Effects of traumatic stress on brain structure and function: relevance to early responses to trauma

Differential Response to Three Antidepressants in Patients with Major Depressive Episode Who Suffered Covid-19-Related Trauma

BACKGROUND

The Covid 19 pandemic might have impacted response to drug treatment in major depressive episode (MDE). We compared responses to three different antidepressant drugs, i.e., vortioxetine, sertraline, and trazodone, in outpatients with MDE during Major Depressive Disorder (MDD), Bipolar Disorder (BD), or schizophrenia and related psychoses (SSOPDs) during two time periods, i.e., before and after suffering Covid-19-related trauma.

METHODS

We conducted an observational study on clinically stabilised for at least 6 months outpatients with MDE during the course of MDD (N=58), BD (N=33), or SSOPDs (N=51). Patients, whose baseline assessments of Montgomery-Åsberg Rating Scale (MADRS), Hamilton Anxiety Rating Scale (Ham-A), Brief Psychiatric Rating Scale (BPRS), Visual Analogue Scale for Craving (VAS-crav) and World Health Organization Quality of Life, Brief version (WHOQOL-BREF) were available, were recruited at the time they suffered Covid-19-related traumas. Fifty patients, prior to the pandemic, when they were clinically stable, were treated with 15 mg/die vortioxetine, 44 with 450 mg/die trazodone, and 48 with 150 mg/die sertraline. After experiencing a major Covid-19-related personal trauma, patients showed clinical worsening which required dosage adjustment (20 mg/day vortioxetine; 600 mg/day trazodone, and 200 mg/day sertraline) and, for some of them, hospitalisation. Scores on the MADRS, Ham-A, BPRS, VAS-crav and WHOQOL-BREF were compared drug-wise and genderwise with Student's t test for continuous variables and Χ2 for categorical variables.

RESULTS

The sample consisted of 142 outpatients (age, mean 39.63 ± 16.84; 70 men and 72 women); women were older than men (mean age 43.18 ± 17.61 vs. 35.98 ± 15.30; p=0.01). The two genders did not differ on other variables. For all treatments, worsening symptoms were observed at the time of trauma, followed by slow recovery with treatment readjustment. Trauma-related worsening in patients on vortioxetine was less intense than patients on the other two antidepressants and recovery was faster. All drugs were associated with an improvement in QoL. The vortioxetine group showed a lower hospitalisation rate (24%) than sertraline (35.4%) and trazodone (38.6%), but this was not significant (p=0.27).

CONCLUSION

All drugs improved symptoms of Covid-19 trauma in patients with MDE, with vortioxetine showing a small advantage. No differences between vortioxetine, sertraline and trazodone were found as concerning the need for hospitalisation.

Hippocampal Resting-State Functional Connectivity Forecasts Individual Posttraumatic Stress Disorder Symptoms: A Data-Driven Approach

BACKGROUND

Posttraumatic stress disorder (PTSD) is a debilitating disorder, and there is no current accurate prediction of who develops it after trauma. Neurobiologically, individuals with chronic PTSD exhibit aberrant resting-state functional connectivity (rsFC) between the hippocampus and other brain regions (e.g., amygdala, prefrontal cortex, posterior cingulate), and these aberrations correlate with severity of illness. Previous small-scale research (n < 25) has also shown that hippocampal rsFC measured acutely after trauma is predictive of future severity using a region-of-interest-based approach. While this is a promising biomarker, to date, no study has used a data-driven approach to test whole-brain hippocampal FC patterns in forecasting the development of PTSD symptoms.

METHODS

A total of 98 adults at risk of PTSD were recruited from the emergency department after traumatic injury and completed resting-state functional magnetic resonance imaging (8 min) within 1 month; 6 months later, they completed the Clinician-Administered PTSD Scale for DSM-5 for assessment of PTSD symptom severity. Whole-brain rsFC values with bilateral hippocampi were extracted (using CONN) and used in a machine learning kernel ridge regression analysis (PRoNTo); a k-folds (k = 10) and 70/30 testing versus training split approach were used for cross-validation (1000 iterations to bootstrap confidence intervals for significance values).

RESULTS

Acute hippocampal rsFC significantly predicted Clinician-Administered PTSD Scale for DSM-5 scores at 6 months (r = 0.30, p = .006; mean squared error = 120.58, p = .006; R² = 0.09, p = .025). In post hoc analyses, hippocampal rsFC remained significant after controlling for demographics, PTSD symptoms at baseline, and depression, anxiety, and stress severity at 6 months (B = 0.59, SE = 0.20, p = .003).

CONCLUSIONS

Findings suggest that functional connectivity of the hippocampus across the brain acutely after traumatic injury is associated with prospective PTSD symptom severity.

Whole-brain morphometry in Canadian soldiers with posttraumatic stress disorder

Patients with posttraumatic stress disorder (PTSD) display several structural brain differences when compared with healthy individuals. However, findings are particularly inconsistent for soldiers with PTSD. Here, we characterized the brain morphometry of 37 soldiers from the Canadian Armed Forces with adulthood war-related PTSD using structural magnetic resonance imaging. We assessed time since trauma, as well as PTSD, depressive, and anxiety symptoms with the Modified PTSD Symptoms Scale, Beck Depression Inventory, and Beck Anxiety Inventory, respectively. Whole-brain morphometry was extracted with FreeSurfer and compared with a validated normative database of more than 2700 healthy individuals. Volume and thickness from several regions differed from the norms. Frontal regions were smaller and thinner, particularly the superior and rostral middle frontal gyri. Furthermore, smaller left rostral middle frontal gyrus, left pericalcarine cortex, and right fusiform gyrus were associated with more recent trauma. All subcortical structures were bigger, except the hippocampus. These findings suggest a particular brain morphometric signature of PTSD in soldiers. Smaller and thinner frontal and larger subcortical regions support impaired top-down and/or downregulation of emotional response in PTSD. Finally, the correlation of smaller frontal, temporal, and occipital regions with more recent trauma might inform future therapeutic approaches.

Acute White Matter Integrity Post-trauma and Prospective Posttraumatic Stress Disorder Symptoms

Background: Little is known about what distinguishes those who are resilient after trauma from those at risk for developing posttraumatic stress disorder (PTSD). Previous work indicates white matter integrity may be a useful biomarker in predicting PTSD. Research has shown changes in the integrity of three white matter tracts-the cingulum bundle, corpus callosum (CC), and uncinate fasciculus (UNC)-in the aftermath of trauma relate to PTSD symptoms. However, few have examined the predictive utility of white matter integrity in the acute aftermath of trauma to predict prospective PTSD symptom severity in a mixed traumatic injury sample. Method: Thus, the current study investigated acute brain structural integrity in 148 individuals being treated for traumatic injuries in the Emergency Department of a Level 1 trauma center. Participants underwent diffusion-weighted magnetic resonance imaging 2 weeks post-trauma and completed several self-report measures at 2-weeks (T1) and 6 months (T2), including the Clinician Administered PTSD Scale for DSM-V (CAPS-5), post-injury. Results: Consistent with previous work, T1 lesser anterior cingulum fractional anisotropy (FA) was marginally related to greater T2 total PTSD symptoms. No other white matter tracts were related to PTSD symptoms. Conclusions: Results demonstrate that in a traumatically injured sample with predominantly subclinical PTSD symptoms at T2, acute white matter integrity after trauma is not robustly related to the development of chronic PTSD symptoms. These findings suggest the timing of evaluating white matter integrity and PTSD is important as white matter differences may not be apparent in the acute period after injury.

