Mapping the Pathways Between Posttraumatic Stress Disorder, Depression, and Alcohol and Cannabis Use: A Network Analysis.

Objective: The present study examines the network structure and, using Bayesian network analysis, estimates the directional pathways among symptoms of posttraumatic stress disorder (PTSD), major depressive disorder (MDD), and levels of alcohol and cannabis use. Method: A sample of 1471 adults in the United States, who reported at least one potentially traumatic event, completed the PTSD Checklist (PCL-5), Patient Health Questionnaire (PHQ-9), and the Alcohol/Cannabis Use Disorders Identification Test (AUDIT/CUDIT). A regularized partial correlation network provided estimates of symptoms clusters and connections. Directional pathways within the network were then estimated using a directed acyclic graph (DAG). Results: Symptoms clustered in theoretically consistent ways. Risky behavior demonstrated the highest strength centrality and bridge strength. Neither alcohol nor cannabis use appeared central in the network, and DAG results suggested that MDD and PTSD symptoms are more likely to lead to substance use than the other way around. Conclusions: Results suggest that cannabis use is largely connected to alcohol use. Consistent with prior research, risky behavior appeared to be the primary bridge between substance use and PTSD. The direction of associations between substance use and psychological symptoms requires further attention.

Anatomy and dietary specialization influence sensory behaviour among sympatric primates.

Senses form the interface between animals and environments, and provide a window into the ecology of past and present species. However, research on sensory behaviours by wild frugivores is sparse. Here, we examine fruit assessment by three sympatric primates (Alouatta palliata, Ateles geoffroyi and Cebus imitator) to test the hypothesis that dietary and sensory specialization shape foraging behaviours. Ateles and Cebus groups are comprised of dichromats and trichromats, while all Alouatta are trichomats. We use anatomical proxies to examine smell, taste and manual touch, and opsin genotyping to assess colour vision. We find that the frugivorous spider monkeys (Ateles geoffroyi) sniff fruits most often, omnivorous capuchins (Cebus imitator), the species with the highest manual dexterity, use manual touch most often, and that main olfactory bulb volume is a better predictor of sniffing behaviour than nasal turbinate surface area. We also identify an interaction between colour vision phenotype and use of other senses. Controlling for species, dichromats sniff and bite fruits more often than trichromats, and trichromats use manual touch to evaluate cryptic fruits more often than dichromats. Our findings reveal new relationships among dietary specialization, anatomical variation and foraging behaviour, and promote understanding of sensory system evolution.

Empirical Evaluation of Rainbow Reflections: A Comic Book Anthology on Body Image for Queer Men.

Gay, bisexual, and queer (GBQ) men are at higher risk of negative body image. As having a negative body image is related to negative mood, sexual, and health outcomes, identifying and providing community-friendly tools for GBQ men is important. This paper describes the creation and evaluation of Rainbow Reflections, a comic anthology developed to promote awareness of and communication about body image. Rainbow Reflections includes comics from 38 trans- and cis-GBQ artists who drew inspiration from personal narratives based on pre-determined themes in the empirical literature and interactive inserts based on evidence-based practice. To evaluate Rainbow Reflections, 167 trans- and cis-GBQ men completed pre-post measures before/after viewing a selection of comics and responded to an open-ended question about their experience. Overall, participants rated the comic book positively, with a majority (61.1%) indicating that they would recommend the book to a friend. After viewing the comics, participants reported greater comfort with initiating conversations about body image, greater satisfaction with their bodies, and reported higher estimates of how common body image concerns are for queer men. Themes that emerged from open-ended responses included participants reflecting on personal struggles (~ 30%), relating with the stories of others (~ 22%), reflecting on the standards of queer men (~ 18%), recognizing cis-privilege (~ 11%), reflecting on others' struggles (~ 9%), negative feedback about the comics (~ 7%), and balancing masculine and feminine (~ 3%). Results of the study provide preliminary evidence for Rainbow Reflections as an effective community-friendly tool to promote awareness of and communication about body image for GBQ men.

