Developmental cascades from maternal preconception stress to child behavior problems: Testing multilevel preconception, prenatal, and postnatal influences.

Although maternal stress during pregnancy and even before conception shapes offspring risk for mental health problems, relatively little is known about the mechanisms through which these associations operate. In theory, preconception and prenatal stress may affect offspring mental health by influencing child responses to postnatal caregiving. To address this knowledge gap, this study had two aims. First, we examined associations between preconception and prenatal stress with child temperament profiles at age four using multilevel assessment of maternal perceived stress and stress physiology. Second, we tested child temperament profiles as moderators of associations between observed parenting behaviors during a parent-child free-play interaction when children were 4 years old and child behavior problems 1 year later. Latent profile analyses yielded four distinct child temperament profiles: inhibited, exuberant, regulated low reactive, and regulated high reactive. Consistent with hypotheses, preconception, and prenatal stress each independently predicted the likelihood of children having temperament profiles characterized by higher negative emotionality and lower regulation. Specifically, preconception perceived stress and prenatal cortisol predicted likelihood of children having an exuberant temperament, whereas prenatal perceived stress predicted likelihood of children having an inhibited temperament. Contrary to hypotheses, temperament profiles did not moderate predictions of child behavior problems from observed parenting behaviors; however, responsive parenting behaviors inversely predicted child behavior problems independently of child temperament. These findings add to growing evidence regarding effects of preconception factors on child outcomes and underscore a central role for responsive parenting behaviors in predicting more favorable child mental health independent of child temperament. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Integrating Biobehavioral and Environmental Components of Developmental Psychopathology via Interpersonal Dynamics: An RDoC-Advancing Model.

Although the Research Diagnostic Criteria (RDoC) framework proposes biological and environmental mechanisms intersect in the etiology of psychopathology, there is no guidance on how to define or measure experiences in the environment within the RDoC matrix. Interpersonal dynamics during caregiver-child interactions involve temporal coordination of interacting partners' biobehavioral functioning; repeated experiences of signaling to caregivers and responding to caregivers' signals shape children's subsequent socioemotional and brain development. We begin with a review of the extant literature on caregiver-child dynamics, which reveals that RDoC's units of analysis (brain circuits, physiology, behavior, and self-report) are inextricably linked with moment-to-moment changes in the caregiving environment. We then offer a proof-of-concept for integrating biobehavioral RDoC units and environmental components via caregiver-child dynamics. Our approach uses dynamic structural equation models to estimate within-dyad dynamics involving arousal, social, cognitive, and negative or positive affective processes based on second-by-second changes in parasympathetic activity (RSA) during a conflict discussion and a positive event-planning task. Our results illustrate variation in parent-child RSA synchrony, suggesting differences depending on the driver (i.e., child- or parent-led) and on the unique and intersecting domains involved (e.g., positive or negative affect valence systems). We conclude with recommendations for conducting robust, methodologically rigorous studies of interpersonal dynamics that advance the RDoC framework and provide a summary of the clinical implications of this research. Examining caregiver-child dynamics during and across multiple dyadic interaction paradigms that differentially elicit key domains of functioning can deepen understanding of how caregiver- and child-led interpersonal dynamics contribute to child psychopathology risk.

Resilience resources, life stressors, and postpartum depressive symptoms in a community sample of low and middle-income Black, Latina, and White mothers.

