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

Abstract

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.

Parent–child physiological synchrony: Concurrent and lagged effects during dyadic laboratory interaction

“…This method would necessitate extremely precise second-by-second pairing of physiological and behavioral data (Gates & Liu, 2016). Future research may also explore associations between behavioral co-regulation and nonlinear indices of cardiac complexity, such as fractality and sample entropy (Berry, Palmer, Distefano, & Masten, 2019).…”

Within‐mother variability in vagal functioning and concurrent socioemotional dysregulation

“…For stressful tasks during which mothers typically exhibit sustained vagal withdrawal, detrimental effects of insufficient temporal variation in RSA may be more apparent. Further, the dynamics of cardiac time series during tasks that require active effortful regulation may be better captured by nonlinear indices of cardiac complexity, such as fractality and sample entropy (Berry et al., 2019). During tasks in which one must recruit and direct executive resources to master a challenge, internally organized temporal structure may indicate successful regulation, whereas a more loosely organized structure may indicate diminishing regulatory resources over time (e.g., giving up on the task; Berry et al., 2019).…”

“…Further, the dynamics of cardiac time series during tasks that require active effortful regulation may be better captured by nonlinear indices of cardiac complexity, such as fractality and sample entropy (Berry et al., 2019). During tasks in which one must recruit and direct executive resources to master a challenge, internally organized temporal structure may indicate successful regulation, whereas a more loosely organized structure may indicate diminishing regulatory resources over time (e.g., giving up on the task; Berry et al., 2019). Further, during stressful interactions, differences in types of maternal socioemotional dysregulation (e.g., overregulation versus underregulation) may become more pronounced, and there may be more complex relations between maternal vagal functioning and different types of dysregulation.…”

“…Whereas vagal withdrawal (evidenced by decreases in RSA) in response to acute stressors is a cost‐efficient strategy for mobilizing cardiometabolic resources, excessive withdrawal of the vagal brake during periods of relative quiescence may constitute an exaggerated, maladaptive physiological reaction (Porges, 2006). For optimal health, the temporal dynamics of the vagal system must be open to changing environmental inputs; nevertheless, a system whose organization is too chaotic or unpredictable may result in poor psychological and interpersonal functioning (Berry et al., 2019). For example, prior work has suggested that continuous cardiac arousal may be associated with problematic parenting (Lorber & O’Leary, 2005).…”

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

“…Current work is also examining other complex, non-linear measures thought to reflect flexible PNS responses, particularly across longer tasks with multiple data points. These include cardiac fractility, the optimal temporal variability of the heart rate variability series, and cardiac entropy, or the randomness of the series (Berry et al, 2019). More such research is needed to integrate and understand the complex nature of the physiology of emotion regulation.…”