Sarm1 is not necessary for activation of neuron-intrinsic growth programs yet required for the Schwann cell repair response and peripheral nerve regeneration.

Upon peripheral nervous system (PNS) injury, severed axons undergo rapid SARM1-dependent Wallerian degeneration (WD). In mammals, the role of SARM1 in PNS regeneration, however, is unknown. Here we demonstrate that Sarm1 is not required for axotomy induced activation of neuron-intrinsic growth programs and axonal growth into a nerve crush site. However, in the distal nerve, Sarm1 is necessary for the timely induction of the Schwann cell (SC) repair response, nerve inflammation, myelin clearance, and regeneration of sensory and motor axons. In Sarm1-/- mice, regenerated fibers exhibit reduced axon caliber, defective nerve conduction, and recovery of motor function is delayed. The growth hostile environment of Sarm1-/- distal nerve tissue was demonstrated by grafting of Sarm1-/- nerve into WT recipients. SC lineage tracing in injured WT and Sarm1-/- mice revealed morphological differences. In the Sarm1-/- distal nerve, the appearance of p75NTR+, c-Jun+ SCs is significantly delayed. Ex vivo, p75NTR and c-Jun upregulation in Sarm1-/- nerves can be rescued by pharmacological inhibition of ErbB kinase. Together, our studies show that Sarm1 is not necessary for the activation of neuron intrinsic growth programs but in the distal nerve is required for the orchestration of cellular programs that underlie rapid axon extension.

Activity budget and gut microbiota stability and flexibility across reproductive states in wild capuchin monkeys in a seasonal tropical dry forest.

BACKGROUND: Energy demands associated with pregnancy and lactation are significant forces in mammalian evolution. To mitigate increased energy costs associated with reproduction, female mammals have evolved behavioural and physiological responses. Some species alter activity to conserve energy during pregnancy and lactation, while others experience changes in metabolism and fat deposition. Restructuring of gut microbiota with shifting reproductive states may also help females increase the energy gained from foods, especially during pregnancy. The goal of this study was to examine the relationships among behaviour, gut microbiota composition, and reproductive state in a wild, non-human primate to better understand reproductive ecology. We combined life history data with > 13,000 behavioural scans and 298 fecal samples collected longitudinally across multiple years from 33 white-faced capuchin monkey (Cebus imitator) females. We sequenced the V4 region of the 16S rRNA gene and used the DADA2 pipeline to analyze microbial diversity. We used PICRUSt2 to assess putative functions. RESULTS: Reproductive state explained some variation in activity, but overall resting behaviours were relatively stable across pregnancy and lactation. Foraging was less frequent among females in the early stage of nursing compared to the cycling stage, though otherwise remained at comparable levels. Maximum temperature was a strong, significantly positive predictor of resting, while social dominance had a small but significantly negative effect on resting. Ecological variables such as available fruit biomass and rainfall had a small but significantly positive effects on measures of foraging time. Gut microbial community structure, including richness, alpha diversity, and beta diversity remained stable across the reproductive cycle. In pairwise comparisons, pregnant females exhibited increased relative abundances of multiple microbial ASVs, suggesting small changes in relation to reproductive state. Reproductive state was not linked to differential abundance of putative metabolic pathways. CONCLUSIONS: Previous data suggest that activity budget and the gut microbiome shifts considerably during reproduction. The present study finds that both activity and gut microbial communities are less associated with reproduction compared to other predictors, including ecological contexts. This suggests that behavioural flexibility and gut microbial community plasticity is contrained by ecological factors in this population. These data contribute to a broader understanding of plasticity and stability in response to physiological shifts associated with mammalian reproduction.

The relationship between tonic immobility and the development, severity, and course of posttraumatic stress disorder: Systematic and meta-analytic literature review.