Paternal adverse childhood experiences: Associations with infant DNA methylation

Adverse childhood experiences (ACEs), or cumulative childhood stress exposures, such as abuse, neglect, and household dysfunction, predict later health problems in both the exposed individuals and their offspring. One potential explanation suggests exposure to early adversity predicts epigenetic modification, especially DNA methylation (DNAm), linked to later health. Stress experienced preconception by mothers may associate with DNAm in the next generation. We hypothesized that fathers' exposure to ACEs also associates with their offspring DNAm, which, to our knowledge, has not been previously explored. An epigenome-wide association study (EWAS) of blood DNAm (n = 45) from 3-month-old infants was regressed onto fathers' retrospective ACEs at multiple Cytosine-phosphate-Guanosine (CpG) sites to discover associations. This accounted for infants' sex, age, ethnicity, cell type proportion, and genetic variability. Higher ACE scores associated with methylation values at eight CpGs. Post-hoc analysis found no contribution of paternal education, income, marital status, and parental postpartum depression, but did with paternal smoking and BMI along with infant sleep latency. These same CpGs also contributed to the association between paternal ACEs and offspring attention problems at 3 years. Collectively, these findings suggested there were biological associations with paternal early life adversity and offspring DNAm in infancy, potentially affecting offspring later childhood outcomes.

EMDR as an Adjunctive Psychological Therapy for Patients With Functional Neurological Disorder: Illustrative Case Examples

Functional neurological disorder (FND) is a common diagnosis in neurology clinics, and there is some evidence psychological therapy can be of benefit. Eye movement desensitization and reprocessing therapy (EMDR) is a well-evidenced treatment for posttraumatic stress disorder (PTSD), and there is increasing evidence that it is beneficial for other conditions. EMDR is a therapy designed to focus on distressing memories, and therefore can be used for non-PTSD presentations where distressing memories are relevant. There is a small amount of case study evidence that EMDR can be used successfully with FND presentations and comorbid PTSD. This article describes two illustrative case examples of people diagnosed with FND who have distressing memories relevant to their presentation. Presenting functional symptoms included functional non-epileptic attacks and functional sensory symptoms. Psychological treatment-as-usual plus EMDR resulted in improvements for both cases and demonstrated that EMDR is a promising additional treatment option for FND presentations, appropriately selected. Recommendations regarding further research are made.

Autonomic and cortical response of soldiers in different combat scenarios

INTRODUCTION

The study of chronic and acute responses when exposed to extreme, aggressive and stressful environments, such as in combat environments, is becoming increasingly popular as such information leads to better optimisation of soldiers' physical and psychological performance, as well as mission effectiveness and efficiency. Due to internal complexity, uncertainty and variability of real combat scenarios, a specific approach to all possible types of military combat scenarios is necessary.

METHODS

Modifications in the autonomic modulation and cortical arousal before and after asymmetrical, symmetrical and close quarter combat simulations were analysed in 31 male professional veteran soldiers (age: 34.5±4.2 years) with between seven and 18 years of experience in their respective units, as well as experience in international missions in current conflict areas such as Lebanon, Afghanistan, Bosnia, Kosovo and Iraq.

RESULTS

The three combat situations produced a non-significant decrease in cortical arousal after combat simulations, presenting a trivial effect size in symmetrical and close quarter combat situations and a small effect size in asymmetrical situations. HR increased significantly in the three combat situations, and close quarter combat produced the highest sympathetic modulation of the three situations analysed.

CONCLUSION

Symmetrical, asymmetrical and close quarter combat situations produced an increase in sympathetic modulation, being highest in the close quarter combat situation, where actions are performed at a close distance and in closed spaces.

Biopsychosocial outcome indicators in traumatic brain injuries

BACKGROUND

Traumatic brain injury (TBI) remains a silent and global epidemic which creates an aftermath of convoluted dynamics. Despite significant incidence rates and increasing awareness over the long-term catastrophic implications, there remain marked contrasts between acute vs. post-acute rehabilitation processes in the United States.

OBJECTIVE

To explore existing research and highlight the complexity of TBIs to inform vital changes needed to reduce the significant differences and inconsistencies across post-acute treatment settings. To highlight how psychologists/neuropsychologists and other rehabilitation professionals maintain a prominent operational presence in post-acute settings resulting in key leadership opportunities to support a more efficient longitudinal continuation of care model.

METHODS

Literature search of various health science databases was completed for articles between 1987 to 2019 to explore the range and depth of post-acute treatment, model, and outcomes research.

RESULTS

Despite progressive medical advancements, translation of relevant rehabilitation research and practices into post-acute treatment settings remains inconsistent.

CONCLUSIONS

Significant barriers remain for objective and comprehensive evaluation(s) of post-acute program quality and purported patient outcomes in the United States. There remains a lack of consensually relevant and objective metrics. Further investigation is recommended for: consensus on longitudinal post-acute brain injury outcome measures; functional relevance of program accreditations/certifications; outcome differences based on team composition and program resources; and patient/stakeholder variables/input to support optimal post-acute service access and delivery.

Serotonergic control of GABAergic inhibition in the lateral amygdala

Much evidence implicates the serotonergic regulation of the amygdala in anxiety. Thus the present study was undertaken to characterize the influence of serotonin (5-HT) on principal neurons (PNs) of the rat lateral amygdala (LA), using whole cell recordings in vitro. Because inhibition is a major determinant of PN activity, we focused on the control of GABAergic transmission by 5-HT. IPSCs were elicited by local electrical stimulation of LA in the presence of glutamate receptor antagonists. We found that 5-HT reduces GABA_A inhibitory postsynaptic currents (IPSCs) via presynaptic 5-HT_1B receptors. While the presynaptic inhibition of GABA release also attenuated GABA_B currents, this effect was less pronounced than for GABA_A currents because 5-HT also induced a competing postsynaptic enhancement of GABA_B currents. That is, GABA_B currents elicited by pressure application of GABA or baclofen were enhanced by 5-HT. In addition, we obtained evidence suggesting that 5-HT differentially regulates distinct subsets of GABAergic synapses. Indeed, GABA_A IPSCs were comprised of two components: a relatively 5-HT-insensitive IPSC that had a fast time course and a 5-HT-sensitive component that had a slower time course. Because the relative contribution of these two components varied depending on whether neurons were recorded at proximity versus at a distance from the stimulating electrodes, we speculate that distinct subtypes of local-circuit cells contribute the two contingents of GABAergic synapses. Overall, our results indicate that 5-HT is a potent regulator of synaptic inhibition in LA.NEW & NOTEWORTHY We report that 5-HT, acting via presynaptic 5-HT_1B receptors, attenuates GABA_A IPSCs by reducing GABA release in the lateral amygdala (LA). In parallel, 5-HT enhances GABA_B currents postsynaptically, such that GABA_B inhibitory postsynaptic currents (IPSCs) are relatively preserved from the presynaptic inhibition of GABA release. We also found that the time course of 5-HT-sensitive and -insensitive GABA_A IPSCs differ. Together, these results indicate that 5-HT is a potent regulator of synaptic inhibition in LA.

