Cardiac reactivity is associated with changes in negative emotion in 24-month-olds

Behavioral and physiological differences during an emotion-evoking task in children at increased likelihood for autism spectrum disorder

Literature examining emotional regulation in infants with autism spectrum disorder (ASD) has focused on parent report. We examined behavioral and physiological responses during an emotion-evoking task designed to elicit emotional states in infants. Infants at an increased likelihood for ASD (IL; have an older sibling with ASD; 96 not classified; 29 classified with ASD at age two) and low likelihood (LL; no family history of ASD; n = 61) completed the task at 6, 12, and 18 months. The main findings were (1) the IL-ASD group displayed higher levels of negative affect during toy removal and negative tasks compared to the IL non-ASD and LL groups, respectively, (2) the IL-ASD group spent more time looking at the baseline task compared to the other two groups, and (3) the IL-ASD group showed a greater increase in heart rate from baseline during the toy removal and negative tasks compared to the LL group. These results suggest that IL children who are classified as ASD at 24 months show differences in affect, gaze, and heart rate during an emotion-evoking task, with potential implications for understanding mechanisms related to emerging ASD.

Somatovisceral influences on emotional development

Frameworks of emotional development have tended to focus on how environmental factors shape children's emotion understanding. However, individual experiences of emotion represent a complex interplay between both external environmental inputs and internal somatovisceral signaling. Here, we discuss the importance of afferent signals and coordination between central and peripheral mechanisms in affective response processing. We propose that incorporating somatovisceral theories of emotions into frameworks of emotional development can inform how children understand emotions in themselves and others. We highlight promising directions for future research on emotional development incorporating this perspective, namely afferent cardiac processing and interoception, immune activation, physiological synchrony, and social touch.

Characterizing change in vagal tone during the first three years of life: A systematic review and empirical examination across two longitudinal samples

Functioning of the parasympathetic nervous system (PNS), most often indexed by respiratory sinus arrhythmia (RSA), influences the volitional, cognitively-mediated forms of self-regulation across development. However, despite its clear relevance to children's self-regulation, and its utility as a transdiagnostic biomarker of emotion dysregulation and psychopathology, the ontogeny of vagal tone under conditions of homeostasis across infancy and early childhood is not well understood. The current research is comprised of two complementary studies. The first aims to address this gap by conducting a systematic review of the literature which has assessed resting RSA in the first three years of life. The second study uses data from two diverse, longitudinal datasets (n = 203 and n = 370) to model change in RSA from infancy to toddlerhood. Results from a systematic review of 62 studies meeting inclusion criteria suggest that measures of resting RSA increase over time and demonstrate moderate stability across infancy, toddlerhood, and preschool ages. Results from a series of models fit to longitudinal data in study two suggest that baseline RSA is characterized by stable increases across infancy and early childhood. Moreover, although there was equivocal evidence for individual variability in trajectories of RSA, the findings suggest that the individual differences in resting RSA may become entrenched in early life based on observed significant variance in growth model intercepts. In all, the current study contributes to our understanding of the developmental trajectories of baseline RSA across infancy and early childhood and should support future research examining links between children's parasympathetic regulation and their adjustment in early life.

Cardiac physiological regulation across early infancy: The roles of infant surgency and parental involvement with mothers and fathers

High baseline respiratory sinus arrhythmia (RSA) and infant temperament are associated with a child's ability to self-regulate, but moderators of this association have not been thoroughly examined in the literature. Parents who are more involved might have more opportunities to interact with and soothe their children. The current study examined whether parental involvement moderated the association between infant temperament and baseline RSA with mothers and fathers across early infancy. Participants included families (n = 91) assessed at 4 and 8 months of age. Infant temperamental surgency and parental involvement were measured via parent-report when infants were 4 months old, and infant baseline RSA was measured at 4 and 8 months of age. Results revealed differences in mother versus father predictors of infant baseline RSA. A significant Infant Surgency X Maternal Play interaction was revealed; infants of mothers who were low involvement increased in their baseline RSA as their surgency increased. A significant main effect of father care was found; infants with highly involved fathers had higher baseline RSA. In conclusion, mothers and fathers may differentially influence their infant's cardiac physiological regulation based on their specific type of involvement.

An examination of the reciprocal and concurrent relations between behavioral and cardiac indicators of acute pain in toddlerhood

The aim of this study was to examine the concurrent and predictive relations between healthy toddlers' pain behavior and cardiac indicators (ie, heart rate [HR] and respiratory sinus arrhythmia [RSA]) during routine vaccinations. Caregiver-infant dyads were part of a longitudinal cohort observed during their 12- and 18-month vaccinations. Behavioral and cardiac data were simultaneously collected for 1-minute preneedle and 3-minutes postneedle. Videotapes were coded for pain behaviors (FLACC; Merkel et al., 1997), and cardiac data were analyzed (HR, RSA) during sequential 30-second epochs. Four separate cross-lagged path models were estimated using data from the 12- (n = 147) and 18-month (n = 122) vaccinations. Across 12- and 18-month vaccinations, predictive within-measure relations were consistent for FLACC, HR, and RSA, reflecting good stability of these pain indicators. Behavioral indicators predicted subsequent HR and RSA within the immediate postneedle period. Both baseline behavior and HR/RSA predicted future pain scores. Concurrent residual relations between behavioral and cardiac indicators were inconsistent across time and indicators. Results suggest that behavioral and cardiac indicators reflect unique aspects of the nociceptive response. As such, multimodal assessment tools should be used and contextualized by child age, cardiac indicator, baseline behavior/physiology, and pain phase.

Physiological responses to a school task: The role of student-teacher relationships and students' emotional appraisal

BACKGROUND

To be successful, students must learn to deal with socially and cognitively demanding tasks. Much remains unknown about the effects of previous classroom experiences and of students' emotional appraisal of a task on their physiological adaptive responses to it.