BACKGROUND: Tonic immobility (TI) is a reflexive, involuntary response that causes motor inhibition, vocal suppression, and analgesia. TI is elicited by extreme fear and perception of entrapment in a life-threatening situation. Research suggests that TI is a frequent peritraumatic response and may be related to subsequent posttraumatic stress disorder (PTSD). However, findings are mixed and, as of yet, no systematic or meta-analytic review examining associations between TI and PTSD has been published. OBJECTIVE: We systematically and meta-analytically reviewed the literature and investigated whether TI is associated with the development, severity, and course of PTSD. Additionally, we evaluated whether different types of traumatic events are differentially associated with TI, and whether TI severity differs according to sex. METHODS: A systematic literature search was conducted using Embase, PubMed, PsycINFO, and Scopus. Meta-analyses were performed on the included articles. RESULTS: We identified 27 eligible articles. We found a significant association between TI and PTSD symptom severity (r = 0.39, 95% CI: 0.34-0.44; p < .0001). TI was more severe among females (Cohen's d=0.37, 95% CI: 0.25-0.48; p < .0001) and was more often elicited in situations involving interpersonal violence. We found limited longitudinal data to perform a meta-analysis of the association between TI and the development and/or course of PTSD. However, the literature available seems to support the role of TI in both the development and course of PTSD. CONCLUSIONS: Peritraumatic TI is associated with PTSD symptom severity, occurs more often during interpersonal violence, and is more severe among females. More longitudinal research is needed to investigate the role of TI in psychopathology development and course.

The impact of neighborhood context on telomere length: A systematic review.

A growing body of research demonstrates the association between neighborhood context and health. The underlying biological mechanisms of this association are not fully understood. We conducted a systematic review of studies that investigated the association between neighborhood context and telomere length (TL), a DNA-protein complex that shortens after cell division. Short TL is linked to age-related diseases and may be impacted by chronic stress. Nineteen eligible articles identified through PubMed and Scopus met inclusion criteria. Results demonstrated inconsistent support for the relationship between neighborhood disadvantage and short TL. However, findings across several studies provide evidence for an inverse association between perceived neighborhood problems and TL, suggesting that TL may be an important factor in understanding health vulnerabilities associated specifically with negative perceptions of the neighborhood context.

Neuroinflammation: Breaking barriers and bridging gaps.

Neurons are the cells of the nervous system and are responsible for every thought, movement and perception. Immune cells are the cells of the immune system, constantly protecting from foreign pathogens. Understanding the interaction between the two systems is especially important in disease states such as autoimmune or neurodegenerative disease. Unfortunately, this interaction is typically detrimental to the host. However, recent efforts have focused on how neurons and immune cells interact, either directly or indirectly, following traumatic injury to the nervous system. The outcome of this interaction can be beneficial - leading to successful neural repair, or detrimental - leading to functional deficits, depending on where the injury occurs. This review will discuss our understanding of neuron-immune cell interactions after traumatic injury to both the peripheral and central nervous system.

Mental health responses to COVID-19 around the world.

Background: The mental health impact of the COVID-19 crisis may differ from previously studied stressful events in terms of psychological reactions, specific risk factors, and symptom severity across geographic regions worldwide. Objective: To assess the impact of COVID-19 on a wide range of mental health symptoms, to identify relevant risk factors, to identify the effect of COVID-19 country impact on mental health, and to evaluate regional differences in psychological responses to COVID-19 compared to other stressful events. Method: 7034 respondents (74% female) participated in the worldwide Global Psychotrauma Screen - Cross-Cultural responses to COVID-19 study (GPS-CCC), reporting on mental health symptoms related to COVID-19 (n = 1838) or other stressful events (n = 5196) from April to November 2020. Results: Events related to COVID-19 were associated with more mental health symptoms compared to other stressful events, especially symptoms of PTSD, anxiety, depression, insomnia, and dissociation. Lack of social support, psychiatric history, childhood trauma, additional stressful events in the past month, and low resilience predicted more mental health problems for COVID-19 and other stressful events. Higher COVID-19 country impact was associated with increased mental health impact of both COVID-19 and other stressful events. Analysis of differences across geographic regions revealed that in Latin America more mental health symptoms were reported for COVID-19 related events versus other stressful events, while the opposite pattern was seen in North America. Conclusions: The mental health impact of COVID-19-related stressors covers a wide range of symptoms and is more severe than that of other stressful events. This difference was especially apparent in Latin America. The findings underscore the need for global screening for a wide range of mental health problems as part of a public health approach, allowing for targeted prevention and intervention programs.

