Socioeconomic risk moderates the association between caregiver cortisol levels and infant cortisol reactivity to emotion induction at 24 months

Distinct trajectories of caregiver-toddler physiological attunement during routine vaccinations

Introduction

Toddlers rely on their caregivers for regulatory support when faced with pain-related distress. The caregiver's ability to support their toddler relies on their capacity to regulate their own distress and respond effectively to the child's need for support. The aim of the current study was to describe patterns of caregiver-toddler physiological co-regulatory patterns, also known as attunement, during routine vaccinations across the second year of life.

Methods

Caregiver-toddler dyads (N = 189) were part of a longitudinal cohort observed at either 12-, 18-, or 24-month well-baby vaccinations. Parallel-process growth-mixture modeling was used to examine patterns of dyadic physiological co-regulatory responses, indexed by high-frequency heart rate variability (HF-HRV).

Results

Three groups of dyads were discerned. The largest group (approximately 80%) demonstrated physiological attunement, with a stable and parallel regulatory pattern of HF-HRV from baseline to postneedle. The second group (7.9%) had parallel regulatory trajectories but with notably lower (ie, less regulated) HF-HRV values, which indicates independent regulatory responses (ie, a lack of attunement among dyad members). The third group (11.1%) showed diverging regulatory trajectories: Caregivers showed a stable regulatory trajectory, but toddlers demonstrated a steep decrease followed by an increase in HF-HRV values that surpassed their baseline levels by the third minute postneedle. Post hoc analyses with the HF-HRV groupings explored heart rate patterns and potential predictors.

Conclusions

These findings elucidate potential adaptive and maladaptive co-regulatory parasympathetic patterns in an acute pain context.

Transactional associations between infant negative emotionality and maternal sensitivity: Maternal emotion dysregulation as a moderator

The relations between maternal sensitivity and infant negative emotionality have been tested extensively in the previous literature. However, the extent to which these associations reflect unidirectional or bidirectional effects over time remains somewhat uncertain. Further, the possibility that maternal characteristics moderate the extent to which infant negative emotionality predicts maternal sensitivity over time has yet to be tested in cross-lag models. The goal of the present study is to address these gaps. First time mothers (N = 259; 50% White; 50% Black) and their infants participated when infants were 6, 14, and 26 months of age. Infant negative emotionality was assessed via maternal report and direct observation during standardized laboratory tasks, which were subsequently combined to yield a multimethod measure at each wave. Maternal sensitivity was observationally coded at each wave and mothers self-reported emotion dysregulation at 6 and 14 months. A random intercepts cross-lagged model with maternal emotion dysregulation specified as a moderator revealed that infant negative emotionality at 6 months was negatively associated with maternal sensitivity at 14 months, but only among mothers higher in emotion dysregulation. Higher maternal sensitivity was in turn associated with lower infant negative emotionality when infants were 26 months of age. The indirect pathway was significant, lending support for the transactional model. Implications for future research and prevention/intervention are discussed. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Household Social Needs, Emotional Functioning, and Stress in Low-Income Latinx Children and their Mothers

Latinx families may be particularly vulnerable to emotional dysfunction, due to higher rates of economic hardship and complex social influences in this population. Little is known about the impact of environmental stressors such as unmet social needs and maternal stress on the emotional health of Latinx children from low-income families. We conducted secondary analyses using survey and biomarker data from 432 Latinx children and mothers collected in a separate study. We used binomial and multinomial logistic regression to test if household social needs, or maternal perceived stress or hair cortisol concentration (HCC), predicted child measures of emotional functioning or child HCC, independent of relevant sociodemographic factors. Approximately 40% of children in the sample had symptoms consistent with emotional dysfunction, and over 37% of households reported five or more social needs. High perceived maternal stress predicted higher odds of child emotional dysfunction (OR = 2.15; 95% CI [1.14, 4.04]; p = 0.01), and high maternal HCC was positively associated with high child HCC (OR = 10.60; 95% CI [4.20, 26.74]; p < 0.01). Most individual household social needs, as well as the level of household social need, were not independently associated with child emotional dysfunction or child HCC. Our findings begin to define a framework for understanding emotional health, stress, and resilience when caring for Latinx children and mothers living with high levels of social need, and the need for integrated mental health and social needs screening and interventions in settings that serve this population.

