Love on the developing brain: Maternal sensitivity and infants' neural responses to emotion in the dorsolateral prefrontal cortex.

Infancy is a sensitive period of development, during which experiences of parental care are particularly important for shaping the developing brain. In a longitudinal study of N = 95 mothers and infants, we examined links between caregiving behavior (maternal sensitivity observed during a mother-infant free-play) and infants' neural response to emotion (happy, angry, and fearful faces) at 5 and 7 months of age. Neural activity was assessed using functional Near-Infrared Spectroscopy (fNIRS) in the dorsolateral prefrontal cortex (dlPFC), a region involved in cognitive control and emotion regulation. Maternal sensitivity was positively correlated with infants' neural responses to happy faces in the bilateral dlPFC and was associated with relative increases in such responses from 5 to 7 months. Multilevel analyses revealed caregiving-related individual differences in infants' neural responses to happy compared to fearful faces in the bilateral dlPFC, as well as other brain regions. We suggest that variability in dlPFC responses to emotion in the developing brain may be one correlate of early experiences of caregiving, with implications for social-emotional functioning and self-regulation.

Context-dependent approach and avoidance behavioral profiles as predictors of psychopathology.

Inhibition (a temperamental profile characterized by elevated levels of avoidance behaviors) is associated with increased likelihood for developing anxiety and depression, whereas exuberance (a temperamental profile characterized by elevated levels of approach behaviors) is associated with increased likelihood for developing externalizing conditions (e.g., attention deficit/hyperactivity disorder and conduct disorder). However, not all children who exhibit high levels of approach or avoidance behaviors develop emotional or behavioral problems. In this preregistered study, we assessed context-dependent profiles of approach and avoidance behaviors in 3-year-old children (N = 366). Using latent profile analysis, four groups were identified: nonsocial approachers, social approachers, social avoiders, and nonsocial avoiders. Analyses revealed that there were minimal differences in internalizing and externalizing symptoms across the four context-dependent groups. However, exploratory analyses assessed whether high levels of approach or avoidance combined across contexts, similar to findings reported in prior work, were related to psychopathology. Children identified as high in avoidance behavior at 3 years of age were more likely to show internalizing symptoms at 3 years of age but not at 5 years of age. Children high in approach were more likely to meet criteria for anxiety and externalizing disorders by age 5 years. These findings further our understanding of individual differences in how young children adjust their behavior based on contextual cues and may inform methods for identifying children at increased likelihood for the development of emotional and behavioral problems. RESEARCH HIGHLIGHTS: Context-dependent approach and avoidance profiles were identified in 3-year-old children using a person-centered approach. Children who were high in approach behavior, regardless of context, at age three had a higher likelihood for developing an anxiety or externalizing disorder by age five. These findings may help identify children at increased risk of developing emotional and behavioral problems.

Taking a lifespan approach to polygenic scores.

This commentary is a call to action for researchers to create and use genome-wide association studies (GWASs) with previously missed age groups (e.g., infancy, elderly), which will improve our ability to ask important developmental questions using genetic data to trace pathways across the lifespan.

A novel(ty) perspective of fear bias.

Grossmann presents an exciting and interesting theory on the function of fearfulness. In this commentary it is argued that fearfulness may be a byproduct of a larger executive functioning network and these early regulatory skills considered more broadly may be key building blocks for later cooperative behaviors.

Composition of the maternal gastrointestinal microbiome as a predictor of neonatal birth weight.

BACKGROUND: The biological mechanism by which the maternal gastrointestinal microbiota contributes to fetal growth and neonatal birth weight is currently unknown. The purpose of this study was to explore how the composition of the maternal microbiome in varying pre-gravid body mass index (BMI) groups are associated with neonatal birth weight adjusted for gestational age. METHODS: Retrospective, cross-sectional metagenomic analysis of bio-banked fecal swab biospecimens (n = 102) self-collected by participants in the late second trimester of pregnancy. RESULTS: Through high-dimensional regression analysis using principal components (PC) of the microbiome, we found that the best performing multivariate model explained 22.9% of the variation in neonatal weight adjusted for gestational age. Pre-gravid BMI (p = 0.05), PC3 (p = 0.03), and the interaction of the maternal microbiome with maternal blood glucose on the glucose challenge test (p = 0.01) were significant predictors of neonatal birth weight after adjusting for potential confounders including maternal antibiotic use during gestation and total gestational weight gain. CONCLUSIONS: Our results indicate a significant association between the maternal gastrointestinal microbiome in the late second trimester and neonatal birth weight adjusted for gestational age. Moderated by blood glucose at the time of the universal glucose screening, the gastrointestinal microbiome may have a role in the regulation of fetal growth. IMPACT: Maternal blood glucose in the late second trimester significantly moderates the relationship between the maternal gastrointestinal microbiome and neonatal size adjusted for gestational age. Our findings provide preliminary evidence for fetal programming of neonatal birth weight through the maternal gastrointestinal microbiome during pregnancy.

