Vagal Flexibility Research Articles

Children’s vagal flexibility is a predictor and moderator of treatment response to early parenting interventions for inhibited youth

Behavioral inhibition (BI), a dispositional trait characterized by fear and withdrawal in the face of novelty, is a risk factor for the later diagnosis of anxiety; yet, not all inhibited children go on to develop anxiety disorders. Certain parenting behaviors moderate risk for anxiety among temperamentally inhibited youth, which has motivated the creation of early parenting interventions to mitigate this risk among young children high in BI. These programs vary in complexity, begging the question of who needs more or less intensive intervention. In addition, variability in children’s parasympathetic nervous system (PNS) functioning may provide insight into the substantial heterogeneity in anxiety outcomes for children high in BI. The current study investigates the role of vagal flexibility (VF), an index of non-linear change in PNS functioning, in children’s response to an early intervention for anxiety (ClinicalTrials.gov registration: NCT02308826). Participants ( n = 151, ages of 45–64 months) were randomized to participate in the Turtle Program (“Turtle”), a multi-component intervention comprising an adaptation of parent–child interaction therapy and social skills training, or Cool Little Kids (CLK), an established psychoeducational parenting intervention. Child participants also completed pre-, mid-, and post-treatment laboratory visits, which included a series of social stressor tasks preceded by a non-stressful but emotionally engaging video, during which cardiac physiology was recorded. Longitudinal latent profile analyses were used to identify latent non-linear trajectories of VF across the entire intervention (i.e., pre-, mid-, and post-treatment visits). Two latent classes were distinguished by the presence of high or low child VF across the treatment. Although VF class membership was not associated with intervention group membership, auxiliary within-class prediction models suggest that children who exhibited consistently greater VF demonstrated lower post-treatment clinician severity ratings of anxiety in Turtle, β = −0.21, p = .01, but not in CLK, β = 0.13, p = .39. Findings contribute to a broad literature demonstrating the utility of indices of PNS functioning in providing insight into risk for psychopathology and suggest that children’s VF moderates treatment response by supporting children’s ability to effectively engage in and extract benefits from intervention protocols. Implications for our understanding of the role children’s physiological regulation plays in the links between BI, parenting, risk for anxiety, and treatment response are discussed.

Disorders of gut-brain interaction through the lens of polyvagal theory.

This paper introduces a metric capable of tracking a hypothetical brainstem "switching" mechanism involved in regulating the afferent influence of blood pressure on the vagal efferent control of heart rate. In theory, this metric could be applied to evaluate the "efficiency" of brainstem pathways involved in common mechanisms of autonomic function involving the vagal influences on the gut as well as the heart. Thus, by exploring the dynamic "efficiency" of the brainstem feedback circuit linking heart rate to posture, a clinically relevant index of vagal flexibility might be extracted that would provide a generalizable window into the vagal regulation of both the heart and gut. Recent research supports this contention and has documented that this metric, VE, appears to covary with disorders of the gut. Clinical application of this metric might identify individual vulnerabilities that frequently reflect symptoms assumed to have features of a dysregulated autonomic nervous system (i.e., dysautonomia). If this is confirmed by additional research, then this objective measure of neural regulation of autonomic function might provide insight into the pathogenesis of disorders of gut-brain interaction.

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

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

Examining the Relations Between Children's Vagal Flexibility Across Social Stressor Tasks and Parent- and Clinician-Rated Anxiety Using Baseline Data from an Early Intervention for Inhibited Preschoolers.

Early behavioral inhibition (BI) is a known risk factor for later anxiety disorder. Variability in children's parasympathetic nervous system (PNS) functioning may provide insight into the substantial heterogeneity in anxiety outcomes for children high in BI. However, gaps persist due to an over-reliance on static measures of functioning, which limits our ability to leverage PNS functioning to identify risk for anxiety. We address these gaps using baseline data from an early intervention study of inhibited preschoolers by characterizing vagal flexibility (VF), an index of non-linear change in PNS functioning, across social stressor tasks and by examining the associations between VF and anxiety. One hundred and fifty-one parents and their 3.5- to 5-year-old children were selected on the basis of BI to participate in an early intervention program (ClinicalTrials.gov registration: NCT02308826). A structural equation modeling framework was used to model children's VF across tasks designed to mimic exposure to novel social interactions and to test the predictive links between VF and anxiety. Children who showed less VF, characterized by less suppression and flatter recovery, were rated by both parents and clinicians as more anxious. Moreover, a multiple group model showed that children meeting diagnostic criteria for social anxiety disorder demonstrated significantly less VF across social stressor tasks. Among inhibited youth, reduced VF is a risk factor for anxiety and may reflect an individual's reduced capacity to actively cope with external demands. Study results contribute to our understanding of the regulatory processes underlying risk for anxiety in early childhood.

