Arousal, Gray's theory of anxiety, and the etiology of psychopathy

This paper focuses on Jeffrey Gray's theory of anxiety from the perspective of Fowles' (1980) application of his work to theories of arousal, psychophysiology, and the etiology of psychopathy. Although highly influential, the concept of general arousal failed to find support in terms of between-individuals assessment with multiple physiological measures. Gray's constructs of a behavioral inhibition system (BIS) that mediates anxiety, a behavioral approach or activation system (BAS) that energizes behavior to approach rewards, and a nonspecific arousal system that energizes behavior captured aspects of arousal. Fowles (1980) proposed that the BIS elicits electrodermal activity in response to threats, the BAS increases heart rate in response to reward incentive cues, and psychopathy is associated with a weak BIS. The paper reviews Gray's impact on future research on these topics, including early proposals relevant to the National Institute of Mental Health's Research Domain Criteria. Finally, the paper summarizes the evolution of theories of the etiology of psychopathy since 1980, noting ways in which aspects of Gray's theory are still seen in psychopathy research. Patrick's triarchic model has emerged as a major theory of psychopathy. Beauchaine's trait impulsivity theory of Attention Deficit Hyperactivity Disorder also is relevant.

Patterns of respiratory sinus arrhythmia and trajectories of anxiety and depressive symptoms in early adolescence

In children and adults, individual differences in patterns of respiratory sinus arrhythmia (RSA; i.e., interactions between resting RSA and RSA reactivity to stress) have emerged as a central predictor of internalizing symptoms. However, it is unclear whether individual differences in patterns of RSA also contribute to internalizing symptoms during the key developmental period of early adolescence, when rates of internalizing symptoms sharply increase. In the present multi-wave longitudinal study, we assessed whether patterns of RSA predicted trajectories of the two most common types of internalizing symptoms among adolescents: anxiety and depression. In the baseline session, we assessed RSA at rest and in response to a psychosocial stressor (Trier Social Stress Test [TSST]) in a sample of 75 early adolescents (Mage = 12.85). Youth then completed measures of anxiety and depressive symptoms at baseline and four times over approximately two years. Findings indicate that RSA patterns predicted trajectories of anxiety, but not depression. Specifically, region of significance analyses indicated that individuals with high resting RSA who demonstrated RSA augmentation to the lab stressor evinced decreasing anxiety over the follow-up period. In direct contrast, adolescents with high resting RSA in combination with RSA withdrawal to the stressor exhibited a trajectory of increasing anxiety. Findings provide preliminary evidence for understanding RSA as a developmentally salient risk or protective factor.

An Individualized, Data-Driven Biological Approach to Attention-Deficit/Hyperactivity Disorder (ADHD) Heterogeneity

Attention-deficit/hyperactivity disorder (ADHD) is the most commonly diagnosed mental health disorder in childhood, however, there is well-established heterogeneity in both the presentation of ADHD symptoms and secondary characteristics across the literature. Existing Diagnostic and Statistical Manual of Mental Disorders (DSM-5) nosology has been ineffective in explaining such heterogeneity in terms of both pathophysiology and clinical trajectories. The current study investigated ADHD heterogeneity via a biologically-based, data-driven approach (k-Means algorithm). Specifically, unique biological profiles (derived from patterns of parasympathetic and sympathetic functioning) were identified and utilized as predictors of clinical presentations. Two hundred eighty-nine participants (167 youth with ADHD), ages 5 to 13 years, completed an emotion-based task while indexes of parasympathetic (i.e., respiratory sinus arrhythmia [RSA]) and sympathetic (i.e., electrodermal activity [EDA]) activity were obtained. Overall, results suggest that three distinct biological profiles among youth with ADHD are evident, with biological profiles differing in regulation and arousal levels during emotionally evocative contexts: (Profile 1) underregulated, hyperaroused (negative contexts only), (Profile 2) typically regulated, underaroused, and (Profile 3) overregulated (positive contexts only), hyperaroused. Results are supported by several dopaminergic- and reward-based theories, integrating differing concepts across the literature, and adds biological support for existing models. Behaviorally, results may translate into differing clinical presentations, however, further work is needed. In general, youth with ADHD are heterogenous in autonomic functioning, which could have implications for synthesizing across differing theories within the literature, predicting clinical presentations, and developing targeted treatments.

