Differentiating biological correlates of risk, PTSD, and resilience following trauma exposure

Reduced pre-attentive threat versus nonthreat signal discrimination in clinically healthy military personnel with recurrent combat exposure history: A preliminary event-related potential (ERP) study

Evidence now suggests that traumatic-stress impacts brain functions even in the absence of acute-onset post-traumatic stress disorder (PTSD) symptoms. These neurophysiological changes have also been suggested to account for increased risks of PTSD symptoms later developing in the aftermath of subsequent trauma. However, surprisingly few studies have explicitly examined brain function dynamics in high-risk populations, such as combat exposed military personnel without diagnosable PTSD. To extend available research, facial expression sensitive N170 event-related potential (ERP) amplitudes were examined in a clinically healthy sample of active service military personnel with recurrent combat exposure history. Consistent with several established theories of delayed-onset PTSD vulnerability, higher N170 amplitudes to backward-masked fearful and neutral facial expressions correlated with higher levels of past combat exposure. Significantly elevated amplitudes to nonthreatening neutral facial expressions also resulted in an absence of normal threat-versus-nonthreat signal processing specificity. While a modest sample size and cross-sectional design are key limitations here, ongoing prospective-longitudinal follow-ups may shed further light on the precise aetiology and prognostic utility of these preliminary findings in the near future.

Resilience after combat: A prospective, longitudinal study of Marines and Navy Corpsmen

Resilience is common, yet our understanding of key biopsychosocial and environmental correlates is limited. Additionally, perceived resilience is often conflated with absence of psychiatric symptoms. Here we leverage prospective, longitudinal data from 1835 Marines and Navy Corpsmen to examine predictors of perceived resilience 3 months after a combat deployment, while controlling for pre-deployment and concurrent psychiatric symptoms. Marines and Corpsmen did not differ significantly on psychosocial or clinical factors, and 50.4% reported high perceived resilience after deployment. Across groups, the strongest predictors of post-deployment perceived resilience were pre-deployment perceived resilience, positive emotions, and social support. Concurrent depression was the only clinical symptom negatively associated with perceived resilience. Our findings suggest that perceived resilience is a multi-dimensional construct that involves both psychosocial and personality factors, including but not limited to low psychopathology. Notably, establishing strong social support networks and encouraging positive emotions may help promote resilience following deployment.

Flexible emotional regulation typology: associations with PTSD symptomology and trait resilience

BACKGROUND

Multiple factors influence posttraumatic stress disorder (PTSD) risk in trauma exposed individuals. An established association exists between trait resilience and decreased PTSD distress and between emotion regulation (ER) ability/flexibility and trait resilience. Typologies in ER ability/flexibility, associated with trait resilience and PTSD experience, could explain the difference in risk. This study aimed to explore the relationship between ER ability, ER flexibility, context sensitivity, resilience, and PTSD.

METHODS

Data from N = 563 trauma exposed UK residents was used in a latent profile analysis (LPA) and membership in the resultant profiles was explored in a logistic regression of sociodemographics, resilience, and PTSD symptomology.

RESULTS

Analysis showed 2 latent profiles (High Flexibility, Low Flexibility) typified by emotion regulation ability and context sensitivity. Members of the Low Flexibility profile were more likely to be younger, male, endorsing less trait resilience, and experiencing negative cognition/mood and hyperarousal PTSD symptomology.

CONCLUSIONS

Difficulties in ER ability and flexibility could be improved with targeted learning in a therapeutic or home setting, potentially increasing trait resilience after trauma exposure and reducing PTSD distress.

Functional neuroimaging of resilience to trauma: convergent evidence and challenges for future research

Resilience is broadly defined as the ability to adapt successfully following stressful life events. Here, we review functional MRI studies that investigated key psychological factors that have been consistently linked to resilience to severe adversity and trauma exposure. These domains include emotion regulation (including cognitive reappraisal), reward responsivity, and cognitive control. Further, we briefly review functional imaging evidence related to emerging areas of study that may potentially facilitate resilience: namely social cognition, active coping, and successful fear extinction. Finally, we also touch upon ongoing issues in neuroimaging study design that will need to be addressed to enable us to harness insight from such studies to improve treatments for - or, ideally, guard against the development of - debilitating post-traumatic stress syndromes.

Resilience by design: How nature, nurture, environment, and microbiome mitigate stress and allostatic load

Resilience to psychological stress is defined as adaption to challenging life experiences and not the absence of adverse life events. Determinants of resilience include personality traits, genetic/epigenetic modifications of genes involved in the stress response, cognitive and behavioral flexibility, secure attachment with a caregiver, social and community support systems, nutrition and exercise, and alignment of circadian rhythm to the natural light/dark cycle. Therefore, resilience is a dynamic and flexible process that continually evolves by the intersection of different domains in human’s life; biological, social, and psychological. The objective of this minireview is to summarize the existing knowledge about the multitude factors and molecular alterations that result from resilience to stress response. Given the multiple contributing factors in building resilience, we set out a goal to identify which factors were most supportive of a causal role by the current literature. We focused on resilience-related molecular alterations resulting from mind-body homeostasis in connection with psychosocial and environmental factors. We conclude that there is no one causal factor that differentiates a resilient person from a vulnerable one. Instead, building resilience requires an intricate network of positive experiences and a healthy lifestyle that contribute to a balanced mind-body connection. Therefore, a holistic approach must be adopted in future research on stress response to address the multiple elements that promote resilience and prevent illnesses and psychopathology related to stress allostatic load.

The brain at rest: Exploratory Neurophysiological Findings Among Men With Histories of Childhood Sexual Abuse

Purpose

There is a lack of research on childhood sexual abuse (CSA) experienced by men, with even less research examining long term neurophysiological repercussions. This study explored the neurophysiology of the brain at rest to examine the influence of CSA on resting state functional connectivity (RSFC) into adulthood.

Methods

RSFC was examined with functional magnetic resonance imaging (fMRI) within the default mode, salience and limbic networks in men with CSA histories, with and without post-traumatic stress disorder (PTSD; CSA + PTSD n = 7, CSA-PTSD n = 9), and men without a CSA history nor PTSD (n = 13).

Results

CSA + PTSD participants had increased functional connectivity (FC) in the medial prefrontal cortex (mPFC) from the default mode network seed compared to participants with CSA-PTSD. Both CSA groups showed significantly less FC in the striatal-thalamic circuits of the salience network than the control group. Similarly, the robust FC between the bilateral amygdalae and the mPFC that was notable in control participants, was not exhibited in participants who experienced CSA with or without PTSD histories.

Conclusions

These findings demonstrate that intrinsic neurophysiological differences in limbic, salience and default mode network connectivity are apparent even during a resting state between the groups of participants. This is preliminary evidence of long-term neurophysiological effects of CSA in men with PTSD, and even in those without. Importantly, these findings can validate the lived experiences of males with CSA histories and guide researchers and clinicians to potential avenues to support their well-being.