Neurobiological mechanisms underlying sex-related differences in stress-related disorders: Effects of neuroactive steroids on the hippocampus

Men and women differ in their vulnerability to a variety of stress-related illnesses, but the underlying neurobiological mechanisms are not well understood. This is likely due to a comparative dearth of neurobiological studies that assess male and female rodents at the same time, while human neuroimaging studies often don't model sex as a variable of interest. These sex differences are often attributed to the actions of sex hormones, i.e. estrogens, progestogens and androgens. In this review, we summarize the results on sex hormone actions in the hippocampus and seek to bridge the gap between animal models and findings in humans. However, while effects of sex hormones on the hippocampus are largely consistent in animals and humans, methodological differences challenge the comparability of animal and human studies on stress effects. We summarise our current understanding of the neurobiological mechanisms that underlie sex-related differences in behavior and discuss implications for stress-related illnesses.

Early childhood trauma alters neurological responses to mental stress in patients with coronary artery disease

BACKGROUND

Early childhood trauma is known to independently increase adverse outcome risk in coronary artery disease (CAD) patients, although the neurological correlates are not well understood. The purpose of this study was to examine whether early childhood trauma alters neural responses to acute mental stress in CAD patients.

METHODS

Participants (n = 152) with CAD underwent brain imaging with High Resolution Positron Emission Tomography and radiolabeled water during control (verbal counting, neutral speaking) and mental stress (mental arithmetic, public speaking). Traumatic events in childhood were assessed with the Early Trauma Inventory (ETI-SR-SF) and participants were separated by presence (ETI+) or absence (ETI-) of early childhood trauma. Brain activity during mental stress was compared between ETI+ and ETI-.

RESULTS

Compared to ETI-, ETI+ experienced greater (p < 0.005) activations during mental stress within the left anterior cingulate, bilateral frontal lobe and deactivations (p < 0.005) within the left insula, left parahippocampal gyrus, right dorsal anterior cingulate, bilateral cerebellum, bilateral fusiform gyrus, left inferior temporal gyrus, and right parietal lobe. Significant (p < 0.005) positive correlations between brain activation and ETI-SR-SF scores were observed within the left hippocampus, bilateral frontal lobe, left occipital cuneus, and bilateral temporal lobe.

LIMITATIONS

Results in non-CAD samples may differ and ETI may be subject to recall bias.

CONCLUSION

Early childhood trauma exacerbated activations in stress-responsive limbic and cognitive brain areas with direct and indirect connections to the heart, potentially contributing to adverse outcomes in CAD patients.

Amygdala growth from youth to adulthood in the macaque monkey

Emerging evidence suggests that the human amygdala undergoes extensive growth through adolescence, coinciding with the acquisition of complex socioemotional learning. Our objective was to longitudinally map volumetric growth of the nonhuman primate amygdala in a controlled, naturalistic social environment from birth to adulthood. Magnetic resonance images were collected at five time-points in 24 male and female rhesus macaques from 6 months to adulthood at 5 years. We then compared amygdala growth to other brain regions, including newly collected isocortical gray and white matter volumes, and previously published data on the same cohort. We found that amygdala volume increases by nearly 50% from age 6 months to 5 years. This dramatic growth is in contrast to overall brain and hippocampal volume, which peak near 3 years, white matter, which slows from 3 to 5 years, and isocortical gray, which has a net decrease. Similar to isocortical gray and hippocampal volumes, amygdala volume is ~8% larger in males than females. Rate of growth does not differ by sex. Although the underlying neurobiological substrate for protracted amygdala growth into adulthood is unclear, we propose it may be due in part to the unique cellular development of immature neurons in paralaminar nucleus that mature in size and connectivity with age. Prolonged amygdala maturation raises the possibility that environmental and genetic perturbations that disrupt this trajectory may contribute to the emergence of psychiatric disorders, such as anxiety, depression, schizophrenia, and autism; all in which the amygdala is strongly implicated.

Heritable Differences in Catecholamine Signaling Modulate Susceptibility to Trauma and Response to Methylphenidate Treatment: Relevance for PTSD

Alterations in cortical catecholamine signaling pathways can modulate acute and enduring responses to trauma. Heritable variation in catecholamine signaling is produced by a common functional polymorphism in the catechol-O-methyltransferase (COMT), with Val carriers exhibiting greater degradation of catecholamines than Met carriers. Furthermore, it has recently been suggested that drugs enhancing cortical catecholamine signaling may be a new therapeutic approach for posttraumatic stress disorder (PTSD) patients. We hypothesized that heritable differences in catecholamine signaling regulate the behavioral response to trauma, and that methylphenidate (MPD), a drug that preferentially blocks catecholamine reuptake in the prefrontal cortex (PFC), exerts COMT-dependent effects on trauma-induced behaviors. We first examined the contribution of the functional mutation COMTval158met to modulate enduring behavioral responses to predator stress in a unique "humanized" COMTval158met mouse line. Animals were exposed to a predator (cat) for 10 min and enduring avoidance behaviors were examined in the open field, light-dark box, and "trauma-reminder" tests 1-2 weeks later. Second, we examined the efficacy of chronic methylphenidate to reverse predator stress effects and if these effects were modulated by COMTval158met genotype. Mice were exposed to predator stress and began treatment with either saline or methylphenidate (3 mg/kg/day) 1 week after stress until the end of the testing [avoidance behaviors, working memory, and social preference (SP)]. In males, predator stress and COMTval158met had an additive effect on enduring anxiety-like behavior, with Val stressed mice showing the strongest avoidance behavior after stress compared to Met carriers. No effect of COMT genotype was observed in females. Therefore methylphenidate effects were investigated only in males. Chronic methylphenidate treatment reversed the stress-induced avoidance behavior and increased social investigation independently of genotype. Methylphenidate effects on working memory, however, were genotype-dependent, decreasing working memory in non-stressed Met carriers, and improving stress-induced working memory deficit in Val carriers. These results suggest that heritable variance in catecholamine signaling modulates the avoidance response to an acute trauma. This work supports recent human findings that methylphenidate might be a therapeutic alternative for PTSD patients and suggests that methylphenidate effects on anxiety (generalized avoidance, social withdrawal) vs. cognitive (working memory) symptoms may be modulated through COMT-independent and dependent mechanisms, respectively.

