title: Olfactory processing in schizophrenia, non-ill first-degree family members, and young people at-risk for psychosis.
abstract: OBJECTIVE
  While deficits in odor identification and discrimination have been reported in schizophrenia, few studies have examined the relative specificity of these deficits in patients and at-risk youth.
  
  
  METHODS
  Sniffin' Sticks odor identification and discrimination were assessed in schizophrenia outpatients and non-ill first-degree relatives (Study One), as well as youth at clinical (CR) or genetic (GR) risk for schizophrenia (Study Two). Scores were z-transformed, using the performance of a demographically-matched adult or adolescent comparison group.
  
  
  RESULTS
  Patients and relatives were impaired on odor identification, but odor discrimination impairment was limited to the patient group. A similar pattern of impairment emerged in at-risk youth. GR youth were impaired on odor identification but not discrimination, while CR youth were impaired on both tasks. In patients, olfactory impairment was correlated with negative symptomatology.
  
  
  CONCLUSIONS
  To our knowledge, this is the first study to show that CR youth are impaired on both olfactory tasks, as observed in adult schizophrenia patients. GR youth were impaired only on odor identification like their adult counterparts. These data suggest that odor identification impairment, in isolation, may represent a genetic marker of vulnerability for schizophrenia, while odor discrimination deficits may be a biomarker associated with the development of psychosis.
authors: Neuropsychiatry Section, Department of Psychiatry.
authors: Vidyulata
authors: V
authors: Kamath
authors: Bruce I
authors: BI
authors: Turetsky
authors: Monica E
authors: ME
authors: Calkins
authors: Christian G
authors: CG
authors: Kohler
authors: Catherine G
authors: CG
authors: Conroy
authors: Karin
authors: K
authors: Borgmann-Winter
authors: Dana E
authors: DE
authors: Gatto
authors: Raquel E
authors: RE
authors: Gur
authors: Paul J
authors: PJ
authors: Moberg
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D004192:Discrimination, Psychological; D005190:Family; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009812:Odorants; D000857:Olfaction Disorders / Q000150:complications / Q000235:genetics / Q000503:physiopathology*; D062706:Prodromal Symptoms; D012306:Risk; D012559:Schizophrenia / Q000150:complications / Q000235:genetics / Q000503:physiopathology*; D012903:Smell; D055815:Young Adult