title: Corticolimbic blood flow during nontraumatic emotional processing in posttraumatic stress disorder.
abstract: BACKGROUND
  Recent brain imaging studies implicate dysfunction of limbic and paralimbic circuitry, including the amygdala and medial prefrontal cortex (MPFC), in the pathogenesis of posttraumatic stress disorder (PTSD) during traumatic recollection and imagery. However, the relationship between activity in these regions and general emotional processing unrelated to traumatic experience has not been fully examined.
  
  
  OBJECTIVE
  To investigate activity in the limbic and paralimbic brain regions in PTSD in response to a challenge with emotionally salient generic visual images.
  
  
  METHODS
  Cross-sectional, case-control study.
  
  
  METHODS
  Academic medical center.
  
  
  METHODS
  Sixteen Vietnam veterans with combat-related PTSD (PTSD group), 15 combat-exposed Vietnam veterans without PTSD (combat control group), and 15 age- and sex-matched healthy controls (normal control group).
  
  
  METHODS
  We used positron emission tomography to study regional cerebral blood flow while participants viewed complex visual pictures with negatively valenced/aversive, nonaversive ("neutral"), and blank pictures. Psychophysiologic and emotional self-report data were also recorded.
  
  
  RESULTS
  All 3 groups activated the dorsal MPFC to general salient content. Controls without PTSD activated the left amygdala in response to aversive stimuli. Normal controls activated the ventral MPFC and combat-exposed non-PTSD and PTSD participants exhibited either no response or deactivation in these regions, respectively, during negative emotional experience.
  
  
  CONCLUSIONS
  Consistent with current functional neuroanatomic models, patients with PTSD exhibited altered neural responses in the amygdala and ventral MPFC during the processing of emotionally salient but trauma-unrelated stimuli, potentially reflecting disorder-specific changes. Activation of the amygdala and lack of ventral MPFC deactivation to negatively valenced images in combat controls may reflect compensatory changes after trauma exposure that are not associated with PTSD.
authors.affiliation: Department of Psychiatry, Pritzker School of Medicine, The University of Chicago, Chicago, Ill, USA.
authors.forename: K Luan
authors.initials: KL
authors.lastname: Phan
authors.forename: Jennifer C
authors.initials: JC
authors.lastname: Britton
authors.forename: Stephan F
authors.initials: SF
authors.lastname: Taylor
authors.forename: Lorraine M
authors.initials: LM
authors.lastname: Fig
authors.forename: Israel
authors.initials: I
authors.lastname: Liberzon
mesh_terms: D000328:Adult; D000679:Amygdala / Q000098:blood supply / Q000000981:diagnostic imaging; D001143:Arousal / Q000502:physiology; D001931:Brain Mapping; D003130:Combat Disorders / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000503:physiopathology; D004644:Emotions / Q000502:physiology*; D005239:Fear / Q000502:physiology; D005712:Galvanic Skin Response / Q000502:physiology; D006801:Humans; D008016:Life Change Events; D008032:Limbic System / Q000098:blood supply* / Q000000981:diagnostic imaging; D008297:Male; D008568:Memory / Q000502:physiology; D008875:Middle Aged; D010775:Photic Stimulation; D049268:Positron-Emission Tomography; D017397:Prefrontal Cortex / Q000098:blood supply* / Q000000981:diagnostic imaging; D012039:Regional Blood Flow / Q000502:physiology; D013313:Stress Disorders, Post-Traumatic / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology; D014796:Visual Perception / Q000502:physiology*