Multigenerational adversity impacts on human gut microbiome composition and socioemotional functioning in early childhood.

Adversity exposures in the prenatal and postnatal period are associated with an increased risk for psychopathology, which can be perpetuated across generations. Nonhuman animal research highlights the gut microbiome as a putative biological mechanism underlying such generational risks. In a sample of 450 mother-child dyads living in Singapore, we examined associations between three distinct adversity exposures experienced across two generations-maternal childhood maltreatment, maternal prenatal anxiety, and second-generation children's exposure to stressful life events-and the gut microbiome composition of second-generation children at 2 y of age. We found distinct differences in gut microbiome profiles linked to each adversity exposure, as well as some nonaffected microbiome features (e.g., beta diversity). Remarkably, some of the microbial taxa associated with concurrent and prospective child socioemotional functioning shared overlapping putative functions with those affected by adversity, suggesting that the intergenerational transmission of adversity may have a lasting impact on children's mental health via alterations to gut microbiome functions. Our findings open up a new avenue of research into the underlying mechanisms of intergenerational transmission of mental health risks and the potential of the gut microbiome as a target for intervention.

Dimensions of the language environment in infancy and symptoms of psychopathology in toddlerhood.

The quality of the early environment influences the development of psychopathology. Children who are deprived of sufficient environmental enrichment in infancy may be at higher risk for developing symptoms of psychopathology in toddlerhood. In this study, we investigated the prospective association between naturalistic measures of adult language input obtained through passive monitoring of infants' daily environments and emerging psychopathology in toddlerhood. In a sample of 100 mothers and their infants recruited from the community (mean age [range] = 6.73 [5-9] months), we used the Language ENvironment Analysis (LENA) system to measure multiple dimensions of infants' language environments, including both the quantity and consistency of adult speech and conversational turns in infants' daily lives as well as the quantity of infant vocalizations. Subsequently, during toddlerhood (mean age [range] = 18.29 [17-21] months), mothers reported on their children's symptoms of psychopathology. Infants who experienced more consistent adult speech and conversational turns had lower symptoms of psychopathology in toddlerhood, independent of negative emotionality in infancy, maternal depressive symptoms, and laboratory-based measures of maternal sensitivity. These findings have implications for the measurement of environmental factors that may confer risk and resilience to emerging psychopathology.

Suicidal behaviors among Latina adolescents: An ecodevelopmental approach and narrative review.

INTRODUCTION: For the past several decades, Latina adolescents have consistently shown high rates of suicidal behaviors (i.e., suicidal ideation, planning, and attempts), higher than Latino adolescents and adolescents of most other ethnic groups. Yet, progress toward establishing evidence-based intervention efforts to address this urgent public health issue has been slow. The purpose of this narrative review is to summarize empirical findings on etiological factors associated with Latina adolescent suicidal behaviors using an ecodevelopmental, gender-specific framework that contextualizes Latina adolescent development. METHODS: To be included, peer reviewed empirical manuscripts had to focus on suicidal behaviors (i.e., suicide attempts, suicide plan, and/or suicidal ideation) of adolescents (ages 11-19 or in grades 7-12) who self-identified as either Latina or Hispanic and a girl in the United States. RESULTS: A total of 19 studies met review criteria and focused on microsystemic and intrapersonal predictors. Microsystemic predictors included family (i.e., family-adolescent discrepancies in acculturation, family functioning, family-daughter interactions), peer (i.e., victimization, friendships), and school (i.e., functioning, achievement) factors, while intrapersonal predictors were emotional vulnerability, psychosocial functioning, and substance use. CONCLUSIONS: Family-related phenomena were the most widely studied. Research on school and peer microsystems was comparatively sparse, and several promising intrapersonal development factors have been underexplored. A notable limitation of existing studies is that samples consisted primarily of U.S.-born adolescents living in urban areas. Additional research is needed to characterize factors on other ecodevelopmental levels, identify resilience processes, and examine within-group diversity among Latina adolescents. Implications for intervention and future directions are discussed.

In a father's mind: paternal reflective functioning, sensitive parenting, and protection against socioeconomic risk.

