title: Evidence that hippocampal-parahippocampal dysfunction is related to genetic risk for schizophrenia.
abstract: BACKGROUND
  Abnormalities in hippocampal-parahippocampal (H-PH) function are prominent features of schizophrenia and have been associated with deficits in episodic memory. However, it remains unclear whether these abnormalities represent a phenotype related to genetic risk for schizophrenia or whether they are related to disease state.
  
  
  METHODS
  We investigated H-PH-mediated behavior and physiology, using blood oxygenation level-dependent functional magnetic resonance imaging (BOLD fMRI), during episodic memory in a sample of patients with schizophrenia, clinically unaffected siblings and healthy subjects.
  
  
  RESULTS
  Patients with schizophrenia and unaffected siblings displayed abnormalities in episodic memory performance. During an fMRI memory encoding task, both patients and siblings demonstrated a similar pattern of reduced H-PH engagement compared with healthy subjects.
  
  
  CONCLUSIONS
  Our findings suggest that the pathophysiological mechanism underlying the inability of patients with schizophrenia to properly engage the H-PH during episodic memory is related to genetic risk for the disorder. Therefore, H-PH dysfunction can be assumed as a schizophrenia susceptibility-related phenotype.
authors.affiliation: IRCCS 'Casa Sollievo della Sofferenza', San Giovanni Rotondo, Foggia, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Di Giorgio
authors.forename: B
authors.initials: B
authors.lastname: Gelao
authors.forename: G
authors.initials: G
authors.lastname: Caforio
authors.forename: R
authors.initials: R
authors.lastname: Romano
authors.forename: I
authors.initials: I
authors.lastname: Andriola
authors.forename: E
authors.initials: E
authors.lastname: D'Ambrosio
authors.forename: A
authors.initials: A
authors.lastname: Papazacharias
authors.forename: F
authors.initials: F
authors.lastname: Elifani
authors.forename: L Lo
authors.initials: LL
authors.lastname: Bianco
authors.forename: P
authors.initials: P
authors.lastname: Taurisano
authors.forename: L
authors.initials: L
authors.lastname: Fazio
authors.forename: T
authors.initials: T
authors.lastname: Popolizio
authors.forename: G
authors.initials: G
authors.lastname: Blasi
authors.forename: A
authors.initials: A
authors.lastname: Bertolino
mesh_terms: D000328:Adult; D001931:Brain Mapping; D005260:Female; D020022:Genetic Predisposition to Disease; D006624:Hippocampus / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D061212:Memory, Episodic; D008875:Middle Aged; D020534:Parahippocampal Gyrus / Q000502:physiology*; D010641:Phenotype; D012559:Schizophrenia / Q000235:genetics / Q000503:physiopathology*; D035781:Siblings