Shedding light on functional near-infrared spectroscopy and open science practices.

Open science practices work to increase methodological rigor, transparency, and replicability of published findings. We aim to reflect on what the functional near-infrared spectroscopy (fNIRS) community has done to promote open science practices in fNIRS research and set goals to accomplish over the next 10 years.

Infant and maternal responses to emotional facial expressions: A longitudinal study.

The current longitudinal study (N = 107) examined mothers' facial emotion recognition using reaction time and their infants' affect-based attention at 5, 7, and 14 months of age using eyetracking. Our results, examining maternal and infant responses to angry, fearful and happy facial expressions, show that only maternal responses to angry facial expressions were robustly and positively linked across time points, indexing a consistent trait-like response to social threat among mothers. However, neither maternal responses to happy or fearful facial expressions nor infant responses to all three facial emotions show such consistency, pointing to the changeable nature of facial emotion processing, especially among infants. In general, infants' attention toward negative emotions (i.e., angry and fear) at earlier timepoints was linked to their affect-biased attention for these emotions at 14 months but showed greater dynamic change across time. Moreover, our results provide limited evidence for developmental continuity in processing negative emotions and for the bidirectional interplay of infant affect-biased attention and maternal facial emotion recognition. This pattern of findings suggests that infants' affect-biased attention to facial expressions of emotion are characterized by dynamic changes.

Frontal asymmetry assessed in infancy using functional near-infrared spectroscopy is associated with emotional and behavioral problems in early childhood.

Frontal asymmetry (FA), the difference in brain activity between the left versus right frontal areas, is thought to reflect approach versus avoidance motivation. This study (2012-2021) used functional near-infrared spectroscopy to investigate if infant (Mage  = 7.63 months; N = 90; n = 48 male; n = 75 White) FA in the dorsolateral prefrontal cortex relates to psychopathology in later childhood (Mage  = 62.05 months). Greater right FA to happy faces was associated with increased internalizing (η2  = .09) and externalizing (η2  = .06) problems at age 5 years. Greater right FA to both happy and fearful faces was associated with an increased likelihood of a lifetime anxiety diagnosis (R2 > .13). FA may be an informative and early-emerging marker for psychopathology.

Beyond accidents: Young children's forgiveness of third-party intentional transgressors.

To maintain our cooperative relationships, it is critical that we repair these relationships when they are damaged by transgressions. Key to this repair is forgiveness. Previous research suggests that adults and children are more forgiving of remorseful transgressors than of unremorseful ones after accidental transgressions. However, little is known about whether children's forgiveness also takes the transgressors' intentions into account. Using a third-person video paradigm with children in the United States, Study 1 found that 6-year-olds (n = 20; 10 girls; 60% White) were more likely to negatively evaluate an intentional transgressor and give more resources to an accidental transgressor when both transgressors showed remorse, whereas 5-year-olds (n = 20; 10 girls; 80% White) showed this effect only in their resource distribution. Study 2 found that 6-year-olds (n = 18; 7 girls; 83% White) were more likely to positively evaluate and share more resources with a remorseful intentional transgressor than with an unremorseful intentional one. Thus, by school age in the United States, children's forgiveness, at least as bystanders, begins to take into account both the transgressor's intentions and the display of remorse.

Maternal recognition of positive emotion predicts sensitive parenting in infancy.

Research on parent-child relationships demonstrates the importance of maternal sensitivity for the development of children's emotion regulation, social competence, and health; thus, it is important to understand the emotional-cognitive capacities underlying maternal sensitivity. We followed 120 mothers and their full-term infants from the newborn period to 5 months postpartum. Mothers' emotion recognition during the newborn period was measured using a validated facial emotion recognition task assessing discrimination (d') of six facial expressions of emotion: happiness, fear, anger, sadness, disgust, and neutrality. Maternal behavior at 5 months postpartum was coded from a mother-infant free-play session using Ainsworth's Sensitivity Scales. Preregistered analyses revealed that mothers' ability to detect happiness specifically (but not other emotions such as fear or sadness) in the neonatal period predicted greater observed sensitivity 4 months later, ß = .30, p = .002, ΔR² = .08. Results suggest that maternal recognition of positive emotion may be uniquely predictive of sensitive behavior in low-stress parent-infant interaction contexts. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Examining the Role of Socioeconomic Status and Maternal Sensitivity in Predicting Functional Brain Network Connectivity in 5-Month-Old Infants.

