Vagal Flexibility Moderates the Links between Observed Sensitive Caregiving in Infancy and Externalizing Behavior Problems in Middle Childhood

This study explored how patterns of physiological stress reactivity underpin individual differences in sensitivity to early rearing experiences and childhood risk for psychopathology. To examine individual differences in parasympathetic functioning, past research has largely relied on static measures of stress reactivity (i.e., residual and change scores) in infancy which may not adequately capture the dynamic nature of regulation across contexts. Using data from a prospective longitudinal study of 206 children (56% African Americans) and their families, this study addressed these gaps by employing the latent basis growth curve model to characterize the dynamic, non-linear patterns of change in infants' respiratory sinus arrhythmia (i.e., vagal flexibility) across the Face-to-Face Still-Face Paradigm. Furthermore, it investigated whether and how infants' vagal flexibility moderates the links between sensitive parenting, observed during a free play task when children were 6 months of age, and parent-report of children's externalizing problems at 7 years of age. Results of the structural equation models revealed that infants' vagal flexibility moderates the predictive relations between sensitive parenting in infancy and children's later externalizing problems. Simple slope analyses revealed that low vagal flexibility, characterized by less suppression and flatter recovery patterns, exacerbated risk for externalizing psychopathology in the context of insensitive parenting. Children with low vagal flexibility also benefited most from sensitive parenting, as indicated by the lower number of externalizing problems. Findings are interpreted in the light of the biological sensitivity to context model and provide evidence for vagal flexibility as a biomarker of individual's sensitivity to early rearing contexts.

A dynamic systems perspective towards executive function development: Susceptibility at both ends for inhibitory control

In light of the dynamic systems perspective, the current study expanded existing literature by examining the moderating effect of maternal sensitivity on the quadratic association between infant negative reactivity and future executive function development. Using a longitudinal, multimethod design, we addressed executive function development among preschoolers. This study utilized data from the Family Life Project (N = 1292). Infant negative reactivity at 6 months, maternal sensitivity across first 3 years, and executive functions during preschool age were observational assessed. A path model with moderation analyses revealed a U-shaped quadratic association between infant negative reactivity and preschoolers' inhibitory control, only when maternal sensitivity was high. The results suggest that maternal sensitivity may assist infants with both low and high, but not moderate, levels of negative reactivity towards better executive function development. Findings support the ongoing nonlinear person-environment interplay during early years of life.

Biological sensitivity to context as a dyadic construct: An investigation of child-parent RSA synchrony among low-SES youth

Parenting behaviors are significantly linked to youths' behavioral adjustment, an association that is moderated by youths' and parents' self-regulation. The biological sensitivity to context theory suggests that respiratory sinus arrhythmia (RSA) indexes youths' varying susceptibility to rearing contexts. However, self-regulation in the family context is increasingly viewed as a process of "coregulation" that is biologically embedded and involves dynamic Parent×Child interactions. No research thus far has examined physiological synchrony as a dyadic biological context that may moderate associations between parenting behaviors and preadolescent adjustment. Using a two-wave sample of 101 low-socioeconomic status (SES) families (children and caretakers; mean age 10.28 years), we employed multilevel modeling to examine dyadic coregulation during a conflict task, indicated by RSA synchrony, as a moderator of the linkages between observed parenting behaviors and preadolescents' internalizing and externalizing problems. Results showed that high dyadic RSA synchrony resulted in a multiplicative association between parenting and youth adjustment. High dyadic synchrony intensified the relations between parenting behaviors and youth behavior problems, such that in the context of high dyadic synchrony, positive and negative parenting behaviors were associated with decreased and increased behavioral problems, respectively. Parent-child dyadic RSA synchrony is discussed as a potential biomarker of biological sensitivity in youth.

