Early maternal and paternal caregiving moderates the links between preschoolers' reactivity and regulation and maturation of the HPA-immune axis

Entry Into Boarding Preschool Is Associated With Increased Stress and School Refusal

In western China, many socioeconomically disadvantaged rural children remain at preschools for extremely long hours: they start to receive boarding services as young as 3 years old and remain at preschools for 4 to 5 consecutive days weekly. Although the quality of childcare is generally poor in these preschools, extremely long school hours and prolonged separation from primary caregivers may induce additional stress and lead to school maladjustment among boarding preschoolers. This study examines the impact of boarding experience on preschool beginners' social adjustment and stress responses, as indicated by their saliva alpha-amylase (sAA) and cortisol. A total of over 900 saliva samples of 31 boarding and 30 non-boarding preschoolers (mean age = 44.0 months, SD = 9.8 months) were collected over 12 weeks after they entered preschools. Primary caregivers reported children's behavioural problems and school refusal. Boarders experienced a larger mid-morning to mid-afternoon rise in cortisol than non-boarders on the second-to-last weekdays but not on the first weekdays. Non-boarders experienced an accelerated decrease in sAA during the 12 weeks, whereas boarders did not. Differences in cortisol and sAA patterns indicate potential increased stress for boarders, which might be associated with their more prevalent school-refusal behaviour than non-boarders. The findings underscore that entry into boarding preschool may cause stress and school refusal in rural Chinese children during their transition to preschool. Additional contacts with primary caregivers during this transition are needed to support boarders emotionally.

Systematic review: the impact of maternal pre-and postnatal cannabis use on the behavioral and emotional regulation in early childhood

Prenatal exposure to alcohol and tobacco has been associated with child regulatory abilities and problems, but less is known about the associations with cannabis exposure. This review seeks to address this gap primarily focusing on the effects of maternal cannabis use on the child. Thus, we investigate the association between pre- and postnatal cannabis exposure of the child and regulatory abilities and problems, as well as the underlying neurobiological mechanisms potentially mediating the associations. According to the PRISMA guidelines, a systematic literature review was performed based on a systematic literature search through Medline (PubMed), Web of Science and PsycInfo, including studies assessing children aged 0-6 years with cannabis exposure in the preconception, pre-or postnatal period (preconception, pre- and postnatal cannabis exposure [PCE]) and investigating child regulatory abilities, regulatory problems or neurobiological mechanisms. Of n = 1061 screened articles, n = 33 were finally included. Diminished regulatory abilities are more likely to be found in infants after PCE, while specific regulatory problems tend to be more frequently found after two years of age. Possible mechanisms are related to changes in methylation and expression of key genes involved in endocannabinoid, dopaminergic and opioid systems, increased cortisol reactivity and altered Secretory Immunoglobulin A levels. Furthermore, PCE has been associated with changes in brain structure and connectivity. Current findings indicate that PCE is associated with both age-dependent alterations in self-regulation and neurobiological changes in young children. However, evidence is limited due to the number of studies, small sample sizes and lack of control for maternal psychopathology. Longitudinal studies including psychometric data from mothers are needed in order to further understand the implications of PCE.Trial registration: The review is registered with PROSPERO (ID: CRD42023425115).

Breast milk oxytocin and s-IgA modulate infant biomarkers and social engagement; The role of maternal anxiety

Breastfeeding has long been known to improve infants' health and mental development and to enhance the mother-infant bond, but much less research focused on the biological composition of breast milk and its associations with the infant's biomarkers and social development. In this exploratory study, we measured oxytocin (OT) and secretory immunoglobulin-A (s-IgA), the most abundant antibody in breast milk, and evaluated their associations with the same biomarkers in infant saliva and, consequently, with infant social engagement behavior. Fifty-five mother-infant dyads were home-visit and OT and s-IgA were assessed from breast milk and from infant saliva before and after a free-play interaction. Infant social behavior was coded offline using the Coding Interactive Behavior (CIB) and maternal anxiety self-reported. A path model revealed that mother's breast milk s-IgA impacted child social engagement via its links with child OT. In parallel, maternal breast milk OT was linked with infant social behavior through its association with the infant's immunity. This path was moderated by maternal anxiety; only in cases of high anxiety breast milk OT was positively connected to infant s-IgA. Our study, the first to measure OT and s-IgA in both breast milk and infant saliva in relation to observed social behavior, underscores the need for much further research on the dynamic interplay between breast milk composition, infant biomarkers, maternal mental health, and infant social outcomes. Results may suggest that biological systems in breast milk integrate to prepare infants to function in their social ecology through bio-behavioral feedback loops that signal the degree of stress in the environment.

