Feasibility of an Online Acute Stressor in Preschool Children of Mothers with Depression.

Maternal depression is a risk factor for future mental health problems in offspring, with stress-system function as a candidate vulnerability factor. Here we present initial validation of an online matching-task (MT) paradigm in young children exposed to maternal depression (N = 40), a first in stressor-paradigm research for this age group. Investigations of stress-system reactivity that can be conducted online are an innovative assessment approach, accelerated by the COVID-19 pandemic. Results indicate high feasibility, with a >75% data collection success rate across measures, similar-to or better-than in-person success rates in young children. Overall, the online MT elicited significant heart rate but not cortisol reactivity. Individual differences in child mental health symptoms were a moderator of reactivity to the stressor such that children with lower, but not higher, behavioral problems exhibited the typical pattern of cortisol reactivity to the online MT. Results are aligned with allostatic load models, which suggest downregulation of stress-system reactivity as a result of experiencing adversity and mental health vulnerability. Consistent with in-person research, this suggests that an early phenotype for the emergence of behavior problems may be linked to altered stress-system reactivity. Results hold potential clinical implications for intervention development and the future of online stress-system research. Trial Registration: Clinical Trial Registration: NCT04639557; (Building Regulation in Dual Generations-Telehealth Model [BRIDGE]).

Smartphone Photoplethysmography Pulse Rate Covaries With Stress and Anxiety During a Digital Acute Social Stressor.

OBJECTIVE: Heart rate is a transdiagnostic correlate of affective states and the stress diathesis model of health. Although most psychophysiological research has been conducted in laboratory environments, recent technological advances have provided the opportunity to index pulse rate dynamics in real-world environments with commercially available mobile health and wearable photoplethysmography (PPG) sensors that allow for improved ecologically validity of psychophysiological research. Unfortunately, adoption of wearable devices is unevenly distributed across important demographic characteristics, including socioeconomic status, education, and age, making it difficult to collect pulse rate dynamics in diverse populations. Therefore, there is a need to democratize mobile health PPG research by harnessing more widely adopted smartphone-based PPG to both promote inclusivity and examine whether smartphone-based PPG can predict concurrent affective states. METHODS: In the current preregistered study with open data and code, we examined the covariation of smartphone-based PPG and self-reported stress and anxiety during an online variant of the Trier Social Stress Test, as well as prospective relationships between PPG and future perceptions of stress and anxiety in a sample of 102 university students. RESULTS: Smartphone-based PPG significantly covaries with self-reported stress and anxiety during acute digital social stressors. PPG pulse rate was significantly associated with concurrent self-reported stress and anxiety ( b = 0.44, p = .018) as well as prospective stress and anxiety at the subsequent time points, although the strength of this association diminished the farther away pulse rate got from self-reported stress and anxiety (lag 1 model: b = 0.42, p = .024; lag 2 model: b = 0.38, p = .044). CONCLUSIONS: These findings indicate that PPG provides a proximal measure of the physiological correlates of stress and anxiety. Smartphone-based PPG can be used as an inclusive method for diverse populations to index pulse rate in remote digital study designs.

Induction of acute stress through an internet-delivered Trier Social Stress Test as assessed by photoplethysmography on a smartphone.

Recent studies have demonstrated the feasibility of administering the Trier Social Stress Test (TSST) through the internet, with major implications for promoting inclusivity in research participation. However, online TSST studies to date are limited by a lack of control groups and the need for biological measures of stress reactivity that can be fully implemented online. Here, we test smartphone-based photoplethysmography as a measure of heart rate reactivity to an online variant of the TSST. Results demonstrate significant acceleration in heart rate and heightened self-reported stress and anxiety in the TSST condition relative to a placebo version of the TSST. The placebo condition led to a significant increase in self-reported stress and anxiety relative to baseline levels, but this increase was smaller in magnitude than that observed in the TSST condition. These findings highlight the potential for smartphone-based photoplethysmography in internet-delivered studies of cardiac reactivity and demonstrate that it is critical to utilize random assignment to a control or stressor condition when administering acute stress online.

Alpha electroencephalogram (EEG) asymmetry among toddlers in foster care.

