The role of environmental sensitivity in the mental health of Syrian refugee children: a multi-level analysis.

Individuals with high environmental sensitivity have nervous systems that are disproportionately receptive to both the protective and imperilling aspects of the environment, suggesting their mental health is strongly context-dependent. However, there have been few consolidated attempts to examine putative markers of sensitivity, across different levels of analysis, within a single cohort of individuals with high-priority mental health needs. Here, we examine psychological (self-report), physiological (hair hormones) and genetic (polygenic scores) markers of sensitivity in a large cohort of 1591 Syrian refugee children across two waves of data. Child-caregiver dyads were recruited from informal tented settlements in Lebanon, and completed a battery of psychological instruments at baseline and follow-up (12 months apart). Univariate and multivariate Bayesian linear mixed models were used to examine a) the interrelationships between markers of sensitivity and b) the ability of sensitivity markers to predict anxiety, depression, post-traumatic stress disorder, and externalising behaviour. Self-reported sensitivity (using the Highly Sensitive Child Scale) significantly predicted a higher burden of all forms of mental illness across both waves, however, there were no significant cross-lagged pathways. Physiological and genetic markers were not stably predictive of self-reported sensitivity, and failed to similarly predict mental health outcomes. The measurement of environmental sensitivity may have significant implications for identifying and treating mental illness, especially amongst vulnerable populations, but clinical utility is currently limited to self-report assessment.

War exposure, post-traumatic stress symptoms and hair cortisol concentrations in Syrian refugee children.

Altered secretion of cortisol, the primary effector of the hypothalamus-pituitary-adrenal axis, has been proposed as a means by which traumatic experiences compromise later mental health. However, despite the popularity of cortisol as a potential biomarker for stress and adversity, findings are inconsistent, and little is known about the impact of war-related trauma on stress physiology of children and adolescents. Here we aimed to evaluate the relationships between war exposure, current living conditions, hair cortisol concentrations (HCC) and post-traumatic stress disorder (PTSD) symptoms in a large cohort of Syrian refugee children and adolescents (6-18 years) and their caregiver. This longitudinal observational study assessed Syrian refugee children and adolescents in two waves, 1 year apart, within informal tented settlements in Lebanon. The relationships between war exposure, time since leaving Syria, PTSD symptoms and HCC were investigated using linear mixed-model regression utilising both waves of data collected (Y1: N = 1574, Y2: N = 923). Hair cortisol concentration was positively, but weakly associated with the number of war-related events experienced. This was limited to those who were at least 12 years old at the time of war exposure. Conversely, HCC decreased with time since leaving Syria. HCC was also associated with PTSD symptoms but not with the quality of their current living conditions. This study revealed that changes to hypothalamic-pituitary-adrenal axis activity may accompany both earlier war exposure and current PTSD symptoms in children and adolescents. Additionally, early adolescence may be a particularly sensitive time in terms of trauma-related changes to the hypothalamic-pituitary-adrenal axis.

A Bayesian approach for exploring person × environment interaction within the environmental sensitivity meta-framework.

BACKGROUND: For investigating the individual-environment interplay and individual differences in response to environmental exposures as captured by models of environmental sensitivity including Diathesis-stress, Differential Susceptibility, and Vantage Sensitivity, over the last few years, a series of statistical guidelines have been proposed. However, available solutions suffer of computational problems especially relevant when sample size is not sufficiently large, a common condition in observational and clinical studies. METHOD: In the current contribution, we propose a Bayesian solution for estimating interaction parameters via Monte Carlo Markov Chains (MCMC), adapting Widaman et al. (Psychological Methods, 17, 2012, 615) Nonlinear Least Squares (NLS) approach. RESULTS: Findings from an applied exemplification and a simulation study showed that with relatively big samples both MCMC and NLS estimates converged on the same results. Conversely, MCMC clearly outperformed NLS, resolving estimation problems and providing more accurate estimates, particularly with small samples and greater residual variance. CONCLUSIONS: As the body of research exploring the interplay between individual and environmental variables grows, enabling predictions regarding the form of interaction and the extent of effects, the Bayesian approach could emerge as a feasible and readily applicable solution to numerous computational challenges inherent in existing frequentist methods. This approach holds promise for enhancing the trustworthiness of research outcomes, thereby impacting clinical and applied understanding.