Traumatic Autobiographical Memories: Preliminary fMRI Findings Among Men With Histories of Childhood Sexual Abuse

Childhood sexual abuse (CSA) is associated with autobiographical memory (AM) disturbances. AM is important for future thinking, sense of self, and coping with negative emotions. CSA is under-researched among men, with research examining long-term neural correlates limited even further. This study explored the neural correlates of re-experiencing traumatic/negative memories to examine the influence of CSA on AM into adulthood. Fifteen males who experienced CSA, with and without posttraumatic stress disorder (PTSD; CSA+PTSD, n = 6; CSA–PTSD, n = 9) and control males without CSA histories nor PTSD (n = 11) completed a script-driven imagery paradigm during functional magnetic resonance imaging (fMRI). Males with CSA histories, with and without PTSD, processed their negative autobiographical memories with less activation compared to control males. The CSA+PTSD group of males had less activation in the left superior occipital, left superior parietal and left parahippocampal gyri compared to control participants. The CSA–PTSD group had reduced activation in the same regions to a lesser extent. This study provides preliminary empirical evidence to suggest CSA impacts AM for traumatic experiences, and the impact is notable even for men who experienced CSA but do not have PTSD. This study highlights the need for more research with men who have experienced CSA, so that, we can fully understand the neural correlates of emotional memories, and better support the mental health and continued wellness of men who experienced CSA.

Clinical utility of PTSD, resilience, sleep, and blast as risk factors to predict poor neurobehavioral functioning following traumatic brain injury: A longitudinal study in U.S. military service members

PURPOSE

This study examined the clinical utility of post-traumatic stress disorder (PTSD), low resilience, poor sleep, and lifetime blast exposure as risk factors for predicting future neurobehavioral outcome following traumatic brain injury (TBI).

METHODS

Participants were 591 U.S. military service members and veterans who had sustained a TBI (n = 419) or orthopedic injury without TBI (n = 172). Participants completed the Neurobehavioral Symptom Inventory, PTSD Checklist, and the TBI-Quality of Life (TBI-QOL) scale at baseline and follow-up.

RESULTS

Using the four risk factors at baseline, 15 risk factor combinations were examined by calculating odds ratios to predict poor neurobehavioral outcome at follow-up (i.e., number of abnormal scores across five TBI-QOL scales [e.g., Fatigue, Depression]). The vast majority of risk factor combinations resulted in odds ratios that were considered to be clinically meaningful (i.e., ≥ 2.5) for predicting poor outcome. The risk factor combinations with the highest odds ratios included PTSD singularly, or in combination with poor sleep and/or low resilience (odds ratios = 4.3-72.4). However, poor sleep and low resilience were also strong predictors in the absence of PTSD (odds ratios = 3.1-29.8).

CONCLUSION

PTSD, poor sleep, and low resilience, singularly or in combination, may be valuable risk factors that can be used clinically for targeted early interventions.

Self-Compassion in Irish Social Work Students: Relationships between Resilience, Engagement and Motivation

Self-compassion recognises a meaning of life’s suffering, aligning with existential positive psychology. Although this construct is known to protect our mental health, how to augment self-compassion remains to be evaluated. Social work students suffer from high rates of mental health problems; however, research into self-compassion in this population remains to be developed. This study aimed to evaluate (i) relationships between self-compassion and more traditional positive constructs—resilience, engagement and motivation, and (ii) differences of these constructs between the levels of studies to inform how self-compassion can be enhanced in social work students. A total of 129 Irish social work students completed self-report scales regarding self-compassion, resilience, engagement and motivation. Correlation, regression and one-way MANOVA were conducted. Self-compassion was associated with gender, age, resilience, engagement and intrinsic motivation. Resilience and intrinsic motivation were significant predictors of self-compassion. There was no significant difference in the levels of these constructs between the levels of studies. Findings suggest that social work educators across different levels can strengthen students’ resilience and intrinsic motivation to cultivate the students’ self-compassion. Moreover, the close relationships between self-compassion, resilience and intrinsic motivation indicate that orienting students to the meaning of the studies helps their mental health.

A Comprehensive Resiliency Framework: Theoretical Model, Treatment, and Evaluation

BACKGROUND

There is heterogeneity in conceptualizations of resiliency, and there is, to date, no established theoretically driven resiliency assessment measure that aligns with a targeted resiliency intervention. We operationalize resiliency as one's ability to maintain adaptive functioning in response to the ongoing, chronic stress of daily living, and we use a novel resiliency measure that assesses the target components of an evidence based resiliency intervention. We present our resiliency theory, treatment model, and corresponding assessment measure (Current Experience Scale; CES).

METHODS

To establish the psychometric properties of the CES, we report the factor structure and internal consistency reliability (N = 273). Among participants in our resiliency intervention (N = 151), we explored construct validity in terms of associations with theoretical model constructs, a validated resiliency measure, and sensitivity to change from before to after the intervention.

RESULTS

Results indicated that a 23-item, 6-factor solution was a good fit to the data (RMSEA = .08, CFI = .97; TLI =.96) and internal consistency was good (α = .81 to .95). The CES showed correlations in the expected direction with resiliency model constructs (all p's < .001) and significant post intervention improvements.

CONCLUSION

Our resiliency theory, treatment model, and outcome appear aligned; the CES demonstrated promise as a psychometrically sound outcome measure for our resiliency intervention and may be used in future longitudinal studies and resiliency building interventions to assess individuals' resiliency to adapt to ongoing stress.

Resilience in the age of COVID-19

Resilience is broadly defined as the ability to bounce back from adversity or trauma. Recent advances in resilience research have shifted away from merely describing individual characteristics towards focusing on the complex interactions between individuals and their dynamic personal, community and cultural contexts. It is clear that resilience involves both neurobiological and cultural processes. Neurobiological contributions include genes, epigenetics, stress-response systems, the immune system and neural circuitry. Culture helps to elucidate collective systems of belief and accepted positive adaptations. Importantly, resilience can also be affected by evidence-based interventions and deliberate practice on the part of the individual. This review seeks to understand resilience as a complex and active process that is shaped by neurobiological profiles, developmental experiences, cultural and temporal contexts, and practical training. It uses the COVID-19 pandemic as a case example to better understand individual and group responses to tragedy. We suggest practical recommendations to help populations around the world cope and recover from the global threat of COVID-19.