Resilience resources refer to factors that protect against the physical and mental health effects of stress exposure. This study used a cross-sectional design to test whether three individual-level resilience resources-mastery, self-esteem, and perceived social support-moderated associations between prenatal major life stressors and postpartum depressive symptoms at approximately 8 weeks postpartum. Participants were 2510 low- and middle-income women enrolled after the birth of a baby in a multi-site study of five communities in the United States. At approximately 8 weeks postpartum, participants were interviewed in their homes to assess the three resilience resources, symptoms of depression, and major life stressors that had occurred during the pregnancy. The results of path analyses revealed that mastery and self-esteem moderated the positive association between prenatal life stressors and postpartum depressive symptoms adjusting for race/ethnicity, partner status, years of education, and household income. Perceived social support was associated with fewer postpartum depressive symptoms but did not moderate the association between life stressors and depressive symptoms. Higher levels of two personal resilience resources, mastery and self-esteem, attenuated the association between prenatal life stressors and early postpartum depressive symptoms in a large, predominantly low-income multi-site community sample. These findings highlight the protective nature of individual-level resilience resources in the early postpartum period when maternal adjustment shapes parent and child health outcomes.

Antecedents and Consequences of Child Externalizing Problems: Differences in Dynamic Parent-Child Processes.

Given that noncompliance is the most common externalizing problem during middle childhood and reliably predicts significant conduct problems, innovations in elucidating its etiology are sorely needed. Evaluation of in-the-moment antecedents and consequences of child noncompliance improves traction on this goal, given that multiple theories contend that child noncompliance and parent behavior mutually influence each other through negative reciprocation as well as contingent praise processes. Among a sample of 140 families (child age: 6-10 years; 32.1% female), the present study capitalized on intensive repeated measures of observed child noncompliance and parent negative talk and praise objectively coded during three unique tasks. We employed dynamic structural equation modeling to evaluate within-dyad parent-child behavioral dynamics and between-dyad differences therein. Results provided mixed support for hypotheses and suggested that antecedents and consequences of child noncompliance differed according to task demands and child ADHD symptoms. Contrary to models of coercive cycles, during child-led play, parent negative talk was more likely following prior child noncompliance, but child noncompliance was less likely following prior parent negative talk. As expected, during parent-led play, parent praise was less likely following prior child noncompliance, which was also less likely following prior parent praise. Relative to youth with fewer symptoms, for children with elevated ADHD symptoms, during a challenging clean-up task, child noncompliance was less stable and less contingent on prior parent negative talk. Results are discussed in terms of their implications of real-time parent-child interactions for typical and atypical development of externalizing problems.

Dynamic structural equation models with binary and ordinal outcomes in Mplus.

Intensive longitudinal designs are increasingly popular, as are dynamic structural equation models (DSEM) to accommodate unique features of these designs. Many helpful resources on DSEM exist, though they focus on continuous outcomes while categorical outcomes are omitted, briefly mentioned, or considered as a straightforward extension. This viewpoint regarding categorical outcomes is not unwarranted for technical audiences, but there are non-trivial nuances in model building and interpretation with categorical outcomes that are not necessarily straightforward for empirical researchers. Furthermore, categorical outcomes are common given that binary behavioral indicators or Likert responses are frequently solicited as low-burden variables to discourage participant non-response. This tutorial paper is therefore dedicated to providing an accessible treatment of DSEM in Mplus exclusively for categorical outcomes. We cover the general probit model whereby the raw categorical responses are assumed to come from an underlying normal process. We cover probit DSEM and expound why existing treatments have considered categorical outcomes as a straightforward extension of the continuous case. Data from a motivating ecological momentary assessment study with a binary outcome are used to demonstrate an unconditional model, a model with disaggregated covariates, and a model for data with a time trend. We provide annotated Mplus code for these models and discuss interpretation of the results. We then discuss model specification and interpretation in the case of an ordinal outcome and provide an example to highlight differences between ordinal and binary outcomes. We conclude with a discussion of caveats and extensions.

A dynamic perspective on depressive symptoms during the first year postpartum.