This study utilized attachment theory as a framework for understanding how fathers' reflective functioning (RF) and social emotional (SE) and autonomy (AU) supportive behaviors relate to children's emotion regulation (ER) beyond effects of mothers' RF. Moreover, the study explored how fathers' RF may be a protective factor against risks associated with low income. Fathers (n = 77) and their toddlers participated. Fathers' RF was coded from narrative accounts of parenting and mothers' RF was assessed by questionnaire. Fathers' SE and AU supportive behaviors were coded from observations of father-child interactions; toddlers' ER was assessed as distress on a challenging task. Results show that, after accounting for mothers' RF, fathers' RF was directly associated with SE supportive behaviors; RF moderated the association between income and AU supportive behaviors. Fathers' SE and AU supportive behaviors were associated with children's distress. Fathers' RF plays a central role in parenting and in children's ER.

A comparison of the infant gut microbiome before versus after the start of the covid-19 pandemic.

The COVID-19 pandemic and resulting public health directives led to many changes in families' social and material environments. Prior research suggests that these changes are likely to impact composition of the gut microbiome, particularly during early childhood when the gut microbiome is developing most rapidly. Importantly, disruption to the gut microbiome during this sensitive period can have potentially long-lasting impacts on health and development. In the current study, we compare gut microbiome composition among a socioeconomically and racially diverse group of 12-month old infants living in New York City who provided stool samples before the pandemic (N = 34) to a group who provided samples during the first 9-months of the pandemic (March-December 2020; N = 20). We found that infants sampled during the pandemic had lower alpha diversity of the microbiome, lower abundance of Pasteurellaceae and Haemophilus, and significantly different beta diversity based on unweighted Unifrac distance than infants sampled before the pandemic. Exploratory analyses suggest that gut microbiome changes due to the pandemic occurred relatively quickly after the start of the pandemic and were sustained. Our results provide evidence that pandemic-related environmental disruptions had an impact on community-level taxonomic diversity of the developing gut microbiome, as well as abundance of specific members of the gut bacterial community.

White matter myelination during early infancy is linked to spatial gradients and myelin content at birth.

Development of myelin, a fatty sheath that insulates nerve fibers, is critical for brain function. Myelination during infancy has been studied with histology, but postmortem data cannot evaluate the longitudinal trajectory of white matter development. Here, we obtained longitudinal diffusion MRI and quantitative MRI measures of longitudinal relaxation rate (R1) of white matter in 0, 3 and 6 months-old human infants, and developed an automated method to identify white matter bundles and quantify their properties in each infant's brain. We find that R1 increases from newborns to 6-months-olds in all bundles. R1 development is nonuniform: there is faster development in white matter that is less mature in newborns, and development rate increases along inferior-to-superior as well as anterior-to-posterior spatial gradients. As R1 is linearly related to myelin fraction in white matter bundles, these findings open new avenues to elucidate typical and atypical white matter myelination in early infancy.

Infants' cortex undergoes microstructural growth coupled with myelination during development.

Development of cortical tissue during infancy is critical for the emergence of typical brain functions in cortex. However, how cortical microstructure develops during infancy remains unknown. We measured the longitudinal development of cortex from birth  to six months of age  using multimodal quantitative imaging of cortical microstructure. Here we show that infants' cortex undergoes profound microstructural tissue growth during the first six months of human life. Comparison of postnatal to prenatal transcriptomic gene expression data demonstrates that myelination and synaptic processes are dominant contributors to this postnatal microstructural tissue growth. Using visual cortex as a model system, we find hierarchical microstructural growth: higher-level visual areas have less mature tissue at birth than earlier visual areas but grow at faster rates. This overturns the prominent view that visual areas that are most mature at birth develop fastest. Together, in vivo, longitudinal, and quantitative measurements, which we validated with ex vivo transcriptomic data, shed light on the rate, sequence, and biological mechanisms of developing cortical systems during early infancy. Importantly, our findings propose a hypothesis that cortical myelination is a key factor in cortical development during early infancy, which has important implications for diagnosis of neurodevelopmental disorders and delays in infants.