Individualized Prediction of PTSD Symptom Severity in Trauma Survivors From Whole-Brain Resting-State Functional Connectivity

Previous studies have demonstrated relations between spontaneous neural activity evaluated by resting-state functional magnetic resonance imaging (fMRI) and symptom severity in post-traumatic stress disorder. However, few studies have used brain-based measures to identify imaging associations with illness severity at the level of individual patients. This study applied connectome-based predictive modeling (CPM), a recently developed data-driven and subject-level method, to identify brain function features that are related to symptom severity of trauma survivors. Resting-state fMRI scans and clinical ratings were obtained 10-15 months after the earthquake from 122 earthquake survivors. Symptom severity of post-traumatic stress disorder features for each survivor was evaluated using the Clinician Administered Post-traumatic Stress Disorder Scale (CAPS-IV). A functionally pre-defined atlas was applied to divide the human brain into 268 regions. Each individual's functional connectivity 268 × 268 matrix was created to reflect correlations of functional time series data across each pair of nodes. The relationship between CAPS-IV scores and brain functional connectivity was explored in a CPM linear model. Using a leave-one-out cross-validation (LOOCV) procedure, findings showed that the positive network model predicted the left-out individual's CAPS-IV scores from resting-state functional connectivity. CPM predicted CAPS-IV scores, as indicated by a significant correspondence between predicted and actual values (r = 0.30, P = 0.001) utilizing primarily functional connectivity between visual cortex, subcortical-cerebellum, limbic, and motor systems. The current study provides data-driven evidence regarding the functional brain features that predict symptom severity based on the organization of intrinsic brain networks and highlights its potential application in making clinical evaluation of symptom severity at the individual level.

Neuropeptide Y plasma levels and suicidal behavior in combat veterans

War veterans are at increased risk of suicide that may be related to deployment and/or post-deployment stressors and to adjustment-related factors. The aim of this study was to examine whether levels of plasma neuropeptide Y (NPY) might distinguish combat veterans who have made a post-deployment suicide attempt from those who have never made a suicide attempt. We focused on NPY because of prior findings linking NPY with the neurobiology of resilience, stress-related and other disorders, and suicidal behavior. Demographic and clinical parameters of suicide attempters and non-attempters were assessed and plasma NPY was determined by radioimmunoassay. NPY levels were higher among attempters in comparison to non-attempters, controlling for sex and body-mass index. Suicide attempters had higher Scale for Suicidal Ideation (SSI) scores than non-attempters. There was a positive correlation between NPY levels and SSI scores among non-attempters but not among attempters. Likewise, NPY levels positively correlated with Brown-Goodwin Aggression Scale scores among suicide attempters but not among non-attempters. This is the first demonstration of altered plasma NPY levels in association with suicide attempt history and suicidal ideation in veterans. Our findings suggest that clinical differences between combat veterans with or without a history of suicide attempt may have a neurobiological origin.

NTRK2 methylation is related to reduced PTSD risk in two African cohorts of trauma survivors

Extensive pharmacologic, genetic, and epigenetic research has linked the glucocorticoid receptor (GR) to memory processes, and to risk and symptoms of posttraumatic stress disorder (PTSD). In the present study we investigated the epigenetic pattern of 12 genes involved in the regulation of GR signaling in two African populations of heavily traumatized individuals: Survivors of the rebel war in northern Uganda (n = 463) and survivors of the Rwandan genocide (n = 350). The strongest link between regional methylation and PTSD risk and symptoms was observed for NTRK2, which encodes the transmembrane receptor tropomyosin-related kinase B, binds the brain-derived neurotrophic factor, and has been shown to play an important role in memory formation. NTRK2 methylation was not related to trauma load, suggesting that methylation differences preexisted the trauma. Because NTRK2 methylation differences were predominantly associated with memory-related PTSD symptoms, and because they seem to precede traumatic events, we next investigated the relationship between NTRK2 methylation and memory in a sample of nontraumatized individuals (n = 568). We found that NTRK2 methylation was negatively associated with recognition memory performance. Furthermore, fMRI analyses revealed NTRK2 methylation-dependent differences in brain network activity related to recognition memory. The present study demonstrates that NTRK2 is epigenetically linked to memory functions in nontraumatized subjects and to PTSD risk and symptoms in traumatized populations.

What's Love Got to do with it: Role of oxytocin in trauma, attachment and resilience

Oxytocin (OT) is a neurohypophysial hormone and neuropeptide produced by the hypothalamus and released by the pituitary gland. It has multiple physiological roles including stimulation of parturition and lactation, and promotion of pro-adaptive social behaviors necessary for mammalian survival. OT interacts with one receptor subtype: the OT receptor (OTR) which, upon stimulation, triggers different intracellular signal transduction cascades to mediate its physiological actions. Preclinical studies show that OT regulates social behaviors such as pair bonding, recognition and social interaction. It also coordinates the activation of the hypothalamic-pituitary-adrenal (HPA) axis and the release of corticotrophin-releasing hormone. Further evidence suggests that OT plays an important role in regulating caloric intake and metabolism, and in maintaining electrolyte and cardiovascular homeostasis. OT is also involved in attenuating the neurophysiological and neurochemical effects of trauma on the brain and body by facilitating both physical attachment such as wound healing, and psychological/social attachment, thereby increasing resilience to subsequent traumatic events. Clinical trials have reported that intranasal administration of OT provides therapeutic benefits for patients diagnosed with traumatic stress-related diseases such as major depressive disorders and post-traumatic stress disorder. OT's therapeutic benefits may result from context-dependent interactions with key neural pathways (social, cognitive, and reward), neurotransmitters (dopamine, norepinephrine, serotonin, and endogenous opioids), and biomarkers (adrenocorticotropic hormone, cortisol, and dehydroepiandrosterone sulfate), that lead to a decrease in stress -associated behaviors, and facilitate post-traumatic growth, ultimately leading to increased resilience, through improved social cohesion and attachment. OT induced-augmentation of physical and cognitive resilience may play a significant role in both the prevention of, and improved clinical outcomes for, traumatic stress-related disorders following either acute or enduring traumatic experiences.

The Role of Perceived Authenticity in Psychological Recovery from Collective Trauma

Introduction: Previous research demonstrates that perceived authenticity is positively associated with psychological health and security in the face of threats. The current research extends this work by testing whether perceived authenticity promotes recovery from the negative mental health consequences of collective trauma (e.g., a natural disaster).

Methods: We recruited a sample of undergraduates (N = 570), many of whom reported direct or indirect exposure to Hurricane Harvey, to complete surveys at two time points. We assessed exposure to the disaster, acute stress, post-traumatic stress, coping, and authenticity twice, once approximately 1 month after Hurricane Harvey (Time 1) and again approximately 9 weeks after Hurricane Harvey (Time 2).

Results: We employed multilevel modelling to explore whether authenticity would aid in recovery from collective trauma. Results showed that perceived authentic living at Time 1 predicted a variety of indicators of stress related to the hurricane at Time 2. Specifically, those participants who reported low authentic living at Time 1 reported greater levels of stress at Time 2, compared to individuals who reported higher levels of authentic living. Importantly, these effects remained even when controlling for known predictors of stress (e.g., levels of stress at Time 1 and coping strategies).

Discussion: Findings provide preliminary insight into authenticity as a part of a likely larger network of interrelated psychosocial qualities that have the potential to help one navigate recovery from trauma.

Exploring memory function in earthquake trauma survivors with resting-state fMRI and machine learning

BACKGROUND

Traumatized earthquake survivors may develop poor memory function. Resting-state functional magnetic resonance imaging (rs-fMRI) and machine learning techniques may one day aid the clinical assessment of individual psychiatric patients. This study aims to use machine learning with Rs-fMRI from the perspectives of neurophysiology and neuroimaging to explore the association between it and the individual memory function of trauma survivors.

