Assessing Children's Autonomic Nervous System Activity During Structured Tasks: A Feasibility and Reliability Study in Ghana.

The significance of physiological regulation in relation to behavioral and emotional regulation is well documented, but primarily in economically advantaged contexts. Few studies have been conducted in low- and middle-income countries. We investigated the feasibility and reliability of measuring autonomic nervous system (ANS) activity and behavior during challenge tasks in 30 children aged 8-10 years in Ghana during two visits, 1 week apart. Completeness of ANS data ranged from 80% to 100% across all tasks. There was low-to-moderate test-retest reliability of video mood induction (VMI) emotion ratings and balloon analog risk task (BART) pumps (r = 0.34-0.52). VMI elicited higher targeted emotion ratings in Visit 2 than Visit 1. Respiratory sinus arrhythmia (RSA) was higher, and pre-ejection period (PEP) was longer at Visit 2 than Visit 1 for baseline and both tasks. RSA was higher at baseline than during the VMI anger scene at Visit 1, whereas PEP was shorter at baseline than during all VMI emotion scenes at Visit 2. RSA was higher at baseline than during BART at both visits. In conclusion, ANS data collection within evocative and arousing challenge tasks was feasible in Ghana, and the tasks were generally reliable and effective in eliciting target emotions and risk-taking behavior in this sample.

Callous-unemotional traits and pre-ejection period in response to reward.

Callous-unemotional (CU) traits have important utility in distinguishing individuals exhibiting more severe and persistent antisocial behavior, and our understanding of reward processing and CU traits contributes to behavioral modification. However, research on CU traits often investigated reward alongside punishment and examined solely on average reward reactivity, neglecting the reward response pattern over time such as habituation. This study assessed individuals' pre-ejection period (PEP), a sympathetic nervous system cardiac-linked biomarker with specificity to reward, during a simple reward task to investigate the association between CU traits and both average reward reactivity and reward response pattern over time (captured as responding trajectory). A heterogeneous sample of 126 adult males was recruited from a major metropolitan area in the US. Participants reported their CU traits using the Inventory of Callous-Unemotional Traits and completed a simple reward task while impedance cardiography and electrocardiogram were recorded to derive PEP. The results revealed no significant association between average PEP reward reactivity and CU traits. However, CU traits predicted both linear and quadratic slopes of the PEP reactivity trajectory: individuals with higher CU traits had slower habituation initially, followed by a rapid habituation in later blocks. Findings highlight the importance of modeling the trajectory of PEP reward response when studying CU traits. We discussed the implications of individuals with high CU traits having the responding pattern of slower initial habituation followed by rapid habituation to reward and the possible mechanisms.

Depressive symptoms, task choice, and effort: The moderating effect of personal control on cardiac response.

Dysphoric individuals perceive mental tasks as more demanding and show increased cardiovascular responses during the performance of easy cognitive tasks. Recent research on action shielding indicates that providing individuals with personal control over their tasks can mitigate the effects of manipulated affective states on cardiovascular responses reflecting effort. We investigated whether the shielding effect of personal choice also applies to the effect of dispositional negative mood on effort. N = 125 university students with high (dysphoric) versus low (nondysphoric) depressive symptoms engaged in an easy cognitive task either by personal choice or external assignment. As expected, dysphoric individuals showed significantly stronger cardiac PEP reactivity during task performance when the task was externally assigned. Most importantly, this dysphoria effect disappeared when participants could ostensibly personally choose their task. Our findings show that the previously observed shielding effect of personal action choice against incidental affective stimulation also applies to dispositional negative affect.

Physiological synchrony in supportive discussions: An examination of co-rumination, relationship type, and heterogeneity.

During times of stress, we look to close others for support. Social support conversations are critical for relationship maintenance and well-being. Yet, certain ways of talking about problems-such as co-ruminating-can exacerbate stress. Since social support and co-rumination are both dyadic processes, it is important to examine physiological responses during these conversations in a dyadic manner. Little research has examined physiological synchrony of the sympathetic nervous system (SNS) during social support conversations or co-ruminative conversations. The current research capitalizes on an experimental manipulation of co-rumination using a sample of close friends (147 dyads) and romantic partners (113 dyads) to examine physiological covariation in the context of support. Across both samples, dyads exhibited significant physiological covariation in pre-ejection period reactivity (PEP). Contrary to our hypothesis, dyads in the co-rumination condition did not show more covariation. Close friend dyads did, however, exhibit more covariation as compared to romantic dyads. We also found significant variability in physiological covariation across dyads, with a minority of dyads exhibiting negative covariation of PEP reactivity. The homogeneity of the samples limits the generalizability of the findings and highlights the need for more diverse samples in future work. These findings underline the need for further exploration into the mechanisms that contribute to distinct patterns of physiological synchrony, the conditions in which negative synchrony occurs, and what predicts especially strong positive synchrony. This work extends our understanding of physiological synchrony of the sympathetic nervous system during support conversations and emphasizes the importance of considering heterogeneity in physiological processes.

