The Bucharest Early Intervention Project: Adolescent mental health and adaptation following early deprivation

Faster pace of hippocampal growth mediates the association between perinatal adversity and childhood depression

Early life adversity has been posited to influence the pace of structural neurodevelopment. Most research, however, has relied on cross-sectional data, which do not reveal whether the pace of neurodevelopmental change is accelerated or slowed following early exposures. In a birth cohort study that included neuroimaging data obtained at 4.5, 6, and 7.5 years of age (N = 784), we examined associations among a cumulative measure of perinatal adversity relative to resources, nonlinear trajectories of hippocampal and amygdala volume, and children's subsequent depressive symptoms at 8.5 years of age. Greater adversity was associated with reduced bilateral hippocampal body volume in early childhood, but also to faster growth in the right hippocampal body across childhood. Further, the association between adversity and childhood depressive symptoms was mediated by faster hippocampal body growth. These findings suggest that perinatal adversity is biologically embedded in hippocampal structure development, including an accelerated pace of change in the right hippocampal body that is implicated in children's psychopathology risk. In addition, our findings suggest that reduced hippocampal volume is not inconsistent with accelerated hippocampal change; these aspects of structural development may typically co-occur, as smaller regional volumes in early childhood were associated with faster growth across childhood.

Early life adversity in primates: Behavioral, endocrine, and neural effects

BACKGROUND

Evidence suggests that early life adversity is associated with maladaptive behaviors and is commonly an antecedent of stress-related psychopathology. This is particularly relevant to rearing in primate species as infant primates depend on prolonged, nurturant rearing by caregivers for normal development. To further understand the consequences of early life rearing adversity, and the relation among alterations in behavior, physiology and brain function, we assessed young monkeys that had experienced maternal separation followed by peer rearing with behavioral, endocrine and multimodal neuroimaging measures.

METHODS

50 young rhesus monkeys were studied, half of which were rejected by their mothers and peer reared, and the other half were reared by their mothers. Assessments were performed at approximately 1.8 years of age and included: threat related behavioral and cortisol responses, cerebrospinal fluid (CSF) measurements of oxytocin and corticotropin releasing hormone (CRH), and multimodal neuroimaging measures (anatomical scans, resting functional connectivity, diffusion tensor imaging, and threat-related regional glucose metabolism).

RESULTS

The results demonstrated alterations across behavioral, endocrine, and neuroimaging measures in young monkeys that were reared without their mothers. At a behavioral level in response to a potential threat, peer reared animals engaged in significantly less freezing behavior (p = 0.022) along with increased self-directed behaviors (p < 0.012). Levels of oxytocin in the CSF, but not plasma, were significantly reduced in the peer reared animals (p = 0.019). No differences in plasma cortisol or CSF CRH were observed. Diffusion tensor imaging revealed significantly decreased white matter density across the brain. Exploratory correlational and permutation analyses suggest that the impact of peer rearing on behavior, endocrine and brain structural alterations are mediated by separate parallel mechanisms.

CONCLUSIONS

Taken together, these results demonstrate in NHPs the importance of maternal rearing on the development of brain, behavior and hormonal systems that are linked to social functioning and adaptive responses. The findings suggest that the effects of maternal deprivation are mediated via multiple independent pathways which may account for the heterogeneity in behavioral and biological alterations observed in individuals that have experienced this early life adversity.

Stress as a mediator of brain alterations in attention-deficit hyperactivity disorder: A systematic review

OBJECTIVE

Stress is a known risk factor for numerous psychopathologies, whereas evidence is lacking regarding the specific consequences of stress on the neural basis of attention-deficit hyperactivity disorder (ADHD). A systematic literature review was thus conducted to clarify the role of stress in the association between the resulting alterations of brain structure, connectivity, and function in ADHD.

METHODS

The study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and the protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO) under identifier CRD42023379809. A systematic search of the PubMed and CINAHL databases was conducted for articles published prior to December 22nd, 2022. Retrieved literature was screened in Rayyan and data extraction was performed with respect to neuroimaging, stress exposure, and ADHD outcomes. The Quality in Prognosis Studies (QUIPS) tool was adapted based on the Conducting Systematic Reviews and Meta-Analyses of Observational Studies of Etiology (COSMOS-E) guidance article to assess risk of bias and quality of studies. Strength of the evidence was assessed under the guidance of the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system.

RESULTS

Screening 25,026 non-duplicate articles yielded 20 eligible studies for inclusion. Exposure to early life trauma, institutionalization, prenatal smoking or alcohol consumption, air pollution, low socioeconomic status, or low birth weight were associated with alterations in brain structure, function, and connectivity in ADHD. However, most studies did not provide strong evidence due to small sample sizes and lack of statistical approaches to determine a direct mediation of the association between stress and ADHD by neural outcomes.

