title: Executive dysfunction in first-episode schizophrenia and relationship to duration of untreated psychosis: the West London Study.
abstract: BACKGROUND
  Many studies have demonstrated early generalised cognitive impairment in schizophrenia.
  
  
  OBJECTIVE
  To examine executive function in first-episode schizophrenia, characterise the nature of the impairment and specify any relationships with symptoms and duration of untreated psychosis (DUP).
  
  
  METHODS
  Patients (n = 136) and normal controls (n = 81) were assessed with the Cambridge Automated Neuropsychological Test Battery, National Adult Reading Test IQ, and Scales for the Assessment of Positive and Negative Symptoms.
  
  
  RESULTS
  Memory and executive impairments in patients were independent of IQ level. Spatial working memory was impaired because of inadequate strategy use. On a planning task, patients showed reduced planning times and suboptimal problem-solving. On an attentional set-shifting task, 75% of patients were able to perform an extra-dimensional shift thought to be a core attribute of prefrontal cortex function. Those who failed had significantly longer DUP.
  
  
  CONCLUSIONS
  Prefrontal cortex function deteriorates at the onset of psychosis and continues to worsen over time.
authors.affiliation: Imperial College Faculty of Medicine, Charing Cross Site, St Dunstan's Road, London W6 8RP. e.joyce@ic.ac.uk
authors.forename: Eileen
authors.initials: E
authors.lastname: Joyce
authors.forename: Sam
authors.initials: S
authors.lastname: Hutton
authors.forename: Stan
authors.initials: S
authors.lastname: Mutsatsa
authors.forename: Heidi
authors.initials: H
authors.lastname: Gibbins
authors.forename: Emma
authors.initials: E
authors.lastname: Webb
authors.forename: Sonja
authors.initials: S
authors.lastname: Paul
authors.forename: Trevor
authors.initials: T
authors.lastname: Robbins
authors.forename: Thomas
authors.initials: T
authors.lastname: Barnes
mesh_terms: D000293:Adolescent; D000328:Adult; D001288:Attention; D003072:Cognition Disorders / Q000150:complications* / Q000523:psychology; D005260:Female; D006801:Humans; D007360:Intelligence; D008297:Male; D008568:Memory; D008606:Mental Processes; D008875:Middle Aged; D011340:Problem Solving; D012559:Schizophrenia / Q000150:complications*; D012565:Schizophrenic Psychology; D012737:Sex Factors; D013997:Time Factors