Moderate cardiac vagal tone predicts more cooperation in highly sensitive individuals.

Cooperation, as a mutual collaboration, is a defining feature of human social life. Individual characteristics can influence cooperation. Recent studies have shown a quadratic relationship between cardiac vagal tone (CVT), an index of self-regulation, and prosocial behaviors. Individual differences in cooperation might also vary as a function of people's environmental sensitivity (ES), i.e., may be influenced by individual differences in the perception and processing of inner and external stimuli. We tested the direct and interactive effect of CVT and ES on cooperative behaviors in two independent samples. We measured heart rate and engagement in cooperative acts in 80 young adults (M = 23.61; SD = 1.60) who were also asked to self-report on ES. We found an inverted-U relationship between CVT and cooperative behaviors. ES, on the other hand, did not predict differences in cooperative behaviors but moderated the relationships between CVT and cooperation, although the magnitude of this result was small. Specifically, only among individuals with higher ES cooperative behaviors change as a function of CVT. Highly sensitive individuals with lower or higher CVT, were less cooperative than low sensitive ones. Subsequently, we replicated the same study design in a second sample of 88 undergraduate students (M = 23.69; SD = 4.91). Once again, we found evidence supporting the presence of an inverted-U relationship between CVT and cooperative behaviors, and we also found that ES moderated the relationships between the quadratic CVT term and cooperation.

The important role of mothers during displacement: Direct and indirect effects of the refugee context on Syrian refugee children's mental health.

Refugee children are at increased risk for mental health problems, including post-traumatic stress, depression, and externalizing problems. The refugee environment, maternal mental health, and parenting may reduce or exacerbate that risk. This study investigated their direct and indirect associations with child mental health cross-sectionally in a sample of Syrian refugee child-mother dyads in Lebanon in 2017-19. Mediating pathways were tested using structural equation modeling with 1446 dyads (child: Mage = 11.39, 52.1% females) and again 1 year later with 872 (child: Mage = 12.17, 53.1% females) of the original sample. Mediating pathways from the refugee environment through maternal mental health and parenting to child outcomes were detected, emphasizing the importance of a holistic approach to refugee mental health.

Beyond developmental psychopathology: Positive child development.

The field of developmental psychopathology has made significant contributions to our understanding of both typical and atypical development. However, while there are established theories for developmental psychopathology with detailed criteria for pathological outcomes, there is less agreement regarding development under optimal conditions and the definition of positive outcomes. In this conceptual paper, I make the case that a better understanding of positive child development is crucial because it will not only advance our general knowledge on human development but also complement current work on developmental psychopathology. After defining positive development as the development of positive functioning in children, such as skills, strengths, competencies, and wellbeing, rather than the absence of problems, current concepts with relevance for positive development are reviewed, before highlighting gaps in our knowledge on positive development and suggestions for future research. Although several of the reviewed frameworks provide important contributions to the conceptualization of positive development, most of them focus on positive functioning in adults with limited consideration of development in the early years. More research is needed that specifically targets the development of positive outcomes from early childhood onward in order to develop a more comprehensive and holistic theory of positive child development.

The role of environmental sensitivity in post-traumatic stress symptoms in Lebanese children and adolescents.

Children differ substantially in their sensitivity to the quality of their environment. Some are more sensitive and more likely to develop Post-Traumatic Stress Disorder (PTSD) in response to Childhood Adversities (CAs), but might also benefit more from Positive Home Experiences (PHE). The aim of this study is to investigate the role of Environmental Sensitivity (ES), CAs and PHEs in PTSD development in children and adolescents. Data was collected from N = 2,569 children/adolescents. PTSD symptoms, CAs, PHEs and ES were assessed with self-report measures. We found that higher ES and CAs emerged as risk factors for PTSD development whereas higher levels of PHEs protected against PTSD. ES moderated the effects of CAs (ß = 1.08, p < .001) on PTSD symptoms in the total sample. This moderating effect was more pronounced in girls, suggesting that highly sensitive girls with high childhood adversities were more likely to have higher PTSD symptoms than girls with low levels of sensitivity (ß = 1.09, p < .001). In conclusion, Environmental Sensitivity played an important role as a risk factor for PTSD and as a moderating factor that accentuated the main effects of childhood adversities, particularly in girls.