Cortisol reactivity and negative affect among preterm infants at 12 months during a mother-infant interaction task

The purpose of this study was to investigate correlates of preterm (PT) infant's cortisol reactivity and the association to infant negative affect, during a mother-infant interaction procedure. Participants included 48 infants born prematurely (gestational age < 37 weeks) and their mothers, assessed when infants were 12 months old corrected for prematurity. The examined variables comprised both neonatal and environmental dimensions including maternal interactive behavior. Infant negative affect and maternal interactive behavior were assessed with a standardized mother-infant interaction task. A baseline infant saliva sample was collected before the interaction began, and a second sample after the interaction episodes ended. Results revealed that decrease of infant's cortisol concentration was significantly associated with the exposure to more sensitive, and less intrusive maternal behaviors. However, once controlled for neonatal risk, family SES and maternal psychological distress, the associations were rendered non-significant. Although the association between cortisol reactivity and negative affect trended toward significance, maternal intrusiveness was the only significant predictor of observed infant negative affect. Findings suggest the importance of primary relational experiences on PT infants' early regulatory competencies.

Unmet Social Needs and Patterns of Hair Cortisol Concentration in Mother-Child Dyads

Background

Mothers and their children demonstrate dyadic synchrony of hypothalamic-pituitary-adrenal (HPA) axis function, likely influenced by shared genetic or environmental factors. Although evidence has shown that chronic stress exposure has physiologic consequences for individuals-including on the HPA axis-minimal research has explored how unmet social needs such as food and housing instability may be associated with chronic stress and HPA axis synchrony in mother-child dyads.

Methods

We conducted a secondary analysis of data from 364 mother-child dyads with low-income recruited during a randomized trial conducted in an urban pediatric clinic. We used latent profile analysis (LPA) to identify subgroups based on naturally occurring patterns of within-dyad hair cortisol concentration (HCC). A logistic regression model predicted dyadic HCC profile membership as a function of summative count of survey-reported unmet social needs, controlling for demographic and health covariates.

Results

LPA of HCC data from dyads revealed a 2-profile model as the best fit. Comparisons of log HCC for mothers and children in each profile group resulted in significantly "higher dyadic HCC" versus "lower dyadic HCC" profiles (median log HCC for mothers: 4.64 vs 1.58; children: 5.92 vs 2.79, respectively; P < .001). In the fully adjusted model, each one-unit increase in number of unmet social needs predicted significantly higher odds of membership in the higher dyadic HCC profile when compared to the lower dyadic HCC profile (odds ratio  =  1.13; 95% confidence interval [1.04-1.23]; P  =  .01).

Conclusion

Mother-child dyads experience synchronous patterns of physiologic stress, and an increasing number of unmet social needs is associated with a profile of higher dyadic HCC. Interventions aimed at decreasing family-level unmet social needs or maternal stress are, therefore, likely to affect pediatric stress and related health inequities; efforts to address pediatric stress similarly may affect maternal stress and related health inequities. Future research should explore the measures and methods needed to understand the impact of unmet social needs and stress on family dyads.

Caregiver and Young Child Biological Attunement In Distress Contexts: A Systematic Review and Narrative Synthesis

The objective of the current study was to systematically review the literature on caregiver-child biological attunement within distress contexts during the first three years of life. A total of 9932 unique abstracts were identified through Medline, Embase, PsycINFO, CINAHL, and Scopus databases. Thirty-six studies provided data from caregivers and their infants or toddlers within a distress paradigm, used biological indicators of distress, and assessed the relations between caregiver and child biological indicators. Findings were synthesized based on biological indicators, type of analysis, and measurement epochs pre- and post-distress. Most articles examined cortisol. Associations between caregiver and child cortisol indicators were moderate to large, though findings varied depending on the analysis used and measurement epochs examined. Many of the findings examining relations between mother and child cardiac, sAA, and EEG indicators were weak or inconsistent, likely due to the limitations of methodological approaches used to capture the complexity of the caregiver-child attunement process. Gaps in the literature and suggestions for future research are discussed.

Parental Education and Left Lateral Orbitofrontal Cortical Activity during N-Back Task: An fMRI Study of American Adolescents

Introduction. The Orbitofrontal Cortex (OFC) is a cortical structure that has implications in cognition, memory, reward anticipation, outcome evaluation, decision making, and learning. As such, OFC activity correlates with these cognitive brain abilities. Despite research suggesting race and socioeconomic status (SES) indicators such as parental education may be associated with OFC activity, limited knowledge exists on multiplicative effects of race and parental education on OFC activity and associated cognitive ability. Purpose. Using functional brain imaging data from the Adolescent Brain Cognitive Development (ABCD) study, we tested the multiplicative effects of race and parental education on left lateral OFC activity during an N-Back task. In our study, we used a sociological rather than biological theory that conceptualizes race and SES as proxies of access to the opportunity structure and exposure to social adversities rather than innate and non-modifiable brain differences. We explored racial variation in the effect of parental educational attainment, a primary indicator of SES, on left lateral OFC activity during an N-Back task between Black and White 9–10 years old adolescents. Methods. The ABCD study is a national, landmark, multi-center brain imaging investigation of American adolescents. The total sample was 4290 9–10 years old Black or White adolescents. The independent variables were SES indicators, namely family income, parental education, and neighborhood income. The primary outcome was the average beta weight for N-Back (2 back versus 0 back contrast) in ASEG ROI left OFC activity, measured by functional Magnetic Resonance Imaging (fMRI) during an N-Back task. Ethnicity, age, sex, subjective SES, and family structure were the study covariates. For data analysis, we used linear regression models. Results. In White but not Black adolescents, parental education was associated with higher left lateral OFC activity during the N-Back task. In the pooled sample, we found a significant interaction between race and parental education on the outcome, suggesting that high parental education is associated with a larger increase in left OFC activity of White than Black adolescents. Conclusions. For American adolescents, race and SES jointly influence left lateral OFC activity correlated with cognition, memory, decision making, and learning. Given the central role of left lateral OFC activity in learning and memory, our finding calls for additional research on contextual factors that reduce the gain of SES for Black adolescents. Cognitive inequalities are not merely due to the additive effects of race and SES but also its multiplicative effects.

