title: Biological responses to trauma and the development of intrusive memories: an analog study with the trauma film paradigm.
abstract: Evidence suggests that previous trauma reduces the cortisol response to subsequent stressors. We examined the relation of this response to intrusive memory, and the potential moderating roles of sympathetic reactions. Pre-existing trauma-related factors and the cardiac defense response were assessed before 58 healthy participants viewed a trauma film. Salivary cortisol and alpha-amylase (sAA) were collected pre-, peri- and post-film. Intrusive memories about the film were recorded for a week. Cortisol increased whereas sAA decreased after the film. Those with more recent traumatic experiences and greater subclinical PTSD symptoms had lower cortisol concentration post-film. Lower cortisol levels predicted greater vividness of intrusions. Positive correlations between cortisol and the frequency of intrusion were only present among individuals with more sympathetic activations. These findings suggest the contribution of insufficient cortisol secretion to over-consolidation of traumatic memory, and highlight the variation attributable to individual differences and different memory characteristics.
authors.affiliation: Clinical, Educational and Health Psychology, University College London, Gower Street, London WC1E 6BT, UK.
authors.forename: Chia-Ying
authors.initials: CY
authors.lastname: Chou
authors.affiliation: Clinical Psychology and Psychotherapy, Psychology Institute, University of Zurich, Binzmühlestrasse 14/Box 26, CH-8050 Zurich, Switzerland; Institute of Epidemiology and Health Care, University College London, Gower Street, London WC1E 6BT, UK.
authors.forename: Roberto
authors.initials: R
authors.lastname: La Marca
authors.affiliation: Institute of Epidemiology and Health Care, University College London, Gower Street, London WC1E 6BT, UK.
authors.forename: Andrew
authors.initials: A
authors.lastname: Steptoe
authors.affiliation: Clinical, Educational and Health Psychology, University College London, Gower Street, London WC1E 6BT, UK. Electronic address: c.brewin@ucl.ac.uk.
authors.forename: Chris R
authors.initials: CR
authors.lastname: Brewin
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000032:analysis*; D008297:Male; D008568:Memory / Q000502:physiology*; D012463:Saliva / Q000737:chemistry; D055291:Salivary alpha-Amylases / Q000032:analysis; D013313:Stress Disorders, Post-Traumatic / Q000503:physiopathology*; D013564:Sympathetic Nervous System / Q000503:physiopathology*; D055815:Young Adult
chemical_list: D055291:Salivary alpha-Amylases; D006854:Hydrocortisone
keywords: Alpha-amylase; Cardiovascular defense response; Cortisol; Intrusions; Posttraumatic stress disorder; Trauma film