Infants' attachment security and children's self-regulation within and outside the parent-child relationship at kindergarten age: Distinct paths for children varying in anger proneness

Research in developmental psychology has robustly documented positive associations between parent-child attachment security and the child's self-regulation (SR). This study of 102 community mothers, fathers, and infants contributes to that research by examining the role of attachment security, observed at 15 months using the Attachment Q-Set, as a predictor of two distinct aspects of self-regulation at 67 months: executive functioning (SR-EF), observed in abstract Stroop-like tasks (Day/Night & Snow/Grass and Tapping), and parent-related (SR-PR), observed within the context of the parent-child relationship in response to the mother's (SR-MR) and father's (SR-FR) requests and prohibitions. We also examined child anger proneness, observed at 7 months, as a moderator of those associations. In both mother-child and father-child dyads, child security predicted SR-EF; More secure children performed better in executive functioning tasks. In mother-child dyads, security also predicted SR-MR, but the effect was qualified by the interaction of security and anger proneness, such that the effect was significant only for highly anger-prone children. The effect reflected differential susceptibility: Compared with lower-anger peers, highly anger-prone children developed worse SR-MR if their security was low, but they developed better SR-MR if their security was high. The findings highlight the benefits of a nuanced approach to self-regulation, considering child individuality as interacting with security and examining processes in both mother-child and father-child dyads.

Maternal Sensitivity Modulates Child's Parasympathetic Mode and Buffers Sympathetic Activity in a Free Play Situation

Background

Behavioral and physiological (self-)regulation in early life is crucial for the understanding of childhood development and adjustment. The autonomic nervous system (ANS) is a main player in the regulative system and should therefore be modulated by the quality of interactive behavior of the caregiver. We experimentally investigated the ANS response of 18–36-month-old children in response to the quality of maternal behavior during a mother–child-interacting paradigm.

Method

Eighty mothers and their children came to our laboratory and took part in an experimental paradigm, consisting of three episodes: a resting phase (E1), a structured play phase (E2), and a free play situation (E3) between mothers and their child. Children’s and mother’s heart rate (HR), the sympathetic nervous system (SNS) activity via the pre-ejection period (PEP) and the left ventricular ejection time (LVET), and the parasympathetic nervous system (PNS) activity via the respiratory sinus arrhythmia (RSA) were continuously measured by an electrocardiogram. Maternal sensitivity of interactive behavior was assessed by using the Emotional Availability (EA) Scales.

Results

Children of mothers with insensitive behavior had a significantly lower RSA at baseline, showed a lack of RSA withdrawal during structured and free play, and had shorter LVET across all episodes compared to children of sensitive mothers.

Conclusion

Our findings depict the influence of low-quality maternal interaction on the child’s ANS regulation, in calm and more stressful play situations. The overall higher SNS mode with impaired PNS reactivity may negatively influence child’s ANS homoeostasis, which may result in a long-term impact on mental and physical wellbeing. Further, the maternal sensitivity may function as a buffer for the stress response of their child. These results could serve as a basis for the development of appropriate psychoeducational programs for mothers of low sensitivity in their interaction with the child.

Associations between acoustic features of maternal speech and infants' emotion regulation following a social stressor

Caregiver voices may provide cues to mobilize or calm infants. This study examined whether maternal prosody predicted changes in infants' biobehavioral state after the still face, a stressor in which the mother withdraws and reinstates social engagement. Ninety-four dyads participated in the study (infant age 4-8 months). Infants' heart rate and respiratory sinus arrhythmia (measuring cardiac vagal tone) were derived from an electrocardiogram (ECG). Infants' behavioral distress was measured by negative vocalizations, facial expressions, and gaze aversion. Mothers' vocalizations were measured via a composite of spectral analysis and spectro-temporal modulation using a two-dimensional fast Fourier transformation of the audio spectrogram. High values on the maternal prosody composite were associated with decreases in infants' heart rate (β = -.26, 95% CI: [-0.46, -0.05]) and behavioral distress (β = -.23, 95% CI: [-0.42, -0.03]), and increases in cardiac vagal tone in infants whose vagal tone was low during the stressor (1 SD below mean β = .39, 95% CI: [0.06, 0.73]). High infant heart rate predicted increases in the maternal prosody composite (β = .18, 95% CI: [0.03, 0.33]). These results suggest specific vocal acoustic features of speech that are relevant for regulating infants' biobehavioral state and demonstrate mother-infant bi-directional dynamics.

