title: Mismatch negativity: Alterations in adults from the general population who report subclinical psychotic symptoms.
abstract: BACKGROUND
  Deficits of mismatch negativity (MMN) in schizophrenia and individuals at risk for psychosis have been replicated many times. Several studies have also demonstrated the occurrence of subclinical psychotic symptoms within the general population. However, none has yet investigated MMN in individuals from the general population who report subclinical psychotic symptoms.
  
  
  METHODS
  The MMN to duration-, frequency-, and intensity deviants was recorded in 217 nonclinical individuals classified into a control group (n=72) and three subclinical groups: paranoid (n=44), psychotic (n=51), and mixed paranoid-psychotic (n=50). Amplitudes of MMN at frontocentral electrodes were referenced to average. Based on a three-source model of MMN generation, we conducted an MMN source analysis and compared the amplitudes of surface electrodes and sources among groups.
  
  
  RESULTS
  We found no significant differences in MMN amplitudes of surface electrodes. However, significant differences in MMN generation among the four groups were revealed at the frontal source for duration-deviant stimuli (P=0.01). We also detected a trend-level difference (P=0.05) in MMN activity among those groups for frequency deviants at the frontal source.
  
  
  CONCLUSIONS
  Individuals from the general population who report psychotic symptoms are a heterogeneous group. However, alterations exist in their frontal MMN activity. This increased activity might be an indicator of more sensitive perception regarding changes in the environment for individuals with subclinical psychotic symptoms.
authors.affiliation: The Zurich Program for Sustainable Development of Mental Health Services (ZInEP), Psychiatric Hospital, University of Zurich, Zurich, Switzerland; Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland.
authors.forename: C
authors.initials: C
authors.lastname: Döring
authors.affiliation: The Zurich Program for Sustainable Development of Mental Health Services (ZInEP), Psychiatric Hospital, University of Zurich, Zurich, Switzerland; Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland.
authors.forename: M
authors.initials: M
authors.lastname: Müller
authors.affiliation: The Zurich Program for Sustainable Development of Mental Health Services (ZInEP), Psychiatric Hospital, University of Zurich, Zurich, Switzerland; Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland.
authors.forename: F
authors.initials: F
authors.lastname: Hagenmuller
authors.affiliation: The Zurich Program for Sustainable Development of Mental Health Services (ZInEP), Psychiatric Hospital, University of Zurich, Zurich, Switzerland; Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland.
authors.forename: V
authors.initials: V
authors.lastname: Ajdacic-Gross
authors.affiliation: The Zurich Program for Sustainable Development of Mental Health Services (ZInEP), Psychiatric Hospital, University of Zurich, Zurich, Switzerland; Translational Neuromodeling Unit, Institute for Biomedical Engineering, University of Zurich and ETH Zurich, Zurich, Switzerland.
authors.forename: H
authors.initials: H
authors.lastname: Haker
authors.affiliation: The Zurich Program for Sustainable Development of Mental Health Services (ZInEP), Psychiatric Hospital, University of Zurich, Zurich, Switzerland; Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland.
authors.forename: W
authors.initials: W
authors.lastname: Kawohl
authors.affiliation: The Zurich Program for Sustainable Development of Mental Health Services (ZInEP), Psychiatric Hospital, University of Zurich, Zurich, Switzerland; Institute of Psychiatry, Laboratory of Neuroscience (LIM 27), University of Sao Paulo, Sao Paulo, Brazil.
authors.forename: W
authors.initials: W
authors.lastname: Rössler
authors.affiliation: The Zurich Program for Sustainable Development of Mental Health Services (ZInEP), Psychiatric Hospital, University of Zurich, Zurich, Switzerland; Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland. Electronic address: karsten.heekeren@uzh.ch.
authors.forename: K
authors.initials: K
authors.lastname: Heekeren
mesh_terms: D000328:Adult; D018450:Disease Progression; D006801:Humans; D008297:Male; D009341:Negativism; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000503:physiopathology* / Q000523:psychology*; D012559:Schizophrenia / Q000175:diagnosis
keywords: Biomarker; EEG; General population; Mismatch negativity; Psychosis; Source analysis