Social supports moderate the effects of child adversity on neural correlates of threat processing

Adverse Life Experiences and Brain Function: A Meta-Analysis of Functional Magnetic Resonance Imaging Findings

Importance

Adverse life experiences have been proposed to contribute to diverse mental health problems through an association with corticolimbic functioning. Despite compelling evidence from animal models, findings from studies in humans have been mixed; activation likelihood estimation (ALE) meta-analyses have failed to identify a consistent association of adverse events with brain function.

Objective

To investigate the association of adversity exposure with altered brain reactivity using multilevel kernel density analyses (MKDA), a meta-analytic approach considered more robust than ALE to small sample sizes and methodological differences between studies.

Data Sources

Searches were conducted using PsycInfo, Medline, EMBASE, and Web of Science from inception through May 4, 2022. The following search term combinations were used for each database: trauma, posttraumatic stress disorder (PTSD), abuse, maltreatment, poverty, adversity, or stress; and functional magnetic resonance imaging (fMRI) or neuroimaging; and emotion, emotion regulation, memory, memory processing, inhibitory control, executive functioning, reward, or reward processing.

Study Selection

Task-based fMRI studies within 4 domains (emotion processing, memory processing, inhibitory control, and reward processing) that included a measure of adverse life experiences and whole-brain coordinate results reported in Talairach or Montreal Neurological Institute space were included. Conference abstracts, books, reviews, meta-analyses, opinions, animal studies, articles not in English, and studies with fewer than 5 participants were excluded.

Data Extraction and Synthesis

Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting guideline, 2 independent reviewers assessed abstracts and full-text articles for entry criteria. A third reviewer resolved conflicts and errors in data extraction. Data were pooled using a random-effects model and data analysis occurred from August to November 2022.

Main Outcomes and Measures

Peak activation x-axis (left-right), y-axis (posterior-anterior), and z-axis (inferior-superior) coordinates were extracted from all studies and submitted to MKDA meta-analyses.

Results

A total of 83 fMRI studies were included in the meta-analysis, yielding a combined sample of 5242 participants and 801 coordinates. Adversity exposure was associated with higher amygdala reactivity (familywise error rate corrected at P < .001; x-axis = 22; y-axis = -4; z-axis = -17) and lower prefrontal cortical reactivity (familywise error rate corrected at P < .001; x-axis = 10; y-axis = 60; z-axis = 10) across a range of task domains. These altered responses were only observed in studies that used adult participants and were clearest among those who had been exposed to severe threat and trauma.

Conclusions and Relevance

In this meta-analysis of fMRI studies of adversity exposure and brain function, prior adversity exposure was associated with altered adult brain reactivity to diverse challenges. These results might better identify how adversity diminishes the ability to cope with later stressors and produces enduring susceptibility to mental health problems.

Association between childhood trauma and affective lability among adolescents: A moderated mediation model

BACKGROUND

Affective lability is an important feature of psychopathology. However, there is limited relevant research involving adolescents. To fill this research gap, the present study assessed the relationship between childhood trauma and affective lability among adolescents using a moderated mediation model.

METHODS

A total of 3738 students were recruited from four high schools in Shenzhen, China, between September and December 2019. The participants completed self-reported questionnaires measuring childhood trauma, affective lability, body image dissatisfaction, and the experience of being bullied. Linear regression and moderated mediation analyses were used in this study.

RESULTS

Linear regression analysis showed that emotional abuse and body image dissatisfaction positively predicted affective lability in boys and girls (all p < 0.001). Body image dissatisfaction mediated the relationship between emotional abuse and affective lability. In the moderated mediation model, being bullied moderated the direct path from emotional abuse to affective lability (p = 0.0236, p = 0.0188), and gender did not have a significant moderating effect on any direct or indirect path (all p > 0.05).

LIMITATIONS

A causal relationship could not be ascertained due to the cross-sectional design, and the results cannot be generalized to other populations.

CONCLUSIONS

The findings support that childhood trauma has an impact on affective lability in adolescents. Specifically, body image dissatisfaction and being bullied affect the relationship between emotional abuse and affective lability.