Postpartum Depressive Disorder - Psychosomatic Aspects

Postpartum depression (PPD) is the most common mental illness in mothers following the birth of a child. Since the symptoms of PPD are similar to the normal stress of healthy women following childbirth, it is often difficult for the attending gynaecologist or midwife to diagnose this illness in a timely manner and thus initiate adequate treatment and comprehensive support for the patient. Even if there are options for a screening using evaluated questionnaires and subsequent psychotherapy and/or drug therapy in the treatment of PPD which has proven effective, it is seen that, in most treatment approaches, little consideration is given to the affect-controlled interaction and the bonding behaviour between mother and child. This article presents diagnostic measures and current therapeutic approaches as well as their integration in practice in order to achieve awareness of this topic in everyday clinical practice and show the pathways of appropriate treatment. Specific multiprofessional treatment approaches which centre on the mother-child relationship demonstrate successes with regard to depression in the mothers and also on the development of a secure mother-child bond and are thus a protective factor in the development of the affected children. The now well-known effects of PPD on the fathers as well as the negative impacts of paternal depression on child development make it clear that the treatment should not focus solely on maternal depression, but also always on the family bond between the mother, child and father in the treatment.

Structural brain differences predict early traumatic memory processing

Intrusive memories are a key symptom of post-traumatic stress disorder (PTSD). They emerge early after trauma exposure and are predictive for PTSD development. There is a high relevance in evaluating the neurobiological mechanisms of early stages of intrusive symptom development to provide a further understanding of PTSD. In the present study, we explore structural differences in healthy young female subjects preceding experimental trauma exposure and their relationship to early intrusive memory development using a traumatic film paradigm. With voxel-based morphometry, we demonstrate that smaller insular volume was associated with an increased number of early intrusive film memories. Moreover, larger lingual gyrus/cerebellar and inferior frontal gyrus/precentral gyrus volumes were also related to an increased number of early intrusive film memories. Our results identify unique brain areas associated with early experimental trauma memory processing and highlight the necessity of evaluating early symptom stages relevant for personalized PTSD prevention and treatment.

Effect of acute alarm odor exposure and biological sex on generalized avoidance and glutamatergic signaling in the hippocampus of Wistar rats

Post-traumatic stress disorder (PTSD) is characterized by the development of paradoxical memory disturbances including intrusive memories and amnesia for specific details of the traumatic experience. Despite evidence that women are at higher risk to develop PTSD, most animal research has focused on the processes by which male rodents develop adaptive fear memory. As such, the mechanisms contributing to sex differences in the development of PTSD-like memory disturbances are poorly understood. In this investigation, we exposed adult male and female Wistar rats to the synthetic alarm odor 2,4,5-trimethylthiazole (TMT) to assess development of generalized fear behavior and rapid modulation of glutamate uptake and signaling cascades associated with hippocampus-dependent long-term memory. We report that female Wistar rats exposed to alarm odor exhibit context discrimination impairments relative to TMT-exposed male rats, suggesting the intriguing possibility that females are at greater risk in developing generalized fear memories. Mechanistically, alarm odor exposure rapidly modulated signaling cascades consistent with activation of the CREB shut-off cascade in the male, but not the female hippocampus. Moreover, TMT exposure dampened glutamate uptake and affected expression of the glutamate transporter, GLT-1 in the hippocampus. Taken together, these results provide evidence for rapid sex-dependent modulation of CREB signaling in the hippocampus by alarm odor exposure which may contribute to the development of generalized fear.

Current Status of Animal Models of Posttraumatic Stress Disorder: Behavioral and Biological Phenotypes, and Future Challenges in Improving Translation

Increasing predictability of animal models of posttraumatic stress disorder (PTSD) has required active collaboration between clinical and preclinical scientists. Modeling PTSD is challenging, as it is a heterogeneous disorder with ≥20 symptoms. Clinical research increasingly utilizes objective biological measures (e.g., imaging, peripheral biomarkers) or nonverbal behaviors and/or physiological responses to complement verbally reported symptoms. This shift toward more-objectively measurable phenotypes enables refinement of current animal models of PTSD, and it supports the incorporation of homologous measures across species. We reviewed >600 articles to examine the ability of current rodent models to probe biological phenotypes of PTSD (e.g., sleep disturbances, hippocampal and fear-circuit dysfunction, inflammation, glucocorticoid receptor hypersensitivity) in addition to behavioral phenotypes. Most models reliably produced enduring generalized anxiety-like or depression-like behaviors, as well as hyperactive fear circuits, glucocorticoid receptor hypersensitivity, and response to long-term selective serotonin reuptake inhibitors. Although a few paradigms probed fear conditioning/extinction or utilized peripheral immune, sleep, and noninvasive imaging measures, we argue that these should be incorporated more to enhance translation. Data on female subjects, on subjects at different ages across the life span, or on temporal trajectories of phenotypes after stress that can inform model validity and treatment study design are needed. Overall, preclinical (and clinical) PTSD researchers are increasingly incorporating homologous biological measures to assess markers of risk, response, and treatment outcome. This shift is exciting, as we and many others hope it not only will support translation of drug efficacy from animal models to clinical trials but also will potentially improve predictability of stage II for stage III clinical trials.

Evidence that reduced gray matter volume in psychotic disorder is associated with exposure to environmental risk factors

The aim of this study was to examine whether cannabis use, childhood trauma and urban upbringing are associated with total gray matter volume (GMV) in individuals with (risk for) psychotic disorder and whether this is sex-specific. T1-weighted MRI scans were acquired from 89 patients with a psychotic disorder, 95 healthy siblings of patients with psychotic disorder and 87 controls. Multilevel random regression analyses were used to examine main effects and interactions between group, sex and environmental factors in models of GMV. The three-way interaction between group, sex and cannabis (χ² =12.43, p<0.01), as well as developmental urbanicity (χ² = 6.29, p = 0.01) were significant, indicating that cannabis use and developmental urbanicity were associated with lower GMV in the male patient group (cannabis: B= -32.54, p < 0.01; developmental urbanicity: B= -10.23, p=0.03). For childhood trauma, the two-way interaction with group was significant (χ² = 5.74, p = 0.02), indicating that childhood trauma was associated with reduced GMV in the patient group (B=-9.79, p=0.01). The findings suggest that reduction of GMV in psychotic disorder may be the outcome of differential sensitivity to environmental risks, particularly in male patients.

