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

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).

Dynamics of mother-infant parasympathetic regulation during face-to-face interaction: The role of maternal emotion dysregulation

The dynamics of parent-infant physiology are essential for understanding how biological substrates of emotion regulation are organized during infancy. Although parent-infant physiological processes are dyadic in nature, research is limited in understanding how one person's physiological responses predict one's own and as well as the other person's responses in the subsequent moment. In this study, we examined mother-infant respiratory sinus arrhythmia (RSA) dynamics during the Still-Face Paradigm (SFP) among 106 mothers (M_age  = 29.54) and their 7-month-old infants (55 males). Given mothers' role in shaping dyadic interactions with their infant, we also tested how mothers' self-reported emotion dysregulation (measured via the Difficulties in Emotion Regulation Scale) associated with these dynamics. Results showed that both mothers' and infants' RSA tended to return to their respective homeostatic points (i.e., exhibited return strength) during each SFP episode, indicating stability in RSA for mother-infant dyads. Significant shifts in mother and infant RSA return strength were observed across SFP episodes, highlighting the role of contextual demands on each individual's physiological dynamics. Mother-infant RSA dynamics varied as a function of maternal self-reported emotion dysregulation. Specifically, RSA levels of infants with more dysregulated mothers had a weaker tendency to return to homeostasis during the Reunion episode and were less affected by their mothers' RSA during the Still-Face and Reunion episodes of the SFP, suggesting a less effective coregulatory influence. Our findings have implications for the intergenerational transmission of emotion dysregulation via mother-infant physiological dynamics.

Long-term effects of a prenatal mindfulness intervention on depressive symptoms in a diverse sample of women

OBJECTIVE

Depression is a public health crisis, and scalable, affordable interventions are needed. Although many psychosocial interventions are effective, there is little research investigating their sustained, long-term influence on well-being. The purpose of this study was to examine whether a prenatal mindfulness intervention with demonstrated benefit for women's depressive symptoms during the early postpartum period would exert effects through 8 years.

METHOD

The sample of 162 lower income women was racially and ethnically diverse. Women were assigned to receive an 8-week mindfulness-based intervention during pregnancy (MIND) or treatment as usual (TAU). Repeated assessments of depressive symptoms were collected using the Patient Health Questionnaire-9 at baseline, postintervention, and following childbirth (1, 2, 3-4, 5, 6, and 8 years from baseline). The most recent assessment of depressive symptoms was collected during the COVID-19 pandemic.

RESULTS

MIND and TAU women were equivalent on sociodemographic factors and depressive symptoms at baseline. Depressive symptoms at all follow-up assessments through 8 years were significantly lower among women in MIND compared to TAU. The odds of moderate or higher depressive symptoms were greater among TAU compared to MIND women at all time points except the 6-year assessment. By Year 8, 12% of women in MIND reported moderate or more severe depressive symptoms compared to 25% of women in TAU.

CONCLUSIONS

Results suggest the effects of a group-based psychosocial intervention during pregnancy may endure for years, well beyond the initial perinatal period. Investing in prevention and intervention efforts for mental health during pregnancy may have sustained benefits for the well-being of women. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Unique Contributions of Maternal Prenatal and Postnatal Emotion Dysregulation on Infant Respiratory Sinus Arrhythmia

Prenatal intrauterine exposures and postnatal caregiving environments may both shape the development of infant parasympathetic nervous system (PNS) activity. However, the relative contributions of prenatal and postnatal influences on infant respiratory sinus arrhythmia (RSA)-an index of PNS functioning-are relatively unknown. We examined whether prenatal and postnatal maternal emotion dysregulation, a transdiagnostic construct that spans mental health diagnoses, were independently related to infant RSA trajectories during a social stressor, the still-face paradigm. Our sample included 104 mothers and their 7-month-old infants. Maternal emotion dysregulation was measured with the Difficulties in Emotion Regulation Scale during the 3rd trimester of pregnancy and again at a 7-month postpartum laboratory visit. Infant RSA was recorded during the still-face paradigm. Only postnatal maternal emotion dysregulation was associated with infant RSA. Specifically, high postnatal emotion dysregulation was associated with a blunted (i.e., dampened reactivity and recovery) infant RSA response profile. Infant sex did not moderate the associations between maternal emotion dysregulation and infant RSA. Findings suggest that postnatal interventions to promote effective maternal emotion regulation may reduce risk for infants' dysregulated psychophysiological stress responses.

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.

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).

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.

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.