title: Exaggerated brain activation during emotion processing in unaffected siblings of patients with schizophrenia.
abstract: BACKGROUND
  Schizophrenia is characterized by impaired social cognition, including emotion processing. Behavioral studies have reported impaired performance on various emotion processing tasks, and imaging studies in patients have observed aberrant activity within the underlying neural circuitry. Also, subjects at increased genetic risk of developing schizophrenia, including unaffected siblings of patients, show behavioral impairments in emotion processing. It is unclear, however, whether and how the underlying neural system is disrupted in these subjects. In this study, we investigated whether siblings of patients with schizophrenia show abnormal brain activation during basic emotion processing.
  
  
  METHODS
  Brain activity was measured using functional magnetic resonance imaging in 24 unaffected siblings of patients with schizophrenia and 25 healthy control subjects while they viewed and rated neutral, positive, and negative pictures. None of the subjects had a psychiatric disorder, and the two groups did not differ in age, gender, or level of own, paternal, or maternal education.
  
  
  RESULTS
  Compared with control subjects, siblings showed increased activity within the amygdala, hippocampus, medial prefrontal cortex, posterior and anterior cingulate cortex, and middle temporal gyrus in response to emotionally arousing pictures relative to neutral pictures. No activation differences between the groups were found during the neutral stimuli, indicating that the observed hyperactivity is likely caused by abnormal emotion processing rather than impaired visuoattentional processing.
  
  
  CONCLUSIONS
  Our findings of hyperactivity in siblings during emotion processing suggest that functional abnormalities within the neural circuitry of emotion processing are related to the genetic risk for developing schizophrenia.
authors.affiliation: Rudolf Magnus Institute of Neuroscience, Department of Psychiatry, University Medical Center Utrecht, Utrecht, The Netherlands. m.vanbuuren-2@umcutrecht.nl
authors.forename: Mariët
authors.initials: M
authors.lastname: van Buuren
authors.forename: Matthijs
authors.initials: M
authors.lastname: Vink
authors.forename: Anca E
authors.initials: AE
authors.lastname: Rapcencu
authors.forename: René S
authors.initials: RS
authors.lastname: Kahn
mesh_terms: D000328:Adult; D001921:Brain / Q000503:physiopathology*; D001931:Brain Mapping / Q000379:methods; D004644:Emotions / Q000502:physiology*; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D010775:Photic Stimulation; D011597:Psychomotor Performance / Q000502:physiology*; D012559:Schizophrenia / Q000235:genetics / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D035781:Siblings / Q000523:psychology*