METHODS

Rs-fMRI data was acquired for eighty-nine survivors (male (33%), average age (SD):45.18(6.31) years) of Wenchuan earthquakes in 2008 each of whom was screened by experienced psychiatrists based on the clinician-administered post-traumatic stress disorder (PTSD) scale (CAPS), and their memory function scores were determined by the Wechsler Memory Scale-IV (WMS-IV). We explored which memory function scores were significantly associated with CAPS scores. Using simple multiple kernel learning (MKL), Rs-fMRI was used to predict the memory function scores that were associated with CAPS scores. A support vector machine (SVM) was also used to make classifications in trauma survivors with or without PTSD.

RESULTS

Spatial addition (SA), which is defined by spatial working memory function, was negatively correlated with the total CAPS score (r = - 0.22, P = 0.04). The use of simple MKL allowed quantitative association of SA scores with statistically significant accuracy (correlation = 0.28, P = 0.03; mean squared error = 8.36; P = 0.04). The left middle frontal gyrus and the left precuneus contributed the largest proportion to the simple MKL association frame. The SVM could not make a quantitative classification of diagnosis with statistically significant accuracy.

LIMITATIONS

The use of the cross-sectional study design after exposure to an earthquake and the leave-one-out cross-validation (LOOCV) increases the risk of overfitting.

CONCLUSION

Spontaneous brain activity of the left middle frontal gyrus and the left precuneus acquired by rs-fMRI may be a brain mechanism of visual working memory that is related to PTSD symptoms. Machine learning may be a useful tool in the identification of brain mechanisms of memory impairment in trauma survivors.

Genomics and psychological resilience: a research agenda

Although exposure to adversity increases risk for poor mental health outcomes, many people exposed to adversity do not develop such outcomes. Psychological resilience, defined broadly as positive emotional and/or behavioral adaptation to adversity, may be influenced by genetic factors that have remained largely unexplored in the era of large-scale genome-wide studies. In this perspective, we provide an integrative framework for studying human genome-wide variation underlying resilience. We first outline three complementary working definitions of psychological resilience-as a capacity, process, and outcome. For each definition, we review emerging empirical evidence, including findings from positive psychology, to illustrate how a resilience-based framework can guide novel and fruitful directions for the field of psychiatric genomics, distinct from the ongoing study of psychiatric risk and related traits. Finally, we provide practical recommendations for future genomic research on resilience, highlighting a need to augment cross-sectional findings with prospective designs that include detailed measurement of adversities and outcomes. A research framework that explicitly addresses resilience could help us to probe biological mechanisms of stress adaptation, identify individuals who may benefit the most from prevention and early intervention, and ascertain modifiable protective factors that mitigate negative outcomes even for those at high genetic risk.

Mechanisms of resiliency against depression following the Deepwater Horizon Oil Spill

Prior studies of oil spills have reported adverse impacts on mental health, but have not examined some potentially important moderators. In this cross-sectional analysis of n=38,361 responses to the 2010-2011 Gulf States Population Survey, we assessed the association of direct oil contact with depression severity following the Deepwater Horizon oil spill, and modification by self-mastery, emotional support, and cleanup participation using Tobit regression models accounting for the complex survey design. Oil contact was associated with increased depression severity. Among respondents with oil contact, depression was more severe for those reporting lower self-mastery. However, respondents with oil contact had lower depression severity if they participated in cleanup efforts, compared to exposed individuals who did not participate. This potential protective effect was larger for respondents with lower self-mastery. Our results are consistent with the notion that participation in recovery efforts may reduce depressive symptoms following oil spills among impacted individuals.

Childhood adversity and parent perceptions of child resilience

BACKGROUND

Adverse childhood experiences (ACEs) negatively impact health throughout the life course. For children exposed to ACEs, resilience may be particularly important. However, the literature regarding resilience, particularly the self-regulation aspect of resilience, is not often described in children with ACEs. Additionally, family and community factors that might help promote resilience in childhood may be further elucidated. We aimed to describe the relationship between ACEs and parent-perceived resilience in children and examine the child, family, and community-level factors associated with child resilience.

METHODS

Using the US-based, 2011-2012 National Survey of Children's Health, we examined adverse childhood experiences (NSCH-ACEs) as the main exposure. Affirmative answers to adverse experiences generated a total parent-reported NSCH-ACE score. Bivariate and multivariable logistic regression models were constructed for parent-perceived child resilience and its association with ACEs, controlling for child, family, and neighborhood-level factors.

RESULTS

Among 62,200 US children 6-17 years old, 47% had 0 ACEs, 26% had 1 ACE, 19% had 2-3 ACEs, and 8% had 4 or more ACEs. Child resilience was associated with ACEs in a dose-dependent relationship: as ACEs increased, the probability of resilience decreased. This relationship persisted after controlling for child, family, and community factors. Specific community factors, such as neighborhood safety (p < .001), neighborhood amenities (e.g., libraries, parks) (p < .01) and mentorship (p < .05), were associated with significantly higher adjusted probabilities of resilience, when compared to peers without these specific community factors.

CONCLUSIONS

While ACEs are common and may be difficult to prevent, there may be opportunities for health care providers, child welfare professionals, and policymakers to strengthen children and families by supporting community-based activities, programs, and policies that promote resilience in vulnerable children and communities in which they live.

Psychological resilience in U.S. military veterans: A 2-year, nationally representative prospective cohort study

Although many cross-sectional studies have examined the correlates of psychological resilience in U.S. military veterans, few longitudinal studies have identified long-term predictors of resilience in this population. The current prospective cohort study utilized data from a nationally representative sample of 2157 U.S. military veterans who completed web-based surveys in two waves (2011 and 2013) as part of the National Health and Resilience in Veterans Study (NHRVS). Cluster analysis of cumulative lifetime exposure to potentially traumatic events and Wave 2 measures of current symptoms of posttraumatic stress, major depressive, and generalized anxiety disorders was performed to characterize different profiles of current trauma-related psychological symptoms. Different profiles were compared with respect to sociodemographic, clinical, and psychosocial characteristics. A three-group cluster analysis revealed a Control group with low lifetime trauma exposure and low current psychological distress (59.5%), a Resilient group with high lifetime trauma and low current distress (27.4%), and a Distressed group with both high trauma exposure and current distress symptoms (13.1%). These results suggest that the majority of trauma-exposed veterans (67.7%) are psychologically resilient. Compared with the Distressed group, the Resilient group was younger, more likely to be Caucasian, and scored lower on measures of physical health difficulties, past psychiatric history, and substance abuse. Higher levels of emotional stability, extraversion, dispositional gratitude, purpose in life, and altruism, and lower levels of openness to experiences predicted resilient status. Prevention and treatment efforts designed to enhance modifiable factors such as gratitude, sense of purpose, and altruism may help promote resilience in highly trauma-exposed veterans.

