title: Brain activation to facial expressions in youth with PTSD symptoms.
abstract: OBJECTIVE
  This study examined activation to facial expressions in youth with a history of interpersonal trauma and current posttraumatic stress symptoms (PTSS) compared to healthy controls (HC).
  
  
  METHODS
  Twenty-three medication-naive youth with PTSS and 23 age- and gender-matched HC underwent functional magnetic resonance imaging (fMRI) while viewing fearful, angry, sad, happy, and neutral faces. Data were analyzed for group differences in location of activation, as well as timing of activation during the early versus late phase of the block. Using SPM5, significant activation (P < .05 FWE [Family-Wise Error] corrected, extent = 10 voxels) associated with the main effect of group was identified. Activation from selected clusters was extracted to SPSS software for further analysis of specific facial expressions and temporal patterns of activation.
  
  
  RESULTS
  The PTSS group showed significantly greater activation than controls in several regions, including the amygdala/hippocampus, medial prefrontal cortex, insula, and ventrolateral prefrontal cortex, and less activation than controls in the dorsolateral prefrontal cortex (DLPFC). These group differences in activation were greatest during angry, happy, and neutral faces, and predominantly during the early phase of the block. Post hoc analyses showed significant Group × Phase interactions in the right amygdala and left hippocampus.
  
  
  CONCLUSIONS
  Traumatic stress may impact development of brain regions important for emotion processing. Timing of activation may be altered in youth with PTSS.
authors.affiliation: Center for Interdisciplinary Brain Sciences Research (CIBSR), Stanford University School of Medicine, Stanford, CA, USA. agarrett@stanford.edu
authors.forename: Amy S
authors.initials: AS
authors.lastname: Garrett
authors.forename: Victor
authors.initials: V
authors.lastname: Carrion
authors.forename: Hilit
authors.initials: H
authors.lastname: Kletter
authors.forename: Asya
authors.initials: A
authors.lastname: Karchemskiy
authors.forename: Carl F
authors.initials: CF
authors.lastname: Weems
authors.forename: Allan
authors.initials: A
authors.lastname: Reiss
mesh_terms: D000293:Adolescent; D041923:Adolescent Development / Q000502:physiology*; D001921:Brain / Q000503:physiopathology*; D002648:Child; D004644:Emotions / Q000502:physiology*; D005149:Facial Expression; D005260:Female; D006801:Humans; D008016:Life Change Events; D008279:Magnetic Resonance Imaging; D008297:Male; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D012720:Severity of Illness Index; D013313:Stress Disorders, Post-Traumatic / Q000503:physiopathology*