The current study used novel methodology to characterize intraindividual variability in the experience of dynamic, within-person changes in postpartum depressive (PPD) symptoms across the first year postpartum and evaluated maternal and infant characteristics as predictors of between-person differences in intraindividual variability in PPD symptoms over time. With a sample of 322 low-income Mexican-origin mothers (Mage = 27.79; SD = 6.48), PPD symptoms were assessed at 11 time points from 3 weeks to 1 year postpartum (Edinburgh Perinatal Depression Scale; Cox & Holden, 2003). A prenatal cumulative risk index was calculated from individual psychosocial risk factors. Infant temperamental negativity was assessed via a maternal report at the infant age of 6 weeks (Infant Behavior Questionnaire; Putnam et al., 2014). Multilevel location scale analyses in a dynamic structural equation modeling (Asparouhov et al., 2018) framework were conducted. Covariates included prenatal depressive symptoms. On average, within-mother change in depressive symptoms at one time point was found to carry over to the next time point. Nonnull within-mother volatility in PPD symptoms reflected substantial ebbs and flows in PPD symptoms over the first year postpartum. Results of the between-level model demonstrated that mothers differed in their equilibriums, carryover, and volatility of their PPD symptoms. Mothers with more negative infants and those with higher prenatal cumulative risk exhibited higher equilibriums of PPD symptoms and more volatility in symptoms but did not differ in their carryover of PPD symptoms. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Within-dyad bidirectional relations among maternal depressive symptoms and child behavior problems from infancy through preschool.

Although dyadic theory focuses on the impact of a mother's mental health on her own child and the impact of a child's mental health on their own mother, commonly used statistical approaches are incapable of distinguishing the desired within-dyad processes from between-dyad effects. Using autoregressive latent trajectory modeling with structured residuals, the current study evaluated within-dyad, bidirectional associations between maternal depressive symptoms and child behavior problems from child age 1-4.5 years among a sample of low-income, Mexican American women (N = 322, Mage = 27.8) and their children. Women reported on maternal depressive symptoms and child behavior problems during laboratory visits at child age 1, 1.5, 2, 3, and 4.5 years. Results provide novel evidence of child-driven bidirectional association between maternal depressive symptoms and child behavior problems at the within-dyad level as early as child age 1 year and within-person stability in child behavior problems emerging early in life.

Maternal Early Life Adversity and Infant Stress Regulation: Intergenerational Associations and Mediation by Maternal Prenatal Mental Health.

Early life adversity is a potent risk factor for poor mental health outcomes across the lifespan, including offspring vulnerability to psychopathology. Developmentally, the prenatal period is a sensitive window in which maternal early life experiences may influence offspring outcomes and demarcates a time when expectant mothers and offspring are more susceptible to stressful and salutary influences. This prenatal plasticity constituted the focus of the current study where we tested the association of maternal early life adversity with infant stress regulation through maternal prenatal internalizing symptoms and moderation by prenatal social support. Mother-infant dyads (n = 162) were followed prospectively and mothers completed assessments of social support and depressive and anxiety symptoms across pregnancy. Infants completed standardized stress paradigms at one month and six months. There were several key findings. First, maternal prenatal depressive symptoms significantly mediated predictions of infant cortisol reactivity to the heel stick at one month from maternal early life adversity: specifically, maternal early life adversity positively predicted depressive symptoms in pregnancy, which in turn predicted dampened infant cortisol reactivity. Second, prenatal social support did not significantly moderate predictions of depressive or anxiety symptoms in pregnancy from maternal early life adversity nor did it alter the associations of maternal depressive or anxiety symptoms with infant stress regulation. These results suggest that maternal prenatal mental health is a key mechanism by which maternal early life adverse experiences affect offspring risk for psychopathology. We discuss potential clinical and health implications of dysregulated infant cortisol reactivity with respect to lifespan development.

Sometimes "we" can help: parents' pronoun use buffers fear and anxiety transmission.