Prevalence and predictors of posttraumatic stress symptoms in parents of children with ongoing treatment for cancer in South China: a multi-centered cross-sectional study

PURPOSE

Parents of children with ongoing cancer treatment are exposed to risks of developing posttraumatic stress symptoms (PTSS), but little is known about the prevalence and predictors of PTSS among Chinese parents of children with cancer. This study aimed to examine the predictors of PTSS, and explored the correlation of depression, resilience, and family functions with severe PTSS.

METHODS

This cross-sectional survey was conducted from May 2014 to September 2015 among the parents of cancer children treated in four general hospitals in South China. PTSS in the parents were measured using post-traumatic stress checklist-civilian version (PCL-C). Multiple regression analyses were performed to evaluate the predictive values of depression, resilience, family functioning, and the demographic variables for severe PTSS.

RESULTS

A total of 279 parents (192 mothers and 87 fathers) participated in the survey. Severe PTSS, as defined by a PCL-C score ≥50, were reported in 32.97% (n = 92) of the total participants, 26.44% (23/87) in the fathers and 35.94% (69/192) in the mothers. The level of PTSS was positively correlated with depression (r = 0.782, P < 0.01) and a poor general family function (r = 0.325, P < 0.01) and negatively correlated with resilience (r = -0.236, P < 0.01). Multivariate analyses indicated that depression, general family function, gender, and education level were significant predictive factors of severe PTSS in the overall parents, accounting for 64.2% of the variance in the prediction of PTSS (R ² = 0.642, F = 122.602, P = 0.000). For the mothers, depression and family function accounted for 66.5% of the variance in the prediction of PTSS (R ² = 0.665, F = 187.451, P = 0.000); for the fathers, depression and educational level accounted for 58.8% of the variance in the prediction of PTSS (R ² = 0.588, F = 59.829, P = 0.000).

CONCLUSION

Parents, especially the mothers, of children with ongoing treatment for cancer are at risk of developing PTSS. Supportive psychological interventions to attenuate the negative emotions of the parents and improve their family functions are important means to promote their natural protective mechanisms to cope with the stressful events.

Peripheral Biomarker Candidates of Posttraumatic Stress Disorder

There is high variability in the manifestation of physical and mental health problems following exposure to trauma and disaster. Although most people may show a range of acute symptoms in the aftermath of traumatic events, chronic and persistent mental disorders may not be developed in all individuals who were exposed to traumatic events. The most common long-term pathological consequence after trauma exposure is posttraumatic stress disorder (PTSD). However, comorbid conditions including depression, anxiety disorder, substance use-related problems, and a variety of other symptoms may frequently be observed in individuals with trauma exposure. Post-traumatic syndrome (PTS) is defined collectively as vast psychosocial problems that could be experienced in response to traumatic events. It is important to predict who will continue to suffer from physical and mental health problems and who will recover following trauma exposure. However, given the heterogeneity and variability in symptom manifestations, it is difficult to find identify biomarkers which predict the development of PTSD. In this review, we will summarize the results of recent studies with regard to putative biomarkers of PTSD and suggest future research directions for biomarker discovery for PTSD.

Resilience and symptom reporting following mild traumatic brain injury in military service members

PRIMARY OBJECTIVE

The purpose of this study was to examine the relationship between resilience and symptom reporting following mild traumatic brain injury (mTBI). It was hypothesized that, as resilience increases, self-reported symptoms would decrease.

RESEARCH DESIGN

Cross-sectional design.

METHODS AND PROCEDURES

Participants were 142 US military service members who sustained a mTBI, divided into three resilience groups based on participants' responses on the Response to Stressful Experiences Scale: Moderate (n = 42); High (n = 51); and Very High (n = 49). Participants completed the Neurobehavioral Symptom Inventory (NSI) and PTSD Checklist-Civilian Version (PCL-C) within 12 months following injury.

MAIN OUTCOMES AND RESULTS

There were significant main effects for the NSI total score, cognitive cluster and affective cluster, as well as for the PCL-C total score, avoidance cluster and hyperarousal cluster. Pairwise comparisons revealed that there was a negative relationship between resilience and self-reported symptoms overall. Specifically, participants with higher resilience reported fewer post-concussion and PTSD-related symptoms than participants with lower levels of resilience.

CONCLUSIONS

These findings underscore the important role that resilience plays in symptom expression in military service members with mTBI and suggest that research on targeted interventions to increase resilience in the acute phase following injury is indicated.

Relationships among Trait Resilience, Virtues, Post-traumatic Stress Disorder, and Post-traumatic Growth

The present study aims to examine the relationship between trait resilience and virtues in the context of trauma. A total of 537 participants who attended the preliminary investigation and completed the Life Events Checklist were screened. Of these participants, 142 suffered from personal traumatic experiences in the past year; these individuals were qualified and invited to respond to online questionnaires to assess trait resilience, virtues (i.e., Conscientiousness, Vitality, and Relationship), post-traumatic stress disorder (PTSD) symptoms, and post-traumatic growth (PTG). The following questionnaires were used: Connor-Davidson Resilience Scale-Revised, Chinese Virtues Questionnaire, PTSD Checklist-Specific, and Post-traumatic Growth Inventory-Chinese. Only 95 participants who manifested self-reported PTSD symptoms and PTG were involved in the current analyses. Trauma was positively and significantly correlated with PTSD in the current sample. Results indicated that trait resilience was positively associated with virtues and PTG; by contrast, PTSD scores were negatively but not significantly related to most of these factors. The three virtues contributed to PTG to a greater extent than trait resilience in non-PTSD and PTSD groups. However, trait resilience remained a significant predictor in the PTSD group even when the three virtues were controlled. The relationship between trait resilience and PTG was moderated by PTSD type (non-PTSD group vs. PTSD group). Our results further suggested that trait resilience and virtues were conceptually related but functionally different constructs. Trait resilience and virtues are positively related; thus, these factors contributed variances to PTG in the context of trauma; however, trait resilience is only manifested when virtues are controlled and when individuals are diagnosed as PTSD. Furthermore, implications and limitations of this study are discussed.

Association between virtues and posttraumatic growth: preliminary evidence from a Chinese community sample after earthquakes

Objective. Relationship, vitality, and conscientiousness are three fundamental virtues that have been recently identified as important individual differences to health, well being, and positive development. This cross-sectional study attempted to explore the relationship between the three constructs and post-traumatic growth (PTG) in three directions, including indirect trauma samples without post-traumatic stress disorder (PTSD), direct trauma samples without PTSD, and direct trauma samples with PTSD.

Methods. A total of 340 community participants from Sichuan Province, Mainland China involved in the study, most of which experienced Wenchuan and Lushan Earthquake. Participants were required to complete the self-reported questionnaire packages at one time point for obtaining their scores on virtues (Chinese Virtues Questionnaire), PTSD (PTSD Checklist-Specific), and PTG (Post-traumatic Growth Inventory-Chinese).