Relations between lab indices of emotion dysregulation and negative affect reactivity in daily life in two independent studies

BACKGROUND

We investigated the extent to which physiological/biological measures of emotion dysregulation collected in the lab, resting respiratory sinus arrhythmia (RSA) in Study 1 and amygdala activation in response to negative stimuli in Study 2, combined with daily measures of interpersonal stressors predicted negative emotional states in outpatients better than the stressors alone.

METHODS

Participants were adult outpatients with emotional distress disorders (N=30 individuals in Study 1, and N=26 women in Study 2). After completing a laboratory session that collected physiological/biological measures of emotion dysregulation, participants then completed 1-3 weeks of ambulatory assessment during which they reported on interpersonal stressors and negative affective states several times per day.

RESULTS

Laboratory measures of emotion dysregulation were largely unrelated to either momentary or mean levels of daily-life hostility, sadness, and fear in both studies. However, resting RSA significantly moderated the association between day-level interpersonal stressors and momentary fear such that low resting RSA strengthened this association. Similarly, amygdala activation tended to moderate this relationship in the predicted direction.

LIMITATIONS

Both samples were relatively small and focused on only a limited set of diagnoses associated with emotion dysregulation. Only two possible physiological/biological markers of emotion dysregulation were examined.

CONCLUSIONS

The current studies support the collection of physiological/biological data on emotion dysregulation when indexing daily-life emotion dysregulation as the degree of emotional reactivity to stressors in daily life among outpatients with emotional distress disorders.

Emotion Regulation via the Autonomic Nervous System in Children with Attention-Deficit/Hyperactivity Disorder (ADHD): Replication and Extension

Attention-deficit/hyperactivity disorder (ADHD) is a prevalent disorder characterized by symptoms of inattention, hyperactivity, and/or impulsivity, as well as executive dysfunction. Recent work underlines the importance in understanding the role of emotion reactivity and regulatory deficits in the context of the disorder. One study (i.e., Musser et al. 2011) utilized a positive and negative emotion induction and suppression task, as well as indexes of autonomic nervous system reactivity, to examine emotional functioning in youth with ADHD. This study revealed inflexible parasympathetic-based regulation across emotion conditions among youth with ADHD compared to typically developing youth. The present study sought to replicate and extend these findings to a clinically recruited, diverse sample, while also examining sympathetic functioning. Two hundred fifty-nine participants (160 youth with ADHD), aged 5 to 13, completed the task utilized in Musser et al. 2011, while indexes of parasympathetic (i.e., respiratory sinus arrhythmia [RSA]) and sympathetic (i.e., pre-ejection period [PEP] and electrodermal activity [EDA]) reactivity were obtained. ADHD was associated with significantly elevated parasympathetic (i.e., augmented RSA) and sympathetic (as indexed by EDA) reactivity. Overall, results replicate and extend Musser et al. 2011, revealing sympathetic-linked disruptions in emotion reactivity and parasympathetic-linked disruptions in emotion regulation among youth with ADHD. Future studies of behavioral therapies for ADHD should consider the efficacy of adding an emotion regulation skills training component.

Parasympathetic Regulation and Inhibitory Control Predict the Development of Externalizing Problems in Early Childhood

The current report examined the longitudinal relations between cognitive self-regulation, physiological self-regulation, and externalizing problems. At age 4 (n = 98; 49 girls) and 6 (n = 87; 42 girls), children completed the Day-Night task, which taps the inhibitory control dimension of executive function. During the task, cardiac activity was measured and respiratory sinus arrhythmia (RSA) was derived as an index of parasympathetic activity. Mothers reported on externalizing problems. A cross-lagged path model was used to estimate longitudinal predictions while controlling for stability in all constructs over time. Earlier inhibitory control negatively predicted later externalizing problems, but not vice versa. However, RSA reactivity moderated this link; better inhibitory control predicted fewer externalizing problems only when reactivity to the Day-Night task ranged from mild RSA suppression to RSA augmentation. Externalizing problems at 6 years were highest among preschoolers who augmented RSA but showed poor inhibitory control performance, suggesting that risk for psychopathology may be better delineated by viewing self-regulation from an integrated, multi-system perspective.

