls (17 out of 19 control participants responded faster during an "odd-one-out" task in response to a cue that indicated a high likelihood of a large points reward). Only 4 out of 18 patients showed this effect and there was a significant interaction effect between reinforcement probability and diagnosis on reaction time (F1,35 = 14.2, p = 0.001). This deficit was present in spite of preserved executive and attentional function in patients, and persisted even in antipsychotic medication free patients.
  
  
  CONCLUSIONS
  There are incentive motivation processing abnormalities in first-episode psychosis; these may be secondary to dopamine dysfunction and are not attributable to generalised cognitive impairment.
authors.affiliation: Brain Mapping Unit, Department of Psychiatry, University of Cambridge, Cambridge, UK. gm285@cam.ac.uk
authors.forename: Graham K
authors.initials: GK
authors.lastname: Murray
authors.forename: Luke
authors.initials: L
authors.lastname: Clark
authors.forename: Philip R
authors.initials: PR
authors.lastname: Corlett
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Blackwell
authors.forename: Roshan
authors.initials: R
authors.lastname: Cools
authors.forename: Peter B
authors.initials: PB
authors.lastname: Jones
authors.forename: Trevor W
authors.initials: TW
authors.lastname: Robbins
authors.forename: Luise
authors.initials: L
authors.lastname: Poustka
mesh_terms: D000293:Adolescent; D000328:Adult; D014150:Antipsychotic Agents / Q000627:therapeutic use; D003463:Cues; D005260:Female; D006801:Humans; D007600:Judgment; D008297:Male; D009042:Motivation; D018579:Patient Selection; D011336:Probability; D011618:Psychotic Disorders / Q000188:drug therapy / Q000523:psychology*; D012016:Reference Values; D012054:Reinforcement, Psychology
chemical_list: D014150:Antipsychotic Agents