Cognitive conflict does not always mean high effort: Task difficulty's moderating effect on cardiac response.

This article presents an experiment (N = 127 university students) testing whether the previously found impact of conflict primes on effort-related cardiac response is moderated by objective task difficulty. Recently, it has been shown that primed cognitive conflict increases cardiac pre-ejection period (PEP) reactivity-an index of effort intensity-during the performance of relatively easy tasks. This effect could be attributed to conflict-related negative affect. Consequently, as it has been shown for other types of negative affect, we expected conflict primes' effect to be task-context dependent and thus to be moderated by objective task difficulty. In a between-persons design, we manipulated conflict via embedded pictures of conflict-related vs. non-conflict-related Stroop items in a memory task. We expected primed conflict to increase effort in a relatively easy version of the task but to lead to disengagement when task difficulty was objectively high. PEP reactivity corroborated our predictions. Rather than always increasing effort, cognitive conflict's effect on resource mobilization was context-dependent and resulted in weak responses in a difficult task.

Unveiling gender differences in psychophysiological dynamics: support for a two-dimensional autonomic space approach.

Introduction: To date, studies focusing on the connection between psychological functioning and autonomic nervous system (ANS) activity usually adopted the one-dimensional model of autonomic balance, according to which activation of one branch of the ANS is accompanied by an inhibition of the other. However, the sympathetic and parasympathetic branches also activate independently; thus, co-activation and co-inhibition may occur, which is demonstrated by a two-dimensional model of ANS activity. Here, we apply such models to assess how markers of the autonomic space relate to several critical psychological constructs: emotional contagion (EC), general anxiety, and positive and negative affect (PA and NA). We also examined gender differences in those psychophysiological relations. Methods: In the present study, we analyzed data from 408 healthy students, who underwent a 5-min group baseline period as part of their participation in several experiments and completed self-reported questionnaires. Electrocardiogram (ECG), electrodermal activity (EDA), and respiration were recorded. Respiratory sinus arrhythmia (RSA), pre-ejection period (PEP), as well as cardiac autonomic balance (CAB) and regulation (CAR) and cross-system autonomic balance (CSAB) and regulation (CSAR), were calculated. Results: Notably, two-dimensional models were more suitable for predicting and describing most psychological constructs. Gender differences were found in psychological and physiological aspects as well as in psychophysiological relations. Women's EC scores were negatively correlated with sympathetic activity and positively linked to parasympathetic dominance. Men's PA and NA scores were positively associated with sympathetic activity. PA in men also had a positive link to an overall activation of the ANS, and a negative link to parasympathetic dominance. Discussion: The current results expand our understanding of the psychological aspects of the autonomic space model and psychophysiological associations. Gender differences and strengths and weaknesses of alternative physiological models are discussed.

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.

The power of personal control: Task choice attenuates the effect of implicit sadness on sympathetically mediated cardiac response.

Implicitly processed pictures of facial expressions of emotions have been found to systematically influence sympathetically mediated cardiovascular reactivity during task performance. According to the Implicit-Affect-Primes-Effort model, this happens because different affect primes activate the concepts of performance ease versus performance difficulty. Grounded in a recent action shielding model, our laboratory experiment (N = 129 university students) tested whether engaging in action by personal choice can immunize against those implicit affective influences on effort. Participants worked on an objectively difficult cognitive task, which was either externally assigned or ostensibly personally chosen. As predicted, participants in the assigned task condition showed weaker cardiac pre-ejection period reactivity during task performance, reflecting disengagement, when they were primed with sadness than when they were exposed to anger primes. Most relevant, this affect prime effect disappeared when participants could ostensibly choose their task themselves. These findings replicate previous research on implicit affect's impact on sympathetically mediated cardiac response and extend the literature on action shielding by personal choice effects to implicit affective influences on action execution.

Noise annoys-But personal choice can attenuate noise effects on cardiac response reflecting effort.