AIMS

To investigate how children's physiological response to a social and cognitive task would be directly and interactively influenced by the perceived student-teacher relationship and by children's emotional appraisal of what reaction they expect to have while completing the task.

METHODS

One hundred and sixteen second and third graders took part in the study. Children completed a cognitive and social stress task. Before the task, they were interviewed on their emotional appraisal of the task and on student-teacher relationships. Children's cardiac activity was registered at rest and during the task to measure physiological activation (heart rate) and self-regulation (heart rate variability).

RESULTS

Heart rate variability during the task was positively correlated with the appraised emotional valence of the task and of being observed while doing it. Regression analyses showed that children's physiological self-regulation during the task was affected by the interaction between student-teacher relationships and appraised emotional valence of being observed. Only among children who had experienced negative student-teacher relationships, an active physiological self-regulation was observed in response to the task when they expected it to be positive compared to when they perceived it as negative.

CONCLUSIONS

Children's emotional appraisal of tasks and the quality of student-teacher relationships are important to promote a functional physiological response of self-regulation that underlies academic functioning and well-being at school.

Maternal dynamic respiratory sinus arrhythmia during toddlers' interactions with novelty

Maternal psychophysiological responses to toddlers' distress to novelty may have important implications for parenting during early childhood that are relevant to children's eventual development of social withdrawal and anxiety. Likely, these responses depend on intrapersonal, interpersonal, and contextual factors. The current study investigated the time course of respiratory sinus arrhythmia (RSA) across two laboratory novelty episodes, one low threat and one moderate threat, in 120 mothers of 2-year-old toddlers. Growth models tested context differences in and correlates of dynamic patterns of RSA. Dynamic patterns differed between tasks and according to mothers' perceptions of and distress about toddler shyness. Thus, changes in mothers' RSA across toddlers' interactions with novelty seem to depend on the context as well as how mothers perceive and respond to their toddlers' shyness.

Physiological measurement of emotion from infancy to preschool: A systematic review and meta-analysis

INTRODUCTION

Emotion regulation, the ability to regulate emotional responses to environmental stimuli, develops in the first years of life and plays an important role in the development of personality, social competence, and behavior. Substantial literature suggests a relationship between emotion regulation and cardiac physiology; specifically, heart rate changes in response to positive or negative emotion-eliciting stimuli.

METHOD

This systematic review and meta-analysis provide an in-depth examination of research that has measured physiological responding during emotional-evoking tasks in children from birth to 4 years of age.

RESULTS

The review had three main findings. First, meta-regressions resulted in an age-related decrease in baseline and task-related heart rate (HR) and increases in baseline and task-related respiratory sinus arrhythmia (RSA). Second, meta-analyses suggest task-related increases in HR and decreases in RSA and heart rate variability (HRV), regardless of emotional valence of the task. Third, associations between physiological responding and observed behavioral regulation are not consistently present in children aged 4 and younger. The review also provides a summary of the various methodology used to measure physiological reactions to emotional-evoking tasks, including number of sensors used and placement, various baseline and emotional-evoking tasks used, methods for extracting RSA, as well as percentage of loss and reasons for loss for each study.

CONCLUSION

Characterizing the physiological reactivity of typically developing children is important to understanding the role emotional regulation plays in typical and atypical development.

Affective Neural Mechanisms of a Parenting-Focused Mindfulness Intervention

OBJECTIVES

Behavioral evidence suggests that parenting-focused mindfulness interventions can improve parenting practices and enhance family wellbeing, potentially operating through altered emotional processing in parents. However, the mechanisms through which parent mindfulness interventions achieve their positive benefits have not yet been empirically tested, knowledge which is key to refine and maximize intervention effects. Thus, as part of a randomized controlled trial, the present study examined the affective mechanisms of an 8-week parenting-focused mindfulness intervention, the Parenting Mindfully (PM) intervention, versus a minimal-intervention parent education control.

METHODS

Twenty highly stressed mothers of adolescents completed pre- and post-intervention behavioral and fMRI sessions, in which mothers completed a parent-adolescent conflict interaction, fMRI emotion task, and fMRI resting state scan. Mothers reported on their mindful parenting, and maternal emotional reactivity to the parent-adolescent conflict task was assessed via observed emotion expression, self-reported negative emotion, and salivary cortisol reactivity.

RESULTS

Results indicated that the PM intervention increased brain responsivity in left posterior insula in response to negative affective stimuli, and altered resting state functional connectivity in regions involved in self-reference, behavioral regulation, and social-emotional processing. Changes in mothers' brain function and connectivity were associated with increased mindful parenting and decreased emotional reactivity to the parent-adolescent conflict task.

CONCLUSIONS

Findings suggest that mindfulness-based changes in maternal emotional awareness at the neurobiological level are associated with decreased emotional reactivity in parenting interactions, illuminating potential neurobiological targets for future parent-focused intervention.

Investigating convergence of cardiac and behavioral indicators of distress during routine vaccinations over the second year of life

There is considerable variability regarding the convergence between behavioral and biological aspects of distress responses in toddlerhood, and little research has investigated the convergence of these measures in high distress. The aim of the current study was to describe patterns of distress responses to vaccinations as indexed by both pain-related behavioral distress and heart rate (HR) at 12 and 18 months. Caregiver-toddler dyads were part of an ongoing longitudinal cohort observed during 12- (N = 158) and 18-month (N = 122) well-baby vaccinations. Parallel-process growth mixture models discerned two distinct groups at 12 months and three distinct groups at 18 months. All groups had comparable pain-related behavioral distress and HR responses post-vaccination, with most participants displaying high arousal and regulation to baseline levels following the vaccination. However, at 18 months, an important minority had a blunted response or did not regulate to a low level of distress by 3 min post-needle. Post hoc analyses revealed that higher baseline pain-related behavioral distress predicted membership in the majority groups at 12 and 18 months. These results highlight the developmental differences and variability in behavioral and cardiac indicators of distress regulation across the second year of life.