Impact of low-level prenatal alcohol exposure and maternal stress on autonomic regulation

BACKGROUND

Prenatal alcohol exposure (PAE) impacts the neurodevelopment of the fetus, including the infant's ability to self-regulate. Heart rate variability (HRV), that is, the beat-to-beat variability in heart rate, is a non-invasive measurement that can indicate autonomic nervous system (ANS) function/dysfunction.

METHODS

The study consisted of a subset of our ENRICH-2 cohort: 80 participants (32 PAE and 48 Controls) who had completed three visits during pregnancy. The participants completed a comprehensive assessment of PAE and other substances throughout pregnancy and assessments for stress, anxiety, and depression in the third trimester. At 24 h of age, infant HRV was assessed in the hospital during the clinically indicated heel lance; 3- to 5-min HRV epochs were obtained during baseline, heel lancing, and recovery episodes.

RESULTS

Parameters of HRV differed in infants with PAE compared to Controls during the recovery phase of the heel lance (respiratory sinus arrhythmia (RSA) and high-frequency (HF), p < 0.05). Increased maternal stress was also strongly associated with abnormalities in RSA, HF, and low-frequency / high-frequency (LF/HF, p's < 0.05).

CONCLUSIONS

Alterations in ANS regulation associated with PAE and maternal stress may reflect abnormal development of the hypothalamic-pituitary-adrenal axis and have long term implications for infant responsiveness and self-regulation.

IMPACT

Previous studies have focused on effects of moderate to heavy prenatal alcohol exposure (PAE) on autonomic dysregulation, but little is known about the effects of lower levels of PAE on infant self-regulation and heart rate variability (HRV). Prenatal stress is another risk factor for autonomic dysregulation. Mild PAE impacts infant self-regulation, which can be assessed using HRV. However, the effect of prenatal stress is stronger than that of mild PAE or other mental health variables on autonomic dysregulation.

Salivary secretory immunoglobulin A as a potential biomarker of psychosocial stress response during the first stages of life: A systematic review

Mucosal secretory immunoglobulin A (s-IgA) has been recognized as a key component of human first line defense against infection. However, its reactivity to psychosocial stressors is poorly understood. This systematic review aimed to explore whether s-IgA levels changed after psychosocial stress in subjects under the age of 18. Fifteen articles were included. s-IgA basal levels are increased in children older than 9 years old exposed to stress. Furthermore, s-IgA seems to follow a circadian rhythm, which is altered under stress conditions. Finally, the collective evidence suggests that salivary s-IgA rapidly increases under acute stress after puberty. Overall, our review indicates that s-IgA could be considered a potential psychosocial stress biomarker of interest for pediatric and child-juvenile psychiatric population. Further studies are needed to validate the role of s-IgA circadian rhythm and basal levels as psychosocial stress biomarkers and disentangle the role of age and type of stressor.

