title: Altered white-matter architecture in treatment-naive adolescents with clinical depression.
abstract: BACKGROUND
  Depressive disorders are highly prevalent in adolescence and confer a heightened risk of recurrence in adulthood. Insight into the developmental neurocircuitry of depression could advance our understanding of depression and aid the development of effective treatment strategies. Whereas white-matter (WM) abnormalities are strongly implicated in adult depression, we still lack a firm understanding of WM architecture in adolescent depression. Using diffusion tensor imaging (DTI), we set out to investigate WM microstructure in a sample of clinically depressed adolescents relative to matched controls.
  
  
  METHODS
  We employed tract-based spatial statistics (TBSS) to examine WM microstructure in 25 treatment-naive adolescents with clinical depression relative to 21 matched controls. Using TBSS, we examined fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD) and mean diffusivity (MD). Threshold-free cluster enhancement (TFCE) with family-wise error (FWE) correction was used to control for multiple comparisons.
  
  
  RESULTS
  Our analysis revealed abnormal WM microstructure in clinically depressed adolescents. More specifically, whole-brain analysis revealed that patients had lower FA values in the body of the corpus callosum (CC), coupled with elevated RD and MD, and preserved AD. Conversely, region-of-interest analysis revealed that patients had higher FA values in the uncinate fasciculus (UF), coupled with elevated AD, reduced RD and preserved MD.
  
  
  CONCLUSIONS
  In line with neurocircuitry models of depression, our findings suggest that WM abnormalities within pathways facilitating cognitive and emotional functioning are involved in the pathophysiology of depression. Importantly, our findings show that these WM abnormalities are already present early in the course of the disorder.
authors: Department of Child and Adolescent Psychiatry, Curium,Leiden University Medical Center,The Netherlands.
authors: M
authors: M
authors: Aghajani
authors: Leiden Institute for Brain and Cognition (LIBC),The Netherlands.
authors: I M
authors: IM
authors: Veer
authors: Department of Child and Adolescent Psychiatry, Curium,Leiden University Medical Center,The Netherlands.
authors: N D J
authors: ND
authors: van Lang
authors: Department of Child and Adolescent Psychiatry, Curium,Leiden University Medical Center,The Netherlands.
authors: P H F
authors: PH
authors: Meens
authors: Department of Child and Adolescent Psychiatry, Curium,Leiden University Medical Center,The Netherlands.
authors: B G
authors: BG
authors: van den Bulk
authors: Leiden Institute for Brain and Cognition (LIBC),The Netherlands.
authors: S A R B
authors: SA
authors: Rombouts
authors: Department of Child and Adolescent Psychiatry, Curium,Leiden University Medical Center,The Netherlands.
authors: R R J M
authors: RR
authors: Vermeiren
authors: Leiden Institute for Brain and Cognition (LIBC),The Netherlands.
authors: N J
authors: NJ
authors: van der Wee
mesh_terms: D000293:Adolescent; D003866:Depressive Disorder / Q000473:pathology*; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D008297:Male; D009434:Neural Pathways / Q000473:pathology; D066127:White Matter / Q000473:pathology*