Getting to the heart of childhood empathy: Relations with shyness and respiratory sinus arrhythmia

Although prior studies have found that shyness and empathy are inversely related and that well-regulated children tend to express empathic behaviors more often, little work has assessed combinations of these factors in predicting affective and cognitive empathy in early childhood. The authors examined relations among shyness, resting respiratory sinus arrhythmia (RSA), and observed affective and cognitive empathy in a sample of 130 typically developing children (M_age  = 63.5 months, SD = 12.2; 62 males). Shyness was assessed by observing children's behaviors during a self-presentation task, and this observed measure was then combined with a maternal report of children's temperamental shyness. Children's shyness predicted lower levels of both affective and cognitive responses to an experimenter feigning an injury. Resting RSA moderated the relation between children's shyness and observed empathy such that relatively higher shyness combined with lower RSA levels conferred the lowest levels of cognitive empathy. Children who were relatively low in shyness exhibited similar levels of cognitive empathy across different levels of RSA. However, this moderation was not found when predicting children's affective empathy. Our results suggest that not all shy children are alike in terms of their empathic behaviors: shy children who are physiologically dysregulated appear to have difficulties exploring and/or processing others' pain.

Developmental patterns of respiratory sinus arrhythmia from toddlerhood to adolescence

Parasympathetic nervous system functioning as indexed by respiratory sinus arrhythmia (RSA) is widely used as a measure of physiological regulation. We examined developmental patterns of children's resting RSA and RSA reactivity from 2 to 15 years of age, a period of time that is marked by considerable advances in children's regulatory abilities. Physiological data were collected from a community sample of 270 children (116 males) during a resting period and during a frustration laboratory task when the children were 2, 4, 5, 7, 10, and 15 years old. We examined both stability and continuity in resting RSA and RSA reactivity across time. We found stability in resting RSA but not RSA reactivity from toddlerhood to adolescence. Separate multilevel models were used to examine changes in resting RSA and RSA reactivity from Age 2 to Age 15. The rate of change in resting RSA slowed from Age 2 to Age 15 with a plateau around Age 10. A splined growth model indicated that the rate of RSA reactivity increased from Age 2 to Age 7 and a modest slowing and leveling off from Age 7 to Age 15. Understanding the developmental characteristics of RSA across childhood and adolescence is important to understanding the larger constructs of self- and emotion regulation. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Autonomic nervous system functioning in early childhood: Responses to cognitive and negatively valenced emotional challenges

Although autonomic nervous system (ANS) functioning is "context-dependent," few studies examined children's normative sympathetic and parasympathetic autonomic responses to distinct challenges in early childhood years. Examining children's ANS responsivity to distinct challenges is important for understanding normative autonomic responses toward everyday life stressors and identifying paradigms that effectively elicit a "stress response." We examined children's (N = 278) sympathetic (preejection period [PEP]) and parasympathetic (respiratory sinus arrhythmia [RSA]) responses to cognitive (i.e., problem-solving and cognitive control) and negatively valenced emotional (i.e., blocked goal and unfairness) challenges in preschool, kindergarten, and grade 1. Children, on average, demonstrated parasympathetic inhibition (RSA withdrawal) in response to all challenges but the magnitude of these responses depended on the task. Children showed sympathetic activation (PEP shortening) toward the problem-solving task at each assessment and there was no sample-level change in the magnitude of this response over time. Children showed greater sympathetic responsivity toward the cognitive control task over time, with evidence for a sympathetic activation response only in grade 1. Children experienced sympathetic inhibition (PEP lengthening) toward the unfairness tasks but did not experience significant sympathetic responsivity toward the blocked goal tasks. Parasympathetic responsivity to most challenges were modestly stable but there was no stability in sympathetic responsivity across time.

Temperamental vulnerability to emotion dysregulation and risk for mental and physical health challenges

Emotion dysregulation characterizes many forms of psychopathology. Patterns of dysregulation occur as a function of a developmental process in which normative and adaptive emotion regulation skills fail to become part of the child's behavioral repertoire due to biological, psychological, and contextual processes and experiences. Here we highlight the processes involved in the dysregulation of temperamental anger and frustration that become core features of externalizing problems and place children at risk for more serious forms of psychopathology. We imbed these processes in a larger self-regulatory framework, and we discuss how they influence mental as well as physical health, using data from our 20-year longitudinal study following a large cohort of children into young adulthood. Recommendations are made for future research involving the integration of biological systems with mental and physical health outcomes.

Age-Adapted Stress Task in Preschoolers Does not Lead to Uniform Stress Responses

Acute stress response measures serve as an indicator of physiological functioning, but have previously led to contradictory results in young children due to age-related cortisol hypo-responsivity and methodological inconsistencies in assessment. The aim of this study was to investigate stress responses during a validated age-adapted socio-evaluative stress task in children aged 2-6 years in a child care environment and to detect socio-demographic, task- and child-related characteristics of stress responses. Stress responses were assessed in 323 children for salivary cortisol and salivary alpha amylase (sAA), and in 328 children for changes in heart rate variability (HRV). These data were then associated with socio-demographic (e.g. SES), task-related (e.g. task length) and child-related characteristics (e.g. self-regulation) of stress responses using multilevel models. Analyses revealed elevated sympathetic reactivity (sAA: Coeff=0.053, p=0.004) and reduced HRV (Coeff=-0.465, p<0.001), but no hypothalamic-pituitary-adrenal (HPA) response (Coeff=0.017, p=0.08) during the stress task. Child's age (Coeff=-5.82, p<0.001) and movement during the task (Coeff=-0.17, p=0.015) were associated with acute cortisol release, while diurnal sAA was associated with acute sAA release (Coeff=0.24, p<0.001). Age (Coeff=-0.15, p=0.006) and duration of the task (Coeff=0.13, p=0.015) were further associated with change of HRV under acute stress condition. Children showed inconsistent stress responses which contradicts the assumption of a parallel activation of both stress systems in a valid stress task for young children and might be explained by a pre-arousal to the task of young children in a child care setting. Further results confirm that child- and task-related conditions need to be considered when assessing stress responses in these young children.