Antecedentes: El impacto de la crisis por la COVID-19 sobre la salud mental podría diferir de otros eventos estresantes estudiados con anterioridad en relación con reacciones psicológicas, factores de riesgo específicos y severidad de síntomas en diferentes regiones geográficas alrededor del mundo. Objetivo: Evaluar el impacto de la COVID-19 sobre una amplia variedad de síntomas de salud mental, identificar los factores de riesgo relevantes, identificar el efecto que el impacto de la COVID-19 sobre un país ejerce, a su vez, sobre la salud mental, y evaluar las diferencias regionales en las respuestas psicológicas a la COVID-19 comparadas con otros eventos estresantes. Método: 7034 encuestados (74 % mujeres) participaron en el Mapeo Global de Psicotrauma ­ Estudio de Respuestas Transculturales frente a la COVID-19(GPS­CCC, por sus siglas en ingles), reportando síntomas de salud mental relacionados a la COVID-19 (n = 1838) u otros eventos estresantes (n = 5196) de abril a noviembre del 2020. Resultados: Los eventos relacionados a la COVID-19 se asociaron con un mayor número de síntomas de salud mental comparados con otros eventos estresantes, especialmente con síntomas del trastorno de estrés postraumático, ansiedad, depresión, insomnio, y disociación. La falta de apoyo social, los antecedentes psiquiátricos, el trauma infantil, los eventos estresantes adicionales ocurridos en el último mes y una baja resiliencia predijeron tener mayores problemas de salud mental por la COVID-19 y otros eventos estresantes. Un impacto más alto ejercido por la COVID-19 sobre un país se asoció, a su vez, con un mayor impacto sobre la salud mental, tanto por la COVID-19 como por otros eventos estresantes. Un análisis de las diferencias entre regiones geográficas reveló que en Latinoamérica se reportaron más síntomas de salud mental asociados a eventos relacionados con la COVID-19 en comparación con otros eventos estresantes, mientras que se observó un patrón opuesto en América del Norte. Conclusiones: El impacto de los estresores asociados a la COVID-19 sobre la salud mental abarca un amplio rango de síntomas y es más severo que otros eventos estresantes. Esta diferencia fue especialmente evidente en Latinoamérica. Estos hallazgos enfatizan la necesidad de un tamizaje global para detectar una amplia gama de problemas de salud mental como parte de un enfoque de salud pública, permitiendo programas específicos de prevención e intervención.

Symptom networks of COVID-19-related versus other potentially traumatic events in a global sample.

The potential mental health consequences of the coronavirus disease 2019 (COVID-19) pandemic are widely acknowledged; however, limited research exists regarding the nature and patterns of stress responses to COVID-19-related potentially traumatic events (PTEs) and the convergence/divergence with responses to other (non-COVID-19-related) PTEs. Network analysis can provide a useful method for evaluating and comparing these symptom structures. The present study includes 7034 participants from 86 countries who reported on mental health symptoms associated with either a COVID-19-related PTE (n = 1838) or other PTE (n = 5196). Using network analysis, we compared the centrality and connections of symptoms within and between each group. Overall, results show that the COVID-19-related network includes transdiagnostic symptom associations similar to networks tied to PTEs unrelated to the pandemic. Findings provide evidence for a shared centrality of depression across networks and theoretically consistent connections between symptoms. Network differences included stronger connections between avoidance-derealization and hypervigilance-depression in the COVID-19 network. Present findings support the conceptualization of psychological responses to pandemic-related PTEs as a network of highly interconnected symptoms and support the use of a transdiagnostic approach to the assessment and treatment of mental health challenges related to the COVID-19 pandemic.