Developmental Cascades Link Maternal-Newborn Skin-to-Skin Contact with Young Adults' Psychological Symptoms, Oxytocin, and Immunity; Charting Mechanisms of Developmental Continuity from Birth to Adulthood

Premature birth disrupts the continuity of maternal-newborn bodily contact, which underpins the development of physiological and behavioral support systems. Utilizing a unique cohort of mother-preterm dyads who received skin-to-skin contact (Kangaroo Care, KC) versus controls, and following them to adulthood, we examined how a touch-based neonatal intervention impacts three adult outcomes; anxiety/depressive symptoms, oxytocin, and secretory immunoglobulin A (s-IgA), a biomarker of the immune system. Consistent with dynamic systems' theory, we found that links from KC to adult outcomes were indirect, mediated by its effects on maternal mood, child attention and executive functions, and mother-child synchrony across development. These improvements shaped adult outcomes via three mechanisms; (a) "sensitive periods", where the infancy improvement directly links with an outcome, for instance, infant attention linked with higher oxytocin and lower s-IgA; (b) "step-by-step continuity", where the infancy improvement triggers iterative changes across development, gradually shaping an outcome; for instance, mother-infant synchrony was stable across development and predicted lower anxiety/depressive symptoms; and (c) "inclusive mutual-influences", describing cross-time associations between maternal, child, and dyadic factors; for instance, from maternal mood to child executive functions and back. Findings highlight the long-term impact of a birth intervention across development and provide valuable insights on the mechanisms of "developmental continuity", among the key topics in developmental research.

Like Parent, like Child: General and Specific Associations Between Parents’ and Children’s Binary Gender Identity in a Gender Egalitarian Context

There is ample scientific evidence for the importance of parental gender socialization in children’s binary gender development. Surprisingly, little is known about the role of parents’ own gender identity in the binary gender identity development of their children. Therefore, the present study investigated the association between parents’ and children’s binary gender identity (i.e., similarity to same- and other-gender individuals) in a sample of 142 Dutch families with a child between the ages of 6 and 12 years old. The Dutch context is characterized by relatively high gender equality. Both parents and their children answered questions about their similarity to same-gender and other-gender individuals. Generalized estimating equations revealed that parents’ same-gender similarity and parents’ other-gender similarity were positively associated with their children’s same- and other-gender-similarity, respectively. In addition, more other-gender similarity in parents was associated with less same-gender similarity in girls, but more same-gender similarity in boys. Parents who reported high similarity with both genders were more likely to have children who also reported higher similarity with both genders. These findings indicate that parents’ own binary gender identity is related in general and specific ways to their children’s binary gender identity development. Parents should be made aware of their role in children’s binary gender identity development. Yet, more research on different types of gender identity in parents and their children is necessary.

Associations between the human immune system and gut microbiome with neurodevelopment in the first 5 years of life: A systematic scoping review

The aim of this review was to map the literature assessing associations between maternal or infant immune or gut microbiome biomarkers and child neurodevelopmental outcomes within the first 5 years of life. We conducted a PRISMA-ScR compliant review of peer-reviewed, English-language journal articles. Studies reporting gut microbiome or immune system biomarkers and child neurodevelopmental outcomes prior to 5 years were eligible. Sixty-nine of 23,495 retrieved studies were included. Of these, 18 reported on the maternal immune system, 40 on the infant immune system, and 13 on the infant gut microbiome. No studies examined the maternal microbiome, and only one study examined biomarkers from both the immune system and the gut microbiome. Additionally, only one study included both maternal and infant biomarkers. Neurodevelopmental outcomes were assessed from 6 days to 5 years. Associations between biomarkers and neurodevelopmental outcomes were largely nonsignificant and small in effect size. While the immune system and gut microbiome are thought to have interactive impacts on the developing brain, there remains a paucity of published studies that report biomarkers from both systems and associations with child development outcomes. Heterogeneity of research designs and methodologies may also contribute to inconsistent findings. Future studies should integrate data across biological systems to generate novel insights into the biological underpinnings of early development.