Dysregulated Fear, Social Inhibition, and Respiratory Sinus Arrhythmia: A Replication and Extension

Behavioral inhibition indicates increased risk for development of social anxiety. Recent work has identified a pattern of dysregulated fear (DF), characterized by high fear in low-threat situations, that provides a more precise marker of developmental risk through early childhood. This study tested a new longitudinal sample of children (n = 124) from ages 24 to 48 months. Replicating prior findings, at 24 months, we identified a pattern of fearful behavior across contexts marked by higher fear to putatively low-threat situations. DF was associated with higher parental report of social inhibition at 24, 36, and 48 months. Extending prior findings, we observed differences in cardiac physiology during fear-eliciting situations, suggesting that the neurobiological underpinnings of DF relate to difficulty with regulation.

Parent emotion regulation socializes children's adaptive physiological regulation

Parenting practices play a major role in socializing children's developing regulatory abilities, but less is known about how parents' regulatory abilities relate to children's healthy functioning. This study examined whether parents' physiological and emotion regulation abilities corresponded to children's physiological and emotional responding to a structured laboratory-based disappointment task. Ninety-seven 3- to 7-year-olds (56 girls; M = 5.79 years) and one parent participated in a multi-method assessment of parents' and children's regulatory functioning. Direct (coaching children to use reappraisal) and indirect (resting physiology, dispositional use of reappraisal) aspects of parents' regulatory abilities were assessed. As expected, an adaptive pattern of parent regulatory abilities composed of higher resting respiratory sinus arrhythmia, use of reappraisal, and coaching reappraisal was associated with children's physiological reactivity after a disappointment indicative of more effective physiological calming in a recovery context (increased parasympathetic activation). In contrast, parents' regulatory abilities did not relate to changes in children's expressions of emotional distress.

Children's Autonomic Nervous System Reactivity Moderates the Relations between Family Adversity and Sleep Problems in Latino 5-Year Olds in the CHAMACOS Study

Sleep problems are common for young children especially if they live in adverse home environments. Some studies investigate if young children may also be at a higher risk of sleep problems if they have a specific biological sensitivity to adversity. This paper addresses the research question, does the relations between children’s exposure to family adversities and their sleep problems differ depending on their autonomic nervous system’s sensitivity to challenges? As part of a larger cohort study of Latino, low-income families, we assessed the cross-sectional relations among family demographics (education, marital status), adversities [routines, major life events (MLE)], and biological sensitivity as measured by autonomic nervous system (ANS) reactivity associated with parent-rated sleep problems when the children were 5 years old. Mothers were interviewed in English or Spanish and completed demographic, family, and child measures. The children completed a 15-min standardized protocol while continuous cardiac measures of the ANS [respiratory sinus arrhythmia (RSA), preejection period (PEP)] were collected during resting and four challenge conditions. Reactivity was defined as the mean of the responses to the four challenge conditions minus the first resting condition. Four ANS profiles, co-activation, co-inhibition, reciprocal low RSA and PEP reactivity, and reciprocal high RSA and PEP reactivity, were created by dichotomizing the reactivity scores as high or low reactivity. Logistic regression models showed there were significant main effects for children living in families with fewer daily routines having more sleep problems than for children living in families with daily routines. There were significant interactions for children with low PEP reactivity and for children with the reciprocal, low reactivity profiles who experienced major family life events in predicting children’s sleep problems. Children who had a reciprocal, low reactivity ANS profile had more sleep problems if they also experienced MLE than children who experienced fewer MLE. These findings suggest that children who experience family adversities have different risks for developing sleep problems depending on their biological sensitivity. Interventions are needed for young Latino children that support family routines and reduce the impact of family adversities to help them develop healthy sleep practices.

Psychophysiological Assessment of the Effectiveness of Emotion Regulation Strategies in Childhood

Effective regulation of emotion is one of the most important skills that develops in childhood. Research interest in this area is expanding, but empirical work has been limited by predominantly correlational investigations of children's skills. Relatedly, a key conceptual challenge for emotion scientists is to distinguish between emotion responding and emotion regulatory processes. This paper presents a novel method to address these conceptual and methodological issues in child samples. An experimental paradigm that assesses the effectiveness with which children regulate emotion is described. Children are randomly assigned to use specific emotion regulation strategies, negative emotions are elicited with film clips, and changes in subsequent psychophysiology index the extent to which emotion regulation is effective. Children are instructed to simply watch the emotion-eliciting film (control), distract themselves from negative emotions (cognitive distraction), or reframe the situation in a way that downplays the importance of the emotional event (cognitive reappraisal). Cardiac physiology, continuously acquired before and during the emotional task, serves as an objective measure of children's unfolding emotional responding while viewing evocative films. Key comparisons in patterns of obtained physiological reactivity are between the control and emotion regulation strategy conditions. Representative results from this approach are described, and discussion focuses on the contribution of this methodological approach to developmental science.

Early caregiving stress exposure moderates the relation between respiratory sinus arrhythmia reactivity at 1 month and biobehavioral outcomes at age 3

There is a growing scientific interest in the psychophysiological functioning of children living in low-socioeconomic status (SES) contexts, though this research is complicated by knowledge that physiology-behavior relations often operate differently in these environments among adults. Importantly, such research is made more difficult because SES may be a proxy for a wide range of risk factors including poor caregiving and exposure to parental substance use. We used factor analysis to organize risk-exposure data collected from 827 children-many of whom were raised in low-SES contexts and exposed to substances prenatally-into dissociable components including economic stress, caregiving stress (e.g., stress the caregiver may experience, including parental psychopathology), and postnatal substance exposure. These factors, along with respiratory sinus arrhythmia (RSA) reactivity at age 1 month, were used to predict behavior dysregulation and resting RSA at age 3 years. A significant RSA Reactivity × Caregiving Stress interaction indicated that infants who exhibited high RSA reactivity at 1 month experienced the greatest behavior dysregulation at 3 years, but only when they were exposed to high levels of caregiving stress. Among African Americans, the highest resting RSA at 3 years was found in infants with less RSA reactivity, but only if they also experienced less caregiving stress. Our work is consistent with biological sensitivity to context, adaptive calibration, and allostatic load models, and highlights the importance of studying Physiology × Environment interactions in low-SES contexts for predicting behavior and resting RSA.