Associations between infant-mother physiological synchrony and 4- and 6-month-old infants' emotion regulation

In this study we assessed whether physiological synchrony between infants and mothers contributes to infants' emotion regulation following a mild social stressor. Infants between 4 and 6 months of age and their mothers were tested in the face-to-face-still-face paradigm and were assessed for behavioral and physiological self-regulation during and following the stressor. Physiological synchrony was calculated from a continuous measure of respiratory sinus arrhythmia (RSA) enabling us to cross-correlate the infants' and mothers' RSA responses. Without considering physiological synchrony, the evidence suggested that infants' distress followed the prototypical pattern of increasing during the Still Face episode and then decreasing during the reunion episode. Once physiological synchrony was added to the model, we observed that infants' emotion regulation improved if mother-infant synchrony was positive, but not if it was negative. This result was qualified further by whether or not infants suppressed their RSA response during the Still Face episode. In sum, these findings highlight how individual differences in infants' physiological responses contribute significantly to their self-regulation abilities.

Chronic early trauma impairs emotion recognition and executive functions in youth; specifying biobehavioral precursors of risk and resilience

Exposure to chronic early trauma carries lasting effects on children's well-being and adaptation. Guided by models on resilience, we assessed the interplay of biological, emotional, cognitive, and relational factors in shaping two regulatory outcomes in trauma-exposed youth: emotion recognition (ER) and executive functions (EF). A unique war-exposed cohort was followed from early childhood to early adolescence. At preadolescence (11-13 years), ER and EF were assessed and respiratory sinus arrhythmia (RSA), biomarker of parasympathetic regulation, was quantified. Mother-child dyadic reciprocity, child's avoidance symptoms, and cortisol (CT) were measured in early childhood. Trauma-exposed youth displayed impaired ER and EF abilities. Conditional process analysis described two differential indirect paths leading from early trauma to regulatory outcomes. ER was mediated by avoidance symptoms in early childhood and modulated by cortisol, such that this path was evident only for preadolescents with high, but not low, CT. In comparison, EF was mediated by the degree of dyadic reciprocity experienced in early childhood and modulated by RSA, observed only among youth with lower RSA. Findings pinpoint trauma-related disruptions to key regulatory support systems in preadolescence as mediated by early-childhood relational, clinical, and physiological factors and highlight the need to specify biobehavioral precursors of resilience toward targeted early interventions.

A Developmental Hierarchical-Integrative Perspective on the Emergence of Self-Regulation: A Replication and Extension

This study replicated and extended the Feldman (2009) study by applying the developmental hierarchical-integrative model to understand the emergence of self-regulation. Participants included 360 children (48.6% boys; 62.8% identified as Caucasian and 36.9% African American) and their families, predominantly from a low-income, rural background. Families completed assessments on child physiological, attention, emotion, and self-regulation when children were 6-, 15-, 24-, and 36-month-old, when caregiver sensitivity was observationally assessed. A path model revealed that child attention regulation at 6 months predicted physiological regulation at 15 months, and child attention regulation at 15 months predicted emotion regulation at 24 months. Attention regulation at 24 months predicted better self-regulation at 36 months. Notably, caregiver sensitivity moderated several developmental pathways. Findings support a continuous model of early self-regulation development and the ongoing individual-environment interplay in early childhood.

Paternal antisociality and growth in child delinquent behaviors: Moderating effects of child sex and respiratory sinus arrhythmia

