title: Relationship between neurocognition and regional brain volumes in traumatized adolescents with and without posttraumatic stress disorder.
abstract: OBJECTIVE
  Studies using convergent neurocognitive and structural imaging paradigms in adolescent posttraumatic stress disorder (PTSD) are limited; in the current study we used both voxel-based morphometry (VBM) to obtain between-group volumetric differences, and Freesurfer to examine the relationship between cognition and regional brain volumes.
  
  
  METHODS
  Participants were 21 traumatized adolescents with PTSD matched with 32 traumatized adolescents without PTSD. Magnetic resonance images were obtained on a 1.5-Tesla MAGNETOM Siemens Symphony scanner. VBM implemented on FSL was then used to compare between-group grey matter volumes, after which Freesurfer was used to obtain global volume and thickness measurements in different brain regions.
  
  
  RESULTS
  Significant between-group neurocognitive differences were found for tests of attention, delayed recall and visual reconstruction. On VBM, reduced grey matter was found in three regions in the PTSD group: left insula, right precuneus and right cingulate gyrus, using uncorrected values (p < 0.001), while no statistically significant between-group differences were found on the initial Freesurfer stream. Further Freesurfer analysis on Qdec revealed significant reductions in the insula for the PTSD group. In addition, volumetric changes in the corpus callosum and insula were significantly associated with deficits in logical memory and visual reproduction on Freesurfer analysis.
  
  
  CONCLUSIONS
  Trauma exposure of itself may be sufficient to cause structural changes in adolescents regardless of PTSD development.
authors.affiliation: South African Research Chairs Initiative in Posttraumatic Stress Disorder, Stellenbosch University, Cape Town, South Africa.
authors.forename: Fatima
authors.initials: F
authors.lastname: Ahmed
authors.forename: Bruce S
authors.initials: BS
authors.lastname: Spottiswoode
authors.forename: Paul D
authors.initials: PD
authors.lastname: Carey
authors.forename: Dan J
authors.initials: DJ
authors.lastname: Stein
authors.forename: Soraya
authors.initials: S
authors.lastname: Seedat
mesh_terms: D000293:Adolescent; D001921:Brain / Q000473:pathology*; D001931:Brain Mapping; D016022:Case-Control Studies; D002648:Child; D003072:Cognition Disorders / Q000209:etiology*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D013313:Stress Disorders, Post-Traumatic / Q000150:complications* / Q000473:pathology*