Cortisol and socioeconomic status in early childhood: A multidimensional assessment

The hypothalamic-pituitary-adrenal (HPA) axis is sensitive to early life stress, with enduring consequences for biological stress vulnerability and health (Gunnar & Talge, 2008). Low socioeconomic status (SES) is associated with dysregulation of the stress hormone cortisol in early childhood. However, a mechanistic understanding of this association is lacking. Multidimensional assessment of both SES and cortisol is needed to characterize the intricate relations between SES and cortisol function in early childhood. We assessed parent-reported family income, parent education, occupational prestige, neighborhood risk, food insecurity, and household chaos for 12-month-old infants (N = 90) and 3.5-year-old children (N = 91). Hair cortisol concentration (HCC) was obtained from parent and child, indexing chronic biological stress, and diurnal salivary cortisol was measured in the children. Controlling for parent HCC, parent education uniquely predicted infant and child HCC and, in addition, neighborhood risk uniquely predicted infant HCC. Household chaos predicted bedtime salivary cortisol concentration (SCC) for both infants and children, and infant daily cortisol output. Food insecurity was associated with flattened cortisol slope in 3.5-year-old children. Parental sensitivity did not mediate relations between SES and cortisol. Results highlight the utility of SES measures that index unpredictable and unsafe contexts, such as neighborhood risk, food insecurity, and household chaos.

Elevated infant cortisol is necessary but not sufficient for transmission of environmental risk to infant social development: Cross-species evidence of mother-infant physiological social transmission

Environmental adversity increases child susceptibility to disrupted developmental outcomes, but the mechanisms by which adversity can shape development remain unclear. A translational cross-species approach was used to examine stress-mediated pathways by which poverty-related adversity can influence infant social development. Findings from a longitudinal sample of low-income mother-infant dyads indicated that infant cortisol (CORT) on its own did not mediate relations between early-life scarcity-adversity exposure and later infant behavior in a mother-child interaction task. However, maternal CORT through infant CORT served as a mediating pathway, even when controlling for parenting behavior. Findings using a rodent "scarcity-adversity" model indicated that pharmacologically blocking pup corticosterone (CORT, rodent equivalent to cortisol) in the presence of a stressed mother causally prevented social transmission of scarcity-adversity effects on pup social behavior. Furthermore, pharmacologically increasing pup CORT without the mother present was not sufficient to disrupt pup social behavior. Integration of our cross-species results suggests that elevated infant CORT may be necessary, but without elevated caregiver CORT, may not be sufficient in mediating the effects of environmental adversity on development. These findings underscore the importance of considering infant stress physiology in relation to the broader social context, including caregiver stress physiology, in research and interventional efforts.

Disentangling levels of mother-infant neuroendocrine attunement and longitudinal relations with maternal risk and protective factors

Scientific understanding of mother-infant HPA axis attunement has been limited by discrepant methods for assessing attunement that often conflate different levels of association. We sought to refine the conceptualization of attunement by investigating whether mother-infant cortisol attunement exists as coupling of response trajectories within an acute stress episode, separate from shared developmental patterns and/or overall dyadic similarity in cortisol levels, and whether the degree of attunement depends on within- or between-dyad differences in maternal risk and protective factors. We examined these questions using a longitudinal study with mother/infant salivary cortisol during dyadic stressors at 6, 12, and 18 months postnatal. A three-level hierarchical linear model showed that sample-wide associations between mother and infant cortisol were not significant at any level, suggesting normative lack of attunement; however, there was significant variability in degree of attunement across dyads. Concurrent levels of family resources and social support satisfaction predicted lower mother-infant cortisol attunement within the session, and overall (mean) parenting stress predicted the opposite. Follow-up analyses showed this was typically due to an increase in infants' (but not their mothers') within-session cortisol response slopes with increasing support and decreasing stress. Implications for the role of mother-infant cortisol attunement in intergenerational stress transmission are discussed.