title: Abnormal gyral complexity in first-episode schizophrenia.
abstract: BACKGROUND
  Abnormalities in the patterns and frequency of cortical folding might help identify temporal and regionally specific disturbances in normal neurodevelopmental processes that occur in association with schizophrenia. Few studies, however, have investigated gyral complexity in schizophrenia.
  
  
  METHODS
  High-resolution magnetic resonance images were used to examine differences in gyral complexity, measured three-dimensionally in five separate hemispheric regions covering the entire cortical surface, in patients with first-episode schizophrenia (n = 50) compared with demographically matched healthy comparison subjects (n = 50). The modulating effects of gender and hemisphere were also examined.
  
  
  RESULTS
  Significant increases in cortical folding were observed in the right superior frontal cortex in male schizophrenic patients compared with male control subjects, but not between female diagnostic groups. Significant main effects of hemisphere were found in frontal, parietal, and occipital regions in directions complementary to cerebral torques.
  
  
  CONCLUSIONS
  Results support previous findings of right frontal hypergyria in male schizophrenic patients and suggest that these abnormalities predate illness onset and are of neurodevelopmental origin. Therefore, in schizophrenia, sexually dimorphic developmental processes and differences in hemispheric connectivity, which have been shown to influence the organization and/or frequency of cortical folding, seem to be disturbed during gyral formation in utero.
authors.affiliation: Laboratory of Neuro-Imaging, Geffen School of Medicine at University of California-Los Angeles, Los Angeles, CA 90095-1769, USA.
authors.forename: Katherine L
authors.initials: KL
authors.lastname: Narr
authors.forename: Robert M
authors.initials: RM
authors.lastname: Bilder
authors.forename: Sharon
authors.initials: S
authors.lastname: Kim
authors.forename: Paul M
authors.initials: PM
authors.lastname: Thompson
authors.forename: Philip
authors.initials: P
authors.lastname: Szeszko
authors.forename: Delbert
authors.initials: D
authors.lastname: Robinson
authors.forename: Eileen
authors.initials: E
authors.lastname: Luders
authors.forename: Arthur W
authors.initials: AW
authors.lastname: Toga
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001931:Brain Mapping; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000473:pathology*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000473:pathology*; D012737:Sex Factors