title: Right temporal cortical hypertrophy in resilience to trauma: an MRI study.
abstract: BACKGROUND
  In studies employing physiological measures such as magnetic resonance imaging (MRI), it is often hard to distinguish what constitutes risk-resilience factors to posttraumatic stress disorder (PTSD) following trauma exposure and what the effects of trauma exposure and PTSD are.
  
  
  OBJECTIVE
  We aimed to investigate whether there were observable morphological differences in cortical and sub-cortical regions of the brain, 7-8 years after a single potentially traumatic event.
  
  
  METHODS
  Twenty-four participants, who all directly experienced the 2004 Indian Ocean Tsunami, and 25 controls, underwent structural MRI using a 3T scanner. We generated cortical thickness maps and parcellated sub-cortical volumes for analysis.
  
  
  RESULTS
  We observed greater cortical thickness for the trauma-exposed participants relative to controls, in a right lateralized temporal lobe region including anterior fusiform gyrus, and superior, middle, and inferior temporal gyrus.
  
  
  CONCLUSIONS
  We observed greater thickness in the right temporal lobe which might indicate that the region could be implicated in resilience to the long-term effects of a traumatic event. We hypothesize this is due to altered emotional semantic memory processing. However, several methodological and confounding issues warrant caution in interpretation of the results.
authors.affiliation: Institute of Psychology, University of Oslo, Oslo, Norway; sevenius.nilsen@gmail.com.
authors.forename: André Sevenius
authors.initials: AS
authors.lastname: Nilsen
authors.affiliation: Institute of Psychology, University of Oslo, Oslo, Norway.|Diakonhjemmet Hospital, Oslo, Norway.
authors.forename: Eva
authors.initials: E
authors.lastname: Hilland
authors.affiliation: Innlandet Hospital Trust, Brumunddal, Norway.
authors.forename: Norunn
authors.initials: N
authors.lastname: Kogstad
authors.affiliation: Institute of Clinical Medicine, University of Oslo, Oslo, Norway.|Norwegian Center for Violence and Traumatic Stress Studies, Oslo, Norway.
authors.forename: Trond
authors.initials: T
authors.lastname: Heir
authors.affiliation: Institute of Clinical Medicine, University of Oslo, Oslo, Norway.|Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway.
authors.forename: Edvard
authors.initials: E
authors.lastname: Hauff
authors.affiliation: Innlandet Hospital Trust, Brumunddal, Norway.|Faculty of Public Health, Hedmark University College, Elverum, Norway.
authors.forename: Lars
authors.initials: L
authors.lastname: Lien
authors.affiliation: Institute of Psychology, University of Oslo, Oslo, Norway.
authors.forename: Tor
authors.initials: T
authors.lastname: Endestad
keywords: MRI; PTSD; Psychotraumatology; natural disaster; psychological distress; traumatic event