Adolescent's respiratory sinus arrhythmia is associated with smoking rate five years later

INTRODUCTION

Vulnerability factors like respiratory sinus arrhythmia (RSA) may help identify adolescents at risk for nicotine dependence. We examined if resting RSA and the acute effects of smoking on RSA was associated with cigarette smoking five years later among adolescents at high risk for smoking escalation and nicotine dependence.

METHODS

Sixty-nine adolescents participated in a baseline laboratory session- RSA was collected before and after smoking a single cigarette ad libitum. Participants were then followed for five years.

RESULTS

Lower pre-smoke resting RSA was related to higher past month smoking rate five years later, even after controlling for baseline smoking rate and other relevant covariates including gender, race/ethnicity, age of initiated use, and frequency of exercise at baseline (p=0.018). Exploratory analyses suggested resting RSA is an independent predictor of increased cigarette rate beyond other baseline predictors.

CONCLUSIONS

Low resting RSA may be a vulnerability factor, helping to identify adolescents at risk for cigarette escalation.

Smoking's effects on respiratory sinus arrhythmia in adolescent smokers

Respiratory sinus arrhythmia (RSA) has emerged as an indicator of how well the body maintains homeostasis and flexibly responds to environmental demands. Previous research has shown that smoking has both acute and chronic effects on RSA in adults. More recent work has focused on adolescent smokers because the natural decrease in RSA over the lifespan might be hastened by smoking at an early age. The goal of the current study, then, was to examine the acute effects of smoking on RSA and mean heart rate (HR) in a group of adolescent smokers. Participants completed two experimental sessions separated by 6-10 weeks, during which resting electrocardiogram (EKG) data were collected before and after smoking or not smoking a single cigarette ad libitum. Results indicate that smoking significantly decreased resting RSA and increased mean HR. In addition, those who smoked their first cigarette earlier in life (i.e., before age 8 or 10) evidenced a greater decrease in RSA during their smoking session relative to those who tried smoking after age 10. Importantly, these findings are largely consistent with the adult literature and suggest that smoking has acute effects on both RSA and HR in adolescence.

Acoustic features of prairie vole (Microtus ochrogaster) ultrasonic vocalizations covary with heart rate

Vocalizations serve as a conspecific social communication system among mammals. Modulation of acoustic features embedded within vocalizations is used by several mammalian species to signal whether it is safe or dangerous to approach conspecific and heterospecific mammals. As described by the Polyvagal Theory, the phylogenetic shift in the evolution of mammals involved an adaptive neuroanatomical link between the neural circuits regulating heart rate and the muscles involved in modulating the acoustic features of vocalizations. However, few studies have investigated the covariation between heart rate and the acoustic features of vocalizations. In the current study, we document that specific features of vocalizations covary with heart rate in a highly social and vocal mammal, the prairie vole (Microtus ochrogaster). Findings with the prairie vole illustrate that higher pitch (i.e., fundamental frequency) and less variability in acoustic features of vocalizations (i.e., less vocal prosody) are associated with elevated heart rate. The study provides the first documentation that the acoustic features of prairie vole vocalizations may function as a surrogate index of heart rate.

Emotion dysregulation and dyadic conflict in depressed and typical adolescents: evaluating concordance across psychophysiological and observational measures

Many depressed adolescents experience difficulty in regulating their emotions. These emotion regulation difficulties appear to emerge in part from socialization processes within families and then generalize to other contexts. However, emotion dysregulation is typically assessed within the individual, rather than in the social relationships that shape and maintain dysregulation. In this study, we evaluated concordance of physiological and observational measures of emotion dysregulation during interpersonal conflict, using a multilevel actor-partner interdependence model (APIM). Participants were 75 mother-daughter dyads, including 50 depressed adolescents with or without a history of self-injury, and 25 typically developing controls. Behavior dysregulation was operationalized as observed aversiveness during a conflict discussion, and physiological dysregulation was indexed by respiratory sinus arrhythmia (RSA). Results revealed different patterns of concordance for control versus depressed participants. Controls evidenced a concordant partner (between-person) effect, and showed increased physiological regulation during minutes when their partner was more aversive. In contrast, clinical dyad members displayed a concordant actor (within-person) effect, becoming simultaneously physiologically and behaviorally dysregulated. Results inform current understanding of emotion dysregulation across multiple levels of analysis.