Childhood Maltreatment and Young Adulthood Hallucinations, Delusional Experiences, and Psychosis: A Longitudinal Study

Child maltreatment is a widespread public health problem associated with a range of mental health disorders later in life. In order to effectively address these disorders, there is a need to understand more about the mental health consequences of different types of child maltreatment. This study examines the associations between prospectively substantiated child maltreatment (ages 0-14 y) and reports of hallucinations and delusional experiences at 21 years after birth. As well, we examined 12-month and lifetime psychotic disorders using data from a longitudinal birth cohort. The study comprised 3752 participants from the Mater-University of Queensland Study of Pregnancy, a prospective Australian prebirth cohort study. Psychotic experiences and 12-month and lifetime psychosis were measured using the Achenbach Young Adults Self-Report, the Peter's Delusions Inventory, and Composite International Diagnostic Interview at the 21-year follow-up. In adjusted analyses, those children who had experienced any maltreatment and who were emotionally abused and neglected were more likely to report (1) hallucinations and lifetime delusional experiences and (2) more likely to experience lifetime psychosis than their nonabused counterparts. In expanded models, those exposed to multiple forms of maltreatment, in particular with emotional abuse and neglect, had an increased likelihood of hallucinations and delusional experiences. There is an association between child maltreatment, especially emotional abuse and neglect, and later hallucinations, delusional experiences, and psychosis. It is, however, relevant to note that the vast majority of children experiencing childhood maltreatment do not appear to develop psychotic experiences or psychotic disorder. Further research to determine the reasons for highly variable outcomes of child maltreatment is warranted.

Chronic Vortioxetine Treatment Reduces Exaggerated Expression of Conditioned Fear Memory and Restores Active Coping Behavior in Chronically Stressed Rats

BACKGROUND

Stress is a risk factor for depression and anxiety disorders, disrupting neuronal processes leading to exaggerated fear and compromised coping behaviors. Current antidepressants are only partially effective. Vortioxetine, a novel multimodal antidepressant, is a serotonin transporter inhibitor; 5-HT3, 5-HT7, and 5-HT1D receptor antagonist; 5-HT1B partial agonist; and 5-HT1A agonist. We have shown that chronic dietary vortioxetine administration reversed stress-induced deficits in cognitive flexibility. In the present studies, we investigated the generality of vortioxetine's effects on other stress-related behavioral changes after different types of chronic stress.

METHODS

In experiment 1, rats were fear-conditioned by pairing a tone with footshock, then exposed to chronic plus acute prolonged stress. In experiment 2, rats were exposed to chronic unpredictable stress. In both experiments, beginning on day 4 of chronic stress, vortioxetine was given in the diet (24 mg/kg/d). In experiment 1, effects of vortioxetine were tested on stress-induced changes in retention and extinction of cue-conditioned fear, and in experiment 2, on coping behavior on the shock probe defensive burying test after chronic stress.

RESULTS

Chronic stress exaggerated the expression of conditioned fear memory. Vortioxetine restored fear memory to control levels and rendered extinction in stressed rats comparable with that in controls. In experiment 2, chronic unpredictable stress caused a shift from active to passive coping behavior, and vortioxetine restored active coping.

CONCLUSIONS

Vortioxetine reduced exaggerated expression of conditioned fear and restored adaptive coping behavior following 2 different types of chronic stress, adding to the evidence of its therapeutic potential in the management of depression and anxiety disorders.

EMDR Therapy in Psycho-Oncology: A Bridge Between Mind and Body

Of the many life-threatening illnesses, cancer can be one of the most traumatic and distressful. It impacts the individual’s sense of identity and interferes with essential features intrinsic to the person’s uniqueness and self-awareness. It attacks patients’ physical integrity, bringing death into the foreground and can directly threaten their sense of belonging to micro and macro social systems. This article stresses the importance of understanding that psychological pain and physical suffering are closely interconnected and, within the context of psycho-oncology, proposes a clinical perspective based on the eye movement desensitization and reprocessing (EMDR) approach, in which the cancer event is nested in the history of life of the patient. EMDR is a therapeutic approach guided by the adaptive information processing (AIP) model. The AIP model postulates that psychopathology results when unprocessed experiences are stored in their own neural network, incapable of connecting with other more adaptive networks. In this perspective, the core of the clinical suffering is hypothesized as embedded in these dysfunctionally suspended memories. In line with recent scientific literature presented in this article, it appears that previous and cancer-related traumas maintain a vicious cycle between psychological and physical health, and the aim of EMDR therapy is to break this cycle. Recent scientific research has hypothesized that EMDR therapy is effective at both the psychological and physical levels. However, because of the consistent heterogeneity of the research design, the findings reported in this article highlight the need for further controlled research for more comprehensive examination.

Functional (dissociative) retrograde amnesia

Retrograde amnesia is described as condition which can occur after direct brain damage, but which occurs more frequently as a result of a psychiatric illness. In order to understand the amnesic condition, content-based divisions of memory are defined. The measurement of retrograde memory is discussed and the dichotomy between "organic" and "psychogenic" retrograde amnesia is questioned. Briefly, brain damage-related etiologies of retrograde amnesia are mentioned. The major portion of the review is devoted to dissociative amnesia (also named psychogenic or functional amnesia) and to the discussion of an overlap between psychogenic and "brain organic" forms of amnesia. The "inability of access hypothesis" is proposed to account for most of both the organic and psychogenic (dissociative) patients with primarily retrograde amnesia. Questions such as why recovery from retrograde amnesia can occur in retrograde (dissociative) amnesia, and why long-term new learning of episodic-autobiographic episodes is possible, are addressed. It is concluded that research on retrograde amnesia research is still in its infancy, as the neural correlates of memory storage are still unknown. It is argued that the recollection of episodic-autobiographic episodes most likely involves frontotemporal regions of the right hemisphere, a region which appears to be hypometabolic in patients with dissociative amnesia.

The case for neuropsychoanalysis: Why a dialogue with neuroscience is necessary but not sufficient for psychoanalysis

Recent advances in the cognitive, affective and social neurosciences have enabled these fields to study aspects of the mind that are central to psychoanalysis. These developments raise a number of possibilities for psychoanalysis. Can it engage the neurosciences in a productive and mutually enriching dialogue without compromising its own integrity and unique perspective? While many analysts welcome interdisciplinary exchanges with the neurosciences, termed neuropsychoanalysis, some have voiced concerns about their potentially deleterious effects on psychoanalytic theory and practice. In this paper we outline the development and aims of neuropsychoanalysis, and consider its reception in psychoanalysis and in the neurosciences. We then discuss some of the concerns raised within psychoanalysis, with particular emphasis on the epistemological foundations of neuropsychoanalysis. While this paper does not attempt to fully address the clinical applications of neuropsychoanalysis, we offer and discuss a brief case illustration in order to demonstrate that neuroscientific research findings can be used to enrich our models of the mind in ways that, in turn, may influence how analysts work with their patients. We will conclude that neuropsychoanalysis is grounded in the history of psychoanalysis, that it is part of the psychoanalytic worldview, and that it is necessary, albeit not sufficient, for the future viability of psychoanalysis.