Predictors of psychological risk and resilience among Syrian refugee children.

OBJECTIVES: War-exposed refugee children are at elevated risk for mental health problems, but a notable proportion appear resilient. We aimed to investigate the proportion of Syrian refugee children who can be considered resilient, and applied a novel approach to identify factors predicting individual differences in mental health outcomes following war exposure. METHODS: The sample included 1,528 war-exposed Syrian refugee children and their primary caregiver living in refugee settlements in Lebanon. Children were classed as having low symptoms (LS) if they scored below clinically validated cut-offs for post-traumatic stress disorder (PTSD), depression and externalising behaviour problems. Children scoring above any cut-off were classified as having high symptoms (HS). Each LS child was matched with one HS who reported similar war exposure, to test what differentiates children with similar exposures but different outcomes. RESULTS: 19.3% of the children met our resilience criteria and were considered LS. At the individual level, protective traits (e.g. self-esteem; OR = 1.51, 95% CI [1.25, 1.81]) predicted LS classification, while environmental sensitivity (OR = 0.69, 95% CI [0.59, 0.82]), poorer general health (OR = 0.71, 95% CI [0.58, 0.87]) and specific coping strategies (e.g. avoidance; OR = 0.90, 95% CI [0.85, 0.96]) predicted HS classification. Social/environmental predictors included perceived social support (OR = 1.23, 95% CI [1.02, 1.49]), loneliness and social isolation (OR = 0.85, 95% CI [0.80, 0.90]), child maltreatment (OR = 0.96, 95% CI [0.94, 0.97]), and caregiver mental and general health (e.g. caregiver depression; OR = 0.94, 95% CI [0.92, 0.97]). CONCLUSIONS: Future research should take multiple dimensions of functioning into account when defining risk for mental health problems and consider the identified predictors as potential targets for interventions.

Strengthening parental self-efficacy and resilience: A within-subject experimental study with refugee parents of adolescents.

Post-migration stress and parenting adolescents can reduce parental self-efficacy. This study tested the effects of strengthening parental self-efficacy in refugee parents of adolescents and whether this makes parental self-efficacy less impacted by post-migration stressors. Using a within-subject experimental design, experience sampling data were collected in 2019 from 53 refugee parents of adolescents (Mage  = 39.7, SDage  = 5.59, 73% Syrian, 70% mothers) in the Netherlands. Data were analyzed by dynamic structural equation modeling using interrupted time-series analysis. The single-session personalized intervention strengthened parental self-efficacy (small effect: between case standardized mean difference = 0.09) and made refugee parents less vulnerable to post-migration stressors. Findings suggest that parental self-efficacy is malleable and strengthening it fosters refugee parents' resilience. Replications with longer-term follow-ups are needed.

The interplay between parenting and environmental sensitivity in the prediction of children's externalizing and internalizing behaviors during COVID-19.

The interplay of parenting and environmental sensitivity on children's behavioral adjustment during, and immediately after, the COVID-19 lockdown restrictions was investigated in two longitudinal studies involving Italian preschoolers (Study 1, N = 72; 43% girls, Myears = 3.82(1.38)) and primary school children (Study 2, N = 94; 55% girls, Myears = 9.08(0.56)). Data were collected before and during the first-wave lockdown (Studies 1 and 2) and one month later (Study 1). Parental stress and parent-child closeness were measured. Markers of environmental sensitivity in children were temperamental fearfulness and Sensory Processing Sensitivity. Results showed little change in externalizing and internalizing behaviors over time, but differences emerged when considering parenting and children's environmental sensitivity. In preschoolers, greater parenting stress was related to a stronger increase in internalizing and externalizing behaviors, with children high in fearful temperament showing a more marked decrease in externalizing behaviors when parenting stress was low. In school-aged children, parent-child closeness emerged as a protective factor for internalizing and externalizing behaviors during COVID-19, with children high in Sensory Processing Sensitivity showing a marked decrease in internalizing behaviors when closeness was high. Implications for developmental theory and practice in times of pandemic are discussed.