Vagal flexibility to negative emotions moderates the relations between environmental risk and adjustment problems in childhood.

Neurobiological and social-contextual influences shape children's adjustment, yet limited biopsychosocial studies have integrated temporal features when modeling physiological regulation of emotion. This study explored whether a common underlying pattern of non-linear change in respiratory sinus arrhythmia (RSA) across emotional scenarios characterized 4-6 year-old children's parasympathetic reactivity (N = 180). Additionally, we tested whether dynamic RSA reactivity was an index of neurobiological susceptibility or a diathesis in the association between socioeconomic status, authoritarian parenting, and the development of externalizing problems (EP) and internalizing problems over two years. There was a shared RSA pattern across all emotions, characterized by more initial RSA suppression and a subsequent return toward baseline, which we call vagal flexibility (VF). VF interacted with parenting to predict EP. More authoritarian parenting predicted increased EP two years later only when VF was low; conversely, when VF was very high, authoritarian mothers reported that their children had fewer EP. Altogether, children's patterns of dynamic RSA change to negative emotions can be characterized by a higher order factor, and the nature by which VF contributes to EP depends on maternal socialization practices, with low VF augmenting and high VF buffering children against the effects of authoritarian parenting.

Exploring autonomic regulation in children with ADHD with and without comorbid anxiety disorder through three systematic levels of cardiac vagal control analysis: Rest, reactivity, and recovery.

Autonomic nervous system (ANS) dysregulation, characterized by reduced vagally mediated Heart Rate Variability (HRV), has been associated with Attention-Deficit/ Hyperactivity Disorder (ADHD). This study investigated the dynamic vagal modulation of cardiac output in response to shifts in environmental demands in children and adolescents with ADHD, with and without a comorbid anxiety disorder. High-frequency HRV (HF-HRV) measures were obtained from 46 children and adolescents ranging from 6 to 17 (M=9.38; SD = 2.31) years old, during three successive experimental conditions: a baseline recording followed by a sustained attention task, and a post-task recovery period. Findings support the reliability of the d2 Test, a cancelation test of attention and concentration, to induce parasympathetic withdrawal and extend prior work on "vagal flexibility". Further, these findings suggest a pattern of group differences in ANS functioning in children with ADHD, with and without a comorbid anxiety disorder. Only the ADHD without comorbid anxiety group showed a normative autonomic response to the cognitive challenge (reduced HF-HRV). The participants did not display an adaptive process of restoration following the cognitive challenge; the HRV suppression was prolonged during post-task recovery period, suggesting that ANS responded as if the cognitive stressor was still present. The current paper covers and discusses theoretical implications for the abnormalities in neurophysiological functioning and the different physiological responses in the two ADHD subtypes.

The Development of Generosity From 4 to 6 Years: Examining Stability and the Biopsychosocial Contributions of Children's Vagal Flexibility and Mothers' Compassion.

Individual differences in children’s prosocial behaviors, including their willingness to give up something of value for the benefit of others, are rooted in physiological and environmental processes. In a sample of 4-year-old children, we previously found evidence that flexible changes in respiratory sinus arrhythmia (RSA) were linked to donation behavior, and that these physiological patterns may support greater sensitivity to the positive effects of compassionate parenting on donation behavior. The current study focused on a follow-up assessment of these children at age 6. First, we examined the stability of individual differences in donation behavior and related parasympathetic nervous system (PNS) activity from age 4 to 6. Second, we examined associations between donation behavior and RSA at 6 years. Third, we examined whether the association between children’s RSA and donation behavior at age 6 varied depending on mothers’ compassionate love. We found low to modest stability in donation behavior and RSA reactivity from age 4 to 6. These findings provide preliminary evidence that stable individual differences in altruism, as reflected by generosity, and in some aspects of parasympathetic functioning during opportunities to be prosocial, emerge in childhood. In addition, we found that some of the same associations between donation behavior, RSA, and compassionate love that we previously observed in children at 4 years of age continued to be evident 2 years later at age 6. Greater decreases in RSA when given the opportunity to donate were associated with children donating more of their own resources which, in turn, were associated with greater RSA recovery after the task. Lastly, mothers’ compassionate love was positively associated with donation behavior in children who demonstrated stronger decreases in RSA during the task; compassionate parenting and RSA reactivity may serve as external and internal supports for prosociality that build on each other. Taken together, these findings contribute to the perspectives that individual differences in altruistic behaviors are intrinsically linked to healthy vagal flexibility, and that biopsychosocial approaches provide a useful framework for examining and understanding the environmental and physiological processes underlying these individual differences.

Vagal Flexibility during Exercise: Impact of Training, Stress, Anthropometric Measures, and Gender.

We evaluated the effect of physical training, stress, anthropometric measures, and gender upon the reactivity and recovery of the heart rate variability (HRV) during a cardiorespiratory test. Professors (N = 54) were evaluated using the following: physical training: time, frequency, and length of physical exercise; resting heart rate (HR); maximum HR; and recovery HR; stress: stress symptoms, work stress, vital events, and perceived stress; anthropometric measures: body mass index, waist circumference (WC), waist-hip ratio (WHR), and fat percentage (FP); and HRV before, during, and after the test. The HRV decreased during and increased after the test. Increased recovery HR was associated with the decreased vagal output during the test, and decreased recovery HR was associated with the increased posttest vagal input. The higher the work control and stress symptoms of men and the higher the perceived stress for both genders, the lower the vagal output during the test. The lower stress symptom and work control of men and the lower work demand of women were associated with the posttest vagal increase. The increased WC and decreased WHR of men were associated with the lower vagal output during the test and the lower posttest vagal increase. The lower FP also was associated with the greater recovery.

Vagal Flexibility Mediates the Association Between Resting Vagal Activity and Cognitive Performance Stability Across Varying Socioemotional Demands.

Vagal flexibility describes the ability to modulate cardiac vagal responses to fit a dynamic range of challenges. Extant theory on vagal function implies that vagal flexibility is a mediating mechanism through which resting vagal activity, a putative individual difference related to self-regulation, affects adaptive behavior and cognition. Nevertheless, little research has directly tested this hypothesis, thereby leaving fundamental mechanisms of vagal function and adaptability unclear. To this end, 47 healthy subjects completed a 5 min baseline followed by Stroop tasks combined with concurrent auditory distractors. There were four different Stroop task conditions that varied the social and emotional content of the auditory distractors. Electrocardiogram was continuously recorded to assess vagal responses to each condition as heart rate variability [root mean square of successive differences (RMSSDs)] reactivity. Vagal flexibility significantly mediated the association between resting vagal activity and stability of inhibition performance (Stroop interference) scores. In particular, higher resting RMSSD was related to higher standard deviation of RMSSD reactivity scores, reflecting greater differences in RMSSD reactivity between distractor conditions (i.e., greater vagal flexibility). Greater vagal flexibility was in turn related to more stability in Stroop interference across the same conditions. The mean of RMSSD reactivity scores across conditions was not significantly related to resting RMSSD or stability in Stroop performance, and mean RMSSD reactivity did not mediate relations between resting RMSSD and stability in Stroop performance. Overall, findings suggest that vagal flexibility may promote the effects of resting vagal activity on stabilizing cognitive inhibition in the face of environmental perturbations.

The impact of emotion regulation on cardiovascular, neuroendocrine and psychological stress responses

Emotion regulation (ER) is vital for healthy adaptation and influences how individuals respond to and recover from stress. We investigated whether ER improves cardiovascular, neuroendocrine and psychological stress responses, while taking into account the moderating role of habitual ER tendencies. Eighty-six women applied either cognitive reappraisal or expressive suppression (vs. control) while undergoing a stressor. Reappraisal decreased heart rate variability (HRV) during stress, but also initiated a stronger post-stress HRV-recovery relative to suppression. This reappraisal-induced cardiac-vagal-flexibility was particularly observed in habitual reappraisers. Furthermore, the reappraisal group reported enhanced positive affect, whereas the suppression group experienced more unpleasantness and expressed higher cortisol levels than controls. Heightened cortisol reactivity was also found in the reappraisal group, but only for individuals scoring low or mean on trait reappraisal. These results provide preliminary evidence that reappraisal fosters psychophysiological adaptation in response to stress, but also suggest that ER-strategy-efficacy critically depends on its habitual use.

The Physiological Regulation of Emotion During Social Interactions: Vagal Flexibility Moderates the Effects of a Military Parenting Intervention on Father Involvement in a Randomized Trial.

To make prevention programs more effective and understand "what works for whom," evidence regarding what individual characteristics predict intervention responsiveness is needed. Previous studies have evaluated a military parent training program known as After Deployment Adaptive Parenting Tools/ADAPT, yet less is understood about the program's varying effects for fathers. We tested the physiological regulation of emotion during social interactions as a moderator predicting fathers' responsiveness in a randomized trial of ADAPT, in which emotion regulation was operationally measured through vagal flexibility (VF; dynamic changes in cardiac vagal tone). Families with a child aged between 4 and 13years for whom physiological data were gathered (n = 145) were randomly assigned to ADAPT (14-week face-to-face group intervention) or a control group (services as usual). Fathers in these families were National Guard/Reserve members who had been deployed to war in Iraq and/or Afghanistan and recently returned. Prior to the intervention, cardiac data was collected in-home throughout a set of family interaction tasks and VF was operationalized as the changes in high frequency (HF) power of heart rate variability (HRV) from a reading task to a problem-solving task. Parenting behaviors were observed and coded based on theory-driven indicators pre-intervention and at 1-year follow-up. Results of structural equation modeling showed that VF significantly moderated fathers' intervention responsiveness, such that fathers with higher vs. lower VF exhibited more effective parenting at 1-year follow-up if they were randomized into ADAPT vs. the control group. This study is the first to demonstrate that parasympathetic vagal functioning may be a biomarker to predict response to a military parenting intervention to enhance parenting in combat deployed fathers. The implications for precision-based prevention are discussed.

Sharing the filmic experience - The physiology of socio-emotional processes in the cinema.

As we identify with characters on screen, we simulate their emotions and thoughts. This is accompanied by physiological changes such as galvanic skin response (GSR), an indicator for emotional arousal, and respiratory sinus arrhythmia (RSA), referring to vagal activity. We investigated whether the presence of a cinema audience affects these psychophysiological processes. The study was conducted in a real cinema in Berlin. Participants came twice to watch previously rated emotional film scenes eliciting amusement, anger, tenderness or fear. Once they watched the scenes alone, once in a group. We tested whether the vagal modulation in response to the mere presence of others influences explicit (reported) and implicit markers (RSA, heart rate (HR) and GSR) of emotional processes in function of solitary or collective enjoyment of movie scenes. On the physiological level, we found a mediating effect of vagal flexibility to the mere presence of others. Individuals showing a high baseline difference (alone vs. social) prior to the presentation of film, maintained higher RSA in the alone compared to the social condition. The opposite pattern emerged for low baseline difference individuals. Emotional arousal as reflected in GSR was significantly more pronounced during scenes eliciting anger independent of the social condition. On the behavioural level, we found evidence for emotion-specific effects on reported empathy, emotional intensity and Theory of Mind. Furthermore, people who decrease their RSA in response to others’ company are those who felt themselves more empathically engaged with the characters. Our data speaks in favour of a specific role of vagal regulation in response to the mere presence of others in terms of explicit empathic engagement with characters during shared filmic experience.

Cardiac vagal flexibility and accurate personality impressions: Examining a physiological correlate of the good judge.