Vagal tone during infant contingency learning and its disruption

This study used contingency learning to examine changes in infants' vagal tone during learning and its disruption. The heart rate of 160 five-month-old infants was recorded continuously during the first of two training sessions as they experienced an audiovisual event contingent on their pulling. Maternal reports of infant temperament were also collected. Baseline vagal tone, a measure of parasympathetic regulation of the heart, was related to vagal levels during the infants' contingency learning session, but not to their learner status. Vagal tone levels did not vary significantly over session minutes. Instead, vagal tone levels were a function of both individual differences in learner status and infant soothability. Vagal levels of infants who learned in the initial session were similar regardless of their soothability; however, vagal levels of infants who learned in a subsequent session differed as a function of soothability. Additionally, vagal levels during contingency disruption were significantly higher among infants in this group who were more soothable as opposed to those who were less soothable. The results suggest that contingency learning and disruption is associated with stable vagal tone in the majority of infants, but that individual differences in attention processes and state associated with vagal tone may be most readily observed during the disruption phase.

Improving the Prediction of Risk for Anxiety Development in Temperamentally Fearful Children

Pediatric anxiety disorders are among the most common disorders in children and adolescence resulting in both short-term and long-term negative consequences across a variety of domains including social and academic. Early fearful temperament has emerged as a strong predictor of anxiety development in childhood; however, not all fearful children become anxious. The current article summarizes theory and evidence for heterogeneity in the identification of temperamentally fearful children and trajectories of risk for anxiety. The findings presented in this article reveal that identification of subgroups of fearful temperament improves prediction of who is at risk for developing anxiety problems.

Adolescent Substance Use & Psychopathology: Interactive Effects of Cortisol Reactivity and Emotion Regulation

How are emotional processes associated with the increased rates of substance use and psychological disorders commonly observed during adolescence? An index of emotion-related physiological arousal-cortisol reactivity-and subjective emotion regulation have both been independently linked to substance use and psychological difficulties among youth. The current study (N = 134 adolescents) sought to elucidate the interactive effects of cortisol reactivity following a stressful parent-child interaction task and self-reported emotion regulation ability on adolescents' substance use and externalizing and internalizing behavior problems. Results revealed that adolescents with low levels of cortisol reactivity and high emotion regulation difficulties were more likely to use substances, and also had the highest parent-reported symptoms of oppositional defiant disorder. With respect to internalizing symptoms, high emotion-related physiological reactivity coupled with high emotion regulation difficulties were associated with higher self-reported major depression symptoms among youth. Findings reveal that different profiles of HPA axis arousal and emotion regulation are associated with substance use and symptoms of psychopathology among adolescents.

A person-centered approach to adolescent emotion regulation: Associations with psychopathology and parenting

Adolescence is a unique period of heightened emotional arousal and still-developing regulatory abilities. Adolescent emotion regulation patterns may be critically involved in adolescents' psychosocial development, but patterns of emotion regulation in youths are not well understood. The current study used latent profile analysis (LPA) to elucidate patterns of emotion expression, experience, and emotion-related physiological arousal in adolescents. A sample of 198 adolescents and their primary caregivers participated in an emotionally arousing parent-adolescent conflict interaction. Adolescents' observed emotion expressions, emotion experiences, and heart rate (HR) and caregiver parenting behaviors were assessed during and/or after the interaction. Parents reported on adolescents' internalizing and externalizing symptoms, and youths reported on depressive symptoms. The LPA revealed four emotion regulation profiles: a moderate HR and high expression profile, a suppression profile (with low negative emotion expression and high emotion experience), a low reactive profile, and a high reactive profile. The moderate HR and high expression profile was associated with lower conduct disorder symptoms, the suppression profile was related to lower anxiety symptoms, and the high reactive profile was associated with higher adolescent depressive symptoms. The high reactive profile and moderate HR and high expression profile were associated with more negative/critical parenting behaviors. Findings suggest that profiles of adolescent emotion regulation can be empirically identified and may be significant risk factors for psychopathology.

Longitudinal associations between temperament and socioemotional outcomes in young children: the moderating role of RSA and gender

Temperament is an important predictor of socioemotional adjustment, such as externalizing and internalizing symptoms. However, there is not a one-to-one correspondence between temperamental predispositions and these outcomes, implying that other factors also contribute to the development of internalizing and externalizing problems. Self-regulation is believed to interact with temperament, and has been studied as a predictor for later socioemotional outcomes. Respiratory sinus arrhythmia (RSA) is a psychophysiological measure of self-regulation that has been studied as a moderator of risk. The primary aim of the present study was to test if RSA baseline and RSA reactivity would moderate the link between temperament and socioemotional outcomes. Mothers reported the temperament of their infants (20 months; N = 154), RSA was collected at 24- and 42-months, and mothers reported externalizing and internalizing behaviors at kindergarten entry. RSA baseline and RSA reactivity moderated the relation between exuberant temperament and externalizing behaviors. However, these results were only significant for girls, such that high RSA baseline and greater RSA suppression predicted more externalizing behaviors when exuberance was high. Fearful temperament predicted later internalizing behaviors, but no moderation was present. These results are discussed in light of recent evidence regarding gender differences in the role of RSA as a protective factor for risk.