BACKGROUND AND OBJECTIVES: Parents' natural language when describing health-related threats reflects parents' cognitions that may shape their transmission of anxiety and fear. Parents' greater communal focus (i.e., higher we-talk) and less self-focus (i.e., lower I-talk) may buffer against intergenerational fear/anxiety transmission. The current study investigated whether the relation between parents' and children's anxiety and pandemic-related fear differed by parent we- and I-talk. DESIGN AND METHODS: Parents of 114 children (2-19 years; M = 9.75, SD = 3.73) completed online measures assessing children's and parents' anxiety and COVID-19-related fears, and engaged in a written reflection on their early pandemic experiences. The proportion of parents' we-talk and I-talk during the reflection was obtained using Linguistic Inquiry Word Count software. RESULTS: Results of multilevel structural equation models were partially consistent with expectations: The protective effect of we-talk was only observed for parents with lower fear/anxiety. For parents with higher fear/anxiety, higher I-talk was associated with lower child fear/anxiety. At higher levels of parent we-talk and at lower levels of I-talk, there was an unexpectedly positive association between parents' and children's fear/anxiety. CONCLUSIONS: The concordance between parents' and their children's fear/anxiety differs depending on parents' natural language when reflecting on the pandemic.

Increases in maternal depressive symptoms during pregnancy and infant cortisol reactivity: Mediation by placental corticotropin-releasing hormone.

BACKGROUND: Maternal depressive symptoms in pregnancy may affect offspring health through prenatal programming of the hypothalamic-pituitary-adrenal (HPA) axis. The biological mechanisms that explain the associations between maternal prenatal depressive symptoms and offspring HPA axis regulation are not yet clear. This pre-registered investigation examines whether patterns of maternal depressive symptoms in pregnancy are associated with infant cortisol reactivity and whether this association is mediated by changes in placental corticotropin-releasing hormone (pCRH). METHOD: A sample of 174 pregnant women completed assessments in early, mid, and late pregnancy that included standardized measures of depressive symptoms and blood samples for pCRH. Infant cortisol reactivity was assessed at 1 and 6 months of age. RESULTS: Greater increases in maternal depressive symptoms in pregnancy were associated with higher cortisol infant cortisol reactivity at 1 and 6 months. Greater increases in maternal depressive symptoms in pregnancy were associated with greater increases in pCRH from early to late pregnancy which in turn were associated with higher infant cortisol reactivity. CONCLUSIONS: Increases in maternal depressive symptoms and pCRH over pregnancy may contribute to higher infant cortisol reactivity. These findings help to elucidate the prenatal biopsychosocial processes contributing to offspring HPA axis regulation early in development.

Prenatal Programming of Behavior Problems via Second-by-Second Infant Emotion Dynamics.

Fetal adaptations to prenatal maternal stress may confer high risk for childhood behavior problems, potentially operating via dynamic fluctuations in infants' emotions during mother-infant interactions. These fluctuations over time may give rise to behavior problems. Among a sample of 210 low-income mothers of Mexican origin and their 24-week-old infants, dynamic structural equation modeling was used to examine whether within-infant second-by-second emotion processes were predicted by maternal prenatal stress and predicted behavior problems at 36 and 54 months. The mean level around which infant negative affect fluctuated was related to prenatal stress, but not to childhood behavior problems. The volatility in infant negative affect, reflecting greater ebb and flow in infant negative affect during playful interaction, was predicted by prenatal stress and predicted enduring behavior problems in childhood. Results highlight a potential child-driven pathway linking prenatal exposure with childhood behavior problems via infant negative emotional volatility.

Pregnancy anxiety, placental corticotropin-releasing hormone and length of gestation.