Fruit scent and observer colour vision shape food-selection strategies in wild capuchin monkeys.

The senses play critical roles in helping animals evaluate foods, including fruits that can change both in colour and scent during ripening to attract frugivores. Although numerous studies have assessed the impact of colour on fruit selection, comparatively little is known about fruit scent and how olfactory and visual data are integrated during foraging. We combine 25 months of behavioural data on 75 wild, white-faced capuchins (Cebus imitator) with measurements of fruit colours and scents from 18 dietary plant species. We show that frequency of fruit-directed olfactory behaviour is positively correlated with increases in the volume of fruit odours produced during ripening. Monkeys with red-green colour blindness sniffed fruits more often, indicating that increased reliance on olfaction is a behavioural strategy that mitigates decreased capacity to detect red-green colour contrast. These results demonstrate a complex interaction among fruit traits, sensory capacities and foraging strategies, which help explain variation in primate behaviour.

Comparing Amazon Mechanical Turk with unpaid internet resources in online clinical trials.

Internet interventions face significant challenges in recruitment and attrition rates are typically high and problematic. Finding innovative yet scientifically valid avenues for attaining and retaining participants is therefore of considerable importance. The main goal of this study was to compare recruitment process and participants characteristics between two similar randomized control trials of mood management interventions. One of the trials (Bunge et al., 2016) was conducted with participants recruited from Amazon's Mechanical Turk (AMT), and the other trial recruited via Unpaid Internet Resources (UIR). METHODS: The AMT sample (Bunge et al., 2016) consisted of 765 adults, and the UIR sample (recruited specifically for this study) consisted of 329 adult US residents. Participants' levels of depression, anxiety, confidence, motivation, and perceived usefulness of the intervention were assessed. The AMT sample was financially compensated whereas the UIR was not. RESULTS: AMT yielded higher recruitment rates per month (p < .05). At baseline, the AMT sample reported significantly lower depression and anxiety scores (p < .001 and p < .005, respectively) and significantly higher mood, motivation, and confidence (all p < .001) compared to the UIR sample. AMT participants spent significantly less time on the site (p < .05) and were more likely to complete follow-ups than the UIR sample (p < .05). Both samples reported a significant increase in their level of confidence and motivation from pre- to post-intervention. AMT participants showed a significant increase in perceived usefulness of the intervention (p < .0001), whereas the UIR sample did not (p = .1642). CONCLUSIONS: By using AMT, researchers can recruit very rapidly and obtain higher retention rates; however, these participants may not be representative of the general online population interested in clinical interventions. Considering that AMT and UIR participants differed in most baseline variables, data from clinical studies resulting from AMT samples should be interpreted with caution.

Mood management effects of brief unsupported internet interventions.

BACKGROUND: Most users of unsupported Internet interventions visit that site only once, therefore there is a need to create interventions that can be offered as a single brief interaction with the user. OBJECTIVE: The main goal of this study was to compare the effect of a one-session unsupported Internet intervention on participants' clinical symptoms (depressive and anxiety symptoms) and related variables (mood, confidence and motivation). METHOD: A total of 765 adults residing in the United States took part in a randomized controlled trial. Participants were randomly assigned to one of five brief plain text interventions lasting 5-10 min. The interventions designed to address depressive symptoms were: thoughts (increasing helpful thoughts), activities (increasing activity level), sleep hygiene, assertiveness (increasing assertiveness awareness), Own Methods (utilizing methods that were previously successful). They were followed-up one week after consenting. RESULTS: A main effect of time was observed for both depression (F(1, 563) = 234.70, p < 0.001) and anxiety (F(1, 551) = 170.27, p < 0.001). In all cases, regardless of assigned condition and Major Depressive Episode status, mean scores on both positive outcomes (mood, confidence and motivation) and negative outcome scores (depression and anxiety) improved over time. CONCLUSIONS: Brief unsupported Internet interventions can improve depressive symptoms at one-week follow-up. Further outcome data and research implications will be discussed.