Infancy is a sensitive period of human brain development that is plastically shaped by environmental factors. Both proximal factors, such as sensitive parenting, and distal factors, such as socioeconomic status (SES), are known predictors of individual differences in structural and functional brain systems across the lifespan, yet it is unclear how these familial and contextual factors work together to shape functional brain development during infancy, particularly during the first months of life. In the current study, we examined pre-registered hypotheses regarding the interplay between these factors to assess how maternal sensitivity, within the broader context of socioeconomic variation, relates to the development of functional connectivity in long-range cortical brain networks. Specifically, we measured resting-state functional connectivity in three cortical brain networks (fronto-parietal network, default mode network, homologous-interhemispheric connectivity) using functional near-infrared spectroscopy (fNIRS), and examined the associations between maternal sensitivity, SES, and functional connectivity in a sample of 5-month-old infants and their mothers (N = 50 dyads). Results showed that all three networks were detectable during a passive viewing task, and that maternal sensitivity was positively associated with functional connectivity in the default mode network, such that infants with more sensitive mothers exhibited enhanced functional connectivity in this network. Contrary to hypotheses, we did not observe any associations of SES with functional connectivity in the brain networks assessed in this study. This suggests that at 5 months of age, maternal sensitivity is an important proximal environmental factor associated with individual differences in functional connectivity in a long-range cortical brain network implicated in a host of emotional and social-cognitive brain processes.

Processing third-party social interactions in the human infant brain.

The understanding of developing social brain functions during infancy relies on research that has focused on studying how infants engage in first-person social interactions or view individual agents and their actions. Behavioral research suggests that observing and learning from third-party social interactions plays a foundational role in early social and moral development. However, the brain systems involved in observing third-party social interactions during infancy are unknown. The current study tested the hypothesis that brain systems in prefrontal and temporal cortex, previously identified in adults and children, begin to specialize in third-party social interaction processing during infancy. Infants (N = 62), ranging from 6 to 13 months in age, had their brain responses measured using functional near-infrared spectroscopy (fNIRS) while viewing third-party social interactions and two control conditions, infants viewing two individual actions and infants viewing inverted social interactions. The results show that infants preferentially engage brain regions localized within the dorsomedial prefrontal cortex when viewing third-party social interactions. These findings suggest that brain systems processing third-party social interaction begin to develop early in human ontogeny and may thus play a foundational role in supporting the interpretation of and learning from social interactions.

Variability in Infants' Functional Brain Network Connectivity Is Associated With Differences in Affect and Behavior.

Variability in functional brain network connectivity has been linked to individual differences in cognitive, affective, and behavioral traits in adults. However, little is known about the developmental origins of such brain-behavior correlations. The current study examined functional brain network connectivity and its link to behavioral temperament in typically developing newborn and 1-month-old infants (M [age] = 25 days; N = 75) using functional near-infrared spectroscopy (fNIRS). Specifically, we measured long-range connectivity between cortical regions approximating fronto-parietal, default mode, and homologous-interhemispheric networks. Our results show that connectivity in these functional brain networks varies across infants and maps onto individual differences in behavioral temperament. Specifically, connectivity in the fronto-parietal network was positively associated with regulation and orienting behaviors, whereas connectivity in the default mode network showed the opposite effect on these behaviors. Our analysis also revealed a significant positive association between the homologous-interhemispheric network and infants' negative affect. The current results suggest that variability in long-range intra-hemispheric and cross-hemispheric functional connectivity between frontal, parietal, and temporal cortex is associated with individual differences in affect and behavior. These findings shed new light on the brain origins of individual differences in early-emerging behavioral traits and thus represent a viable novel approach for investigating developmental trajectories in typical and atypical neurodevelopment.

Probing infants' sensitivity to pupil size when viewing eyes.

Sensitive responding to eye cues plays a key role in human social interactions. Pupil size provides subtle cues regarding a social interaction partner's arousal states. The current study assessed infants' sensitivity to and preference for differences in pupil size. Specifically, we examined White 14-month-old infants' pupillary responses when viewing own-race and other-race (Asian) eyes with dilating, constricting, and static medium-sized pupils. Our results show that, independent of race, infants' pupils dilated more when viewing eyes with dynamically changing (dilating and constricting) pupils than when viewing eyes with non-changing, static, and medium-sized pupils. We also measured infants' looking preferences, showing that, independent of race, infants preferentially attended to eyes with dilated pupils. Moreover, our results show that infants orient more quickly to pupillary changes in own-race eyes than in other-race eyes. These findings demonstrate that infants detect, but do not mimic, changes in pupil size in others and show a preference for eyes with dilated pupils.

