title: Dysregulation in cortical reactivity to emotional faces in PTSD patients with high dissociation symptoms.
abstract: BACKGROUND
  Predominant dissociation in posttraumatic stress disorder (PTSD) is characterized by restricted affective responses to positive stimuli. To date, no studies have examined neural responses to a range of emotional expressions in PTSD with high dissociative symptoms.
  
  
  OBJECTIVE
  This study tested the hypothesis that PTSD patients with high dissociative symptoms will display increased event-related potential (ERP) amplitudes in early components (N1, P1) to threatening faces (angry, fearful), and reduced later ERP amplitudes (Vertex Positive Potential (VPP), P3) to happy faces compared to PTSD patients with low dissociative symptoms.
  
  
  METHODS
  Thirty-nine civilians with PTSD were classified as high dissociative (n=16) or low dissociative (n=23) according to their responses on the Clinician Administered Dissociative States Scale. ERPs were recorded, whilst participants viewed emotional (happy, angry, fear) and neutral facial expressions in a passive viewing task.
  
  
  RESULTS
  High dissociative PTSD patients displayed significantly increased N120 amplitude to the majority of facial expressions (neutral, happy, and angry) compared to low dissociative PTSD patients under conscious and preconscious conditions. The high dissociative PTSD group had significantly reduced VPP amplitude to happy faces in the conscious condition.
  
  
  CONCLUSIONS
  High dissociative PTSD patients displayed increased early (preconscious) cortical responses to emotional stimuli, and specific reductions to happy facial expressions in later (conscious), face-specific components compared to low dissociative PTSD patients. Dissociation in PTSD may act to increase initial pre-attentive processing of affective stimuli, and specifically reduce cortical reactivity to happy faces when consciously processing these stimuli.
authors.affiliation: School of Psychology, University of New South Wales, Australia.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Klimova
authors.forename: Richard A
authors.initials: RA
authors.lastname: Bryant
authors.forename: Leanne M
authors.initials: LM
authors.lastname: Williams
authors.forename: Kim Louise
authors.initials: KL
authors.lastname: Felmingham
keywords: ERPs; dissociation; emotion; faces; posttraumatic stress disorder (PTSD)
references.citation: Psychol Med. 2008 Dec;38(12):1771-80
references.pmid: 18294420
references.citation: J Trauma Stress. 1998 Jan;11(1):125-36
references.pmid: 9479681
references.citation: J Neurosci Methods. 2002 Apr 15;115(2):137-43
references.pmid: 11992665
references.citation: Neuroreport. 2003 Apr 15;14(5):777-80
references.pmid: 12692482
references.citation: Clin Psychol Rev. 2005 Jan;25(1):1-23
references.pmid: 15596078
references.citation: Curr Opin Neurobiol. 1998 Apr;8(2):202-10
references.pmid: 9635203
references.citation: Biol Psychiatry. 2002 Aug 15;52(4):305-11
references.pmid: 12208637
references.citation: Neuroreport. 2000 Jul 14;11(10):2319-24
references.pmid: 10923693
references.citation: Int J Psychophysiol. 2007 Nov;66(2):141-53
references.pmid: 17544534
references.citation: Hum Brain Mapp. 2004 Feb;21(2):64-74
references.pmid: 14755594
references.citation: Brain Topogr. 2010 Mar;23(1):27-40
references.pmid: 20043199
references.citation: Biol Psychiatry. 1993 Sep 1;34(5):311-20
references.pmid: 8399831
references.citation: Br J Psychiatry. 2002 Apr;180:363-8
references.pmid: 11925361
references.citation: Neuroreport. 2002 Mar 25;13(4):427-31
references.pmid: 11930154
references.citation: Electroencephalogr Clin Neurophysiol. 1983 Apr;55(4):468-84
references.pmid: 6187540
references.citation: Biol Psychol. 1995 Oct;41(2):103-46
references.pmid: 8534788
references.citation: Ann N Y Acad Sci. 2006 Jul;1071:125-36
references.pmid: 16891567
references.citation: J Nerv Ment Dis. 2007 Jan;195(1):48-53
references.pmid: 17220739
references.citation: Neurosci Res. 2009 May;64(1):30-40
references.pmid: 19428681
references.citation: Biol Psychol. 2008 Mar;77(3):247-65
references.pmid: 18164800
references.citation: Psychiatry Res. 2010 Aug 15;178(3):501-6
references.pmid: 20537404
references.citation: Psychiatry Res. 2002 Mar 15;109(2):171-9
references.pmid: 11927142
references.citation: J Neurophysiol. 1994 Feb;71(2):821-5
references.pmid: 8176446
references.citation: Aust N Z J Psychiatry. 2002 Apr;36(2):198-204
references.pmid: 11982540
references.citation: Neuroreport. 1999 Sep 9;10(13):2691-8
references.pmid: 10511425
references.citation: Prog Brain Res. 1996;107:379-402
references.pmid: 8782532
references.citation: Physiol Behav. 2012 Feb 28;105(4):925-32
references.pmid: 22108508