Acute response to psychological trauma and subsequent recovery: no changes in brain structure

We used magnetic resonance imaging to study brain structure in acute stress disorder (ASD) following a psychological trauma and after 4 weeks in remission. Whole-brain voxel-based morphometry and FreeSurfer analysis of the hippocampal formation and amygdala revealed no structural changes in ASD (n=75) compared with trauma-exposed individuals without ASD (n=60) and community controls (n=60). These results suggest that ASD, in contrast to posttraumatic stress disorder, is not characterized by structural brain alterations.

Repetitive transcranial magnetic stimulation for clinical applications in neurological and psychiatric disorders: an overview

Neurological and psychiatric disorders are characterized by several disabling symptoms for which effective, mechanism-based treatments remain elusive. Consequently, more advanced non-invasive therapeutic methods are required. A method that may modulate brain activity and be viable for use in clinical practice is repetitive transcranial magnetic stimulation (rTMS). It is a non-invasive procedure whereby a pulsed magnetic field stimulates electrical activity in the brain. Here, we focus on the basic foundation of rTMS, the main stimulation parametters, the factors that influence individual responses to rTMS and the experimental advances of rTMS that may become a viable clinical application to treat neurological and psychiatric disorders. The findings showed that rTMS can improve some symptoms associated with these conditions and might be useful for promoting cortical plasticity in patients with neurological and psychiatric disorders. However, these changes are transient and it is premature to propose these applications as realistic therapeutic options, even though the rTMS technique has been evidenced as a potential modulator of sensorimotor integration and neuroplasticity. Functional imaging of the region of interest could highlight the capacity of rTMS to bring about plastic changes of the cortical circuitry and hint at future novel clinical interventions. Thus, we recommend that further studies clearly determine the role of rTMS in the treatment of these conditions. Finally, we must remember that however exciting the neurobiological mechanisms might be, the clinical usefulness of rTMS will be determined by its ability to provide patients with neurological and psychiatric disorders with safe, long-lasting and substantial improvements in quality of life.

Attachment and the metabolic syndrome in midlife: the role of interview-based discourse patterns

OBJECTIVE

Adult attachment discourse patterns and current family relationship quality were examined as correlates of health behaviors and number of metabolic syndrome (MetS) criteria met, and as mediators of the link between childhood adversity and these health outcomes.

METHODS

A sample of 215 white/European American and black/African American adults aged 35 to 55 years were examined using a cross-sectional study design. Discourse was assessed with the Adult Attachment Interview, using coherence (a marker of attachment security), unresolved trauma/loss (a marker of disorganized cognitions related to trauma or loss), and idealization (minimizing stressful experiences and their impact) scores. Relationship quality, adverse childhood experiences, and current depressive symptoms were assessed, as were health behaviors of diet, exercise, and smoking. MetS includes obesity, elevated blood pressure, elevated fasting glucose, high triglycerides, and low high-density lipoprotein cholesterol.

RESULTS

Using path analysis and including childhood adversity severity and depressive symptoms in the model, both Adult Attachment Interview coherence and unresolved trauma/loss were directly linked to the number of MetS criteria (r = 0.186 and r = 0.170, respectively). Idealization was indirectly linked to MetS through poor diet (r = 0.183). The final model explained 21% of the variance in scores for the number of MetS criteria met.

CONCLUSIONS

Insecure adult attachment is associated with increased risk of MetS.

Epigenetics, stress, and their potential impact on brain network function: a focus on the schizophrenia diatheses

The recent sociodevelopmental cognitive model of schizophrenia/psychosis is a highly influential and compelling compendium of research findings. Here, we present logical extensions to this model incorporating ideas drawn from epigenetic mediation of psychiatric disease, and the plausible effects of epigenetics on the emergence of brain network function and dysfunction in adolescence. We discuss how gene-environment interactions, effected by epigenetic mechanisms, might in particular mediate the stress response (itself heavily implicated in the emergence of schizophrenia). Next, we discuss the plausible relevance of this framework for adolescent genetic risk populations, a risk group characterized by vexing and difficult-to-explain heterogeneity. We then discuss how exploring relationships between epigenetics and brain network dysfunction (a strongly validated finding in risk populations) can enhance understanding of the relationship between stress, epigenetics, and functional neurobiology, and the relevance of this relationship for the eventual emergence of schizophrenia/psychosis. We suggest that these considerations can expand the impact of models such as the sociodevelopmental cognitive model, increasing their explanatory reach. Ultimately, integration of these lines of research may enhance efforts of early identification, intervention, and treatment in adolescents at-risk for schizophrenia.

Traumagedächtnis bei Kindern mit Posttraumatischer Belastungsstörung

Das Gedächtnis spielt eine wichtige Rolle bei der Entstehung und Behandlung von Posttraumatischer Belastungsstörung (PTBS). Die vorliegende Überblicksarbeit beschäftigt sich mit der Frage nach dem empirischen Nachweis von traumabezogenen Gedächtnisstörungen im Kindesalter. Die bisherigen Untersuchungen zeigen ein heterogenes Bild. Es gibt Hinweise auf eine Beeinträchtigung der Hirnreifungsprozesse sowie der Erinnerungsqualität bei Kindern und Jugendlichen mit PTBS. Jedoch im Gegensatz zu Befunden im Erwachsenenalter wiesen traumatisierte Kinder ein größeres Hippocampusvolumen im Vergleich zur Kontrollgruppe auf. Die Zusammenschau der Befunde macht den großen Bedarf an weiterführenden Untersuchungen deutlich.

MR diffusion tensor imaging detects rapid microstructural changes in amygdala and hippocampus following fear conditioning in mice

BACKGROUND

Following fear conditioning (FC), ex vivo evidence suggests that early dynamics of cellular and molecular plasticity in amygdala and hippocampal circuits mediate responses to fear. Such altered dynamics in fear circuits are thought to be etiologically related to anxiety disorders including posttraumatic stress disorder (PTSD). Consistent with this, neuroimaging studies of individuals with established PTSD in the months after trauma have revealed changes in brain regions responsible for processing fear. However, whether early changes in fear circuits can be captured in vivo is not known.

METHODS

We hypothesized that in vivo magnetic resonance diffusion tensor imaging (DTI) would be sensitive to rapid microstructural changes elicited by FC in an experimental mouse PTSD model. We employed a repeated measures paired design to compare in vivo DTI measurements before, one hour after, and one day after FC-exposed mice (n=18).