OBJECTIVE: High pregnancy anxiety is a consistent predictor of earlier labor and delivery. Placental corticotropin-releasing hormone (pCRH) predicts earlier delivery consistently and it has been identified as a biological mediator of the association between pregnancy anxiety and gestational length. However, studies have not examined whether changes in pregnancy anxiety are associated with earlier birth as mediated by changes in pCRH during pregnancy. Accordingly, this study tests whether linear changes in pregnancy anxiety are associated with length of gestation indirectly through nonlinear increases in pCRH over pregnancy. METHODS: A sample of pregnant women (n=233) completed prenatal assessments in early pregnancy, second trimester, and third trimester that included a 4-item assessment of pregnancy anxiety and collection of blood samples assayed for pCRH using radioimmunoassay. Length of gestation was abstracted from medical records after birth. RESULTS: Increases in pregnancy anxiety from early pregnancy to third trimester predicted shorted length of gestation, as did nonlinear increases in pCRH over pregnancy. However, there was no evidence of an indirect effect of changes in pregnancy anxiety on length of gestation via changes in pCRH. CONCLUSIONS: These results indicate that linear changes in pregnancy anxiety and nonlinear changes in pCRH during pregnancy are independent risk factors for shortened gestational length. This study adds to a small but growing body of work on biopsychological processes in pregnancy and length of gestation. Modeling changes in psychological and biological processes during pregnancy could provide more insight into understanding risk for adverse pregnancy outcomes.

Maternal Depressive Symptoms, Paternal Engagement, and Toddler Behavior Problems in Low-income Mexican-origin Families.

OBJECTIVE: Maternal postpartum depression (PPD) may influence fathers' engagement in childrearing; however, empirical studies have been equivocal as to whether these effects emerge in a compensatory (i.e., higher paternal engagement) or spillover (i.e., lower paternal engagement) manner. This study evaluated fathers' gender role attitudes as a moderator that shapes the association between maternal PPD and fathers' engagement during infancy, and also examined relations between father engagement and children's subsequent behavior problems. METHOD: In a prospective study of low-income, Mexican-origin families (N = 181 mothers and a subset of their partners, N = 92 fathers), maternal PPD symptoms and fathers' gender role attitudes were measured at 15-weeks postpartum, father engagement was measured at 21-weeks, and children's behavior problems were measured at 12 and 18 months. RESULTS: Higher maternal PPD symptoms were associated with lower father engagement and more child behavior problems when fathers endorsed more segregated gender role attitudes; however, this relation was not significant when fathers endorsed less segregated, more contemporary gender role attitudes. A mediational chain was evident, wherein the interaction of maternal PPD and fathers' gender role attitudes predicted paternal engagement, and lower paternal engagement subsequently predicted more child behavior problems at 12 months, which predicted more child behavior problems at 18 months. CONCLUSIONS: Results suggest the effects of maternal PPD on children's behavior problems may operate via paternal engagement, which is affected by fathers' traditional gender role attitudes. The study highlights the importance of examining fathering and children's behavior using a cultural-contextual lens among underrepresented ethnic minority families.

Longitudinal associations between early child weight gain, parent feeding, child self-regulation, and later child body mass index.

BACKGROUND: Few longitudinal studies have examined associations of child weight trajectories, maternal demandingness and responsiveness during feeding, and child self-regulation. OBJECTIVE: We examined if child weight-for-length trajectories from 6 weeks to 2 years of age were associated with maternal demandingness and responsiveness at child age 3 years old, and if maternal feeding dimensions predicted child BMI trajectories from 4.5 to 7.5 years among Mexican American children from low-income families. Child self-regulation was evaluated as a potential mechanism linking maternal feeding with child BMI. METHOD: Child (N = 322) weight and length/height were assessed at 10 timepoints from 6 weeks through 7.5 years. Mothers completed the Caregiver Feeding Style Questionnaire when the child was 3 years of age. RESULTS: A steeper slope of weight-for-length z scores from 6 weeks to 2 years (indicating more rapid weight gain) was associated with less maternal demands during feeding at 3 years. More maternal demandingness at child age 3 years predicted lower child BMI at 4.5 years, but not trajectories from 4.5 to 7 years. Child self-regulation was not associated with child BMI from 4.5 to 7.5 years. CONCLUSION: The findings highlight how the relationship between mothers and children during feeding can be bidirectional and potentially influenced by the developmental stage.

Socioemotional Mechanisms of Children's Differential Response to the Effects of Maternal Sensitivity on Child Adjustment.