Major depression, temperament, and social support as psychosocial mechanisms of the intergenerational transmission of parenting styles

In this three-generation longitudinal study of familial depression, we investigated the continuity of parenting styles, and major depressive disorder (MDD), temperament, and social support during childrearing as potential mechanisms. Each generation independently completed the Parental Bonding Instrument (PBI), measuring individuals' experiences of care and overprotection received from parents during childhood. MDD was assessed prospectively, up to 38 years, using the semi-structured Schedule for Affective Disorders and Schizophrenia (SADS). Social support and temperament were assessed using the Social Adjustment Scale - Self-Report (SAS-SR) and Dimensions of Temperament Scales - Revised, respectively. We first assessed transmission of parenting styles in the generation 1 to generation 2 cycle (G1→G2), including 133 G1 and their 229 G2 children (367 pairs), and found continuity of both care and overprotection. G1 MDD accounted for the association between G1→G2 experiences of care, and G1 social support and temperament moderated the transmission of overprotection. The findings were largely similar when examining these psychosocial mechanisms in 111 G2 and their spouses (G2+S) and their 136 children (G3) (a total of 223 pairs). Finally, in a subsample of families with three successive generations (G1→G2→G3), G2 experiences of overprotection accounted for the association between G1→G3 experiences of overprotection. The results of this study highlight the roles of MDD, temperament, and social support in the intergenerational continuity of parenting, which should be considered in interventions to "break the cycle" of poor parenting practices across generations.

Parenting Styles, Mental Health, and Catastrophizing in Women with Chronic Pelvic Pain: A Case-Control Study

Chronic pelvic pain (CPP) in women is a highly prevalent condition worldwide and requires multimodal treatment. Adverse childhood experiences have been associated with CPP in women, while allodynia and poor outcomes have been linked to pain catastrophizing in these patients. Pain perception has been associated with parenting style during childhood. The objective of this study was to investigate the association between parenting style, pain catastrophizing, anxiety, depression and CPP in women. A case-control study was conducted between May 2018 and August 2021 with 123 women with CPP and 123 pain-free controls. Questionnaires were used to collect participants' data. The association between parenting style and CPP was assessed using multiple logistic regression, with odds ratios (OR) and 95% confidence intervals (CI) being calculated. The correlation between catastrophizing, pain intensity, pain duration, anxiety, depression, and parenting style in women with CPP was assessed using Spearman's rank correlation coefficient (r). A higher frequency of low maternal care (60.7% versus 45.2%; p = 0.026), anxiety (79.7% versus 56.9%; p < 0.001), depression (73.2% versus 56.1%; p = 0.008) and physical violence (31.7% versus 14.6%; p = 0.003) was found in the CPP group compared to the controls. There was no association between parenting style and CPP in the adjusted analysis. A positive correlation was found between catastrophizing and pain intensity (r = 0.342; p < 0.001), anxiety (r = 0.271; p = 0.002), depression (r = 0.272; p = 0.002), and maternal overprotection (r = 0.185; p = 0.046). A negative correlation was found between anxiety and maternal (r = -0.184; p = 0.047) and paternal (r = -0.286; p = 0.006) care and between depression and maternal (r = -0.219; p = 0.018) and paternal (r = -0.234; p = 0.026) care. The present results suggest a significant but weak association of parenting style with pain catastrophizing, the mental health of women with CPP, and the way in which they experience pain.

Peripartum effects of synthetic oxytocin: The good, the bad, and the unknown

The first clinical applications of oxytocin (OT) were in obstetrics as a hormone to start and speed up labor and to control postpartum hemorrhage. Discoveries in the 1960s and 1970s revealed that the effects of OT are not limited to its peripheral actions around birth and milk ejection. Indeed, OT also acts as a neuromodulator in the brain affecting fear memory, social attachment, and other forms of social behaviors. The peripheral and central effects of OT have been separately subject to extensive scrutiny. However, the effects of peripheral OT-particularly in the form of administration of synthetic OT (synOT) around birth-on the central nervous system are surprisingly understudied. Here, we provide a narrative review of the current evidence, suggest putative mechanisms of synOT action, and provide new directions and hypotheses for future studies to bridge the gaps between neuroscience, obstetrics, and psychiatry.