Children of fathers with antisocial personality disorder (ASPD) are at risk for developing delinquency, and both biological and environmental mechanisms contribute. In this study, we test parasympathetic nervous system (PNS) function as a vulnerability/sensitivity attribute in predicting intergenerational associations between fathers' antisociality and children's delinquency scores. We followed 207 children (ages 8-12 years at intake; 139 boys) across three annual assessments. Fathers' antisociality was measured via maternal reports on the Family Interview for Genetic Studies (FIGS). At Year 1, children's resting respiratory sinus arrhythmia (RSA) was measured. At Years 1, 2, and 3, child delinquent behaviors were assessed using the delinquency subscale of the Youth Self-Report. At age 8, boys' delinquency scores were associated weakly with paternal antisocial behaviors. However, boys' delinquency scores increased steeply thereafter specifically for those who had fathers with higher antisocial symptoms. In addition, associations between delinquency and paternal antisociality were largest for boys with higher resting RSA. For girls, growth in delinquency was unrelated to both father antisociality and resting RSA. These findings (a) suggest moderating effects of children's age, sex, and PNS function on associations between father antisocial behavior and offspring delinquency; and (b) provide insights into differential vulnerability among children of fathers with ASPD.

Towards an understanding of neurophysiological self-regulation in early childhood: A heuristic and a new approach

Self-regulation in early childhood encompasses both "top down," volitional processes, as well as the "bottom up" activity of three neurophysiological systems: the parasympathetic nervous system (PNS), the sympathetic nervous system (SNS), and the hypothalamic-pituitary-adrenal (HPA) axis. In this paper we briefly review the structure, function, and early development of each of these systems and then explain why neurophysiological self-regulation is most accurately defined as a function of their joint activity. We note that while there are a number of predictive models that employ this definition, the field would benefit from a straightforward heuristic and aligned methods of visualization and analysis. We then present one such heuristic, which we call neurophysiological space, and outline how it may facilitate a new, collaborative approach to building a better understanding of self-regulation in early childhood. We conclude with a presentation of early education as one setting in which our heuristic and methods could be applied.

Exploring relationship between self-regulation dimensions and cardiac autonomic functioning in preschoolers

The present study examined the association between behavioural dimensions of self-regulation and respiratory sinus arrhythmia (RSA), a marker of cardiac autonomic functioning in a sample of preschool children in the United States. Sixty-six children's emotion- and cognitive-oriented dimensions of self-regulation were examined with respect to changes in RSA (reactivity and recovery). Results showed that children's recovery RSA, which indicates the ability to return to homeostasis, but not reactivity, was significantly associated with the cognitive-oriented self-regulation.

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.

Early experiences of insensitive caregiving and children's self-regulation: Vagal tone as a differential susceptibility factor

A considerable body of research has linked parenting to the development of children's self-regulation. However, few studies have considered different domains of self-regulation, the effects of early caregiving behaviors, and whether or not parenting influences children equally. Towards this, the present investigation tested how early maternal insensitivity was associated with difficulties in children's effortful control in early childhood and their regulation of negative emotions during the early school years. Further, we tested whether children's resting vagal tone may operate as a susceptibility factor, consistent with differential susceptibility models. The sample included 220 pairs of mothers and their children who were assessed at 18 months, 3.5 years and 5 years of age. Laboratory visits consisted of observational paradigms and survey assessments. Early maternal insensitivity at 18 months of age forecasted difficulties with effortful control at age 3.5. Moreover, effortful control at age 3.5 was associated with greater anger, but not sadness, regulation at age 5. Consistent with differential susceptibility, children's resting vagal tone at 18 months of age moderated the role of early caregiving on children's effortful control. The findings suggest that low resting vagal tone may operate as a differential susceptibility factor in process models testing associations between early caregiving environments and children's self-regulation.

Infants' Biological Sensitivity to the Effects of Maternal Social Support: Evidence Among Mexican American Families

The identification of infants who are most susceptible to both negative and positive social environments is critical for understanding early behavioral development. This study longitudinally assessed the interactive effects of infant vagal tone (respiratory sinus arrhythmia; RSA) and maternal social support on behavioral problems and competence among 322 low-income Mexican American mother-infant dyads (infants: 54.1% female) and explored sex differences. Infant RSA was calculated from resting HR data at 6 weeks of age. Mothers reported on general social support, partner support, and family support at 6 months, and infant behavioral problems and competence at 1 year. Two-way interactions (RSA × support source) were evaluated to predict behavioral problems and competence, adjusting for covariates. Results indicated higher competence among infants with lower RSA whose mothers reported higher general support or higher partner support. Interactive effects on behavior problems of RSA with maternal partner or family support were only found for female infants: Girls with higher RSA showed more behavior problems when mothers reported low support, but fewer problem levels in the context of high support. Our results suggest that infant RSA is an important moderator of the effects of the early social environment on early development.

