title: Correlations between brain structure and symptom dimensions of psychosis in schizophrenia, schizoaffective, and psychotic bipolar I disorders.
abstract: BACKGROUND
  Structural alterations may correlate with symptom severity in psychotic disorders, but the existing literature on this issue is heterogeneous. In addition, it is not known how cortical thickness and cortical surface area correlate with symptom dimensions of psychosis.
  
  
  METHODS
  Subjects included 455 individuals with schizophrenia, schizoaffective, or bipolar I disorders. Data were obtained as part of the Bipolar Schizophrenia Network for Intermediate Phenotypes study. Diagnosis was made through the Structured Clinical Interview for DSM-IV. Positive and negative symptom subscales were assessed using the Positive and Negative Syndrome Scale. Structural brain measurements were extracted from T1-weight structural MRIs using FreeSurfer v5.1 and were correlated with symptom subscales using partial correlations. Exploratory factor analysis was also used to identify factors among those regions correlating with symptom subscales.
  
  
  RESULTS
  The positive symptom subscale correlated inversely with gray matter volume (GMV) and cortical thickness in frontal and temporal regions, whereas the negative symptom subscale correlated inversely with right frontal cortical surface area. Among regions correlating with the positive subscale, factor analysis identified four factors, including a temporal cortical thickness factor and frontal GMV factor. Among regions correlating with the negative subscale, factor analysis identified a frontal GMV-cortical surface area factor. There was no significant diagnosis by structure interactions with symptom severity.
  
  
  CONCLUSIONS
  Structural measures correlate with positive and negative symptom severity in psychotic disorders. Cortical thickness demonstrated more associations with psychopathology than cortical surface area.
authors.affiliation: Department of Psychiatry, Beth Israel Deaconess Medical Center , Boston, MA; Division of Public Psychiatry, Massachusetts Mental Health Center , Boston, MA;
authors.forename: Jaya L
authors.initials: JL
authors.lastname: Padmanabhan
authors.affiliation: Department of Psychiatry, Beth Israel Deaconess Medical Center , Boston, MA; Division of Public Psychiatry, Massachusetts Mental Health Center , Boston, MA;
authors.forename: Neeraj
authors.initials: N
authors.lastname: Tandon
authors.forename: Chiara S
authors.initials: CS
authors.lastname: Haller
authors.affiliation: Department of Psychiatry, Beth Israel Deaconess Medical Center , Boston, MA; Division of Public Psychiatry, Massachusetts Mental Health Center , Boston, MA;
authors.forename: Ian T
authors.initials: IT
authors.lastname: Mathew
authors.affiliation: School of Social Work, Psychiatry, and Clinical and Translational Sciences Institute, University of Pittsburgh, Pittsburgh, PA; Western Psychiatric Institute and Clinic, Pittsburgh, PA;
authors.forename: Shaun M
authors.initials: SM
authors.lastname: Eack
authors.affiliation: Departments of Psychiatry and Neuroscience, Bio-Imaging Research Center, University of Georgia, Athens, GA;
authors.forename: Brett A
authors.initials: BA
authors.lastname: Clementz
authors.affiliation: Departments of Psychiatry and Neurobiology, Yale University, New Haven, CT; Olin Neuropsychiatry Research Center, Hartford Hospital/Institute of Living, Hartford, CT;
authors.forename: Godfrey D
authors.initials: GD
authors.lastname: Pearlson
authors.affiliation: Department of Psychiatry, University of Illinois at Chicago, Chicago, IL; Department of Psychiatry, University of Texas Southwestern Medical School, Dallas, TX.
authors.forename: John A
authors.initials: JA
authors.lastname: Sweeney
authors.affiliation: Department of Psychiatry, University of Texas Southwestern Medical School, Dallas, TX.
authors.forename: Carol A
authors.initials: CA
authors.lastname: Tamminga
authors.affiliation: Department of Psychiatry, Beth Israel Deaconess Medical Center , Boston, MA; Division of Public Psychiatry, Massachusetts Mental Health Center , Boston, MA; Department of Psychiatry, Harvard Medical School, Boston, MA; mkeshava@bidmc.harvard.edu.
authors.forename: Matcheri S
authors.initials: MS
authors.lastname: Keshavan
mesh_terms: D000328:Adult; D001714:Bipolar Disorder / Q000473:pathology* / Q000523:psychology; D001921:Brain / Q000473:pathology; D005163:Factor Analysis, Statistical; D005260:Female; D005625:Frontal Lobe / Q000473:pathology*; D066128:Gray Matter / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D011618:Psychotic Disorders / Q000473:pathology* / Q000523:psychology; D012559:Schizophrenia / Q000473:pathology*; D012565:Schizophrenic Psychology; D013702:Temporal Lobe / Q000473:pathology*; D055815:Young Adult
keywords: cortical thickness; gray matter; negative; positive; psychopathology; surface area