Changes in the dynamic network structure of PTSD symptoms pre-to-post combat.

BACKGROUND: Combat exposure is associated with elevated risk for post-traumatic stress disorder (PTSD). Despite considerable research on PTSD symptom clustering, it remains unknown how symptoms of PTSD re-organize following combat. Network analysis provides a powerful tool to examine such changes. METHODS: A network analysis approach was taken to examine how symptom networks change from pre- to post-combat using longitudinal prospective data from a cohort of infantry male soldiers (Mage = 18.8 years). PTSD symptoms measured using the PTSD Checklist (PCL) were assessed after 6 months of combat training but before deployment and again after 6 months of combat (Ns = 910 and 725 at pre-deployment and post-combat, respectively). RESULTS: Stronger connectivity between PTSD symptoms was observed post-combat relative to pre-deployment (global strength values of the networks were 7.54 pre v. 7.92 post; S = .38, p < 0.05). Both the re-experiencing symptoms cluster (1.92 v. 2.12; S = .20, p < 0.03) and the avoidance symptoms cluster (2.61 v. 2.96; S = .35, p < 0.005) became more strongly inter-correlated post-combat. Centrality estimation analyses revealed that psychological reaction to triggers was central and linked the intrusion and avoidance sub-clusters at post-combat. The strength of associations between the arousal and reactivity symptoms cluster remained stable over time (1.85 v. 1.83; S = .02, p = .92). CONCLUSIONS: Following combat, PTSD symptoms and particularly the re-experiencing and avoidance clusters become more strongly inter-correlated, indicating high centrality of trigger-reactivity symptoms.

Functioning of Young Adults With ADHD in the Military.

Objective: To assess the functioning of young adults with ADHD in a military setting. Method: In all, 14,655 young adults with ADHD (mean age at first examination 17.8 ± 0.7) attending mandatory service in the Israeli military were compared with matched controls on several functioning domains. Results: Young adults with ADHD had more sessions with mental health care professionals, physician appointments, sick days, and disqualifications of professions than controls (p < .001). Young adults with ADHD were also less medically fit for combat service (odds ratio [OR] = 0.75, 95% confidence interval [CI] = [0.72, 0.79]), more medically unfit for military service in general (OR = 1.26, 95% CI = [1.13, 1.40]), and had higher rates of overweight and obesity (p < .001). In addition, they were more likely to be diagnosed with a personality disorder (OR = 1.29, 95% CI = [1.07, 1.53]) or with minor affective and anxiety disorders (OR = 1.33, 95% CI = [1.06, 1.67]) than matched controls. Conclusion: These results support a negative effect of ADHD on the functioning of young adults in a military setting.

Electrical fingerprint of the amygdala guides neurofeedback training for stress resilience.

Real-time functional magnetic resonance imaging (rt-fMRI) has revived the translational perspective of neurofeedback (NF)1. Particularly for stress management, targeting deeply located limbic areas involved in stress processing2 has paved new paths for brain-guided interventions. However, the high cost and immobility of fMRI constitute a challenging drawback for the scalability (accessibility and cost-effectiveness) of the approach, particularly for clinical purposes3. The current study aimed to overcome the limited applicability of rt-fMRI by using an electroencephalography (EEG) model endowed with improved spatial resolution, derived from simultaneous EEG-fMRI, to target amygdala activity (termed amygdala electrical fingerprint (Amyg-EFP))4-6. Healthy individuals (n = 180) undergoing a stressful military training programme were randomly assigned to six Amyg-EFP-NF sessions or one of two controls (control-EEG-NF or NoNF), taking place at the military training base. The results demonstrated specificity of NF learning to the targeted Amyg-EFP signal, which led to reduced alexithymia and faster emotional Stroop, indicating better stress coping following Amyg-EFP-NF relative to controls. Neural target engagement was demonstrated in a follow-up fMRI-NF, showing greater amygdala blood-oxygen-level-dependent downregulation and amygdala-ventromedial prefrontal cortex functional connectivity following Amyg-EFP-NF relative to NoNF. Together, these results demonstrate limbic specificity and efficacy of Amyg-EFP-NF during a stressful period, pointing to a scalable non-pharmacological yet neuroscience-based training to prevent stress-induced psychopathology.

Author Correction: Electrical fingerprint of the amygdala guides neurofeedback training for stress resilience.

The original and corrected Acknowledgements are shown in the accompanying Author Correction.

Depression and impulsiveness among soldiers who died by suicide: A psychological autopsy study.