The majority of children living in foster care in the United States have a history of maltreatment and/or disrupted caregiving. Maltreatment in early childhood adversely affects development at many levels, including neurobiology and behavior. One neurobiological measure associated with maltreatment is alpha electroencephalogram (EEG) asymmetry. Prior research has found greater right frontal asymmetry among children with a history of maltreatment. However, little research has been extended developmentally downward to examine alpha asymmetry and its behavioral correlates among toddlers in foster care; this was the purpose of the present study. Differences in EEG asymmetry were examined between a sample of foster toddlers (mean age = 3.21 years, n = 38) and a community comparison, low-income sample without a history of foster care (mean age = 3.04 years, n = 16). The toddlers in the foster care group exhibited greater right alpha asymmetry, primarily driven by differences in parietal asymmetry. Neither frontal nor parietal asymmetry were clearly related to internalizing or externalizing behaviors, measured concurrently or at previous time points. These findings reveal differences in alpha EEG asymmetry among toddlers in foster care, and highlight the need to better understand associations between neurobiological and behavioral functioning following early adversity.

Acute stress impairs children's sustained attention with increased vulnerability for children of mothers reporting higher parenting stress.

Despite evidence that acute stress impairs attention in adults, there has been minimal research in children. Here, the effects of acute stress on Go/No-go performance were examined in young children (M age = 5.41 years). Given the critical role of the parent-child relationship to children's self-regulatory development, the extent to which parenting stress predicts children's cognitive vulnerability to acute stress and autonomic reactivity was also investigated. A between-groups design (n = 58 stress, n = 26 control) was used with oversampling of the stressor-exposed children to examine individual differences. The Parenting Stress Index and subscales were employed as a measure of parenting stress. Acute stress impaired children's sustained attention, but not inhibitory control. Higher parenting stress was associated with vulnerability to attentional impairment. Parenting distress was also positively associated with sympathetic reactivity to acute stress, but neither sympathetic nor parasympathetic reactivity was associated with attentional impairment. A conceptual model of pathways through which repetitive acute stress may contribute to self-regulatory difficulties is presented, including the potential buffering role of caregivers.

Recollections of positive early caregiving relate to sympathetic nervous system activation and chronic inflammation in subsequent generations.

To understand links between early experience and biomarkers of peripheral physiology in adulthood, this study examined associations between quality of early caregiving and markers of sympathetic activation and chronic inflammation in a sample of 52 low-income mothers and their preschool-aged children. Mothers reported on levels of positive caregiving experienced during childhood using the Structural Analysis of Social Behavior-Intrex. Mother and child sympathetic activation was indexed via pre-ejection period (PEP) at rest, during a dyadic social engagement task, and for children, while interacting with an unfamiliar adult. C-reactive protein (CRP) was collected using whole blood spots to assess levels of low-grade chronic inflammation. Results showed that mothers who reported experiencing more warm guidance and support for autonomy in early childhood displayed lower resting sympathetic nervous system activation (i.e., longer PEP) and lower chronic inflammation (i.e., CRP levels). Further, lower maternal chronic inflammation levels were associated with lower sympathetic activation (i.e., longer PEP) in their children at rest, and during social interactions with mother and a female stranger.

Cumulative risk exposure moderates the association between parasympathetic reactivity and inhibitory control in preschool-age children.

A child's cumulative risk for early exposure to stress has been linked to alterations of self-regulation outcomes, including neurobiological correlates of inhibitory control (IC). We examined whether children's ability to engage the parasympathetic nervous system impacts how risk affects IC. Children ages 3-5 years completed two laboratory measures of IC while respiratory sinus arrhythmia (RSA) was measured, indexing parasympathetic activity. Children with greater risk demonstrated lower IC; risk also moderated associations between RSA reactivity and IC. For children with less risk, greater RSA withdrawal during IC tasks was associated with better IC. In contrast, greater risk was associated with poor IC, regardless of RSA withdrawal. Effects of risk were more pronounced for cumulative than individual measures. Results suggest that cumulative risk exposure disrupts connectivity between physiological and behavioral components of self-regulation in early childhood. Parasympathetic withdrawal to cognitive tasks may be less relevant for performance in developmental samples experiencing greater life stress.

Intergenerational associations in executive function between mothers and children in the context of risk.

Executive functioning (EF) is critical for school readiness and other important life skills. Previous investigations have often neglected the important influence of parental EF skills in shaping their own children's EF. This study attempted to replicate recent empirical work that has shown that maternal EF is positively related to child EF. An ecological theoretical framework was used to examine the maternal EF-child EF link in family environments characterized by significant risk and socioeconomic adversity. Data from 38 mother-child dyads revealed that larger maternal working memory capacity was associated with greater child accuracy and slower reaction times on a child-friendly Go/No-Go task of response inhibition but not on an Emotional Go/No-Go task. This finding suggests that in contexts of risk and adversity, slower reaction times, instead of reflecting weaker EF skills, might reflect an adaptive skill-that is, exercising appropriate caution and careful responding on a challenging task. Results provide additional evidence of an intergenerational link between maternal EF and child EF and yield new insights into the nature of EF in adverse environments.