The contributions of early adverse experiences and trajectories of respiratory sinus arrhythmia on the development of neurobehavioral disinhibition among children with prenatal substance exposure

Neurobehavioral disinhibition (ND) is a complex condition reflecting a wide range of problems involving difficulties with emotion regulation and behavior control. Respiratory sinus arrhythmia (RSA) is a physiological correlate of emotion regulation that has been studied in a variety of at-risk populations; however, there are no studies of RSA in children with ND. Data were drawn from a prospective longitudinal study of prenatal substance exposure that included 1,073 participants. Baseline RSA and RSA reactivity to an attention-demanding task were assessed at 3, 4, 5, and 6 years. ND was assessed at ages 8/9, 11, and 13/14 years via behavioral dysregulation and executive dysfunction composite measures. Greater exposure to early adversity was related to less RSA reactivity at 3 years, increases in RSA reactivity from ages 3 to 6 years, and increased behavioral dysregulation from ages 8/9 to 13/14. RSA reactivity was examined as a moderator of the association between early adversity and changes in ND. A significant Early Adversity × RSA Reactivity quadratic interaction revealed that children with decelerations in RSA reactivity exhibited increases in behavioral dysregulation, regardless of their exposure to early adversity. However, greater exposure to early adversity was related to greater increases in behavioral dysregulation, but only if children exhibited accelerations in RSA reactivity from ages 3 to 6 years. The results contribute to our understanding of how interactions across multiple levels of analysis contribute to the development of ND.

Physiological correlates of neurobehavioral disinhibition that relate to drug use and risky sexual behavior in adolescents with prenatal substance exposure

Physiological correlates of behavioral and emotional problems, substance use onset and initiation of risky sexual behavior have not been studied in adolescents with prenatal drug exposure. We studied the concordance between baseline respiratory sinus arrhythmia (RSA) at age 3 and baseline cortisol levels at age 11. We hypothesized that children who showed concordance between RSA and cortisol would have lower neurobehavioral disinhibition scores which would in turn predict age of substance use onset and first sexual intercourse. The sample included 860 children aged 16 years participating in the Maternal Lifestyle Study, a multisite longitudinal study of children with prenatal exposure to cocaine and other substances. Structural equation modeling was used to test pathways between prenatal substance exposure, early adversity, baseline RSA, baseline cortisol, neurobehavioral disinhibition, drug use, and sexual behavior outcomes. Concordance was studied by examining separate male and female models in which there were statistically significant interactions between baseline RSA and cortisol. Prenatal substance exposure was operationalized as the number of substances to which the child was exposed. An adversity score was computed based on caregiver postnatal substance use, depression and psychological distress, number of caregiver changes, socioeconomic and poverty status, quality of the home environment, and child history of protective service involvement, abuse and neglect. RSA and cortisol were measured during a baseline period prior to the beginning of a task. Neurobehavioral disinhibition, based on composite scores of behavioral dysregulation and executive dysfunction, substance use and sexual behavior were derived from questionnaires and cognitive tests administered to the child. Findings were sex specific. In females, those with discordance between RSA and cortisol (high RSA and low cortisol or low RSA and high cortisol) had the most executive dysfunction which, in turn, predicted earlier initiation of alcohol by age 16. Among boys, there also existed a significant baseline RSA by baseline cortisol interaction. Boys with low baseline RSA and high baseline cortisol had the highest levels of behavioral dysregulation. This increase in behavioral dysregulation was in turn related to initiation of alcohol use by age 16 and lower age of first sexual intercourse. We found sex-specific pathways to the initiation of alcohol use and risky sexual behavior through the combined activity of parasympathetic and neuroendocrine functioning. The study of multiple physiological systems may suggest new pathways to the study of age of onset of substance use and engagement in risky sexual behavior in adolescents.

How well socially wary preschoolers fare over time depends on their parasympathetic regulation and socialization

Parasympathetic regulation and maternal overprotective parenting were examined in 101 children as moderators of links between preschool (M = 3.53 years) social wariness and childhood (M = 9.07 years) internalizing and anxiety problems, social skills, and scholastic performance. Across these three domains of functioning, more socially wary children were likely to manifest worse adjustment when they had low respiratory sinus arrhythmia (RSA) or highly overprotective mothers. Conversely, maternal overprotection appeared to confer benefits for preschoolers with low wariness and low RSA. These findings point to the importance of both internal self-regulatory capacities and external support for autonomy and competence to understand and assist socially wary children and their families.

The role of prenatal substance exposure and early adversity on parasympathetic functioning from 3 to 6 years of age

We employed latent growth curve analysis to examine trajectories of respiratory sinus arrhythmia (RSA) from 3 to 6 years among children with varying levels of prenatal substance exposure and early adversity. Data were drawn from a prospective longitudinal study of prenatal substance exposure that included 1,121 participants. Baseline RSA and RSA reactivity to an attention-demanding task were assessed at 3, 4, 5, and 6 years. Overall, there were significant individual differences in the trajectories of RSA reactivity, but not baseline RSA, across development. Greater levels of prenatal substance exposure, and less exposure to early adversity, were associated with increased RSA reactivity at 3 years, but by 6 years, both were associated with greater RSA reactivity. Prenatal substance exposure had an indirect influence through early adversity on growth in RSA reactivity. Results are in support of and contribute to the framework of allostatic load.

The development of stranger fear in infancy and toddlerhood: normative development, individual differences, antecedents, and outcomes

Despite implications that stranger fear is an important aspect of developing behavioral inhibition, a known risk factor for anxiety, normative and atypical developmental trajectories of stranger fear across infancy and toddlerhood remain understudied. We used a large, longitudinal data set (N = 1285) including multi-trait, multi-method assessments of temperament to examine the normative course of development for stranger fear and to explore the possibility that individual differences exist in trajectories of stranger fear development between 6 and 36 months of age. A latent class growth analysis suggested four different trajectories of stranger fear during this period. Stable, high levels of stranger fear over time were associated with poorer RSA suppression at 6 months of age. Rates of concordance in trajectory-based class membership for identical (monozygotic) and fraternal (dizygotic) twins, along with associations between atypical stranger fear development and greater anxiety-related maternal characteristics, suggested that individual differences in developmental trajectories of stranger fear may be heritable. Importantly, trajectories of stranger fear during infancy and toddlerhood were linked to individual differences in behavioral inhibition, with chronically high levels of stranger fear and sharp increases in stranger fear over time related to greater levels of inhibition than other developmental trajectories.

Development of fear and guilt in young children: stability over time and relations with psychopathology

Extremes in fearful temperament have long been associated with later psychopathology and risk pathways. Whereas fearful children are inhibited and anxious and avoid novel events, fearless individuals are disinhibited and more likely to engage in aggressive behavior. However, very few studies have examined fear in infants from a multimethod and prospective longitudinal perspective. This study had the following objectives: to examine behavioral, maternal reported, and physiological indices of fearful temperament in infancy, together with their relations and stability over time; and to establish whether early indices of fear predict fear later in toddlerhood. We also examined the association between behavioral and physiological measures of fear and guilt and whether fear in infancy predicts guilt in toddlers. Finally, we investigated infant risk factors for later psychopathology. We recorded skin conductance level (SCL) and heart rate (HR) and observed children's responses during a Laboratory Temperament Assessment Battery fear paradigm across the first 3 years of life and during a guilt induction procedure at age 3 (N = 70). The results indicate that different measures of infant fear were associated across time. Observed fearlessness in infancy predicted observed fearlessness and low levels of SCL arousal to fear and guilt in toddlers. Low levels of HR and SCL to fear in infancy predicted low levels of physiological arousal to the same situation and to guilt 2 years later. Fear and guilt were significantly associated across measures. Finally, toddlers with clinically significant internalizing problems at age 3 were already notably more fearful in Year 1 as reflected by their significantly higher HR levels. The results indicated that assessments of children in infancy are predictive of how these children react 2 years later and therefore lend support to the idea that the emotional thermostat is set in the first 3 years of life. They also showed, for the first time, that infant fear is a predictor of guilt, which is an emotion that develops later. The implications of these findings for our understanding of developmental psychopathology are discussed.

Stress reactivity and corticolimbic response to emotional faces in adolescents

OBJECTIVE

Adolescence is a critical period in the development of lifelong patterns of responding to stress. Understanding underpinnings of variations in stress reactivity in adolescents is important, as adolescents with altered stress reactivity are vulnerable to negative risk-taking behaviors including substance use, and have increased lifelong risk for psychopathology. Although both endocrinological and corticolimbic neural system mechanisms are implicated in the development of stress reactivity patterns, the roles of these systems and interactions between the systems in reactivity to social stimuli in adolescents are not clear. We investigated the relationship between cortisol response to a laboratory-based social stressor and regional brain responses to emotional face stimuli in adolescents.

METHOD

Changes in cortisol levels following the Trier Social Stress Test-Child version (TSST-C) were measured in 23 disadvantaged and chronically stressed adolescents who also participated in functional magnetic resonance imaging during processing of emotional faces and structural magnetic resonance imaging. The relationships between changes in cortisol following the TSST-C with regional brain activation during face processing, as well as with regional brain morphology, were assessed.

RESULTS

Cortisol change on the TSST-C showed a significant inverse relationship with left hippocampus response to fearful faces (p < .05, corrected); significant associations with volume were not observed.

CONCLUSIONS

Increased cortisol response to the Trier social stressor was associated with diminished response of the left hippocampus to faces depicting fear. This suggests that HPA-corticolimbic system mechanisms may underlie vulnerability to maladaptive responses to stress in adolescents that may contribute to development of stress-related disorders.

Differential susceptibility and the early development of aggression: interactive effects of respiratory sinus arrhythmia and environmental quality

The purpose of the current study was to predict the development of aggressive behavior from young children's respiratory sinus arrhythmia (RSA) and environmental quality. In a longitudinal sample of 213 children, baseline RSA, RSA suppression in response to a film of crying babies, and a composite measure of environmental quality (incorporating socioeconomic status and marital adjustment) were measured, and parent-reported aggression was assessed from 18 to 54 months of age. Predictions based on biological sensitivity-to-context/differential susceptibility and diathesis-stress models, as well as potential moderation by child sex, were examined. The interaction of baseline RSA with environmental quality predicted the development (slope) and 54-month intercept of mothers' reports of aggression. For girls only, the interaction between baseline RSA and environmental quality predicted the 18-month intercept of fathers' reports. In general, significant negative relations between RSA and aggression were found primarily at high levels of environmental quality. In addition, we found a significant Sex × RSA interaction predicting the slope and 54-month intercept of fathers' reports of aggression, such that RSA was negatively related to aggression for boys but not for girls. Contrary to predictions, no significant main effects or interactions were found for RSA suppression. The results provide mixed but not full support for differential susceptibility theory and provide little support for the diathesis-stress model.

Expression of anger in depressed adolescents: the role of the family environment

The expression of anger is considered to be abnormal in depression, yet its role is only poorly understood. In the present study we sought to clarify this role by examining the moderating influence of the family environment on overall levels of anger expression and anger reactivity in depressed and non-depressed adolescents during conflictual interactions with their parents. One hundred and forty one depressed and non-depressed adolescent participants engaged in a problem-solving task with their parents during which their behavioral expression of anger and heart rate were recorded. The results demonstrate that general levels of parental anger in the family environment (as indicated by the overall level of expressed anger by the parents during the interactions) strongly moderates how depressed differ from non-depressed adolescents in terms of their anger, heart rate and reactivity. Overall, the findings suggest that in depressed adolescents anger is much less adaptively attuned to the environment, consistent with models that predict dysfunction in the regulation of anger that prevents depressed individuals responding adaptively to their social environment.