INTRODUCTION: Despite the accumulated knowledge about suicide, suicidal acts remain difficult to predict, and many suicides are acted out impulsively. METHODS: We performed a psychological autopsy study based on inquiries about the deaths of all male soldiers aged 18-21 years who served in the Israeli army and died by suicide between 2009 and 2013 (n = 69). The study population was first divided into two groups: those who had depressive disorder (n = 31); and those who did not (n = 38). Socio-demographic characteristics of the subjects and the characteristics of the suicidal act were compared. Afterwards, the study population was re-divided by the presence or absence of impulsive personality traits (n = 22, and n = 47, respectively), and investigated for distinct suicidal behavior features. RESULTS: No significant socio-demographic differences were found between the depressed and non-depressed suicide victims. The depressed group had showed more signs of planning the act (47% vs. 23%), and had expressed suicidal ideation in the days preceding the suicide (51.6% vs. 21%). One third of the subjects were found to have an impulsive personality trait, with significantly more histories of disciplinary issues, violence and cluster B personality disorders. Alcohol use during the act was significantly more prevalent among impulsive than non-impulsive subjects (45.4% vs. 14.9%). CONCLUSION: Identification of distinct clinical groups of suicide victims among young males might help clinicians evaluate high risk cases, and may provide valuable opportunities to alleviate and prevent these events in the future.

Acute delivery of attention bias modification training (ABMT) moderates the association between combat exposure and posttraumatic symptoms: A feasibility study.

Combat deployment enhances risk for posttraumatic stress symptoms. We assessed whether attention bias modification training (ABMT), delivered immediately prior to combat, attenuates the association between combat exposure and stress-related symptoms. 99 male soldiers preparing for combat were randomized to receive either an ABMT condition designed to enhance vigilance toward threat or an attention control training (ACT) designed to balance attention deployment between neutral and threat words. Frequency of combat events, and symptoms of PTSD and depression were measured prior to deployment and at a two-month follow-up. Regression analysis revealed that combat exposure uniquely accounted for 4.6% of the variance in stress-related symptoms change from baseline to follow-up and that the interaction between ABMT and combat exposure accounted for additional 5.4% of the variance. Follow-up analyses demonstrate that ABMT moderated the association between combat exposure and symptoms. ABMT appear to have potential as a preventative intervention to reduce risk for stress-related symptoms associated with combat exposure.

The impact of Herpes simplex virus type 1 on cognitive impairments in young, healthy individuals - A historical prospective study.

Herpes simplex virus (HSV) is a highly prevalent neurotropic virus. Although on the whole, chronic, latent or persistent infection is considered to be relatively benign, HSV infections can cause cognitive impairment during and after acute encephalitis. Some studies have documented cognitive impairment in exposed persons that is untraceable to encephalitis. Most studies have focused on these impairments in the mentally ill, mostly among individuals with schizophrenia, and only recently have studies begun to examine the impact of HSV infection on the cognition of healthy individuals. Subjects were a representative, random sample of 612 soldiers before active duty in the Israeli military (Israeli defense force - IDF), 62.2% HSV positive (n=381) and 38.8% HSV negative (n=231). Cognitive functioning and language abilities were compared between these groups, controlling for years of education, immigration status, and gender. Compared to soldiers who were sero-negative, soldiers who were sero-positive for HSV had significantly lower IQ scores (IQ=97.96, SD=15.19 vs IQ=103.23, SD=14.23; p≤0.001, effect size (ES)=0.2), and significantly lower Hebrew language scores (ES=0.1, p≤0.01). The results remained significant after removing subjects with mild depression, anxiety or personality disorders. Although we could not control for socio-economic status directly, our findings indicate that infection with HSV-1 is associated with reduced cognitive functioning in healthy individuals. This finding adds to the growing number of studies in the schizophrenia literature and indicates that many research findings seemingly characteristic of schizophrenia are related to the association between HSV exposure and cognitive functioning in general, and are not illness specific.

A population-based longitudinal study of suicide risk in male schizophrenia patients: Proximity to hospital discharge and the moderating effect of premorbid IQ.

Suicide is a major cause of death in schizophrenia. Identifying factors which increase the risk of suicide among schizophrenia patients might help focus prevention efforts. This study examined risk of suicide in male schizophrenia patients using population-based data, examining the timing of suicide in relation to the last hospital discharge, and the effect of premorbid IQ on risk of suicide. Data on 930,000 male adolescents from the Israeli military draft board were linked with data from the Israeli Psychiatric Hospitalization Case Registry and vital statistics from the Israeli Ministry of Health. The relationship between premorbid IQ and risk for suicide was examined among 2881 males hospitalized with schizophrenia and compared to a control group of 566,726 males from the same cohort, who were not hospitalized for a psychiatric disorder, using survival analysis methods. Over a mean follow-up period of 9.9 years (SD=5.8, range: 0-22 years), 77/3806 males with schizophrenia died by suicide (a suicide rate of 204.4 per 100,000 person-years). Approximately 48% of the suicides occurred within a year of discharge from the last hospital admission for schizophrenia. Risk of suicide was higher in male schizophrenia patients with high premorbid IQ (HR=4.45, 95% CI=1.37-14.43) compared to those with normal premorbid IQ. These data indicate that male schizophrenia patients with high premorbid IQ are at particularly high risk of suicide, and the time of peak risk is during the first year after the last hospitalization discharge.