Research has long sought to identify which individuals are best at accurately perceiving others' personalities or are good judges, yet consistent predictors of this ability have been difficult to find. In the current studies, we revisit this question by examining a novel physiological correlate of social sensitivity, cardiac vagal flexibility, which reflects dynamic modulation of cardiac vagal control. We examined whether greater cardiac vagal flexibility was associated with forming more accurate personality impressions, defined as viewing targets more in line with their distinctive self-reported profile of traits, in two studies, including a thin-slice video perceptions study (N = 109) and a dyadic interaction study (N = 175). Across studies, we found that individuals higher in vagal flexibility formed significantly more accurate first impressions of others' more observable personality traits (e.g., extraversion, creativity, warmth). These associations held while including a range of relevant covariates, including cardiac vagal tone, sympathetic activation, and gender. In sum, social sensitivity as indexed by cardiac vagal flexibility is linked to forming more accurate impressions of others' observable traits, shedding light on a characteristic that may help to identify the elusive good judge and providing insight into its neurobiological underpinnings.

Associations between childhood adversity and daily suppression and avoidance in response to stress in adulthood: can neurobiological sensitivity help explain this relationship?

ABSTRACTBackground and objectives: Although it has been postulated that psychological responses to stress in adulthood are grounded in childhood experiences in the family environment, evidence has been inconsistent. This study tested whether two putative measures of neurobiological sensitivity (vagal flexibility and attentional capacity) moderated the relation between women’s reported exposure to a risky childhood environment and current engagement in suppressive or avoidant coping in response to daily stress.Design and methods: Adult women (N = 158) recruited for a study of stress, coping, and aging reported on early adversity (EA) in their childhood family environment and completed a week-long daily diary in which they described their most stressful event of the day and indicated the degree to which they used suppression or avoidance in response to that event. In addition, women completed a visual tracking task during which heart rate variability and attentional capacity were assessed.Results: Multilevel mixed modeling analyses revealed that greater EA predicted greater suppression and avoidance only among women with higher attentional capacity. Similarly, greater EA predicted greater use of suppression, but only among women with greater vagal flexibility.Conclusion: Childhood adversity may predispose individuals with high neurobiological sensitivity to a lifetime of maladaptive coping.

Vagal flexibility: A physiological predictor of social sensitivity.

This research explores vagal flexibility--dynamic modulation of cardiac vagal control--as an individual-level physiological index of social sensitivity. In 4 studies, we test the hypothesis that individuals with greater cardiac vagal flexibility, operationalized as higher cardiac vagal tone at rest and greater cardiac vagal withdrawal (indexed by a decrease in respiratory sinus arrhythmia) during cognitive or attentional demand, perceive social-emotional information more accurately and show greater sensitivity to their social context. Study 1 sets the foundation for this investigation by establishing that vagal flexibility can be elicited consistently in the laboratory and reliably over time. Study 2 demonstrates that vagal flexibility has different associations with psychological characteristics than does vagal tone, and that these characteristics are primarily social in nature. Study 3 links individual differences in vagal flexibility with accurate detection of social and emotional cues depicted in still facial images. Study 4 demonstrates that individuals with greater vagal flexibility respond to dynamic social feedback in a more context-sensitive manner than do individuals with less vagal flexibility. Specifically, compared with their less flexible counterparts, individuals with greater vagal flexibility, when assigned to receive negative social feedback, report more shame, show more pronounced blood pressure responses, and display less sociable behavior, but when receiving positive social feedback display more sociable behavior. Taken together, these findings suggest that vagal flexibility is a useful individual difference physiological predictor of social sensitivity, which may have implications for clinical, developmental, and health psychologists.

Roots and Benefits of Costly Giving

Altruism, although costly, may promote well-being for people who give. Costly giving by adults has received considerable attention, but less is known about the possible benefits, as well as biological and environmental correlates, of altruism in early childhood. In the current study, we present evidence that children who forgo self-gain to help other people show greater vagal flexibility and higher subsequent vagal tone than children who do not, and children from less wealthy families behave more altruistically than those from wealthier families. These results suggest that (a) altruism should be viewed through a biopsychosocial lens, (b) the influence of privileged contexts on children’s willingness to make personal sacrifices for others emerges early, and (c) altruism and healthy vagal functioning may share reciprocal relations in childhood. When children help others at a cost to themselves, they could be playing an active role in promoting their own well-being as well as the well-being of others.