Results. Significant and positive correlations between the three virtues and PTG were identified (r = .39–.56; p < .01). Further regression analysis by stepwise method reveled that: in the indirect trauma samples, vitality explained 32% variance of PTG. In reference to the direct trauma sample without PTSD, both relationship and conscientiousness explained 32% variance of PTG, whereas in the direct trauma sample with PTSD, only conscientiousness accounted for 31% the variance in PTG.

Conclusion.This cross-sectional investigation partly revealed the roles of different virtues in trauma context. Findings suggest important implications for strengths-based treatment.

Blood transcriptomic markers for major depression: from animal models to clinical settings

Depression is a heterogeneous disorder and, similar to other spectrum disorders, its manifestation varies by age of onset, severity, comorbidity, treatment responsiveness, and other factors. A laboratory blood test based on specific biomarkers for major depressive disorder (MDD) and its subgroups could increase diagnostic accuracy and expedite the initiation of treatment. We identified candidate blood biomarkers by examining genome-wide expression differences in the blood of animal models representing both the genetic and environmental/stress etiologies of depression. Human orthologs of the resulting transcript panel were tested in pilot studies. Transcript abundance of 11 blood markers differentiated adolescent subjects with early-onset MDD from adolescents with no disorder (ND). A set of partly overlapping transcripts distinguished adolescent patients who had comorbid anxiety disorders from those with only MDD. In adults, blood levels of nine transcripts discerned subjects with MDD from ND controls. Even though cognitive behavioral therapy (CBT) resulted in remission of some patients, the levels of three transcripts consistently signaled prior MDD status. A coexpression network of transcripts seems to predict responsiveness to CBT. Thus, our approach can be developed into clinically valid diagnostic panels of blood transcripts for different manifestations of MDD, potentially reducing diagnostic heterogeneity and advancing individualized treatment strategies.

Searching for non-genetic molecular and imaging PTSD risk and resilience markers: Systematic review of literature and design of the German Armed Forces PTSD biomarker study

Biomarkers allowing the identification of individuals with an above average vulnerability or resilience for posttraumatic stress disorder (PTSD) would especially serve populations at high risk for trauma exposure like firefighters, police officers and combat soldiers. Aiming to identify the most promising putative PTSD vulnerability markers, we conducted the first systematic review on potential imaging and non-genetic molecular markers for PTSD risk and resilience. Following the PRISMA guidelines, we systematically screened the PubMed database for prospective longitudinal clinical studies and twin studies reporting on pre-trauma and post-trauma PTSD risk and resilience biomarkers. Using 25 different combinations of search terms, we retrieved 8151 articles of which we finally included and evaluated 9 imaging and 27 molecular studies. In addition, we briefly illustrate the design of the ongoing prospective German Armed Forces (Bundeswehr) PTSD biomarker study (Bw-BioPTSD) which not only aims to validate these previous findings but also to identify novel and clinically applicable molecular, psychological and imaging risk, resilience and disease markers for deployment-related psychopathology in a cohort of German soldiers who served in Afghanistan.

The impact of past direct-personal traumatic events on 12-month outcome in first episode psychotic mania: trauma and early psychotic mania

OBJECTIVE

Past traumatic events have been associated with poorer clinical outcomes in people with bipolar disorder. However, the impact of these events in the early stages of the illness remains unclear. The aim of this study was to investigate whether prior traumatic events were related to poorer outcomes 12 months following a first episode of psychotic mania.

METHODS

Traumatic events were retrospectively evaluated from patient files in a sample of 65 participants who had experienced first episode psychotic mania. Participants were aged between 15 and 28 years and were treated at a specialised early psychosis service. Clinical outcomes were measured by a variety of symptomatic and functioning scales at the 12-month time-point.

RESULTS

Direct-personal traumatic experiences prior to the onset of psychotic mania were reported by 48% of the sample. Participants with past direct-personal trauma had significantly higher symptoms of mania (p=0.02), depression (p=0.03) and psychopathology (p=0.01) 12 months following their first episode compared to participants without past direct-personal trauma, with medium to large effects observed. After adjusting for baseline scores, differences in global functioning (as measured by the Global Assessment of Functioning scale) were non-significant (p=0.05); however, participants with past direct-personal trauma had significantly poorer social and occupational functioning (p=0.04) at the 12-month assessment with medium effect.

CONCLUSIONS

Past direct-personal trauma may predict poorer symptomatic and functional outcomes after first episode psychotic mania. Limitations include that the findings represent individuals treated at a specialist early intervention centre for youth and the retrospective assessment of traumatic events may have been underestimated.

Altered spontaneous neuronal activity of visual cortex and medial anterior cingulate cortex in treatment-naïve posttraumatic stress disorder

BACKGROUND

Although no more traumatic stimuli exists, a variety of symptoms are persisting in chronic Posttraumatic Stress Disorder (PTSD) patients. It is therefore necessary to explore the spontaneous brain activity of treatment-naïve PTSD patients during resting-state.

METHOD

Seventeen treatment-naïve PTSD patients and twenty traumatized controls were recruited and underwent a resting functional magnetic resonance imaging (Rs-fMRI) scan. The differences of regional brain spontaneous activity between the participants with and without PTSD were measured by Amplitude of Low-frequency fluctuation (ALFF). The relationship between the altered brain measurements and the symptoms of PTSD were analyzed.

RESULT

Compared to traumatized controls, the PTSD group showed significantly altered ALFF in many emotion-related brain regions, such as the medial anterior cingulate cortex (MACC), dorsolateral prefrontal cortex (DLPFC), insular (IC), middle temporal gyrus (MTG), and ventral posterior cingulate cortex (VPCC). Interestingly this is the first report of a hyperactive visual cortex (V1/V2) during resting-state in treatment-naïve PTSD patients. There were significant positive correlations between ALFF values in the bilateral visual cortex and re-experiencing or avoidance in PTSD. Negative correlation was observed between ALFF values in MACC and avoidance.

CONCLUSION

This study suggested that the visual cortex and the MACC may be involved in the characteristic symptoms of chronic PTSD, such as re-experiencing and avoidance. Future studies that focus on these areas of the brain are required, as alteration of these areas may act as a biomarker and could be targeted in future treatments for PTSD.

Characterization of post-traumatic stress disorder using resting-state fMRI with a multi-level parametric classification approach

Functional neuroimaging studies have found intra-regional activity and inter-regional connectivity alterations in patients with post-traumatic stress disorder (PTSD). However, the results of these studies are based on group-level statistics and therefore it is unclear whether PTSD can be discriminated at single-subject level, for instance using the machine learning approach. Here, we proposed a novel framework to identify PTSD using multi-level measures derived from resting-state functional MRI (fMRI). Specifically, three levels of measures were extracted as classification features: (1) regional amplitude of low-frequency fluctuations (univariate feature), which represents local spontaneous synchronous neural activity; (2) temporal functional connectivity (bivariate feature), which represents the extent of similarity of local activity between two regions, and (3) spatial functional connectivity (multivariate feature), which represents the extent of similarity of temporal correlation maps between two regions. Our method was evaluated on 20 PTSD patients and 20 demographically matched healthy controls. The experimental results showed that the features of each level could successfully discriminate PTSD patients from healthy controls. Furthermore, the combination of multi-level features using multi-kernel learning can further improve the classification performance. Specifically, the classification accuracy obtained by the proposed framework was 92.5 %, which was an increase of at least 5 and 17.5 % from the two-level and single-level feature based methods, respectively. Particularly, the limbic structure and prefrontal cortex provided the most discriminant features for classification, consistent with results reported in previous studies. Together, this study demonstrated for the first time that patients with PTSD can be identified at the individual level using resting-state fMRI data. The promising classification results indicated that this method may provide a complementary approach for improving the clinical diagnosis of PTSD.