RESULTS

Using voxel-wise repeated measures analysis, fractional anisotropy (FA) significantly increased then decreased in amygdala, decreased then increased in hippocampus, and was increasing in cingulum and adjacent gray matter one hour and one day post-FC respectively. These findings demonstrate that DTI is sensitive to early changes in brain microstructure following FC, and that FC elicits distinct, rapid in vivo responses in amygdala and hippocampus.

CONCLUSIONS

Our results indicate that DTI can detect rapid microstructural changes in brain regions known to mediate fear conditioning in vivo. DTI indices could be explored as a translational tool to capture potential early biological changes in individuals at risk for developing PTSD.

Chronic stress alters inhibitory networks in the medial prefrontal cortex of adult mice

Chronic stress in experimental animals induces dendritic atrophy and decreases spine density in principal neurons of the medial prefrontal cortex (mPFC). This structural plasticity may play a neuroprotective role and underlie stress-induced behavioral changes. Different evidences indicate that the prefrontocortical GABA system is also altered by stress and in major depression patients. In the amygdala, chronic stress induces dendritic remodeling both in principal neurons and in interneurons. However, it is not known whether similar structural changes occur in mPFC interneurons. The polysialylated form of the neural cell adhesion molecule (PSA-NCAM) may mediate these changes, because it is known to influence the dendritic organization of adult cortical interneurons. We have analyzed the dendritic arborization and spine density of mPFC interneurons in adult mice after 21 days of restraint stress and have found dendritic hypertrophy in a subpopulation of interneurons identified mainly as Martinotti cells. This aversive experience also decreases the number of glutamate decarboxylase enzyme, 67 kDa isoform (GAD67) expressing somata, without affecting different parameters related to apoptosis, but does not alter the number of interneurons expressing PSA-NCAM. Quantitative retrotranscription-polymerase chain reaction (qRT-PCR) analysis of genes related to general and inhibitory neurotransmission and of PSA synthesizing enzymes reveals increases in the expression of NCAM, synaptophysin and GABA(A)α1. Together these results show that mPFC inhibitory networks are affected by chronic stress and suggest that structural plasticity may be an important feature of stress-related psychiatric disorders where this cortical region, specially their GABAergic system, is altered.

Schizophrenia patients with a history of childhood trauma have a pro-inflammatory phenotype

BACKGROUND

Increasing evidence indicates that childhood trauma is a risk factor for schizophrenia and patients with this syndrome have a pro-inflammatory phenotype. We tested the hypothesis that the pro-inflammatory phenotype in schizophrenia is associated with childhood trauma and that patients without a history of such trauma have a similar immune profile to healthy controls.

METHOD

We recruited 40 schizophrenia patients and 40 controls, all of whom completed the Childhood Trauma Questionnaire (CTQ). Using enzyme-linked immunosorbent assay (ELISA) techniques, we measured peripheral levels of interleukin (IL)-1β, IL-6, IL-8 and tumour necrosis factor (TNF)-α. These immune parameters were compared in schizophrenia with childhood trauma, schizophrenia without childhood trauma and healthy controls.

RESULTS

Patients with childhood trauma had higher levels of IL-6 and TNF-α than patients without trauma and healthy controls, and TNF-α levels correlated with the extent of the trauma. Patients with no trauma had similar immune profiles to controls.

CONCLUSIONS

Childhood trauma drives changes, possibly epigenetic, that generate a pro-inflammatory phenotype.

Further validation of the psychological injury risk indicator scale

OBJECTIVE

Confirm the Psychological Injury Risk Indicator (PIRI) scale capacity to facilitate routine assessment of psychological health of workers in high-stress environments.

METHOD

A cross-sectional study compared the PIRI scale scores with two experienced clinical psychologists' assessment of defined psychological injury in 93 participants. A second, longitudinal, study assessed PIRI predictive capacity for emotional exhaustion, physical health, and work engagement in 420 participants over 14 months.

RESULTS

The PIRI scale was shown to (a) determine the degree of psychological injury in participants with high correspondence to a specialist clinical interview; and (b) predict future emotional exhaustion, physical health, and work engagement to a significantly better degree than the 12-item General Health Questionnaire and Kessler-10 measures.

CONCLUSIONS

The PIRI scale shows a valuable capacity to provide accurate routine psychological health assessment for at-risk workers in high-strain work environments.

Hypothalamic-pituitary-adrenal axis dysfunction as a neurobiological correlate of emotion dysregulation in adolescent suicide

BACKGROUND

Biological markers of vulnerability for current or future risk of suicide in adolescents could be important adjuncts to the treatment and prevention of this phenomenon.

DATA SOURCES

We conducted a PubMed search of all English-language articles published between January 1990 and June 2011 using the following search terms: ("hypothalamic-pituitary-adrenal" OR "HPA") AND ("adolescence" OR "adolescent" OR "teenager") AND ("depression" OR "major depressive disorder" OR "suicidal behavior" OR "suicidal ideation" OR "suicidal thoughts" OR "deliberate self-harm" OR "suicidal attempt" OR "suicide").

RESULTS

HPA axis activity can be examined using different methods that do not have the same biological interpretation. An abnormal HPA axis functioning together with an anomalous interaction between HPA mechanisms and other systems such as the serotonergic system may be one of the neurobiological correlates of emotion dysregulation (ED). ED may play an important role in adolescent suicidal behavior. Some psychopathological conditions such as depression or childhood psychological trauma that increase suicidal risk in adolescents are also associated with HPA axis dysregulation. ED, a personality trait, can also be viewed as a predisposing factor that augments the vulnerability to suffer from psychiatric conditions.

CONCLUSIONS

Correlating HPA axis dysfunction with psychological factors such as ED could lead to a better understanding of the role of HPA abnormalities in adolescent suicide and may enhance preventive and treatment strategies.

Acute minocycline treatment mitigates the symptoms of mild blast-induced traumatic brain injury

Mild traumatic brain injury (mTBI) represents a significant challenge for the civilian and military health care systems due to its high prevalence and overall complexity. Our earlier works showed evidence of neuroinflammation, a late onset of neurobehavioral changes, and lasting memory impairment in a rat model of mild blast-induced TBI (mbTBI). The aim of our present study was to determine whether acute treatment with the non-steroidal anti-inflammatory drug minocycline (Minocin^®) can mitigate the neurobehavioral abnormalities associated with mbTBI, Furthermore, we aimed to assess the effects of the treatment on select inflammatory, vascular, neuronal, and glial markers in sera and in brain regions associated with anxiety and memory (amygdala, prefrontal cortex, ventral, and dorsal hippocampus) following the termination (51 days post-injury) of the experiment. Four hours after a single exposure to mild blast overpressure or sham conditions, we treated animals with a daily dose of minocycline (50 mg/kg) or physiological saline (vehicle) for four consecutive days. At 8 and 45 days post-injury, we tested animals for locomotion, anxiety, and spatial memory. Injured animals exhibited significantly impaired memory and increased anxiety especially at the later testing time point. Conversely, injured and minocycline treated rats’ performance was practically identical to control (sham) animals in the open field, elevated plus maze, and Barnes maze. Protein analyses of sera and brain regions showed significantly elevated levels of all of the measured biomarkers (except VEGF) in injured and untreated rats. Importantly, minocycline treatment normalized serum and tissue levels of the majority of the selected inflammatory, vascular, neuronal, and glial markers. In summary, acute minocycline treatment appears to prevent the development of neurobehavioral abnormalities likely through mitigating the molecular pathologies of the injury in an experimental model of mbTBI.

