Memory formation under stress: Quantity and quality
Stress shapes memory. Depending on the timing of the stress exposure facilitating and impairing effects of stress are reported on how much is learned and remembered. Beyond such stress-induced changes in the quantity of memory, recent research suggests that stress also affects the contribution of multiple memory systems to performance. Under stress, rigid 'habit' memory gets favored over more flexible 'cognitive' memory. Thus, stress has an impact on the way we learn and remember, that is the quality of memory. This shift between different behavioral strategies on 'environmental demands' may facilitate adaptive responses. Here, we review stress effects on both quantity and quality of memory and address possible implications of these effects for the understanding of stress-related psychiatric disorders.
Lars Schwabe, Oliver T. Wolfa and Melly S. Oitz
Neurosciences & Biobehavioral Research, available online November 19, 2009
http://www.sciencedirect.com/ (for subscribers only)
November 2009

The trauma of psychosis: Posttraumatic stress disorder and recent onset psychosis
Clinical investigators have argued that the experience of a recent onset of psychosis is an event of such severity that it can lead to posttraumatic stress disorder (PTSD), or at least to PTSD symptoms. The traumagenic elements of the psychotic experience may relate to the distressing nature of psychotic symptoms, components of treatment, or both. However, this hypotheses has not been fully empirically evaluated. In particular, the importance of the DSM-IV A1 (perception of threat) and A2 (negative emotion at time of event) criteria for a traumatic event due to a psychotic episode has not been assessed. To address this question, 38 clients in treatment for recent onset of psychosis were interviewed to identify distressing experiences related to the episode, with PTSD assessed (including A1/A2 criteria) related to those events. More than one-half of the participants reported intense distress related to psychotic symptoms or treatment experiences, with 66% meeting symptom criteria for the PTSD syndrome (regardless of A1/A2), and 39% meeting full diagnostic criteria for PTSD (including A1/A2).
Schizophrenia Research, available online November 24, 2009
Kim T. Muesera, Weili Lue, Stanley D. Rosenberga and Rosemarie Wolfea
http://www.sciencedirect.com/ (for subscribers only)
November 2009

The Risk of Posttraumatic Stress Disorder After Trauma Depends on Traumatic Load and the Catechol-O-Methyltransferase Val Met Polymorphism
The risk for posttraumatic stress disorder (PTSD) depends on the number of traumatic event types experienced in a dose-response relationship, but genetic factors are known to also influence the risk of PTSD. The catechol-O-methyltransferase (COMT) Val158Met polymorphism has been found to affect fear extinction and might play a role in the etiology of anxiety disorders. Traumatic load and lifetime and current diagnosis of PTSD and COMT genotype were assessed in a sample of 424 survivors of the Rwandan Genocide living in the Nakivale refugee camp in southwestern Uganda. Higher numbers of different lifetime traumatic event types led to a higher prevalence of lifetime PTSD in a dose-response relationship. However, this effect was modulated by the COMT genotype: whereas Val allele carriers showed the typical dose-response relationship, Met/Met homozygotes exhibited a high risk for PTSD independently of the severity of traumatic load.
Biological Psychiatry, available online November 27, 2009
Iris-Tatjana Kolassa, Stephan Kolassa, Verena Ertl, Andreas Papassotiropoulos and Dominique J.-F. De Quervain
http://www.sciencedirect.com/ (for subscribers only)
November 2009

Emerging treatments for PTSD
Recent innovations in posttraumatic stress disorder (PTSD) research have identified new treatments with significant potential, as well as novel enhancements to empirically-validated treatments. This paper reviews emerging psychotherapeutic and pharmacologic interventions for the treatment of PTSD. It examines the evidence for a range of interventions, from social and family-based treatments to technological-based treatments. It describes recent findings regarding novel pharmacologic approaches including propranolol, ketamine, prazosin, and methylenedioxymethamphetamine. Special emphasis is given to the description of virtual reality and D-cycloserine as enhancements to prolonged exposure therapy.
Clinical Psychology Review, Articles in Press, available online 10 September 2009
Judith Cukor, Josh Spitalnick, JoAnn Difede, Albert Rizzoand Barbara O. Rothbaum
Journal of Anxiety Disorders
http://www.sciencedirect.com/ (for subscribers only)
October 2009