Amygdala responses to threat in violence-exposed children depend on trauma context and maternal caregiving

Early life adversity (ELA) has been linked with increased arousal responses to threat, including increased amygdala reactivity. Effects of ELA on brain function are well recognized, and emerging evidence suggests that caregivers may influence how environmental stressors impact children's brain function. We investigated the hypothesis that positive interaction between mother and child can buffer against ELA effects on children's neural responses to threat, and related symptoms. N = 53 mother-child pairs (children ages 8-14 years) were recruited from an urban population at high risk for violence exposure. Maternal caregiving was measured using the Parenting Questionnaire and in a cooperation challenge task. Children viewed fearful and neutral face stimuli during functional magnetic resonance imaging. Children who experienced greater violence at home showed amygdala sensitization, whereas children experiencing more school and community violence showed amygdala habituation. Sensitization was in turn linked with externalizing symptoms. However, maternal warmth was associated with a normalization of amygdala sensitization in children, and fewer externalizing behaviors prospectively up to 1 year later. Findings suggested that the effects of violence exposure on threat-related neural circuitry depend on trauma context (inside or outside the home) and that primary caregivers can increase resilience.

Conceptualizing psychological resilience through resting-state functional MRI in a mentally healthy population: a systematic review

Conceptualizations and operational definitions of psychological resilience vary across resilience neuroimaging studies. Data on the neural features of resilience among healthy individuals has been scarce. Furthermore, findings from resting-state functional magnetic resonance imaging (fMRI) studies were inconsistent across studies. This systematic review summarized resting-state fMRI findings in different modalities from various operationally defined resilience in a mentally healthy population. The PubMed and MEDLINE databases were searched. Articles that focused on resting-state fMRI in relation to resilience, and published before 2022, were targeted. Orbitofrontal cortex, anterior cingulate cortex, insula and amygdala, were reported the most from the 19 included studies. Regions in emotional network was reported the most from the included studies. The involvement of regions like amygdala and orbitofrontal cortex indicated the relationships between emotional processing and resilience. No common brain regions or neural pathways were identified across studies. The emotional network appears to be studied the most in association with resilience. Matching fMRI modalities and operational definitions of resilience across studies are essential for meta-analysis.

Childhood adversity and late-life depression: moderated mediation model of stress and social support

Background

As life expectancy increases, understanding the mechanism for late-life depression and finding a crucial moderator becomes more important for mental health in older adults. Childhood adversity increases the risk of clinical depression even in old age. Based on the stress sensitivity theory and stress-buffering effects, stress would be a significant mediator, while social support can be a key moderator in the mediation pathways. However, few studies have tested this moderated mediation model with a sample of older adults. This study aims to reveal the association between childhood adversity and late-life depression in older adults, taking into consideration the effects of stress and social support.

Methods

This study used several path models to analyze the data from 622 elderly participants who were never diagnosed with clinical depression.

Results

We found that childhood adversity increases the odds ratio of depression by approximately 20% in older adults. Path model with mediation demonstrates that stress fully mediates the pathway from childhood adversity to late-life depression. Path model with moderated mediation also illustrates that social support significantly weakens the association between childhood adversity and perceived stress.

Conclusion

This study provides empirical evidence to reveal a more detailed mechanism for late-life depression. Specifically, this study identifies one crucial risk factor and one protective factor, stress and social support, respectively. This brings insight into prevention of late-life depression among those who have experienced childhood adversity.

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

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

Functional imaging correlates of childhood trauma: A qualitative review of past research and emerging trends

Childhood trauma exposure is common and is associated with poor clinical outcomes in adolescence along with mental health and sociodemographic challenges in adulthood. While many strategies exist to investigate the biological imprint of childhood trauma exposure, functional neuroimaging is a robust and growing technology for non-invasive studies of brain activity following traumatic experience and the relationship of childhood trauma exposure with psychopathology, cognition, and behavior. In this review, we discuss three popular approaches for discerning functional neural correlates to early life trauma, including regional activation, bivariate functional connectivity, and network-based connectivity. The breadth of research in each method is discussed, followed by important limitations and considerations for future research. We close by considering emerging trends in functional neuroimaging research of childhood trauma, including the use of complex decision-making tasks to mimic clinically-relevant behaviors, data-driven techniques such as multivariate pattern analysis and whole-brain network topology, and the applications of real-time neurofeedback for treatment of trauma-related mental disorders. We aim for this review to provide a framework for understanding the relationship between atypical neural functioning and adverse outcomes following childhood trauma exposure, with a focus on improving consistency in research methods and translatability of research findings for clinical settings.