Theta frequency activity during rapid eye movement (REM) sleep is greater in people with resilience versus PTSD

Emotional memory consolidation has been associated with rapid eye movement (REM) sleep, and recent evidence suggests that increased electroencephalogram spectral power in the theta (4-8 Hz) frequency range indexes this activity. REM sleep has been implicated in posttraumatic stress disorder (PTSD) as well as in emotional adaption. In this cross-sectional study, thirty young healthy African American adults with trauma exposure were assessed for PTSD status using the Clinician Administered PTSD Scale. Two consecutive night polysomnographic (PSG) recordings were performed and data scored for sleep stages. Quantitative electroencephalographic spectral analysis was used to measure theta frequency components sampled from REM sleep periods of the second-night PSG recordings. Our objective was to compare relative theta power between trauma-exposed participants who were either resilient or had developed PTSD. Results indicated higher right prefrontal theta power during the first and last REM periods in resilient participants compared with participants with PTSD. Right hemisphere prefrontal theta power during REM sleep may serve as a biomarker of the capacity for adaptive emotional memory processing among trauma-exposed individuals.

Quantitative prediction of individual psychopathology in trauma survivors using resting-state FMRI

Neuroimaging techniques hold the promise that they may one day aid the clinical assessment of individual psychiatric patients. However, the vast majority of studies published so far have been based on average differences between groups. This study employed a multivariate approach to examine the potential of resting-state functional magnetic resonance imaging (MRI) data for making accurate predictions about psychopathology in survivors of the 2008 Sichuan earthquake at an individual level. Resting-state functional MRI data was acquired for 121 survivors of the 2008 Sichuan earthquake each of whom was assessed for symptoms of post-traumatic stress disorder (PTSD) using the 17-item PTSD Checklist (PCL). Using a multivariate analytical method known as relevance vector regression (RVR), we examined the relationship between resting-state functional MRI data and symptom scores. We found that the use of RVR allowed quantitative prediction of clinical scores with statistically significant accuracy (correlation=0.32, P=0.006; mean squared error=176.88, P=0.001). Accurate prediction was based on functional activation in a number of prefrontal, parietal, and occipital regions. This is the first evidence that neuroimaging techniques may inform the clinical assessment of trauma-exposed individuals by providing an accurate and objective quantitative estimation of psychopathology. Furthermore, the significant contribution of parietal and occipital regions to such estimation challenges the traditional view of PTSD as a disorder specific to the fronto-limbic network.

Using structural neuroanatomy to identify trauma survivors with and without post-traumatic stress disorder at the individual level

BACKGROUND

At present there are no objective, biological markers that can be used to reliably identify individuals with post-traumatic stress disorder (PTSD). This study assessed the diagnostic potential of structural magnetic resonance imaging (sMRI) for identifying trauma-exposed individuals with and without PTSD.

METHOD

sMRI scans were acquired from 50 survivors of the Sichuan earthquake of 2008 who had developed PTSD, 50 survivors who had not developed PTSD and 40 healthy controls who had not been exposed to the earthquake. Support vector machine (SVM), a multivariate pattern recognition technique, was used to develop an algorithm that distinguished between the three groups at an individual level. The accuracy of the algorithm and its statistical significance were estimated using leave-one-out cross-validation and permutation testing.

RESULTS

When survivors with PTSD were compared against healthy controls, both grey and white matter allowed discrimination with an accuracy of 91% (p < 0.001). When survivors without PTSD were compared against healthy controls, the two groups could be discriminated with accuracies of 76% (p < 0.001) and 85% (p < 0.001) based on grey and white matter, respectively. Finally, when survivors with and without PTSD were compared directly, grey matter allowed discrimination with an accuracy of 67% (p < 0.001); in contrast the two groups could not be distinguished based on white matter.

CONCLUSIONS

These results reveal patterns of neuroanatomical alterations that could be used to inform the identification of trauma survivors with and without PTSD at the individual level, and provide preliminary support to the development of SVM as a clinically useful diagnostic aid.

Resilience definitions, theory, and challenges: interdisciplinary perspectives

In this paper, inspired by the plenary panel at the 2013 meeting of the International Society for Traumatic Stress Studies, Dr. Steven Southwick (chair) and multidisciplinary panelists Drs. George Bonanno, Ann Masten, Catherine Panter-Brick, and Rachel Yehuda tackle some of the most pressing current questions in the field of resilience research including: (1) how do we define resilience, (2) what are the most important determinants of resilience, (3) how are new technologies informing the science of resilience, and (4) what are the most effective ways to enhance resilience? These multidisciplinary experts provide insight into these difficult questions, and although each of the panelists had a slightly different definition of resilience, most of the proposed definitions included a concept of healthy, adaptive, or integrated positive functioning over the passage of time in the aftermath of adversity. The panelists agreed that resilience is a complex construct and it may be defined differently in the context of individuals, families, organizations, societies, and cultures. With regard to the determinants of resilience, there was a consensus that the empirical study of this construct needs to be approached from a multiple level of analysis perspective that includes genetic, epigenetic, developmental, demographic, cultural, economic, and social variables. The empirical study of determinates of resilience will inform efforts made at fostering resilience, with the recognition that resilience may be enhanced on numerous levels (e.g., individual, family, community, culture).

CSF 5-HIAA, cortisol and DHEAS levels in suicide attempters

The serotonin system and the hypothalamic-pituitary-adrenal (HPA) axis are involved in the biological vulnerability to suicidal behaviour. Altered levels of dehydroepiandrosterone (DHEA) and its sulphate ester DHEAS have been reported in neuropsychiatric conditions. The aim of this study was to investigate CSF levels of 5-Hydroxyindoleacetic acid (5-HIAA) and CSF and plasma levels of cortisol and DHEAS in 28 medication free suicide attempters and 19 healthy volunteers. Another aim was to investigate the relationship between neuroendocrine measures and childhood trauma in suicide attempters. As the study design includes a longitudinal part, we investigated whether CSF cortisol, 5-HIAA or DHEAS would predict subsequent suicide. We hypothesized higher cortisol levels in suicide attempters and lower CSF 5-HIAA levels and higher cortisol levels in suicide victims. Suicide attempters had higher CSF and plasma cortisol levels compared to healthy volunteers. Male suicide attempters had higher CSF DHEAS levels and female suicide attempters had lower CSF 5-HIAA levels compared to male and female healthy volunteers respectively. Exposure to interpersonal violence as a child showed a negative correlation with CSF cortisol/DHEAS ratio adjusted for age, gender and depression severity in a regression analysis. Suicide victims tended to have low CSF 5-HIAA and high CSF cortisol. Abused suicide victims had higher CSF cortisol compared to suicide victims with low exposure to interpersonal violence as a child. The results underlie the important role of the serotonergic system and HPA axis in suicidal behaviour and suggest that CSF DHEAS may be elevated in male suicide attempters.