Gut microbiota composition is associated with newborn functional brain connectivity and behavioral temperament.

The gut microbiome appears to play an important role in human health and disease. However, only little is known about how variability in the gut microbiome contributes to individual differences during early and sensitive stages of brain and behavioral development. The current study examined the link between gut microbiome, brain, and behavior in newborn infants (N = 63; M [age] = 25 days). Infant gut microbiome diversity was measured from stool samples using metagenomic sequencing, infant functional brain network connectivity was assessed using a resting state functional near infrared spectroscopy (rs-fNIRS) procedure, and infant behavioral temperament was assessed using parental report. Our results show that gut microbiota composition is linked to individual variability in brain network connectivity, which in turn mediated individual differences in behavioral temperament, specifically negative emotionality, among infants. Furthermore, virulence factors, possibly indexing pathogenic activity, were associated with differences in brain network connectivity linked to negative emotionality. These findings provide novel insights into the early developmental origins of the gut microbiome-brain axis and its association with variability in important behavioral traits. This suggests that the gut microbiome is an important biological factor to consider when studying human development and health.

Substance Use Disorders and COVID-19: Multi-Faceted Problems Which Require Multi-Pronged Solutions.

COVID-19 shocked health and economic systems leaving millions of people without employment and safety nets. The pandemic disproportionately affects people with substance use disorders (SUDs) due to the collision between SUDs and COVID-19. Comorbidities and risk environments for SUDs are likely risk factors for COVID-19. The pandemic, in turn, diminishes resources that people with SUD need for their recovery and well-being. This article presents an interdisciplinary and international perspective on how COVID-19 and the related systemic shock impact on individuals with SUDs directly and indirectly. We highlight a need to understand SUDs as biopsychosocial disorders and use evidence-based policies to destigmatize SUDs. We recommend a suite of multi-sectorial actions and strategies to strengthen, modernize and complement addiction care systems which will become resilient and responsive to future systemic shocks similar to the COVID-19 pandemic.

Community-based service requests and utilization among pregnant women incarcerated in jail.

Pregnant incarcerated women represent a unique population in the criminal justice system that has been largely overlooked in terms of their service-related needs. The present study examines 241 pregnant incarcerated women's service requests and preincarceration service utilization related to material help (e.g., food, housing), mental health (e.g., counseling), family services (e.g., home-visiting nurses), and health care (e.g., insurance). A subsample (n = 74) also provided information about service utilization following their release from jail. Analyses examined request and utilization patterns in relation to other sociodemographic risk experiences. Results show that specific risk factors such as age, as well as the accumulation of multiple risk factors, served as barriers to requesting and accessing community-based services. The present study illuminates unique challenges pregnant incarcerated women experience requesting and utilizing services. The results support the use of a gender-responsive, trauma-informed approach to better address the needs of these women. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Infants' brain responses to pupillary changes in others are affected by race.

Sensitive responding to eye cues plays a key role during human social interactions. Observed changes in pupillary size provide a range of socially-relevant information including cues regarding a person's emotional and arousal states. Recently, infants have been found to mimic observed pupillary changes in others, instantiating a foundational mechanism for eye-based social communication. Among adults, perception of pupillary changes is affected by race. Here, we examined whether and how race impacts the neural processing of others' pupillary changes in early ontogeny. We measured 9-month-old infants' brain responses to dilating and constricting pupils in the context of viewing own-race and other-race eyes using functional near-infrared spectroscopy (fNIRS). Our results show that only when responding to own-race eyes, infants' brains distinguished between changes in pupillary size. Specifically, infants showed enhanced responses in the right superior temporal cortex when observing own-race pupil dilation. Moreover, when processing other-race pupillary changes, infants recruited the dorsolateral prefrontal cortex, a brain region linked to cognitive control functions. These findings suggest that, early in development, the fundamental process of responding to pupillary changes is impacted by race and interracial interactions may afford greater cognitive control or effort. This critically informs our understanding of the early origins of responding to pupillary signals in others and further highlights the impact of race on the processing of social signals.

A primer on investigating the role of the microbiome in brain and cognitive development.

Incorporating information regarding the gut microbiota into psychobiological research promises to shed new light on how individual differences in brain and cognitive development emerge. However, the investigation of the gut-brain axis in development is still in its infancy and poses several challenges, including data analysis. Considering that the gut microbiome is an eco-system containing millions of bacteria, one needs to utilize a breadth of methodologies and data analytic techniques. The present review serves two purposes. First, this review will inform developmental psychobiology researchers about the emerging study of the gut-brain axis in development and second, this review will propose methodologies and data analytic strategies for integrating microbiome data in developmental research.