CONCLUSION

This systematic review was the first to summarize evidence of structural and functional stress-associated alterations in the brain, which were found to be directly and indirectly associated with ADHD outcomes. Overall, stress requires consideration as a significant determinant of neurodevelopmental outcomes in ADHD. However, extensive further research is warranted due to little available evidence and the difficulty of obtaining clear results. In light of such a complex research question, in order to confirm findings, provide further evidence, and establish causality systematic longitudinal studies would be required. Investigating the topic may provide invaluable information when it comes to tailoring prevention and treatment strategies in ADHD, and should be pursued in order to integrate the factor of stress into a more comprehensive understanding of ADHD.

Postnatal maternal care moderates the effects of prenatal bisphenol exposure on offspring neurodevelopmental, behavioral, and transcriptomic outcomes

Bisphenols (BPs), including BPA and "BPA-free" structural analogs, are commonly used plasticizers that are present in many plastics and are known endocrine disrupting chemicals. Prenatal exposure to BPA has been associated with negative neurodevelopmental and behavioral outcomes in children and rodent models. Prenatal BPA exposure has also been shown to impair postnatal maternal care provisioning, which can also affect offspring neurodevelopment and behavior. However, there is limited knowledge regarding the biological effects of prenatal exposure to bisphenols other than BPA and the interplay between prenatal BP exposure and postnatal maternal care on adult behavior. The purpose of the current study was to determine the interactive impact of prenatal BP exposure and postnatal maternal care on neurodevelopment and behavior. Our findings suggest that the effects of prenatal BP exposure on eye-opening, adult attentional set shifting and anxiety-like behavior in the open field are dependent on maternal care in the first five days of life. Interestingly, maternal care might also attenuate the effects of prenatal BP exposure on eye opening and adult attentional set shifting. Finally, transcriptomic profiles in male and female medial prefrontal cortex and amygdala suggest that the interactive effects of prenatal BP exposure and postnatal maternal care converge on estrogen receptor signaling and are involved in biological processes related to gene expression and protein translation and synthesis. Overall, these findings indicate that postnatal maternal care plays a critical role in the expression of the effects of prenatal BP exposure on neurodevelopment and adult behavior. Understanding the underlying biological mechanisms involved might allow us to identify potential avenues to mitigate the adverse effects of prenatal BP exposure and improve health and well-being in human populations.

Childhood Experiences of Alternative Care and Callousness/Unemotionality: A Conceptual Model, Scoping Review, and Research Agenda

Individuals with experiences of alternative care (AC; i.e., out-of-home care and institutional care) are at high risk for various mental health and relational problems stemming from exposure to serious attachment disruptions, loss, and complex trauma. Yet, despite the interpersonal context of their significant adversities, surprisingly there is scant research explicitly focusing on callousness/unemotionality (e.g., lack of guilt, callous disregard for others) in this population. This paper provides the first conceptual model for, and systematic scoping review of, callousness/unemotionality in children and young people with experiences of AC. In a comprehensive search of nine databases, 22 articles involving samples of participants in AC or with histories of AC, were identified for inclusion. The pattern of findings revealed that callous-unemotional and psychopathic traits are elevated in children and young people with AC experiences, and positively associated with AC. Moreover, results showed associations between these traits and various psychosocial correlates, most consistently with externalizing and internalizing problems and attachment-related problems. Only two intervention studies were located, one of which found benefits of training and supporting foster caregivers for reducing callous-unemotional traits. These findings are discussed with respect to gaps in the literature, future research directions, and trauma-informed practice to assess and treat callousness/unemotionality in children and young people with experiences of AC.

[Innovative Integrative Approach in the Trauma Treatment in the First Years of Life: Integrative Attachment-Based TraumaTherapy for Infants and Toddlers]

Untreated trauma in the first years of life has profound consequences for the further psychological, neurobiological and physical development of those affected.The earlier psychotherapeutic treatment takes place, the sooner the consequences can bemitigated or even prevented. Integrative Attachment-Based TraumaTherapy for Infants and Toddlers (I.B.T.®) describes an innovative approach that incorporates treatment aspects of proven trauma integrativemethods such as EMDR and trauma narrative, as well as elements of systemic, attachment-oriented and stressorbased psychotherapy. Treatment includes work with attachment figures, improving the quality of attachment between caregivers and child, as well as direct trauma integrative work on the infant and toddler themselves. Experience to date shows a rapid, complete remission of symptoms, as well as an improvement in the quality of attachment between caregivers and child.

Charting the social neuroscience of human attachment (SoNeAt)

This introduction aims to set out the potential as well as some of the pitfalls of the newly emerging area of the Social Neuroscience of Human Attachment (SoNeAt). To organize and interconnect the burgeoning empirical studies in this line of research, including those in this special issue, we outline a programmatic framework including an extension of our conceptual proposals NAMA and NAMDA to guide future research. We hope that this special issue will act as a stimulus for redoubling our efforts advancing the newly emerging SoNeAt area bridging attachment theory and social neuroscience.