Risk and resilience in Syrian refugee children: A multisystem analysis.

Refugee children are often exposed to substantial trauma, placing them at increased risk for mental illness. However, this risk can be mitigated by a capacity for resilience, conferred from multiple ecological systems (e.g., family, community), including at an individual biological level. We examined the ability of hair cortisol concentrations and polygenic scores for mental health to predict risk and resilience in a sample of Syrian refugee children (n = 1359). Children were categorized as either at-risk or resilient depending on clinical thresholds for posttraumatic stress disorder, depression, and externalizing behavior problems. Logistic regression was used to examine main and interacting effects while controlling for covariates. Elevated hair cortisol concentrations were significantly associated with reduced resilience (odds ratio (OR)=0.58, 95%CI [0.40, 0.83]) while controlling for levels of war exposure. Polygenic scores for depression, self-harm, and neuroticism were not found to have any significant main effects. However, a significant interaction emerged between hair cortisol and polygenic scores for depression (OR=0.04, 95%CI [0.003 0.47]), suggesting that children predisposed to depression were more at risk for mental health problems when hair cortisol concentrations were high. Our results suggest that biomarkers (separately and in combination) might support early identification of refugee children at risk for mental health problems.

Genetic architecture of Environmental Sensitivity reflects multiple heritable components: a twin study with adolescents.

Humans differ substantially in how strongly they respond to similar experiences. Theory suggests that such individual differences in susceptibility to environmental influences have a genetic basis. The present study investigated the genetic architecture of Environmental Sensitivity (ES) by estimating its heritability, exploring the presence of multiple heritable components and its genetic overlap with common personality traits. ES was measured with the Highly Sensitive Child (HSC) questionnaire and heritability estimates were obtained using classic twin design methodology in a sample of 2868 adolescent twins. Results indicate that the heritability of sensitivity was 0.47, and that the genetic influences underlying sensitivity to negative experiences are relatively distinct from sensitivity to more positive aspects of the environment, supporting a multi-dimensional genetic model of ES. The correlation between sensitivity, neuroticism and extraversion was largely explained by shared genetic influences, with differences between these traits mainly attributed to unique environmental influences operating on each trait.

Polygenic scores for schizophrenia and major depression are associated with psychosocial risk factors in children: evidence of gene-environment correlation.

BACKGROUND: Whilst genetic and environmental risk factors for schizophrenia (SCZ) and major depressive disorder (MDD) have been established, it is unclear whether exposure to environmental risk factors is genetically confounded by passive, evocative or active gene-environment correlation (rGE). STUDY OBJECTIVE: This study aims to investigate: (a) whether the genetic risk for SCZ/MDD in children is correlated with established environmental and psychosocial risk factors in two British community samples, the 1958 National Child Development Study (NCDS) and the Millennium Cohort Study (MCS), (b) whether these associations vary between both psychopathologies, and (c) whether findings differ across the two cohorts which were born 42 years apart. METHODS: Polygenic risk scores (PRS) from existing large genome-wide associations studies (GWAS) were applied to test the correlation between the child genetic risk for SCZ/MDD and known environmental risk factors. In addition, parental and child genetic data from MCS were used to distinguish between passive and evocative rGE. RESULTS: The child polygenic risk for SCZ and MDD was correlated with single parenthood in MCS. Moreover, the lack of father's involvement in child care was associated with the genetic risk for SCZ in NCDS. However, we also found associations between several indicators of low socioeconomic status and heightened genetic risk for MDD in children in both cohorts. Further, the genetic risk for MDD was associated with parental lack of interest in the child's education in NCDS as well as more maternal smoking and less maternal alcohol consumption during childhood in MCS. According to sensitivity analyses in MCS (controlling for parental genotype), more than half of our significant correlations reflected passive rGE. CONCLUSIONS: Findings suggest that several established environmental and psychosocial risk factors for SCZ and MDD are at least partially associated with children's genetic risk for these psychiatric disorders.

Individual differences in sensitivity to the early environment as a function of amygdala and hippocampus volumes: An exploratory analysis in 12-year-old boys.