Explosive anger as a response to human rights violations in post-conflict Timor-Leste
Over several decades, clinicians have documented a pattern of explosive anger amongst survivors of gross human rights violations. Yet there is a dearth of epidemiological research investigating explosive anger in post-conflict countries. In the present study undertaken in Timor-Leste between March and November 2004, we identified an indigenous descriptor for explosive anger, including this index in the East Timor Mental Health Epidemiological Needs Study, a small area total population survey of 1544 adults living in an urban and a rural area. Other measures included indices of past trauma events, post-traumatic stress and general psychological distress, and socio-demographic variables. We found that 38% of the population reached the defined threshold of one attack of explosive anger a month (average = 1 episode every 2-3 days). Only a minority of persons with explosive anger reached threshold scores for post-traumatic stress and general psychological distress. High levels of trauma exposure represented the strongest predictor of explosive anger.
Social Science & Medicine, Volume 69, pp 670-677, available online 17 July 2009
Derrick Silove, Robert Brooks, Catherine Robina Bateman Steel, Zachary Steel, Kalhari Hewage, James Rodger and Ian Soosay
http://www.sciencedirect.com/ (for subscribers only)
October 2009

A strategy for the development of biomarker tests for PTSD
Currently, the diagnosis for PTSD is established on the basis of a patient's clinical history, mental status examination, duration of symptoms, and clinician administered symptom checklists or patient self-reports. However, there are no available laboratory biomarker tests for PTSD. To begin intervention at the earliest possible time, priority must be given to developing objective approaches to determine the presence of PTSD. Thus, a simple blood test or a biomarker that could detect PTSD in its earliest and potentially most treatable stages would be beneficial for physicians and patients. Currently, many potential biomarkers have been identified in the animal model or in patients with PTSD. But those biomarkers have not been well validated. Here, we hypothesize the development of a strategy for the identification of a biomarker for PTSD. This strategy involves pre-clinical screening, analytical validations and clinical validations. This strategy will enhance not only the study of the molecular mechanisms of PTSD, but also the translation of basic science to clinical implications.
Medical Hypothesis, Volume 73, Issue 3, pages 404-409
Lei Zhang, He Li, David Benedek, Xiaoxia Li and Robert Ursano
http://www.sciencedirect.com/ (for subscribers only)
October 2009

Clinically significant avoidance of public transport following the London Bombings: Travel Phobia or Subthreshold Posttraumatic Stress Disorder?
Following the London bombings of 7th July 2005 a "screen and treat" program was set up with the aim of providing rapid treatment for psychological responses in individuals directly affected. The present study found that 45% of the 596 respondents to the screening program reported phobic fear of public transport in a screening questionnaire. The screening program identified 255 bombing survivors who needed treatment for a psychological disorder. Of these, 20 (8%) suffered from clinically significant travel phobia. However, many of these individuals also reported symptoms of posttraumatic stress disorder [PTSD]. Comparisons between the travel phobia group and a sex-matched group of bombing survivors with PTSD showed that the travel phobic group reported fewer re-experiencing and arousal symptoms on the Trauma Screening Questionnaire (Brewin et al., 2002). doi:10.1016/j.janxdis.2009.07.023
Rachel V. Handley, Paul M. Salkovskis, Peter Scragg and Anke
Journal of Anxiety Disorders
http://www.sciencedirect.com/ (for subscribers only)
August 2009

