title: Amygdala response in patients with acute PTSD to masked and unmasked emotional facial expressions.
abstract: OBJECTIVE
  This study used functional magnetic resonance imaging to investigate amygdala response in patients with acute posttraumatic stress disorder (PTSD) to emotional expressions.
  
  
  METHODS
  Thirteen medication-free individuals with acute PTSD and no axis I psychiatric comorbidity were scanned while viewing pictures of fearful or happy faces, presented above or below consciousness, with backward masking.
  
  
  RESULTS
  There was a significant positive correlation between the severity of PTSD and the difference in amygdala responses between masked fearful and happy faces and a corresponding negative correlation for the difference between unmasked fearful and happy faces.
  
  
  CONCLUSIONS
  These findings suggest that functional abnormalities in brain responses to emotional stimuli observed in chronic PTSD are already apparent in its acute phase.
authors.affiliation: Douglas Hospital Research Centre, McGill University, 6875 LaSalle Blvd., F.B.C. Pavilion, Verdun, Quebec H4H 1R3, Canada. jorge.armony@mcgill.ca
authors.forename: Jorge L
authors.initials: JL
authors.lastname: Armony
authors.forename: Vincent
authors.initials: V
authors.lastname: Corbo
authors.forename: Marie-Hélène
authors.initials: MH
authors.lastname: Clément
authors.forename: Alain
authors.initials: A
authors.lastname: Brunet
mesh_terms: D000208:Acute Disease; D000328:Adult; D000679:Amygdala / Q000503:physiopathology*; D001931:Brain Mapping; D004644:Emotions / Q000502:physiology*; D005149:Facial Expression; D005239:Fear / Q000502:physiology / Q000523:psychology; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006240:Happiness; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D010470:Perceptual Masking / Q000502:physiology*; D012720:Severity of Illness Index; D012938:Social Perception; D013313:Stress Disorders, Post-Traumatic / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology