Temperament and emotion regulation: the role of autonomic nervous system reactivity

Annual Research Review: What processes are dysregulated among emotionally dysregulated youth? - a systematic review

Proliferation of the term "emotion dysregulation" in child psychopathology parallels the growing interest in processes that influence negative emotional reactivity. While it commonly refers to a clinical phenotype where intense anger leads to behavioral dyscontrol, the term implies etiology because anything that is dysregulated requires an impaired regulatory mechanism. Many cognitive, affective, behavioral, neural, and social processes have been studied to improve understanding of emotion dysregulation. Nevertheless, the defective regulatory mechanism that might underlie it remains unclear. This systematic review of research on processes that affect emotion dysregulation endeavors to develop an integrative framework for the wide variety of factors investigated. It seeks to ascertain which, if any, constitutes an impaired regulatory mechanism. Based on this review, we propose a framework organizing emotion-relevant processes into categories pertaining to stimulus processing, response selection and control, emotion generation, closed- or open-loop feedback-based regulation, and experiential influences. Our review finds scant evidence for closed-loop (automatic) mechanisms to downregulate anger arousal rapidly. Open-loop (deliberate) regulatory strategies seem effective for low-to-moderate arousal. More extensive evidence supports roles for aspects of stimulus processing (sensory sensitivity, salience, appraisal, threat processing, and reward expectancy). Response control functions, such as inhibitory control, show robust associations with emotion dysregulation. Processes relating to emotion generation highlight aberrant features in autonomic, endocrine, reward functioning, and tonic mood states. A large literature on adverse childhood experiences and family interactions shows the unique and joint effects of interpersonal with child-level risks. We conclude that the defective closed-loop regulatory mechanisms that emotion dysregulation implies require further specification. Integrating research on emotion-relevant mechanisms along an axis from input factors through emotion generation to corrective feedback may promote research on (a) heterogeneity in pathogenesis, (b) interrelationships between these factors, and (c) the derivation of better-targeted treatments that address specific pathogenic processes of affected youth.

Effects of prenatal opioid exposure on infant sympathetic and parasympathetic nervous system activity

Prenatal opioid exposure has been associated with developmental problems, including autonomic nervous system dysregulation. However, little is known about the effects of prenatal opioid exposure on the autonomic nervous system beyond the first days of life, particularly across both the parasympathetic and sympathetic branches, and when accounting for exposure to other substances. The present study examined the effects of prenatal exposure to opioid agonist therapy (OAT, e.g., methadone) and other opioids on infant autonomic nervous system activity at rest and in response to a social stressor (the Still-Face Paradigm) at six months among 86 infants varying in prenatal opioid and other substance exposure. Results indicated that OAT and other opioids have unique effects on the developing autonomic nervous system that may further depend on subtype (i.e., methadone versus buprenorphine) and timing in gestation. Results are discussed in the context of theoretical models of the developing stress response system.

Parental sensitivity, family alliance and infants' vagal tone: Influences of early family interactions on physiological emotion regulation

In this study, we investigated the influence of parental sensitivity and family alliance on infants' vagal tone, considered as a physiological indicator of emotion regulation. Studies on mother-infant interactions have shown that vagal tone can be influenced by the quality of the interaction, such as interacting with a sensitive mother. To date, no study has investigated the influence of paternal sensitivity or family alliance on infants' vagal tone. We hypothesized that maternal sensitivity, paternal sensitivity, and family alliance would be associated with infants' vagal tone during dyadic and triadic interactions. We also explored if family alliance would act as a moderator on the association between parental sensitivity and vagal tone and if the sensitivity of both parents would act as a moderator on the association between family alliance and vagal tone. This study took place in Switzerland and included 82 families with their 3-4-month-old infants. Results showed that maternal sensitivity and family alliance were associated with infants' vagal tone, but paternal sensitivity was not. We found no significant moderation effect. However, result tendencies suggested that the contribution of paternal sensitivity to infants' emotion regulation could be influenced by family alliance, whereas maternal sensitivity and family alliance have a unique contribution.

The influence of the COVID-19 lockdown on infants' physiological regulation during mother-father-infant interactions in Switzerland

In this study, we investigated the physiological regulation of vagal tone during dyadic and triadic parent-infant interactions in infants born before or around the COVID-19 lockdown in Switzerland. We hypothesized that there would be a decrease in vagal tone in triadic interactions compared with dyadic interactions, as triadic interactions are more complex and therefore more resource demanding. However, we expected this difference to be smaller for infants who experienced the period of confinement, as the lockdown led parents to spend more time at home. We also hypothesized that parents would have less stressful interactional events in the triadic interaction because they would be used to interacting with the child together. This study included 36 parents with their 3 month-old infants. Eighteen families met the study authors before the onset of the pandemic (pre-COVID) and 18 met them after its onset, having experienced a period of confinement during the infants' first 3 months of life (COVID). Results showed that the COVID group had no decrease in vagal tone during triadic interactions, whereas the pre-COVID group did. This difference could not, however, be explained by less stressful interactional events in triadic interactions, as the COVID group showed more stressful interactional events in mother-father-infant interactions.

Autonomic nervous system activity moderates associations between temperament and externalizing behaviors in early childhood

Temperamental risk, such as surgency, negative affect, and poor effortful control, has been posited as a predictor of externalizing symptom development. However, autonomic nervous system (ANS) activity underlying processes of reactivity and regulation may moderate associations between early temperament and later externalizing behaviors during early childhood. The aim of the present study was to examine how interactions between resting sympathetic (SNS) and parasympathetic (PNS) activity at age 5 may moderate associations between temperamental risk at age 3 and externalizing behavior at age 6 (n = 87). Results demonstrate different interactions between resting ANS activity and temperamental risk to predict externalizing behaviors. For children with lower SNS activation at rest, surgency was positively associated with externalizing behaviors. Negative affect was positively associated with externalizing behaviors except when there were either high levels of SNS and PNS activity or low levels of SNS and PNS activity. Effortful control was not associated with externalizing behaviors, though SNS and PNS activity interacted to predict externalizing behaviors after accounting for effortful control. Taken together, the results highlight the importance to examine multisystem resting physiological activity as a moderator of associations between temperamental risk and the development of externalizing  behaviors.

A systematic review and meta-analysis of the association between parenting and child autonomic nervous system activity

Parental socialization may influence the development of children's autonomic nervous system (ANS), a key stress-response system. However, to date no quantitative synthesis of the literature linking parenting and child ANS physiology has been conducted. To address this gap, we conducted a pre-registered meta-analysis. A systematic review of the literature identified 103 studies (n = 13,044 participants) with available effect sizes describing the association between parenting and either parasympathetic nervous system (PNS) or sympathetic nervous system (SNS) activity in children. The overall analysis revealed non-significant associations between parenting and child ANS physiology on average. However, moderation analyses revealed a positive association between more positive parenting and higher resting PNS activity that was stronger when a study was experimental rather than correlational, and when the sample included children with a clinical condition. In conclusion, well-controlled experimental studies show that positive parenting is associated with the development of higher resting PNS activity, an effect that may be stronger among children who are at elevated developmental risk.

Examining a developmental pathway from early behavioral inhibition to emotion regulation and social anxiety: The moderating role of parenting

We examined the longitudinal relation between behavioral inhibition (BI) and social anxiety symptoms and behavior and the mediating role of emotion regulation (ER). Moreover, we investigated the influence of parenting behavior on the development of ER strategies. Participants were 291 children (135 male) followed longitudinally from 2 to 13 years. Mothers were predominantly well educated and non-Hispanic Caucasian. Children were screened for BI using maternal report and observational measures (ages 2 and 3), parenting behavior was observed while children and their mothers participated in a fear-eliciting task (age 3), ER strategies were observed while children completed a disappointment task (age 5), and socially anxious behavior was measured via multimethod assessment at 10 and 13 years. Children who exhibited high BI in early childhood exhibited more socially anxious behavior across ages 10 and 13, and there was a significant indirect effect of BI on socially anxious behavior through ER strategies. Children who were high in BI demonstrated less engaged ER strategies during the disappointment task, which in turn predicted more socially anxious behavior. Furthermore, parenting behavior moderated the pathway linking early BI and ER strategies to social anxiety outcomes such that children who exhibited high BI and who received more affectionate/oversolicitous behavior from their mother displayed less engaged ER strategies and more socially anxious behavior than children low in BI or low in oversolicitous parenting behaviors. These findings expand on our understanding of the role that ER strategies and parenting play in the developmental pathway linking early BI to future social anxiety outcomes. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

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.

The Complex Associations Between Early Childhood Adversity, Heart Rate Variability, Cluster B Personality Disorders, and Aggression

Early childhood adversity can cause an imbalance in the autonomic function, which may in turn lead to the development of trauma-spectrum disorders and aggressive behavior later in life. In the present study, we investigated the complex associations between early adversity, heart rate variability (HRV), cluster B personality disorders, and self-reported aggressive behavior in a group of 50 male forensic inpatients (M age = 41.16; SD = 10.72). Structural Equation Modeling analysis revealed that patients with cluster B personality disorders were more likely to have adverse early childhood experiences and reduced sympathetic dominance in response to a threat than patients without cluster B personality disorders. In addition, HRV and cluster B personality disorders did not significantly mediate the association between early childhood adversity and self-reported aggressive behavior. These findings are important for clinical practice to facilitate specific treatment programs for those affected.

Observational measures of early irritability predict children's psychopathology risk

Irritability is a transdiagnostic feature of diverse forms of psychopathology and a rapidly growing literature implicates the construct in child maladaptation. However, most irritability measures currently used are drawn from parent-report questionnaires not designed to measure irritability per se; furthermore, parent report methods have several important limitations. We therefore examined the utility of observational ratings of children's irritability in predicting later psychopathology symptoms. Four-hundred and nine 3-year-old children (208 girls) completed observational tasks tapping temperamental emotionality and parents completed questionnaires assessing child irritability and anger. Parent-reported child psychopathology symptoms were assessed concurrently to the irritability assessment and when children were 5 and 8 years old. Children's irritability observed during tasks that did not typically elicit anger predicted their later depressive and hyperactivity symptoms, above and beyond parent-reported irritability and context-appropriate observed anger. Our findings support the use of observational indices of irritability and have implications for the development of observational paradigms designed to assess this construct in childhood.

Maternal substance use disorder predicting children's emotion regulation in middle childhood: the role of early mother-infant interaction

Background

Maternal prenatal substance use disorder (SUD) represents a dual risk for child wellbeing due to teratogenic impacts and parenting problems often inherent in SUD. One potential mechanism transferring this risk is altered development of children's emotion regulation (ER). The present study examines how mother's prenatal SUD and early mother-infant interaction quality predict children's ER in middle childhood.

Method

The participants were 52 polysubstance using mothers and 50 non-users and their children. First-year mother-infant interaction quality was assessed with the Emotional Availability (EA) Scales and children's ER with the Children's Emotion Management Scales (CEMS), and its parent version (P-CEMS) at 8–12 years.

Results

Mother's prenatal SUD predicted a low level of children's adaptive ER strategies, whereas early mother-infant interaction problems predicted a high level of emotion dysregulation. The dyadic interaction also mediated the effect of SUD on emotion dysregulation. In the SUD group, more severe substance use predicted high emotion inhibition.

Conclusion

Early mother-infant interaction quality is critical in shaping children's ER, also in middle-childhood. Interventions aimed for mothers with prenatal SUD should integrate parenting components to support the optimal development of multiply vulnerable children.

The role of positive emotion dysregulation in the relationship between childhood abuse and PTSD in a community sample of veterans

BACKGROUND

The co-occurrence of childhood abuse and posttraumatic stress disorder (PTSD) among United States military veterans is highly prevalent and clinically significant. Emotion dysregulation is one factor that has been found to underlie the association between childhood abuse and PTSD, yet past research has focused exclusively on dysregulation stemming from negative emotions.

OBJECTIVE

The current study extends existing research by clarifying the role of positive emotion dysregulation in the relation between childhood abuse and PTSD in a community sample of military veterans.

PARTICIPANTS AND SETTING

Participants were 465 trauma-exposed military veterans in the community (Mage = 38.00, 71.6 % women, 69.5 % White).

METHOD

Using structural equation modeling, we tested the indirect association of childhood abuse to PTSD symptom severity through positive emotion dysregulation.

RESULTS

The hypothesized model showed adequate model fit, χ2 (32, n = 465) = 176.22, p < .001, CFI = .97, RMSEA = .10, 90 % CI [.08, .11], SRMR = .04. Results showed that childhood abuse was indirectly associated with PTSD symptom severity through positive emotion dysregulation.

CONCLUSIONS

This finding highlights the potential utility of targeting positive emotion dysregulation in the detection and treatment of PTSD symptoms in veterans who experienced childhood abuse.

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.

Talking about emotions: Effects of emotion-focused interviewing on children's physiological regulation of stress and discussion of the subjective elements of a stressful experience

This is the first study to examine the effect of questioning children about emotions and cognitions versus facts on children's stress reactivity and regulation, as well as children's abilities to discuss their subjective experiences, in the context of adult-child discussions about a stressful event. A total of 80 8- to 12-year-old children participated in a stressful laboratory task (i.e., Trier Social Stress Test). Following the task, half of the children were engaged in an emotion-focused conversation with an adult interviewer about the event, and half were engaged in a fact-focused conversation. Electrodermal and cardiac preejection activity and respiratory sinus arrhythmia were derived at baseline, during the laboratory stressor, and during the conversation to index stress reactivity and regulation. Children's narratives were coded for indicators of emotion processing (i.e., positive and negative emotion words, cognitive words [e.g., think, know]). Children's English language abilities, self-reported stress, and several parent-report measures (demographics, child life stress, and children's emotion regulation strategies) were also obtained. Results indicate that the emotion-focused interview facilitated children's discussions of their subjective experiences without increasing their stress reactivity and that children showed enhanced physiological stress regulation during the emotion-focused interview. This research will be of interest to those in the fields of child narratives, stress, and social context as well as to parents and practitioners interested in improving children's understanding, reporting, and recovery after stressful experiences.

Behavioral and Autonomic Responses in Treating Children with High-Functioning Autism Spectrum Disorder: Clinical and Phenomenological Insights from Two Case Reports

In this study, we aimed to evaluate the process applied in subjects with Autism Spectrum Disorder (ASD) to elaborate and communicate their experiences of daily life activities, as well as to assess the autonomic nervous system response that subtend such a process. This procedure was evaluated for the first time in two eight-year-old girls with high-functioning ASDs. The subjects performed six months of training, based on the cognitive–motivational–individualized (c.m.i.^®) approach, which mainly consisted in building domestic procedures and re-elaborating acquired experiences through drawing or the use of icons made by the children. Together with behavioral observations, the response of the autonomic nervous system during such re-elaboration was recorded. A change in communicative and interactive competences was observed, moving from a condition of spontaneity to one in which the girls were engaged in relating their experiences to a parent. Autonomic response highlighted how, in communicating their own experiences, they achieved a state of cognitive activation, which enabled a greater communicative and emotional connection with the interlocutor. This is a proof-of-concept study on the application of the c.m.i.^®, which needs to be extensively validated in the clinical setting.

Infant emotional responses to challenge predict empathic behavior in toddlerhood

Although emotional responses are theorized to be important in the development of empathy, findings regarding the prediction of early empathic behavior by infant behavioral and physiological responses are mixed. This study examined whether behavioral and physiological responses to mild emotional challenge (still face paradigm and car seat task) in 118 infants at age 6 months predicted empathic distress and empathic concern in response to an empathy-evoking task (i.e, experimenter's distress simulation) at age 20 months. Correlation analyses, corrected for sex and baseline levels of physiological arousal, showed that stronger physiological and behavioral responses to emotional challenge at age 6 months were positively related to observed empathic distress, but not empathic concern, at age 20 months. Linear regression analyses indicated that physiological and behavioral responses to challenge at 6 months independently predicted empathic distress at 20 months, which suggests an important role for both physiological and behavioral emotional responses in empathy development. In addition, curvilinear regression analyses showed quadratic associations between behavioral responses at 6 months, and empathic distress and empathic concern at 20 months, which indicates that moderate levels of behavioral responsivity predict the highest levels of empathic distress and empathic concern.

Reduced caregiving quality measured during the strange situation procedure increases child's autonomic nervous system stress response

BACKGROUND

Dysfunctional maternal behavior has been shown to lead to disturbances in infant's regulatory capacities and alterations in vagal reactivity. We aim to investigate the autonomic nervous system (ANS) response of the child during the strange situation procedure (SSP) in relation to the quality of maternal behavior.

METHODS

Twelve month after birth, 163 mother-child-dyads were investigated during the SSP. Heart rate (HR) and both, the parasympathetic branch (PNS) via the respiratory sinus arrhythmia (RSA) and the sympathetic branch (SNS) via the left ventricular ejection time (LVET) of the ANS were continuously determined during the SSP using electrocardiogram (ECG) and impedance cardiogram (ICG) measures. Maternal behavior was assessed by using the AMBIANCE measure.

RESULTS

The ANS response in infants of mothers with disruptive behavior compared to infants of non-disruptive mothers was significantly altered during the SSP: HR increased especially when infants of disruptive mothers were alone with the stranger (F (1, 161) = 4.15, p = .04) with a significant vagal withdrawal when being in contact with the stranger despite of presence of the mother (F (1, 161) = 5.11, p = .03) and a significant increase in vagal tone during final reunion (F (1, 161) = 3.76, p = .05). HR increase was mainly based on a decrease in LVET (F (1, 161) = 4.08, p = .05) with a maximum infant's HR when the stranger came into the room instead of the mother.

CONCLUSION

Both, SNS and PNS branches of the child are significantly altered in terms of an ANS imbalance, especially during contract to a stranger, in relation to dysfunctional maternal behavior. Our findings suggest the importance of supporting high quality caregiving that enables the infant to adapt adequately to stressful interpersonal situations which is likely to promote later health.

Autonomic complexity and emotion (dys-)regulation in early childhood across high- and low-risk contexts

Developing the ability to regulate one's emotions in accordance with contextual demands (i.e., emotion regulation) is a central developmental task of early childhood. These processes are supported by the engagement of the autonomic nervous system (ANS), a physiological hub of a vast network tasked with dynamically integrating real-time experiential inputs with internal motivational and goal states. To date, much of what is known about the ANS and emotion regulation has been based on measures of respiratory sinus arrhythmia, a cardiac indicator of parasympathetic activity. In the present study, we draw from dynamical systems models to introduce two nonlinear indices of cardiac complexity (fractality and sample entropy) as potential indicators of these broader ANS dynamics. Using data from a stratified sample of preschoolers living in high- (i.e., emergency homeless shelter) and low-risk contexts (N = 115), we show that, in conjunction with respiratory sinus arrhythmia, these nonlinear indices may help to clarify important differences in the behavioral manifestations of emotion regulation. In particular, our results suggest that cardiac complexity may be especially useful for discerning active, effortful emotion regulation from less effortful regulation and dysregulation.

Infant Parasympathetic and Sympathetic Activity during Baseline, Stress and Recovery: Interactions with Prenatal Adversity Predict Physical Aggression in Toddlerhood

Exposure to prenatal adversity is associated with aggression later in life. Individual differences in autonomic nervous system (ANS) functioning, specifically nonreciprocal activation of the parasympathetic (PNS) and sympathetic (SNS) nervous systems, increase susceptibility to aggression, especially in the context of adversity. Previous work examining interactions between early adversity and ANS functioning in infancy is scarce and has not examined interaction between PNS and SNS. This study examined whether the PNS and SNS moderate the relation between cumulative prenatal risk and early physical aggression in 124 children (57% male). Cumulative risk (e.g., maternal psychiatric disorder, substance (ab)use, and social adversity) was assessed during pregnancy. Parasympathetic respiratory sinus arrhythmia (RSA) and sympathetic pre-ejection period (PEP) at baseline, in response to and during recovery from emotional challenge were measured at 6 months. Physical aggression and non-physical aggression/oppositional behavior were measured at 30 months. The results showed that cumulative prenatal risk predicted elevated physical aggression and non-physical aggression/oppositional behavior in toddlerhood; however, the effects on physical aggression were moderated by PNS and SNS functioning. Specifically, the effects of cumulative risk on physical aggression were particularly evident in children characterized by low baseline PNS activity and/or by nonreciprocal activity of the PNS and SNS, characterized by decreased activity (i.e., coinhibition) or increased activity (i.e., coactivation) of both systems at baseline and/or in response to emotional challenge. These findings extend our understanding of the interaction between perinatal risk and infant ANS functioning on developmental outcome.

Marital conflict and trajectories of adolescent adjustment: The role of autonomic nervous system coordination

The present study investigates how coordination between stress responsivity of the parasympathetic nervous system (PNS) and sympathetic nervous system (SNS) moderates the prospective effects of marital conflict on internalizing and externalizing symptoms across adolescence. Although an important avenue for psychophysiological research concerns how PNS and SNS responses jointly influence adjustment in the context of stress, these processes have rarely been studied in adolescence or longitudinally. Participants were 252 youth (53% female, 66% European American, 34% African American) who participated in laboratory assessments when they were 16, 17, and 18 years old. PNS activity (measured via respiratory sinus arrhythmia [RSA]) and SNS activity (measured via skin conductance level [SCL]) were assessed during a resting baseline and in response to a laboratory-based challenge (star tracing). Parents and adolescents both reported on marital conflict and adolescents reported on their internalizing and externalizing symptoms. At higher levels of marital conflict, coactivation of PNS and SNS activity, characterized by increased RSA and increased SCL from baseline to challenge, predicted elevated internalizing symptoms and an increase in externalizing behavior across adolescence. Coinhibition, or decreased activity across both systems, also predicted an increase in internalizing symptoms over time. At lower levels of marital conflict, internalizing and externalizing symptoms were relatively low. Findings extend primarily cross-sectional work with younger children by demonstrating that coordination between the two branches of the autonomic nervous system (ANS) moderates the longitudinal effects of marital conflict on psychological and behavioral maladjustment among adolescents. (PsycINFO Database Record

Negative association between resilience and event-related potentials evoked by negative emotion

Individuals with low level of resilience are documented to be less capable of regulating negative emotion. To investigate the underlying neurophysiology, the present study examined the relationship between resilience and the late positive potential (LPP) evoked by emotionally negative pictures. Fifty-four participants watched negative and neutral pictures passively while their electroencephalogram (EEG) was recorded to assess LPP. Participants also completed the Connor-Davidson Resilience Scale (CD-RISC) for assessment of their resilience levels. We found that resilience was negatively correlated with the LPP response to negative emotional pictures. Additionally, this negative correlation was mainly driven by optimism, one of the three composite factors that contribute to resilience. Our results showed a neurophysiological correlate for the effect of resilience on negative emotion, and suggested a predictive value of optimism in identifying individuals potentially sensitive to affective interruptions.

Heart Rate Variability During a Joint Attention Task in Toddlers With Autism Spectrum Disorders

Background: Autism Spectrum Disorders (ASD) are a heterogeneous group of neurodevelopmental disorders featuring early impairments in social domain, with autonomic nervous system (ANS) unbalance possibly representing a useful marker for such disturbances. Impairments in joint attention (JA) are one of the earliest markers of social deficits in ASD. In this study, we assessed the feasibility of using wearable technologies for characterizing the ANS response in ASD toddlers during the presentation of JA stimuli. Methods: Twenty ASD toddlers and 20 age- and gender-matched typically developed (TD) children were recorded at baseline and during a JA task through an unobtrusive chest strap for electrocardiography (ECG). Specific algorithms for feature extraction, including Heart Rate (HR), Standard Deviation of the Normal-to-Normal Intervals (SDNN), Coefficient of Variation (CV), pNN10 as well as low frequency (LF) and high frequency (HF), were applied to the ECG signal and a statistical comparison between the two groups was performed. Results: As regards the single phases, SDNN (p = 0.04) and CV (p = 0.021) were increased in ASD at baseline together with increased LF absolute power (p = 0.034). Moreover, CV remained higher in ASD during the task (p = 0.03). Considering the phase and group interaction, LF increased from baseline to task in TD group (p = 0.04) while it decreased in the ASD group (p = 0.04). Conclusions: The results of this study indicate the feasibility of characterizing the ANS response in ASD toddlers through a minimally obtrusive tool. Our analysis showed an increased SDNN and CV in toddlers with ASD particularly at baseline compared to TD and lower LF during the task. These findings could suggest the possibility of using the proposed approach for evaluating physiological correlates of JA response in young children with ASD.

Altered Resting-State Brain Activities in Drug-Naïve Major Depressive Disorder Assessed by fMRI: Associations With Somatic Symptoms Defined by Yin-Yang Theory of the Traditional Chinese Medicine

Identification of biological markers for defining subtypes of major depressive disorder (MDD) is critical for better understanding MDD pathophysiology and finding effective treatment intervention. The "Yin and Yang" theory is a fundamental concept of traditional Chinese Medicine (TCM). The theory differentiates MDD patients into two subtypes, Yin and Yang, based on their somatic symptoms, which had empirically been used for the delivery of effective treatment in East Asia. Nonetheless, neural processes underlying Yin and Yang types in MDD are poorly understood. In this study, we aim to provide physiological evidence using functional magnetic resonance imaging (fMRI) to identify altered resting-state brain activity associated with Yin and Yang types in drug-naïve MDD patients. The Yin type and Yang type MDD patients showed increased amplitude of low-frequency fluctuation (ALFF) in different cortical brain areas in the parietal, temporal, and frontal lobe, compared to matched healthy controls. Differential ALFF is also observed in several cortical areas in frontal lobe and insula between Yin and Yang type group. Of note, although ALFF is increased in the inferior parietal lobe in both Yin and Yang type group, inferior parietal lobe-centered functional connectivity (FC) is increased in Yang type, but is decreased in Ying type, compared with matched healthy controls. These results suggest that differential resting-state brain activity and functional connectivity in Yin and Yang types may contribute to biological measures for better stratification of heterogeneous MDD patients.

Interaction between prenatal risk and infant parasympathetic and sympathetic stress reactivity predicts early aggression

Nonreciprocal action of the parasympathetic (PNS) and sympathetic (SNS) nervous systems, increases susceptibility to emotional and behavioral problems in children exposed to adversity. Little is known about the PNS and SNS in interaction with early adversity during infancy. Yet this is when the physiological systems involved in emotion regulation are emerging and presumably most responsive to environmental influences. We examined whether parasympathetic respiratory sinus arrhythmia (RSA) and sympathetic pre-ejection period (PEP) response and recovery at six months, moderate the association between cumulative prenatal risk and physical aggression at 20 months (N=113). Prenatal risk predicted physical aggression, but only in infants exhibiting coactivation of PNS and SNS (i.e., increase in RSA and decrease in PEP) in response to stress. These findings indicate that coactivation of the PNS and SNS in combination with prenatal risk is a biological marker for the development of aggression.

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.

Altered Pre-Ejection Period Response to Social Evaluative Threat in Adolescents with Autism Spectrum Disorder

INTRODUCTION

The autonomic nervous system (ANS) is involved in regulating social behavior; Autism Spectrum Disorder (ASD) is characterized by alterations in social behavior and reduced physiological response to threat. We hypothesized that adolescents with ASD would show reduced ANS response to social threat.

METHODS

Eighteen males with ASD and thirteen males with typical development (TD), ages 12 to 17, completed a social threat paradigm while wearing an impedance cardiography apparatus. We calculated pre-ejection period (PEP) and tested for between-group differences in PEP response to social threat. We also conducted correlation analyses between PEP change scores and clinical symptom scales.

RESULTS

There was an effect of diagnosis on change in PEP from baseline to the onset of social threat (F=7.60, p=0.01), with greater changes in PEP in TD compared to ASD. PEP change score and the Social Communication Questionnaire (r=0.634, p=0.005) and the ADHD Problems Subscale of the Child Behavior Checklist (r=0.568, p=0.014) were correlated.

CONCLUSIONS

These findings suggest reduced arousal in response to social threat in ASD, with preliminary evidence that reduced sympathetic activation is associated with increased social behavior symptoms.

Measuring Cardiac Autonomic Nervous System (ANS) Activity in Toddlers - Resting and Developmental Challenges

The autonomic nervous system (ANS) consists of two branches, the parasympathetic and sympathetic nervous systems, and controls the function of internal organs (e.g., heart rate, respiration, digestion) and responds to everyday and adverse experiences (1). ANS measures in children have been found to be related to behavior problems, emotion regulation, and health (2-7). Therefore, understanding the factors that affect ANS development during early childhood is important. Both branches of the ANS affect young children's cardiovascular responses to stimuli and have been measured noninvasively, via external monitoring equipment, using valid and reliable measures of physiological change (8-11). However, there are few studies of very young children with simultaneous measures of the parasympathetic and sympathetic nervous systems, which limits understanding of the integrated functioning of the two systems. In addition, the majority of existing studies of young children report on infants' resting ANS measures or their reactivity to commonly used mother-child interaction paradigms, and less is known about ANS reactivity to other challenging conditions. We present a study design and standardized protocol for a non-invasive and rapid assessment of cardiac autonomic control in 18 month old children. We describe methods for continuous monitoring of the parasympathetic and sympathetic branches of the ANS under resting and challenge conditions during a home or laboratory visit and provide descriptive findings from our sample of 140 ethnically diverse toddlers using validated equipment and scoring software. Results revealed that this protocol can produce a range of physiological responses to both resting and developmentally challenging conditions, as indicated by changes in heart rate and indices of parasympathetic and sympathetic activity. Individuals demonstrated variability in resting levels, responses to challenges, and challenge reactivity, which provides additional evidence that this protocol is useful for the examination of ANS individual differences for toddlers.

Relational victimization and proactive versus reactive relational aggression: The moderating effects of respiratory sinus arrhythmia and skin conductance

This research examined the moderating effect of the autonomic nervous system (ANS) on the associations between relational victimization and reactive and proactive relational aggression. Both branches of the ANS, the parasympathetic nervous system (indexed by respiratory sinus arrhythmia reactivity; RSA-Reactivity) and the sympathetic nervous system (indexed by skin conductance level reactivity; SCL-Reactivity), were examined. Emerging adults (N = 168) self-reported on relational victimization and proactive and reactive relational aggression; RSA-Reactivity and SCL-Reactivity were assessed in response to a laboratory stressor. Relational victimization predicted heightened reactive relational aggression given RSA augmentation/high SCL-Reactivity (i.e., coactivation) and RSA withdrawal/low SCL-Reactivity (i.e., coinhibition). In addition, relational victimization predicted heightened reactive relational aggression given RSA augmentation/low SCL-Reactivity (i.e., reciprocal parasympathetic activation). This study extends previous research on relational victimization and provides novel evidence that (a) exposure to relational victimization is associated with reactive relational aggression, but not proactive relational aggression, and (b) parasympathetic and sympathetic nervous system reactivity jointly moderate the link between relational victimization and reactive relational aggression.

Linking bioregulatory systems: reciprocal autonomic activation predicts sleep over 1 year in middle childhood

This study examined reactivity to social-evaluative stress in the parasympathetic (PNS) and sympathetic (SNS) branches of the autonomic nervous system (ANS) as prospective predictors of sleep in middle childhood. Participants included 339 children (M age = 9 years and 5 months at T1; 54% female; 64% European American, 36% African American). Sleep efficiency, sleep minutes, and variability in sleep onset time were assessed with actigraphy for seven consecutive nights at T1 and 1 year later at T2. Respiratory sinus arrhythmia reactivity (RSAR) and skin conductance level reactivity (SCLR) were assessed in response to a developmentally salient social-evaluative stress task at T1. Controlling for demographic variables and the respective sleep parameter at T1, the interaction between RSAR and SCLR predicted T2 sleep efficiency and sleep minutes. Consistent with the hypothesized role of reciprocal sympathetic activation (higher SCLR) and parasympathetic withdrawal (higher RSAR), higher RSAR predicted higher sleep efficiency and sleep minutes among children with higher SCLR but not lower SCLR.

Subtyping attention-deficit/hyperactivity disorder using temperament dimensions: toward biologically based nosologic criteria

IMPORTANCE

Psychiatric nosology is limited by behavioral and biological heterogeneity within existing disorder categories. The imprecise nature of current nosologic distinctions limits both mechanistic understanding and clinical prediction. We demonstrate an approach consistent with the National Institute of Mental Health Research Domain Criteria initiative to identify superior, neurobiologically valid subgroups with better predictive capacity than existing psychiatric categories for childhood attention-deficit/hyperactivity disorder (ADHD).

OBJECTIVE

To refine subtyping of childhood ADHD by using biologically based behavioral dimensions (i.e., temperament), novel classification algorithms, and multiple external validators.

DESIGN, SETTING, AND PARTICIPANTS

A total of 437 clinically well-characterized, community-recruited children, with and without ADHD, participated in an ongoing longitudinal study. Baseline data were used to classify children into subgroups based on temperament dimensions and examine external validators including physiological and magnetic resonance imaging measures. One-year longitudinal follow-up data are reported for a subgroup of the ADHD sample to address stability and clinical prediction.

MAIN OUTCOMES AND MEASURES

Parent/guardian ratings of children on a measure of temperament were used as input features in novel community detection analyses to identify subgroups within the sample. Groups were validated using 3 widely accepted external validators: peripheral physiological characteristics (cardiac measures of respiratory sinus arrhythmia and pre-ejection period), central nervous system functioning (via resting-state functional connectivity magnetic resonance imaging), and clinical outcomes (at 1-year longitudinal follow-up).

RESULTS

The community detection algorithm suggested 3 novel types of ADHD, labeled as mild (normative emotion regulation), surgent (extreme levels of positive approach-motivation), and irritable (extreme levels of negative emotionality, anger, and poor soothability). Types were independent of existing clinical demarcations including DSM-5 presentations or symptom severity. These types showed stability over time and were distinguished by unique patterns of cardiac physiological response, resting-state functional brain connectivity, and clinical outcomes 1 year later.

CONCLUSIONS AND RELEVANCE

Results suggest that a biologically informed temperament-based typology, developed with a discovery-based community detection algorithm, provides a superior description of heterogeneity in the ADHD population than does any current clinical nosologic criteria. This demonstration sets the stage for more aggressive attempts at a tractable, biologically based nosology.

Lost among the trees? The autonomic nervous system and paediatrics

The autonomic nervous system (ANS) has been strikingly neglected in Western medicine. Despite its profound importance for regulation, adjustment and coordination of body systems, it lacks priority in training and practice and receives scant attention in numerous major textbooks. The ANS is integral to manifestations of illness, underlying familiar physical and psychological symptoms. When ANS activity is itself dysfunctional, usual indicators of acute illness may prove deceptive. Recognising the relevance of the ANS can involve seeing the familiar through fresh eyes, challenging assumptions in clinical assessment and in approaches to practice. Its importance extends from physical and psychological well-being to parenting and safeguarding, public services and the functioning of society. Exploration of its role in conditions ranging from neurological, gastrointestinal and connective tissue disorders, diabetes and chronic fatigue syndrome, to autism, behavioural and mental health difficulties may open therapeutic avenues. The ANS offers a mechanism for so-called functional illnesses and illustrates the importance of recognising that 'stress' takes many forms, physical, psychological and environmental, desirable and otherwise. Evidence of intrauterine and post-natal programming of ANS reactivity suggests that neonatal care and safeguarding practice may offer preventive opportunity, as may greater understanding of epigenetic change of ANS activity through, for example, accidental or psychological trauma or infection. The aim of this article is to accelerate recognition of the importance of the ANS throughout paediatrics, and of the potential physical and psychological cost of neglecting it.

Determining the impact of prenatal tobacco exposure on self-regulation at 6 months

Our goal in the present study was to examine the effects of maternal smoking during pregnancy on infant self-regulation, exploring birth weight as a mediator and sex as a moderator of risk. A prospective sample of 218 infants was assessed at 6 months of age. Infants completed a battery of tasks assessing working memory/inhibition, attention, and emotional reactivity and regulation. Propensity scores were used to statistically control for confounding risk factors associated with maternal smoking during pregnancy. After prenatal and postnatal confounds were controlled, prenatal tobacco exposure was related to reactivity to frustration and control of attention during stimulus encoding. Birth weight did not mediate the effect of prenatal exposure but was independently related to reactivity and working memory/inhibition. The effect of tobacco exposure was not moderated by sex.

Effects of perinatal oxycodone exposure on the cardiovascular response to acute stress in male rats at weaning and in young adulthood

Oxycodone (OXY) is one of the most commonly abused opiates during pregnancy. Perinatal opiate exposure (POE) is associated with neurobehavioral and hormone changes. Little is known about the effects of perinatal OXY on the cardiovascular (CV) responses to stress.

OBJECTIVES

to determine the effects of POE on: (1) CV responses to acute stress and ability to discriminate using a classical conditioning paradigm; (2) changes in CV response to the paradigm and retention of the ability to discriminate from postnatal day (PD) 40 to young adulthood.

METHODS

Pregnant rats were given i.v. OXY or vehicle (CON) daily. OXY and CON males were fitted with BP telemetry units. Offspring were classically conditioned by following a pulsed tone (CS+) with tail shock. A steady tone (CS-) was not followed by shock. BP and HR were recorded during resting periods and conditioning. Changes in BP, HR from composite analysis were compared. The paradigm was repeated on PD 75.

RESULTS

At PD 40, OXY rats had a lower baseline mean BP (OXY: 114.8 ± 1.0 vs. CON: 118.3 ± 1.0 mm Hg; mean ± SEM) but larger amplitude of the conditional BP increase during the stress response (OXY: +3.9 ± 0.4 vs. CON: +1.7 ± 0.4 mm Hg). Both OXY and CON rats were able to discriminate between CS+ and CS-. At PD 75, the effects of OXY on the increased amplitude of the conditional BP had dissipated (CON: +3.4 ± 2.3 vs. OXY: +4.5 ± 1.4 mm Hg). BP responses to the stress and non-stress stimuli did not differ in the OXY group, suggesting that OXY may have decreased the ability of the offspring to discriminate (OXY: CS+: 147.1 ± 1.6, CS-: 145.9 ± 1.6 mm Hg vs. CON: CS+: 155.4 ± 2.7, CS-: 147.8 ± 2.7 mm Hg).

CONCLUSION

POE is associated with subtle alterations in stress CV responses in weanling rats which dissipate when the conditioning is repeated at an early adult age. Although POE effect on the ability to discriminate at weanling age could not be detected, POE may impair retention of this ability in adulthood.

Physiological and self-assessed emotional responses to emotion-eliciting films in borderline personality disorder

According to Linehan's biosocial model, the core characteristic of borderline personality disorder (BPD) is emotional dysregulation. In the present study, we investigated two components of this model: baseline emotional intensity and emotional reactivity. A total of 60 women, 30 with BPD diagnosis and 30 age and sex-matched healthy subjects (HCs), participated in two experiments. In the first experiment, we evaluated emotional responses to six films designed to elicit discrete emotions (anger, fear, sadness, disgust, amusement and neutral). The second experiment evaluated emotional reactions to three emotion-eliciting films containing BPD-specific content (sexual abuse, emotional dependence and abandonment/separation). Skin conductance level, heart rate, and subjective emotional response were recorded for each film. Although self-reported data indicated that negative emotions at baseline were stronger in the BPD group, physiological measures showed no differences between the groups. Physiological results should be interpreted with caution since most BPD participants were under pharmacological treatment. BPD subjects presented no subjective heightened reactivity to most of the discrete emotion-eliciting films. Subjective responses to amusement and "BPD-specific content" films revealed significant between-group differences. These findings suggest that the main characteristic of BPD might be negative emotional intensity rather than heightened emotional reactivity.

Temperamental surgency and emotion regulation as predictors of childhood social competence

The primary aims of the current study were to longitudinally examine the direct relationship between children's temperamental surgency and social behaviors as well as the moderating role of children's emotion regulation. A total of 90 4.5-year-old children participated in a laboratory visit where children's temperamental surgency was rated by experimenters and children's emotion regulation abilities were assessed. The summer before entry into first grade, children's social behaviors with unfamiliar peers were observed in the laboratory and mothers completed a questionnaire about children's social behaviors. Supporting our hypotheses, results revealed that children high in temperamental surgency developed more negative peer behaviors, whereas children low in temperamental surgency were more likely to develop behavioral wariness with peers. Emotion regulatory behaviors were found to moderate the relation between temperamental surgency and aggression, where high-surgent children who showed high levels of social support seeking were less likely to be rated by their mothers as high in aggression. Furthermore, results revealed that low-surgent children who showed high levels of distraction/self-soothing were more likely to show behavioral wariness around unfamiliar peers, whereas high-surgent children who used more distraction/self-soothing behaviors were rated by their mothers as lower in social competence.