Integrative Model of Human-Animal Interactions: A One Health-One Welfare Systemic Approach to Studying HAI

The Integrative Model of Human-Animal Interactions (IMHAI) described herewith provides a conceptual framework for the study of interspecies interactions and aims to model the primary emotional processes involved in human-animal interactions. This model was developed from theoretical inputs from three fundamental disciplines for understanding interspecies interactions: neuroscience, psychology and ethology, with the objective of providing a transdisciplinary approach on which field professionals and researchers can build and collaborate. Seminal works in affective neuroscience offer a common basis between humans and animals and, as such, can be applied to the study of interspecies interactions from a One Health-One Welfare perspective. On the one hand, Jaak Panksepp's research revealed that primary/basic emotions originate in the deep subcortical regions of the brain and are shared by all mammals, including humans. On the other hand, several works in the field of neuroscience show that the basic physiological state is largely determined by the perception of safety. Thus, emotional expression reflects the state of an individual's permanent adaptation to ever-changing environmental demands. Based on this evidence and over 5 years of action research using grounded theory, alternating between research and practice, the IMHAI proposes a systemic approach to the study of primary-process emotional affects during interspecies social interactions, through the processes of emotional transfer, embodied communication and interactive emotional regulation. IMHAI aims to generate new hypotheses and predictions on affective behavior and interspecies communication. Application of such a model should promote risk prevention and the establishment of positive links between humans and animals thereby contributing to their respective wellbeing.

The Neural Basis of Human Fatherhood: A Unique Biocultural Perspective on Plasticity of Brain and Behavior

With the growing involvement of fathers in childrearing and the application of neuroscientific tools to research on parenting, there is a need to understand how a father's brain and neurohormonal systems accommodate the transition to parenthood and how such neurobiological changes impact children's mental health, sociality, and family functioning. In this paper, we present a theoretical model on the human father's brain and the neural adaptations that take place when fathers assume an involved role. The neurobiology of fatherhood shows great variability across individuals, societies, and cultures and is shaped to a great extent by bottom-up caregiving experiences and the amount of childrearing responsibilities. Mechanisms of mother-father coparental brain coordination and hormonal correlates of paternal behavior are detailed. Adaptations in the father's brain during pregnancy and across the postpartum year carry long-term implications for children's emotion regulation, stress management, and symptom formation. We propose a new conceptual model of HEALthy Father Brain that describes how a father's brain serves as a source of resilience in the context of family adversity and its capacity to "heal", protect, and foster social brain maturation and functionality in family members via paternal sensitivity, attunement, and support, which, in turn, promote child development and healthy family functioning. Father's brain provides a unique model on neural plasticity as sustained by committed acts of caregiving, thereby affording a novel perspective on the brain basis of human affiliation.

Children’s Views About Their Future Career and Family Involvement: Associations With Children’s Gender Schemas and Parents’ Involvement in Work and Family Roles

Substantial gender disparities in career advancement are still apparent, for instance in the gender pay gap, the overrepresentation of women in parttime work, and the underrepresentation of women in managerial positions. Regarding the developmental origins of these gender disparities, the current study examined whether children’s views about future career and family involvement were associated with children’s own gender schemas (gender stereotypes, gender identity) and parents’ career- and family-related gender roles. Participants were 142 Dutch families with a child between the ages of 6 and 12 years old (M = 9.80, SD = 1.48, 60% girls). The families had different compositions (1 parent, 2 parents, 1 to 3 children). Children completed a computer task assessing gender stereotypes about toys and questionnaires on gender identity (i.e., felt similarity to same- and other-gender children) and their views about future career and family involvement. Parents reported their occupation, work hours, and task division in the home, which were combined in a composite variable reflecting gender-typicality of career and family involvement. Generalized estimation equations were used to take into account dependency between family members. Results revealed that parents’, and especially mothers’, gender-typical career and family involvement was associated with children’s gender-typical views about future career and family involvement. In addition, children’s felt similarity to the same gender was associated with children’s gender-typical expectations about career and family involvement. These findings suggest that parents’ career, work hours, and task division in the home, together play an important role in how their children envision their future work and family roles. Children themselves also play an active role in developing this vision for the future by their own gender identity, specifically by how similar they feel to individuals of the same gender. To reduce gender disparities in the occupational and domestic domain, programs need to be designed that focus on parental role modeling in the family as well as children’s gender identity development.