The interactive effect of marital conflict and stress reactivity on externalizing and internalizing symptoms: the role of laboratory stressors

Growing evidence supports the biological sensitivity to context theory, which posits that physiologically reactive children, as indexed by autonomic nervous system (ANS) reactivity to laboratory stressors, are more susceptible to both negative and positive environmental influences than their low reactive peers. High biological sensitivity is a risk factor for behavioral and health problems in the context of high adversity, whereas in contexts of low adversity it has been found to promote positive adaptation. However, several studies have shown the opposite effect, finding that children who exhibited high ANS reactivity in response to interpersonal stressors were buffered from the deleterious effects of marital conflict, whereas children who showed low ANS reactivity were more vulnerable to high levels of marital conflict. Using an ethnically diverse sample of 260 kindergartners (130 girls, 130 boys), the current study investigated whether the interaction effect of marital conflict and the two branches of ANS reactivity on children's externalizing and internalizing symptoms differs with the nature of the laboratory challenge task used to measure children's stress response. As hypothesized, results indicate that the interaction between ANS reactivity and marital conflict significantly predicted children's behavior problems, but the direction of the effect varied with the nature of the challenge task (i.e., interpersonal or cognitive). This study illustrates the importance of considering the effect of laboratory stimuli when assessing whether children's ANS reactivity moderates the effects of adversity exposure on adaptation.

Dynamic measures of RSA predict distress and regulation in toddlers

In this study, we examined a new method for quantifying individual variability using dynamic measures of respiratory sinus arrhythmia (RSA). This method incorporated temporal variation into the measurement of RSA and provided information beyond that offered by more traditional quantifications such as difference scores. Dynamic and static measures of change in RSA were tested in relation to displays of emotion and affective behaviors during a fear-eliciting episode in a sample of 88 typically developing and high-fear toddlers during a laboratory visit at age 24 months. Dynamic measures of RSA contributed information that was unique from traditionally employed, static change scores in predicting high-fear toddlers' displays of shyness during a fear-eliciting episode. In contrast, RSA change scores offered information related to boldness in nonhigh-fear children. In addition, several associations included estimates of nonlinear change in RSA. Implications for the study of individual differences in RSA and relations with emotion and emotion regulation are discussed.

Developmental differences in infant salivary alpha-amylase and cortisol responses to stress

This study examined developmental differences in infants' salivary alpha-amylase (sAA) and cortisol levels and responses to the well-baby exam/inoculation stress protocol at 2, 6, 12, and 24 months of age. Mother-infant pairs (n=85; 45 girls) were assessed during well-baby visits and saliva was sampled before the well-baby exam/inoculation procedure (pre-test) and at 5, 10, and 20 min post-inoculation stress. Older infants (24 months) had higher levels of sAA than younger infants (2, 6 and 12 months). Stress-related sAA increases were evident at 6 and 12 months, but not at 2 or 24 months of age. Stress-related cortisol increases were present at 2 and 6 months, but not at older ages. Mothers had higher sAA levels than their infants, but did not show sAA or cortisol increases to their infants' inoculation. Pre-test, maternal and infant sAA levels were positively correlated (rs .47 to .65) at 6, 12, and 24 months of age, but not at 2 months. These findings suggest that the association between the sympathetic branch of the autonomic nervous system and the secretion of sAA develops between 2 and 6 months of age, when levels of sAA are responsive to exposure to a painful stressor.

Salivary alpha-amylase and cortisol in toddlers: differential relations to affective behavior

This study applies a minimally invasive and multi-system measurement approach (using salivary analytes) to examine associations between the psychobiology of the stress response and affective behavior in toddlers. Eighty-seven 2-year-olds (48 females) participated in laboratory tasks designed to elicit emotions and behavior ranging from pleasure/approach to fear/withdrawal. Saliva samples were collected pretask and immediately posttask, and assayed for markers of sympathetic nervous system (alpha-amylase or sAA) and hypothalamic-pituitary-adrenal axis (cortisol) activity. Individual differences in sAA were positively associated with approach behavior and positive affect; whereas, cortisol was positively associated with negative affect and withdrawal behavior. The findings suggest that individual differences in sAA may covary specifically with positive affect and approach behaviors or the predominant emotional state across a series of tasks. The results are discussed with respect to advancing biosocial models of the concomitants and correlates of young children's affective behaviors.

Fearful Temperament and Stress Reactivity Among Preschool-Aged Children

In this study, we examined the relation between physiological stress-reactivity and temperamental fearfulness in 162 preschool-aged children. Both the autonomic and neuroendocrine arms of the mammalian stress system were examined. Larger stress responses were defined as greater sympathetic activation, parasympathetic withdrawal and cortisol increases to stressor tasks. Fearful temperament was examined using parent report and behavior in response to fear-evocative laboratory tasks. There was little evidence that larger sympathetic activation or parasympathetic withdrawal was associated with fearful temperament. Greater cortisol reactivity, however, was associated with fearful temperament. Additional analyses examined those children who were consistently fearful across all measures, and the results remained largely the same. However, there was some suggestion that consistently fearful compared to non-fearful children might be more likely to exhibit sympathetic activation to the fear-evocative stimuli. These findings provide support for the argument that fearful temperament is associated with greater stress reactivity in young children. Nonetheless the size of the associations was small and future studies will need to determine whether reactivity of stress-sensitive physiological systems contributes to the development of individual differences in fearful temperament or merely reflects these differences.

The polyvagal perspective

The polyvagal theory introduced a new perspective relating autonomic function to behavior, that included an appreciation of the autonomic nervous system as a "system," the identification of neural circuits involved in the regulation of autonomic state, and an interpretation of autonomic reactivity as adaptive within the context of the phylogeny of the vertebrate autonomic nervous system. The paper has two objectives: first, to provide an explicit statement of the theory; and second, to introduce the features of a polyvagal perspective. The polyvagal perspective emphasizes how an understanding of neurophysiological mechanisms and phylogenetic shifts in neural regulation leads to different questions, paradigms, explanations, and conclusions regarding autonomic function in biobehavioral processes than peripheral models. Foremost, the polyvagal perspective emphasizes the importance of phylogenetic changes in the neural structures regulating the autonomic nervous system and how these phylogenetic shifts provide insights into the adaptive function and the neural regulation of the two vagal systems.