Children differ in their response to environmental exposures, with some being more sensitive to contextual factors than others. According to theory, such variability is the result of individual differences in neurobiological sensitivity to environmental features, with some individuals generally more affected by both negative and/or positive experiences. In this exploratory study we tested whether left and right amygdala and hippocampus volumes (corrected for total brain size) account for individual differences in response to environmental influences in a sample of 62 boys. Cumulative general environmental quality, ranging from low to high, was measured across the first 9 years and child behavior was reported by teachers when boys were 12-13 years old. According to analyses, only the left amygdala volume - not any of the other brain volumes - emerged as an important brain region for sensitivity to positive environmental aspects. Boys with a larger left amygdala benefited significantly more from higher environmental quality than boys with a smaller left amygdala whilst not being more vulnerable to lower quality. Besides providing preliminary evidence for differences in environmental sensitivity due to brain structure, the results also point to the left amygdala as having a specific role regarding the response to environmental influences.

Investigating sensitivity through the lens of parents: validation of the parent-report version of the Highly Sensitive Child scale.

Children differ in their environmental sensitivity (ES), which can be measured observationally or by self-report questionnaire. A parent-report scale represents an important tool for investigating ES in younger children but has to be psychometrically robust and valid. In the current multistudy, we validated the parent-report version of the Highly Sensitive Child (HSC-PR) scale in Italian children, evaluating its factorial structure (Study 1, N = 1,857, 6.2 years, age range: 2.6-14 years) through a multigroup Confirmatory Factory Analysis in preschoolers (n = 1,066, 4.2 years) and school-age children (n = 791, 8.8 years). We then investigated the HSC-PR relationship with established temperament traits (Study 2, N = 327, 4.3 years), before exploring whether the scale moderates the effects of parenting stress on children's emotion regulation (Study 3, N = 112, 6.5 years). We found support for a bi-factor structure in both groups, though in preschoolers minor adaptations were suggested for one item. Importantly, the HSC-PR did not fully overlap with common temperament traits and moderated the effects of parenting stress on children emotion regulation. To conclude, the HSC-PR performs well and appears to capture ES in children.

Cohort profile: biological pathways of risk and resilience in Syrian refugee children (BIOPATH).

The BIOPATH cohort was established to explore the interplay of psychosocial and biological factors in the development of resilience and mental health problems in Syrian refugee children. Based in Lebanon, a middle-income country significantly impacted by the refugee crisis, it is the first such cohort of refugees in the Middle East. Families were recruited from informal tented settlements in the Beqaa region using purposive cluster sampling. At baseline (October 2017-January 2018), N = 3188 individuals participated [n = 1594 child-caregiver dyads; child gender, 52.6% female; mean (SD) age = 11.44 (2.44) years, range = 6-19]. Re-participation rate at 1-year follow-up was 62.8%. Individual interviews were conducted with children and primary caregivers and biological samples collected from children. Measures include: (1) children's well-being and mental health problems (using tools validated against clinical interviews in a subsample of the cohort); (2) psychosocial risk and protective factors at the level of the individual (e.g. coping strategies), family (e.g. parent-child relationship), community (e.g. collective efficacy), and wider context (e.g. services); (3) saliva samples for genetic and epigenetic (methylation) analyses; (4) hair samples to measure cortisol, dehydroepiandrosterone (DHEA) and testosterone. This cohort profile provides details about sampling and recruitment, data collection and measures, demographic data, attrition and potential bias, key findings on resilience and mental health problems in children and strengths and limitations of the cohort. Researchers interested in accessing data should contact Professor Michael Pluess at Queen Mary University of London, UK (e-mail: m.pluess@qmul.ac.uk).

The role of environmental sensitivity in the development of rumination and depressive symptoms in childhood: a longitudinal study.