Translational reciprocity: bridging the gap between preclinical studies and clinical treatment of stress effects on the adolescent brain

The genetic, biological, and environmental backgrounds of an organism fundamentally influence the balance between risk and resilience to stress. Sex, age, and environment transact with responses to trauma in ways that can mitigate or exacerbate the likelihood that post-traumatic stress disorder will develop. Translational approaches to modeling affective disorders in animals will ultimately provide novel treatments and a better understanding of the neurobiological underpinnings behind these debilitating disorders. The extant literature on trauma/stress has focused predominately on limbic and cortical structures that innervate the hypothalamic-pituitary-adrenal axis and influence glucocorticoid-mediated negative feedback. It is through these neuroendocrine pathways that a self-perpetuating fear memory can propagate the long-term effects of early life trauma. Recent work incorporating translational approaches has provided novel pathways that can be influenced by early life stress, such as the glucocorticoid receptor chaperones, including FKBP51. Animal models of stress have differing effects on behavior and endocrine pathways; however, complete models replicating clinical characteristics of risk and resilience have not been rigorously studied. This review discusses a four-factor model that considers the importance of studying both risk and resilience in understanding the developmental response to trauma/stress. Consideration of the multifactorial nature of clinical populations in the design of preclinical models and the application of preclinical findings to clinical treatment approaches comprise the core of translational reciprocity, which is discussed in the context of the four-factor model.

The use of biomarkers in the military: from theory to practice

This paper provides a summary of relevant issues covered in the conference, "The Use of Biomarkers in the Military: Theory to Practice" held at the New York Academy of Science on September 14, 2012. The conference covered the state of the science in identification of PTSD biomarkers, including, the definition of different classes of biomarkers pertaining to PTSD. The aim of the satellite conference was to bring together researchers who have been supported by the Department of Defense, Veterans Administration, National Institutes of Health, and other agencies around the world, who are interested in the identification of biomarkers for PTSD risk, diagnosis, symptom severity and treatment response, for a discussion of salient issues regarding biomarker development for PTSD, as well as special considerations for the use of biomarkers in the military.

Predictors of susceptibility and resilience in an animal model of posttraumatic stress disorder

Animal models of posttraumatic stress disorder (PTSD) are based on fear conditioning where innocuous cues elicit reactions that originally occur to traumatic events--a core feature of PTSD. Another core feature is hyperarousal--exaggerated reactions to stressful events. One limitation of animal models of PTSD is that group effects do not model the sporadic incidence of PTSD. We developed an animal model of PTSD in which rabbit nictitating membrane responses become exaggerated as a function of classical conditioning to a tone conditioned stimulus (CS) paired with a shock unconditioned stimulus (US). Exaggerated responses to the US are a form of hyperarousal termed conditioning-specific reflex modification (CRM) and occur in the absence of the CS. Inspecting data across several experiments, we determined 25% of our rabbits exhibit strong CRM despite all subjects having high levels of conditioning. To determine how prone rabbits were to CRM (susceptibility) or how resistant (resilience), we examined data from 135 rabbits analyzing for factors during CS-US pairings and during US prescreening that would predict CRM. We found the magnitude of CRM was correlated with the onset latency and area of conditioned responding during CS-US pairings and with the peak latency of a response during US pretesting. In an animal model of PTSD that more accurately reflects clinical prevalence, we can begin to predict susceptibility not only during responding to a stressful conditioning situation but also during a screening process before the stressful situation takes place. The results suggest relatively innocuous testing may help detect PTSD after trauma and screen for it before trauma occurs.

Prognostic and symptomatic aspects of rapid eye movement sleep in a mouse model of posttraumatic stress disorder

Not every individual develops Posttraumatic Stress Disorder (PTSD) after the exposure to a potentially traumatic event. Therefore, the identification of pre-existing risk factors and early diagnostic biomarkers is of high medical relevance. However, no objective biomarker has yet progressed into clinical practice. Sleep disturbances represent commonly reported complaints in PTSD patients. In particular, changes in rapid eye movement sleep (REMS) properties are frequently observed in PTSD patients. Here, we examined in a mouse model of PTSD whether (1) mice developed REMS alterations after trauma and (2) whether REMS architecture before and/or shortly after trauma predicted the development of PTSD-like symptoms. We monitored sleep-wake behavior via combined electroencephalogram/electromyogram recordings immediately before (24 h pre), immediately after (0-48 h post) and 2 months after exposure to an electric foot shock in male C57BL/6N mice (n = 15). PTSD-like symptoms, including hyperarousal, contextual, and generalized fear, were assessed 1 month post-trauma. Shocked mice showed early onset and sustained elevation of REMS compared to non-shocked controls. In addition, REMS architecture before trauma was correlated with the intensity of acoustic startle responses, but not contextual fear, 1 month after trauma. Our data suggest REMS as prognostic (pre-trauma) and symptomatic (post-trauma) marker of PTSD-like symptoms in mice. Translated to the situation in humans, REMS may constitute a viable, objective, and non-invasive biomarker in PTSD and other trauma-related psychiatric disorders, which could guide pharmacological interventions in humans at high risk.

Psychosocial animal model of PTSD produces a long-lasting traumatic memory, an increase in general anxiety and PTSD-like glucocorticoid abnormalities

Post-traumatic stress disorder (PTSD) is characterized by a pathologically intense memory for a traumatic experience, persistent anxiety and physiological abnormalities, such as low baseline glucocorticoid levels and increased sensitivity to dexamethasone. We have addressed the hypothesis that rats subjected to chronic psychosocial stress would exhibit PTSD-like sequelae, including traumatic memory expression, increased anxiety and abnormal glucocorticoid responses. Adult male Sprague-Dawley rats were exposed to a cat on two occasions separated by 10 days, in conjunction with chronic social instability. Three weeks after the second cat exposure, the rats were tested for glucocorticoid abnormalities, general anxiety and their fear-conditioned memory of the two cat exposures. Stressed rats exhibited reduced basal glucocorticoid levels, increased glucocorticoid suppression following dexamethasone administration, heightened anxiety and a robust fear memory in response to cues that were paired with the two cat exposures. The commonalities in endocrine and behavioral measures between psychosocially stressed rats and traumatized people with PTSD provide the opportunity to explore mechanisms underlying psychological trauma-induced changes in neuroendocrine systems and cognition.