Resilience and young people's brain structure, function and connectivity: A systematic review

Although negative early life experiences are associated with an increased risk of developing psychopathology, some individuals exposed to childhood adversity demonstrate psychological resilience. Little is known about the neural correlates of resilience, especially in young people. To address this gap, we conducted a systematic review of neuroimaging studies of resilience in youth. The PubMed, Web of Science, Scopus, and PsycINFO databases were searched; 5,482 studies were identified. Following title/abstract screening, and full reading of the remaining articles, 22 studies based on 19 unique datasets were included. We found preliminary evidence that resilience is associated with structural, functional, and connectivity differences in young people, as assessed using structural and functional MRI and diffusion tensor imaging methods. Despite heterogeneity in definitions/assessment of resilience and a limited number of studies, the neuroimaging literature suggests some convergence across modalities regarding brain regions linked to resilience (especially the prefrontal cortex). Future studies would benefit from adopting longitudinal designs, broader conceptualisations of resilience that capture the impact of adversity exposure, and a dimensional approach to psychopathology.

Posttraumatic Stress Disorder and the Developing Adolescent Brain

Posttraumatic stress disorder (PTSD) in adolescents is common and debilitating. In contrast to adult PTSD, relatively little is known about the neurobiology of adolescent PTSD, nor about how current treatments may alter adolescent neurodevelopment to allow recovery from PTSD. Improving our understanding of biological mechanisms of adolescent PTSD, taken in the context of neurodevelopment, is crucial for developing novel and personalized treatment approaches. In this review, we highlight prevailing constructs of PTSD and current findings on these domains in adolescent PTSD. Notably, little data exist in adolescent PTSD for prominent adult PTSD constructs, including threat learning and attentional threat bias. Most work to date has examined general threat processing, emotion regulation, and their neural substrates. These studies suggest that adolescent PTSD, while phenomenologically similar to adult PTSD, shows unique neurodevelopmental substrates that may impair recovery but could also be targeted in the context of adolescent neuroplasticity to improve outcomes. Both cross-sectional and longitudinal data suggest abnormal frontolimbic development compared with typically developing youths, a pattern that may differ from resilient youths. Whether current treatments such as trauma-focused psychotherapy engage these targets and restore healthy neurodevelopment remains an open question. We end our review by highlighting emerging areas and knowledge gaps that could be addressed to better characterize the biology underlying adolescent PTSD. Emerging studies in computational modeling of decision making, caregiver-related transmission of traumatic stress, and other areas may offer new targets that could harness adolescent neurobehavioral plasticity to improve resilience and recovery for some of our most vulnerable youths.

Effects of childhood trauma experience and COMT Val158Met polymorphism on brain connectivity in a multimodal MRI study

Childhood adversity may act as a stressor to produce a cascade of neurobiological effects that irreversibly alter neural development, setting the stage for developing psychopathology in adulthood. The catechol-O-methyltransferase (COMT) Val158Met polymorphism has received much attention as a candidate gene associated with environmental adversity, modifying risk for psychopathology. In this study, we aim to see how gene × brain × environment models give a more integrative understanding of brain modifications that contribute to predicting psychopathology related to childhood adversity. A large nonclinical sample of young adults completed Childhood Trauma Questionnaire (CTQ), behavioral scores, multimodal magnetic resonance imaging (MRI) scans, and genotyping. We utilized graph-based connectivity analysis in morphometric similarity mapping and resting-state functional MRI to investigate brain alterations. Relationships among COMT genotypes, CTQ score, imaging phenotypes, and behavioral scores were identified by multiple regression and mediation effect analysis. Significant main effect of CTQ score was found in anatomic connectivity of orbitofrontal cortex that was an outstanding mediator supporting the relationship between CTQ score and anxiety/harm-avoiding personality. We also noted the main effect of childhood trauma on reorganization of functional connectivity within the language network. Additionally, we found genotype × CTQ score interactions on functional connectivity of the right frontoparietal network as well as anatomic connectivity of motor and limbic regions. Our data demonstrate childhood adversity and COMT genotypes are associated with abnormal brain connectivity, structurally and functionally. Early identification of individuals at risk, assessment of brain abnormality, and cognitive interventions may help to prevent or limit negative outcomes.