A model of suicidal behavior in war veterans with posttraumatic mood disorder.
Many wars have been fought during the history of civilization. Many war veterans have symptoms of posttraumatic stress disorder (PTSD) and major depressive disorder (MDD) including suicidal ideation and behavior. PTSD is frequently comorbid with MDD. The authors has previously proposed that some or all individuals diagnosed with comorbid PTSD and MDD have a separate psychobiological condition that can be termed "posttraumatic mood disorder" (PTMD). Individuals with comorbid PTSD and MDD are characterized by greater severity of symptoms, increased suicidality and the higher level of impairment in social and occupational functioning compared to individuals with PTSD alone or MDD alone. Neurobiological evidence supporting the concept of PTMD includes the findings from neuroendocrine challenge, cerebrospinal fluid, neuroimaging, sleep and other studies. In this paper, he proposes a model of suicidal behavior in war veterans with PTMD. The model consists of the following components: (1) genetic factors; (2) prenatal development; (3) biological and psychosocial influences from birth to mobilization/deployment; (4) mobilization/pre-deployment stress; (5) combat stress, traumatic brain injury, and physical injury; (6) post-deployment stress; (7) biological and psychosocial influences after the deployment; (8) trigger (precipitant) of a suicidal act; and (9) suicidal act. on. doi:10.1016/j.mehy.2008.12.052
Leo Sher
Medical Hypotheses
http://www.sciencedirect.com/ (for subscribers only)
August 2009

Acceptance and Commitment Therapy for Treatment-Resistant Posttraumatic Stress Disorder: a case study
An adult woman with chronic posttraumatic stress disorder (PTSD) and major depressive disorder who was nonresponsive to 20 sessions of cognitive behavior therapy (CBT) is presented in this case study. Two months after her CBT trial, she was treated with 21 sessions of Acceptance and Commitment Therapy (ACT) for PTSD. Measurements of PTSD severity, depression, anxiety, psychological flexibility and trauma-related thoughts and beliefs were taken at pretreatment, after Sessions 8 and 16, and at posttreatment. Results showed significant reduction on all measures throughout treatment, except for trauma-related thoughts and beliefs, which did not decrease until near the end of treatment. Strengths, limitations, and future directions are discussed. doi:10.1016/j.cbpra.2008.10.002
Michael P. Twohig
Cognitive and Behavioral Practice
http://www.sciencedirect.com/ (for subscribers only)
August 2009

The lifetime prevalence of traumatic events and posttraumatic stress disorder in the Netherlands.
The authors state, that there is little information on the lifetime prevalence of traumatic events and posttraumatic stress disorder (PTSD) in the general population of the Netherlands. The present study focused specifically on establishing estimates of lifetime prevalence rates of exposure to potentially traumatic events and PTSD in the general Dutch population. A national representative sample of 1087 adults aged 18 to 80 years was selected using random digital dialing and then surveyed by telephone using the Composite International Diagnostic Interview (CIDI) to determine the prevalence of trauma and DSM-IV PTSD. The lifetime prevalence of any potential trauma was 80,7%, and the lifetime prevalence of PTSD was 7,4%. Women and younger persons showed higher risk of PTSD. It was concluded that PTSD is a fairly common disorder and exposure to trauma is high throughout the population. Unexpectedly, prevalence rates resemble those found in the United States and are higher than in several other European countries.
Giel-Jan de Vries and Miranda Olff
Journal of Traumatic Stress, Volume 22, N 4, August 2009, pp.259-267
PDF [91.2 kB]
August 2009

Brief measure of posttraumatic stress reactions: impact of Event Scale-6
The Impact of event Scale-revised (IES-R) is one of the most widely used measures of posttraumatic stress reactions. However, for some purposes, such as large epidemiological studies, there is a need for briefer instruments. The aim of the study was to develop and validate an abbreviated version of IES-R that could capture the three current symptom clusters of posttraumatic stress disorder (PTSD). The IES-6 appears to be a robust brief measure of posttraumatic stress reactions. It may be useful for research in epidemiological studies, and it may also have a role as a screening instrument in clinical practice.
Siri Thoresen, Kristian Tambs, Ajmal Hussain, Trond Heir, Venke A. Johansen, Jonathan I. Bisson.
Soc Psychiat. Epidemiol. DOI 10.1007/s00127-009-0073-x
PDF [172.8 kB]
May 2009

Image credits