Some children are more affected than others by their upbringing due to their increased sensitivity to the environment. More sensitive children are at heightened risk for the development of internalizing problems, particularly when experiencing unsupportive parenting. However, little is known about how the interplay between children's sensitivity and parenting leads to higher levels of depressive symptoms. In the current study, we investigated the interaction between early parenting and children's sensitivity on levels of depressive symptomatology in middle childhood, exploring the role of rumination as a possible mediator in a community sample. Participants included 196 USA resident families, from a middle class and mostly European-American background, and their healthy children, followed up from age 3 until 9 and 12 years. Environmental sensitivity was assessed observationally when children were 3 years old. Parenting style was based on parent-report at the age of 3 years. When children were nine, they completed questionnaires on rumination and depressive symptoms (repeated at 12 years). Analyses were run applying a Bayesian approach. Children's sensitivity interacted with permissive parenting in predicting rumination at age 9. Rumination, in turn, was associated with depressive symptoms at age 9 and, to a lesser extent, at age 12. No relevant interactions emerged for authoritative and authoritarian parenting. Sensitive children may be at heightened risk for internalizing problems when exposed to a permissive parenting style. Permissive parenting was associated with increased ruminative coping strategies in sensitive children which, in turn, predicted higher levels of depression. Hence, rumination emerged as an important cognitive risk factor for the development of depressive symptoms in sensitive children.

Promoting well-being in refugee children: An exploratory controlled trial of a positive psychology intervention delivered in Greek refugee camps.

Rigorously evaluated interventions that target protective factors and positive resources rather than ameliorating negative outcomes in child refugees are rare. To address this, we developed and evaluated a short, group-based resilience-building intervention called Strengths for the Journey (SFJ), which was designed for war-affected children. We conducted a quasi-randomized pilot study of the SFJ intervention with 72 7- to 14-year-old forcibly displaced children (Mage = 10.76, 64.8% female) in three refugee camps in Lesvos, Greece. Intervention effectiveness was assessed by measuring pre-post changes in well-being, self-esteem, optimism, and depressive symptoms from before (T1) to immediately after the intervention/wait-list task (T2). Four focus group interviews were conducted with 31 of the participants to discuss their views on the effects of the intervention and the continued use of the skills that were learned. Using repeated-measures ANOVAs, we found improvements in well-being, F (1, 46) = 42.99, ηp2 = .48, self-esteem, F (1, 56) = 29.11, ηp2 = .40, optimism, F (1, 53) = 27.16, ηp2 = .34, and depressive symptoms, F (1, 31) = 62.14, ηp2 = .67, in the intervention group compared with the wait-listed group (p < .05). Focus group participants highlighted the importance of SFJ in developing a sense of togetherness and building their strengths. Child refugees in low-resource settings may benefit from brief, first-line interventions that target protective factors such as well-being, hope, self-esteem, and belonging.

Gene-environment interaction and psychiatric disorders: Review and future directions.

Empirical studies suggest that psychiatric disorders result from a complex interplay between genetic and environmental factors. Most evidence for such gene-environment interaction (GxE) is based on single candidate gene studies conducted from a Diathesis-Stress perspective. Recognizing the short-comings of candidate gene studies, GxE research has begun to focus on genome-wide and polygenic approaches as well as drawing on different theoretical concepts underlying GxE, such as Differential Susceptibility. After reviewing evidence from candidate GxE studies and presenting alternative theoretical frameworks underpinning GxE research, more recent approaches and findings from whole genome approaches are presented. Finally, we suggest how future GxE studies may unpick the complex interplay between genes and environments in psychiatric disorders.

Distinguishing differential susceptibility, diathesis-stress, and vantage sensitivity: Beyond the single gene and environment model.

Currently, two main approaches exist to distinguish differential susceptibility from diathesis-stress and vantage sensitivity in Genotype × Environment interaction (G × E) research: regions of significance (RoS) and competitive-confirmatory approaches. Each is limited by its single-gene/single-environment foci given that most phenotypes are the product of multiple interacting genetic and environmental factors. We thus addressed these two concerns in a recently developed R package (LEGIT) for constructing G × E interaction models with latent genetic and environmental scores using alternating optimization. Herein we test, by means of computer simulation, diverse G × E models in the context of both single and multiple genes and environments. Results indicate that the RoS and competitive-confirmatory approaches were highly accurate when the sample size was large, whereas the latter performed better in small samples and for small effect sizes. The competitive-confirmatory approach generally had good accuracy (a) when effect size was moderate and N ≥ 500 and (b) when effect size was large and N ≥ 250, whereas RoS performed poorly. Computational tools to determine the type of G × E of multiple genes and environments are provided as extensions in our LEGIT R package.