Since personal choice fosters commitment and shields action execution against potentially conflicting influences, two laboratory experiments with university students (N = 228) tested whether engaging in action by personal choice versus external assignment of task characteristics moderates the effect of irrelevant acoustic noise on cardiovascular responses reflecting effort. Participants who could personally choose the stimulus color of moderately difficult cognitive tasks were expected to be shielded against the irrelevant noise. By contrast, when the stimulus color was externally assigned, we predicted receptivity for the irrelevant noise to be high. As expected, in both experiments, participants in the assigned color condition showed stronger cardiac pre-ejection period reactivity during task performance when exposed to noise than when working in silence. On the contrary, participants who could choose the stimulus color were shielded against the noise effect on effort. These findings conceptually replicate and extend research on the action shielding effect by personal choice and hold practical implications for occupational health.

Personal task choice attenuates implicit happiness effects on effort: A study on cardiovascular response.

Research on the Implicit-Affect-Primes-Effort model (Gendolla, 2012) found that priming happiness or anger in challenging tasks results in stronger sympathetically mediated cardiovascular responses, reflecting effort, than priming sadness or fear. Recent studies on action shielding revealed that personal task choice can attenuate affective influences on action execution (e.g., Gendolla et al., 2021). The present experiment tested if this action shielding effect also applies to affect primes' influences on cardiovascular response. Participants (N = 136) worked on a cognitive task with integrated briefly flashed and backward masked facial expressions of sadness vs. happiness. Half of the participants could ostensibly choose whether they wanted to work on an attention or on a memory task, while the other half was assigned to one task. Our findings revealed effects on cardiac pre-ejection period (PEP), which align with the expected outcomes for a task of unfixed difficulty where participants establish their own performance standard. Most importantly, task choice shielded against the implicit affective influence on PEP that was evident when the task was externally assigned. Effects on systolic blood pressure (SBP) reactivity largely corresponded to those of PEP.

Cardiac psychophysiological tuning to socioaffective content is disrupted in aged rhesus monkeys (Macaca mulatta).

Aging ushers in numerous disruptions to autonomic nervous system (ANS) function. Although the effects of aging on ANS function at rest are well characterized, there is surprising variation in reports of age-related differences in ANS reactivity to psychosocial stressors, with some reports of decreases and other reports of increases in reactivity with age. The sources of variation in age-related differences are largely unknown. Nonhuman primate models of socioaffective aging may help to uncover sources of this variation as nonhuman primates share key features of human ANS structure and function and researchers have precise control over the environments in which they age. In this report, we assess how response patterns to dynamic socioaffective stimuli in the parasympathetic and sympathetic branches of rhesus monkeys (Macaca mulatta) ANS differ in aged compared to middle-aged monkeys. We find that respiratory sinus arrhythmia, a cardiac indicator of activity in the parasympathetic branch of the ANS, exhibits age-related disruptions in responding while monkeys view videos of conspecifics. This suggests that there are evolutionarily conserved mechanisms responsible for the patterns of affective aging observed in humans and that aged rhesus monkeys are a robust translational model for human affective aging.

Emotion dysregulation and reward responsiveness as predictors of autonomic reactivity to an infant cry task among substance-using pregnant and postpartum women.

Maternal substance use may interfere with optimal parenting, lowering maternal responsiveness during interactions with their children. Previous work has identified maternal autonomic nervous system (ANS) reactivity to parenting-relevant stressors as a promising indicator of real-world parenting behaviors. However, less is known about the extent to which individual differences in emotion dysregulation and reward processing, two mechanisms of substance use, relate to maternal ANS reactivity in substance-using populations. The current study examined associations among emotion dysregulation, reward responsiveness, and ANS reactivity to an infant cry task among 77 low-income and substance-using women who were either pregnant (n = 63) or postpartum (n = 14). Two indicators of ANS functioning were collected during a 9 min computerized infant cry task (Crybaby task): respiratory sinus arrhythmia (RSA) and pre-ejection period. Mothers also completed self-reported measures of emotion dysregulation and reward responsiveness. Analyses revealed that trait emotion regulation was associated with RSA reactivity to the Crybaby task, such that greater emotion dysregulation was associated with greater RSA reduction during the infant cry task than lower emotion dysregulation. Reward responsiveness was not significantly associated with either indicator of ANS reactivity to the task. Findings revealed distinct patterns of associations linking emotion dysregulation with ANS reactivity during a parenting-related computerized task, suggesting that emotion regulation may be a key intervention target for substance-using mothers.

Action-orientation shields against primed cognitive conflict effects on effort-related cardiac response.