OBJECTIVE: Children differ in the extent to which they reap the benefits of maternal sensitive care or suffer the adverse consequences of insensitive care, and these differences can be accounted for by biological characteristics. However, how susceptible children adapt to maternal sensitivity in ways that either maximize positive development or lead to maladjustment has yet to be determined. Here, we propose a novel model of socioemotional mechanisms by which the joint influences of maternal sensitivity and child biological characteristics influence child adjustment. DESIGN: We propose a theoretical model, in which children's vagal functioning and polymorphisms in serotonin transporter (5-HTTLPR) and dopamine receptor D4 (DRD4) genes confer susceptibility to the effects of maternal sensitivity on internalizing, externalizing, prosocial and moral behavior via changes in interpersonal strategies for emotion regulation, the threat response system, and empathy. RESULTS: Theoretical and empirical support for the proposed mechanisms are provided. CONCLUSIONS: The proposed mechanistic model of susceptibility to maternal sensitivity offers a novel framework of for whom and how children are affected by early maternal care, highlighting multiple reciprocal, interacting influences across genes, physiology, behavior, and the environment.

Second-by-second infant and mother emotion regulation and coregulation processes.

Context-appropriate infant physiological functioning may support emotion regulation and mother-infant emotion coregulation. Among a sample of 210 low-income Mexican-origin mothers and their 24-week-old infants, dynamic structural equation modeling (DSEM) was used to examine whether within-infant vagal functioning accounted for between-dyad differences in within-dyad second-by-second emotion regulation and coregulation during free play. Vagal functioning was captured by within-infant mean and variability (standard deviation) of respiratory sinus arrhythmia (RSA) during free play. Infant emotion regulation was quantified as emotional equilibria (within-person mean), volatility (within-person deviation from equilibrium), carryover (how quickly equilibrium is restored following a disturbance), and feedback loops (the extent to which prior affect dampens or amplifies subsequent affect) in positive and negative affect during free play; coregulation was quantified as the influence of one partner's affect on the other's subsequent affect. Among infants with lower RSA variability, positive affect fluctuated around a higher equilibrium, and negative affect fluctuated around a lower equilibrium; these infants exhibited feedback loops where their positive affect dampened their subsequent negative affect. As expected, infants with higher mean RSA exhibited more volatility in positive affect, feedback loops between their positive and negative affect, and stronger mother-driven emotion coregulation. The results highlight differences in simultaneously occurring biological and emotion regulation.

Within-mother variability in vagal functioning and concurrent socioemotional dysregulation.

During dyadic interactions, well-regulated autonomic responses may support and be supported by socioemotional regulation, whereas autonomic responses that are inappropriate for the social context may be linked with socioemotional dysregulation. We evaluated women's parasympathetic and socioemotional responses during playful interaction with their 24-week-old infants, hypothesizing that insufficient or excessive variability in second-by-second vagal functioning would be associated with concurrent socioemotional dysregulation. Among a sample of 322 low-income, Mexican origin mothers (Mage  = 27.8; SD = 6.5 years), variability in second-by-second vagal functioning was indexed by within-mother standard deviation (SD) in respiratory sinus arrhythmia (RSA) during a 5-min unstructured play task. A latent construct of socioemotional dysregulation was identified using factor analyses. Structural equation modeling was used to evaluate linear and quadratic relations between within-mother SD of RSA and concurrent socioemotional dysregulation. Analyses revealed a positively accelerated relationship between within-mother SD of RSA and concurrent maternal socioemotional dysregulation during play with her infant. Within-mother SD of RSA during a non-interactive baseline task was not related to maternal dysregulation. The results illustrate mothers' dynamic autonomic and socioemotional responses are intertwined during real-time interactions with her infant and lend support for the discriminant validity of within-mother SD of RSA during free play.

A prenatal programming perspective on the intergenerational transmission of maternal adverse childhood experiences to offspring health problems.

