title: Corpus callosal morphology in youth with bipolar depression.
abstract: OBJECTIVE
  Recent evidence has demonstrated that corpus callosum maturation follows a similar developmental timeline to cognitive processes. Bipolar disorder (BD) has been associated with disruptions in error processing, response inhibition, and motor functioning, which are mediated by underlying white matter structures, including the corpus callosum. Disruptions in white matter integrity have been demonstrated in BD. However, it is unknown whether alterations in the developmental trajectory of the corpus callosum may contribute to cognitive impairments in the disorder.
  
  
  METHODS
  We assessed the area of the corpus callosum and its subregions (the genu, rostral body, anterior and posterior bodies, isthmus, and splenium) in 14 treatment-naïve adolescents with BD (<21 years of age and in the depressed phase) and 18 healthy adolescent controls.
  
  
  RESULTS
  In comparison with healthy controls, participants with BD demonstrated a significantly reduced overall corpus callosum area. We also noted smaller areas in the anterior and posterior mid-body of the corpus callosum in adolescents with BD.
  
  
  CONCLUSIONS
  Our results suggest that commissural fibers of the corpus callosum are disrupted in early-onset BD. Specific decreases in the anterior and posterior mid-body callosal aspects may contribute to motor organization and inhibition deficits seen in BD. These findings are consistent with the involvement of inter-hemispheric tracts in early-onset BD, which may reflect an early deviation in white matter development.
authors.affiliation: Department of Psychiatry, University of Calgary, Calgary, AB, Canada; Department of Pediatrics, University of Calgary, Calgary, AB, Canada; Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada.
authors.forename: Frank P
authors.initials: FP
authors.lastname: MacMaster
authors.forename: Lisa Marie
authors.initials: LM
authors.lastname: Langevin
authors.forename: Natalia
authors.initials: N
authors.lastname: Jaworska
authors.forename: Anne
authors.initials: A
authors.lastname: Kemp
authors.forename: Mariko
authors.initials: M
authors.lastname: Sembo
mesh_terms: D000293:Adolescent; D000704:Analysis of Variance; D001714:Bipolar Disorder / Q000473:pathology*; D002648:Child; D003337:Corpus Callosum / Q000473:pathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D055815:Young Adult
keywords: adolescent; bipolar disorder; corpus callosum; depression