Different white matter abnormalities between the first-episode, treatment-naive patients with posttraumatic stress disorder and generalized anxiety disorder without comorbid conditions

BACKGROUND

This study compared brain white matter integrity in two groups of patients with DSM-IV anxiety disorders.

METHOD

Seventeen patients with posttraumatic stress disorder (PTSD), 20 with generalized anxiety disorder (GAD), and 28 healthy controls were assessed on diffusion tensor imaging.

RESULTS

As compared to healthy controls, increased fractional anisotropy (FA) in left superior frontal gyrus in PTSD patients, and increased FA in right postcentral gyrus in GAD subjects were exhibited. Furthermore, patients with PTSD showed reduced FA in right anterior cingulate gyrus relative to GAD subjects. However, there was no significant correlation between the FA value of any altered region and the severity of PTSD or GAD.

LIMITATIONS

The sample studied can be considered small. Gender and educational level were not well-matched among the groups.

CONCLUSIONS

We tentatively speculate that abnormal white matter integrity of right anterior cingulate gyrus is an important neuroimaging marker of PTSD that distinguishes it from other anxiety disorders such as GAD.

Is rTMS an effective therapeutic strategy that can be used to treat anxiety disorders?

Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive procedure whereby a pulsed magnetic field stimulates electrical activity in the brain. Anxiety disorders are the most common of all mental health problems for which effective, mechanism-based treatments remain elusive. Consequently, more advanced non-invasive therapeutic methods are required. A possible method to modulate brain activity and potentially viable for use in clinical practice is rTMS. Here, we focus on the main findings of rTMS from animal models of anxiety and the experimental advances of rTMS that may become a viable clinical application to treat anxiety disorders, one of the most common causes of disability in the workplace in the world. Key advances in combining rTMS with neuroimaging technology may aid such future developments. This article is part of a Special Issue entitled 'Anxiety and Depression'.

Psychotic symptoms in young adults exposed to childhood trauma--a 20 year follow-up study

Childhood adversity has been shown to increase the risk of psychotic symptoms in adult life. However, there are no previous studies looking at the association between experiencing a natural disaster during childhood and the development of psychotic symptoms in young adulthood. Eight hundred and six bushfire-exposed children and 725 control children were evaluated following the 1983 South Australian bushfires. Five hundred and twenty nine (65.6%) of the bushfire group and 464 (64%) controls participated in a follow up study 20 years later. Childhood data on emotional and behavioural disorders and dysfunctional parenting was available. The adult assessment included the Australian National Health and Well-Being psychosis screen and detailed information about trauma, childhood adversity and alcohol and cannabis abuse. 5.6% of subjects responded positively to the psychosis screen and 2.6% responded positively to a further probe question. Psychotic symptoms were more common in subjects exposed to a greater number of traumas, and were associated with higher rates of childhood adversity, emotional and behavioural disturbance, dysfunctional parenting, and alcohol and cannabis abuse. Subjects exposed to bushfires as children did not have a greater risk of psychosis. Our results indicate that exposure to multiple traumas, rather than a single major trauma, increases the risk of later psychosis.

Reduced cortical thickness as an outcome of differential sensitivity to environmental risks in schizophrenia

BACKGROUND

The etiology of schizophrenia is thought to involve differential-likely genetically mediated-sensitivity to environmental exposures. However, examination of differential sensitivity in models of psychopathologic constructs is subject to bias because psychopathology itself may distort exposure assessment. The use of neuroimaging phenotypes, conversely, may provide unbiased evidence for differential sensitivity to environmental exposures. This study examined the impact of two environmental exposures associated with both schizophrenia and magnetic resonance imaging (MRI) cerebral alterations in models of cerebral cortical thickness.

METHODS

T1-weighted MRI scans were acquired from 88 patients with schizophrenia, 98 healthy siblings at higher than average genetic risk for schizophrenia, and 87 control subjects. Freesurfer software was used to measure cortical thickness for 68 brain regions. Associations between 1) cortical thickness and 2) cannabis use and developmental trauma were examined.

RESULTS

A significant group × developmental trauma interaction (χ(2) = 9.65, p = .01), as well as a significant group × cannabis interaction (χ(2) = 6.04, p = .05) was apparent, indicating differential sensitivity of the patient group, which displayed stronger reductions of cortical thickness for both exposures. A similar pattern was found in the sibling-control comparison for cannabis. For developmental trauma, siblings did not differ from control subjects, displaying an increase in cortical thickness with higher levels of trauma.

CONCLUSIONS

The findings suggest that schizophrenia and its genetic liability are associated with differential cerebral cortical sensitivity to developmental environmental exposures such as cannabis. Gene-environment interactions may underlie some of the brain alterations observed in patients with schizophrenia and their relatives.

Support for religio-political aggression among teenaged boys in Gaza: part II: neuroendocrinological findings

Hormones seem to play important roles in the regulation of human aggression. Multiple studies have confirmed that testosterone (T) levels exhibit complex relationships with aggression, dominance, and/or risk-taking behavior. Some evidence suggests that cortisol (CORT) interacts with T and may also be associated with aspects of mood and aggression. However, almost no research to date has investigated the possibility that these neuroendocrine factors are associated with variations in political attitudes or with political aggression. During the second intifada, we tested the hypothesis that morning salivary T and/or salivary CORT levels might be associated with self-rated aggression or with support for religio-political aggression (RPA) among 14-year-old Palestinian boys living in Gaza. We obtained and averaged weekly 09:00 hr salivary measures of T and CORT for more than 1 month. Averaged morning T levels did not correlate with self-rated aggression, but were positively associated with agreement with the statement "religious ends justify any means," (r = .355, P = .014) and marginally associated with a composite measure of support for RPA (r = .247, P = .094). Average CORT levels were inversely correlated with self-rated aggression (r = -.328, P = .037) and with anger (r = -.373, P = .016), but CORT levels were not associated with support for RPA or with the statement "religious ends justify any means." Acknowledging that a modest sample size and methodological issues necessarily limit confidence in our conclusions, these results may represent the first findings regarding neurobiological correlates of support for political aggression.