title: Neuropsychological profiles in individuals at clinical high risk for psychosis: relationship to psychosis and intelligence.
abstract: BACKGROUND
  Characterizing neuropsychological (NP) functioning of individuals at clinical high risk (CHR) for psychosis may be useful for prediction of psychosis and understanding functional outcome. The degree to which NP impairments are associated with general cognitive ability and/or later emergence of full psychosis in CHR samples requires study with well-matched controls.
  
  
  METHODS
  We assessed NP functioning across eight cognitive domains in a sample of 73 CHR youth, 13 of whom developed psychotic-level symptoms after baseline assessment, and 34 healthy comparison (HC) subjects. Groups were matched on age, sex, ethnicity, handedness, subject and parent grade attainment, and median family income, and were comparable on WRAT-3 Reading, an estimate of premorbid IQ. Profile analysis was used to examine group differences and the role of IQ in profile shape.
  
  
  RESULTS
  The CHR sample demonstrated a significant difference in overall magnitude of NP impairment but only a small and nearly significant difference in profile shape, primarily due to a large impairment in olfactory identification. Individuals who subsequently developed psychotic-level symptoms demonstrated large impairments in verbal IQ, verbal memory and olfactory identification comparable in magnitude to first episode samples.
  
  
  CONCLUSIONS
  CHR status may be associated with moderate generalized cognitive impairments marked by some degree of selective impairment in olfaction and verbal memory. Impairments were greatest in those who later developed psychotic symptoms. Future study of olfaction in CHR samples may enhance early detection and specification of neurodevelopmental mechanisms of risk.
authors.affiliation: Center for Psychiatric Research, Maine Medical Center, 295 Park Avenue, Portland, ME 04102, USA. kwoodber@bidmc.harvard.edu
authors.forename: Kristen A
authors.initials: KA
authors.lastname: Woodberry
authors.forename: Larry J
authors.initials: LJ
authors.lastname: Seidman
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Giuliano
authors.forename: Mary B
authors.initials: MB
authors.lastname: Verdi
authors.forename: William L
authors.initials: WL
authors.lastname: Cook
authors.forename: William R
authors.initials: WR
authors.lastname: McFarlane
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003071:Cognition; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D007360:Intelligence; D007361:Intelligence Tests; D008297:Male; D008568:Memory; D009483:Neuropsychological Tests; D055696:Olfactory Perception; D011618:Psychotic Disorders / Q000175:diagnosis* / Q000523:psychology; D018570:Risk Assessment; D012684:Sensory Thresholds; D014706:Verbal Learning; D055815:Young Adult