Sociodemographic risk, parenting, and inhibitory control in early childhood: the role of respiratory sinus arrhythmia

BACKGROUND

Deficits of inhibitory control in early childhood are linked to externalizing behaviors and attention problems. While environmental factors and physiological processes are associated with its etiology, few studies have examined how these factors jointly predict inhibitory control. This study examined whether respiratory sinus arrhythmia (RSA) functioned as a mediator or moderator of both cumulative sociodemographic risk and parenting behaviors on inhibitory control during early childhood.

METHODS

The sample included 206 children and their biological mothers. At 24, 30, and 36 months of child age dyads participated in a series of laboratory visits in which sociodemographic, parenting, and baseline RSA (RSAB) data were collected. Inhibitory control was assessed at 36 months using a gift-wrap delay task.

RESULTS

A series of structural equation models yielded no evidence that RSAB mediated the relations of risk or parenting and inhibitory control. RSAB moderated the effects of risk, such that high-risk children with low RSAB performed more poorly on tasks of inhibitory control, while high-risk children with high RSAB did not.

CONCLUSIONS

These results suggest that higher levels of RSAB may mitigate the influence of environmental risk on the development of inhibitory control early childhood.

Positive Parenting Moderates the Association between Temperament and Self-Regulation in Low-Income Toddlers

Self-regulation develops rapidly during the toddler years and underlies many important developmental outcomes, including social-emotional competence and academic achievement. It is important to understand factors that contribute to early self-regulation skills among children at risk for adjustment difficulties in these domains, such as children growing up in poverty. The current study examined mother-reported child temperament (negative affect, effortful control) and observed maternal parenting (during a mother-child free play) as contributing factors to toddlers' observed self-regulation during delay of gratification tasks at 27 months (snack delay) and 33 months (gift delay). Participants were 198 toddlers (M age = 27 months; 53% boys; 48% non-Hispanic white) and their mothers from low-income families. Mothers' negative parenting characterized by negative affect, hostility, and negative control was associated with poorer self-regulation contemporaneously. Toddlers' lower negative affect and higher effortful control predicted better self-regulation at 33 months, but positive parenting characterized by positive affect and sensitivity moderated these associations at both time points. Specifically, we found a buffering effect of high positive parenting among toddlers with a temperamental risk and a deleterious effect of low positive parenting despite toddlers' temperamental strength. Results highlight the importance of positive parenting for fostering the development of self-regulation among toddlers growing up with poverty-related and child-level risks.

Children's Executive Function Attenuate the Link Between Maternal Intrusiveness and Internalizing Behaviors at School Entry

The goal of this study was to examine the independent and interactive roles of harsh-intrusive maternal behaviors and children's executive function in the development of internalizing behaviors across the first years of school. A diverse sample (58% African American, 42% European American) of 137 children (48% female) was followed from kindergarten (age 5 years) through school entry (ages 6-7 years). At age 5, maternal harsh-intrusive parenting behaviors were rated from a mother-child structured play task, and children completed 3 executive function tasks that measured inhibitory control, working memory, and attention set-shifting. Teachers reported on children's internalizing behaviors at ages 5, 6, and 7. Harsh-intrusive parenting behaviors at age 5 years were positively related to internalizing behaviors in the first years of school, whereas high executive function abilities at age 5 years were related to lower internalizing behaviors in the first years of school. In addition, executive function buffered the association between parenting behaviors and internalizing behaviors such that the link between harsh-intrusive parenting and child internalizing behaviors was evident only among children with low executive function and not among children with high executive function. Interventions that focus on reducing negative parenting behaviors and improving children's executive function may prevent internalizing behaviors from increasing during times of social and academic challenge.