This article presents a quasi-experiment (N = 79 university students) testing whether individual differences in action-state orientation moderate primed cognitive conflict's effects on sympathetically mediated cardiac response during task performance reflecting effort. Action control theory posits that action-oriented individuals are less receptive to distracting affective stimuli during goal pursuit than state-oriented individuals because action-orientation is related to higher volitional skills. Therefore, we expected that action-oriented individuals should be shielded against conflict primes' effect on effort-related responses in the cardiovascular system. By contrast, state-oriented individuals should be more sensitive to irrelevant negative affective stimulation and therefore mobilize higher resources under such conditions. Responses of the cardiac pre-ejection period (PEP) during a moderately difficult short-term memory task corroborated these predictions. The present findings provide the first evidence that individual differences in action-state orientation indeed moderate previously demonstrated cognitive conflict priming effects on effort-related cardiac response and extend recent findings on action shielding.

Can personal task choice shield against fear and anger prime effects on effort? A study on cardiac response.

This experiment tested whether personal task choice can shield against implicit affective influences on sympathetically mediated cardiovascular response, reflecting effort. Participants were N = 121 healthy university students who completed a moderately difficult memory task with integrated briefly flashed and masked fear vs. anger primes. Half of the participants believed they could choose between an attention and a memory task, while the other half was automatically assigned to the task. Replicating previous research, we expected an influence of the affect primes on effort when the task was externally assigned. By contrast, when participants were given a task choice, we predicted strong action shielding and thus a weak implicit affect effect on resource mobilization. As expected, participants in the assigned task condition showed stronger cardiac pre-ejection period reactivity when exposed to fear primes than when processing anger primes. Importantly, this affect prime effect disappeared when participants could ostensibly choose the task. These findings add to other recent evidence for action shielding by personal task choice and importantly extend this effect to implicit affective influences on cardiac reactivity during task performance.

The pre-ejection period is a highly stress dependent parameter of paramount importance for pulse-wave-velocity based applications.

Purpose: The pulse-wave-velocity, is used for indirect, cuff-less, continuous blood pressure estimation. It is commonly detected by measuring the time delay between a defined point in an ECG and the arrival of the peripheral pulse wave (e.g., oxygen saturation sensor). The period between electrical stimulation of the heart (ECG) and actual blood ejection from the heart is called the pre-ejection period (PEP). This study aims at characterizing the PEP under mental and physical stress with focus on its relations to other cardiovascular parameters such as heart rate and importance for blood pressure (BP) estimation. Methods: We measured the PEP in 71 young adults at rest, under mental (TSST) and physical stress (ergometer) via impedance-cardiography. Results: The PEP is highly dependent on mental and physical load. It is strongly correlated with indicators of sympathetic strain (p < 0.001). At rest (mean 104.5 ms), the PEP shows a high interindividual variability but small intraindividual variability. Mental stress decreases the PEP by 16% (mean 90.0 ms) while physical stress halves PEP (mean 53.9 ms). The PEP does correlate differently with heart rate under differing circumstances (rest: R 2 0.06, mental stress: R 2 0.29, physical stress: R 2 0.65). Subsequently, using PEP and heart rate enables the discrimination of rest, mental and physical strain with a positive predictive value of 93%. Conclusion: The PEP is a cardiovascular parameter with large interindividual variability at rest and subject-depended dynamic under load which is of great importance for ECG-based pulse-wave-velocity (PWV) determination. Considering its variability and large impact on the pulse arrival time, PEP is a crucial factor in PWV based BP estimation.

Racial differences in sympathetic nervous system indicators: Implications and challenges for research.

Growing evidence indicates the presence of racial differences in sympathetic nervous system (SNS) functioning, yet the nature of these differences is unclear and appears to vary across different indices of SNS activity. Moreover, racial differences among commonly used indices of SNS activity are under-investigated. This systematic review examines racial differences among widely used resting SNS indices, such as electrodermal activity (EDA), pre-ejection period (PEP), and salivary alpha-amylase (sAA). Our review reveals that Black participants have consistently been found to display lower resting EDA compared to White participants. The few studies that have investigated or reported racial differences in PEP and sAA yield mixed findings about whether racial differences exist. We discuss potential reasons for racial differences in SNS activity, such as index-specific factors, lab confounds, psychosocial environmental factors, and their interactions. We outline a framework characterizing possible contributors to racial differences in SNS functioning. Lastly, we highlight the implications of several definitional, analytic, and interpretive issues concerning the treatment of group differences in psychophysiological activity and provide future recommendations.

Association between PTSD and Impedance Cardiogram-based contractility metrics during trauma recall: A controlled twin study.