Decades of research indicate that individuals exposed to childhood adversity are at risk for poor physical and mental health across their life span. More recently, intergenerational transmission of trauma and prenatal programming frameworks suggest an even longer reach for adverse childhood experiences (ACEs), with consequences that extend to subsequent generations. Beyond the individual-level consequences typically observed by empirical studies of ACEs, mothers' experiences of early adversity may also compromise the maternal-child dyadic relationship. We propose a conceptual model whereby mothers' ACEs impact maternal-infant dyadic functioning and later biobehavioral health outcomes through heightened perinatal psychosocial risk. We provide support for the proposed paths and mechanistic processes in our model with data drawn from Las Madres Nuevas, a longitudinal study of low-income Mexican-origin families who participated in a series of home and laboratory visits from the prenatal period through early childhood. Higher ACEs exposure among Las Madres Nuevas participants was associated with numerous perinatal psychosocial risk factors, which predicted poorer mother-infant dyadic functioning. Compromised dyadic functioning during infancy was associated with later maternal mental health and child behavior problems. We conclude with discussion of prevention and treatment strategies that can buffer against proposed risk pathways, including perinatal assessment of maternal ACEs and psychosocial risk, perinatal treatment of maternal distress, and mother-infant therapy in the postpartum period. It is our hope that the proposed conceptual model will serve as a guide for future research to examine the lasting consequences of childhood adversities within and across generations among high-risk populations. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Infant Vagal Tone and Maternal Depressive Symptoms: A Bottom-Up Perspective.

Children vary in their susceptibility to environmental exposures such as maternal depression, but little is known about how children shape those same environments. When raising an infant with low arousal, mothers at risk of depression may experience decreased parenting self-efficacy and increased depressive symptoms. We evaluated a longitudinal mediated moderation model that hypothesized interactive effects of infant vagal tone (indexed by respiratory sinus arrhythmia [RSA]) and maternal postpartum depressive (PPD) symptoms on maternal depressive symptoms in early childhood via parenting self-efficacy. Among a sample of 322 very low-income Mexican American mother-infant dyads (46% male infants), infant RSA was assessed at 6 weeks of age; mothers (Mage = 27.8, SD = 6.5) reported PPD symptoms every 3 weeks from 6 weeks to 6 months, parenting self-efficacy at 18 and 24 months, and depressive symptoms at 18 and 36 months. Higher PPD symptoms predicted higher maternal depressive symptoms at 36 months, especially among mothers whose infants had lower resting RSA. The interactive effect of PPD symptoms and infant RSA on 36-month depressive symptoms was partially mediated by lower parenting self-efficacy. Lower infant RSA may exacerbate the detrimental effects of PPD symptoms on subsequent maternal well-being via damage to mothers' beliefs in their ability to parent effectively.

Quantifying the dynamic nature of vagal responsivity in infancy: Methodological innovations and theoretical implications.

According to polyvagal theory, rapid modulation of the vagal brake develops early in infancy and supports social interactions. Despite being viewed as a dynamic system, researchers typically assess vagal regulation using global measures of respiratory sinus arrhythmia (RSA; an index of vagal tone). This study sought to capture the dynamic property of RSA and evaluate individual differences in within-infant RSA responsivity during mother-infant interaction. RSA was evaluated in a sample of 135 6-month-old Mexican-American infants during a 5-min free play task. Mothers reported on their children's behavioral problems and competence at 18 months using the Brief Infant-Toddler Social and Emotional Assessment. Time-varying estimates of infant RSA during the interaction were obtained using a multiple window technique and spectrogram analysis. Using structural equation modeling, we evaluated whether within-infant SD of RSA predicted infants' behavioral problems and competence at 18 months, after adjusting for infants' mean RSA and covariates. Greater within-infant SD of RSA predicted more behavior problems at 18 months. This study demonstrates that assessing intra-individual variability in RSA, or the extent to which infants fluctuate around their average level of RSA during a task, enhances our ability to test polyvagal theory's central tenet: vagal regulation supports well-regulated social interaction.