Post-traumatic stress disorder (PTSD) is an independent risk factor for incident heart failure, but the underlying cardiac mechanisms remained elusive. Impedance cardiography (ICG), especially when measured during stress, can help understand the underlying psychophysiological pathways linking PTSD with heart failure. We investigated the association between PTSD and ICG-based contractility metrics (pre-ejection period (PEP) and Heather index (HI)) using a controlled twin study design with a laboratory-based traumatic reminder stressor. PTSD status was assessed using structured clinical interviews. We acquired synchronized electrocardiograms and ICG data while playing personalized-trauma scripts. Using linear mixed-effects models, we examined twins as individuals and within PTSD-discordant pairs. We studied 137 male veterans (48 pairs, 41 unpaired singles) from Vietnam War Era with a mean (standard deviation) age of 68.5(2.5) years. HI during trauma stress was lower in the PTSD vs. non-PTSD individuals (7.2 vs. 9.3 [ohm/s2 ], p = .003). PEP reactivity (trauma minus neutral) was also more negative in PTSD vs. non-PTSD individuals (-7.4 vs. -2.0 [ms], p = .009). The HI and PEP associations with PTSD persisted for adjusted models during trauma and reactivity, respectively. For within-pair analysis of eight PTSD-discordant twin pairs (out of 48 pairs), PTSD was associated with lower HI in neutral, trauma, and reactivity, whereas no association was found between PTSD and PEP. PTSD was associated with reduced HI and PEP, especially with trauma recall stress. This combination of increased sympathetic activation and decreased cardiac contractility combined may be concerning for increased heart failure risk after recurrent trauma re-experiencing in PTSD.

Is cognitive conflict really effortful? Conflict priming and shielding effects on cardiac response.

Two experiments with N = 221 university students investigated the impact of primed cognitive conflict on effort assessed as cardiac response in tasks that were not conflict-related themselves. Manifest cognitive conflict in cognitive control tasks is confounded with objective response difficulty (e.g., in incongruent Stroop task trials). This makes conclusions about the effortfulness of cognitive conflict itself difficult. We bypassed this problem by administrating pictures of congruent versus incongruent Stroop task stimuli as conflict primes. As predicted, primed cognitive conflict increased cardiac pre-ejection period (PEP) responses in an easy attention task in Experiment 1. Accordingly, cognitive conflict itself is indeed effortful. This effect was replicated in an easy short-term memory task in Experiment 2. Moreover, as further predicted, the primed cognitive conflict effect on PEP reactivity disappeared when participants could personally choose task characteristics. This latter effect corresponds to other recent evidence showing that personal action choice shields against incidental affective influences on action execution and especially on effort-related cardiovascular response.

Individual differences in action-state orientation moderate task difficulty effects on effort-related cardiac response.

A quasi experiment (N = 100 university students) tested whether individual differences in action-state orientation moderate task difficulty effects on resource mobilization assessed as cardiovascular response. According to action control theory, action-oriented individuals have higher self-regulation capacities in demanding situations than state-oriented persons. Action-orientated individuals should also self-generate positive affect in face of obstacles. Therefore, drawing on Wright's (1998) ability extension of motivational intensity theory and research on affective influences on effort-related cardiovascular response, we expected that action-orientation should lead to stronger effort-related cardiovascular responses in a difficult task, while state-orientation should do so in an easy task. Reactivity of cardiac pre-ejection period (PEP) during performance on a short-term memory task corroborated this hypothesis. The present findings provide the first evidence of a link between action-state orientation and effort-related responses in the cardiovascular system.

Pain and gain: Monetary incentive moderates pain's impact on effort-related cardiac response.

Ample evidence suggests that pain leads to additional demand in cognitive functioning, presumably due to its negative affective component and its propensity to capture attention. To highlight the role of motivational incentive, two experiments tested the combined effect of pain and monetary incentive on effort-related cardiovascular response during cognitive performance. In both studies, healthy volunteers received individually adjusted painful or nonpainful thermal stimulations during a difficult cognitive task (4-back task in Experiment 1; short-term memory task in Experiment 2) and expected high (12 Swiss Francs in both experiments) or low monetary incentive (1 Swiss Franc in Experiment 1; 0.10 Swiss Francs in Experiment 2) for successful performance. Effort was primarily assessed as changes in cardiac pre-ejection period (PEP). We predicted pain to increase subjective task difficulty during cognitive performance. Moreover, according to motivational intensity theory, we expected this to increase effort only when high effort was justified by high monetary incentive. Correspondingly, pain should lead to low effort (disengagement) when monetary incentive was low. Effort in the nonpainful conditions was expected to fall in between these conditions. The results of both studies support our predictions. Our findings provide the first evidence for the moderating effect of monetary incentive on physical pain's impact on effort-related cardiovascular response. Accordingly, motivational incentives can counteract effort deficits associated with pain.