Early auditory evoked potential is modulated by selective attention and related to individual differences in visual working memory capacity.

A growing body of research suggests that the predictive power of working memory (WM) capacity for measures of intellectual aptitude is due to the ability to control attention and select relevant information. Crucially, attentional mechanisms implicated in controlling access to WM are assumed to be domain-general, yet reports of enhanced attentional abilities in individuals with larger WM capacities are primarily within the visual domain. Here, we directly test the link between WM capacity and early attentional gating across sensory domains, hypothesizing that measures of visual WM capacity should predict an individual's capacity to allocate auditory selective attention. To address this question, auditory ERPs were recorded in a linguistic dichotic listening task, and individual differences in ERP modulations by attention were correlated with estimates of WM capacity obtained in a separate visual change detection task. Auditory selective attention enhanced ERP amplitudes at an early latency (ca. 70-90 msec), with larger P1 components elicited by linguistic probes embedded in an attended narrative. Moreover, this effect was associated with greater individual estimates of visual WM capacity. These findings support the view that domain-general attentional control mechanisms underlie the wide variation of WM capacity across individuals.

Moral Injury Among Frontline Long-Term Care Staff and Management During the COVID-19 Pandemic.

Background: A growing body of research highlights the experiences of moral injury among healthcare professionals during the COVID-19 pandemic. Moral injury (i.e., participating in or witnessing acts that violate one's central moral values), is associated with a host of psychological sequelae and corresponding negative psychosocial impacts. There is a lack of research examining the experiences of moral injury among those working in long-term care settings during the COVID-19 pandemic. Given the drastic impact that the COVID-19 pandemic has had on long-term care facilities in Canada, it is important to understand the experiences of moral injury among those working in long-term care settings to inform the development of effective prevention and intervention strategies. Objectives & Method: The objectives of this study were to understand the experiences and impact of moral injury among Canadian frontline long-term care workers (staff and management) during the COVID-19 pandemic. Participants (N = 32 long-term care staff and management working in Ottawa and Manitoba) completed in-depth, semi-structured qualitative interviews and clinical diagnostic assessments (Mini International Neuropsychiatric Interviews; MINI; Version 7.0.2) between March 2021-June 2021. Findings: The core category of our qualitative grounded theory model of moral injury in long-term care exemplified four shared types of morally injurious experiences, paired with cognitive, affective, and physiological symptom domains. Seven associated main themes emerged, contributing to the experiences and impact of moral injury in long-term care: 1) Beliefs about older adults and long-term care; 2) Interpretation of morally injurious experiences; 3) Management of morally injurious experiences; 4) Long-term care pandemic impacts; 5) Personal pandemic impacts; 6) Structural impacts in long-term care; and 7) Mental health needs and supports. Clinical assessments demonstrated anxiety disorders (n = 4) and feeding and eating disorders (n = 3) were among the most frequently classified current psychiatric disorders among long-term care workers. Conclusions: This is the first Canadian study to examine the experiences and impact of moral injury in long-term care during the COVID-19 pandemic using qualitative and clinical diagnostic methodologies. Implications and insights for screening and intervention are offered.

Building Emotional Awareness and Mental Health (BEAM): study protocol for a phase III randomized controlled trial of the BEAM app-based program for mothers of children 18-36 months.

BACKGROUND: The prevalence of maternal depression and anxiety has increased during the COVID-19 pandemic, and pregnant individuals are experiencing concerningly elevated levels of mental health symptoms worldwide. Many individuals may now be at heightened risk of postpartum mental health disorders. There are significant concerns that a cohort of children may be at-risk for impaired self-regulation and mental illness due to elevated exposure to perinatal mental illness. With both an increased prevalence of depression and limited availability of services due to the pandemic, there is an urgent need for accessible eHealth interventions for mothers of young children. The aims of this trial are to evaluate the efficacy of the Building Emotion Awareness and Mental Health (BEAM) app-based program for reducing maternal depression symptoms (primary outcome) and improve anxiety symptoms, parenting stress, family relationships, and mother and child functioning (secondary outcomes) compared to treatment as usual (TAU). METHODS: A two-arm randomized controlled trial (RCT) with repeated measures will be used to evaluate the efficacy of the BEAM intervention compared to TAU among a sample of 140 mothers with children aged 18 to 36 months, who self-report moderate-to-severe symptoms of depression and/or anxiety. Individuals will be recruited online, and those randomized to the treatment group will participate in 10 weeks of psychoeducation modules, an online social support forum, and weekly group teletherapy sessions. Assessments will occur at 18-36 months postpartum (pre-test, T1), immediately after the last week of the BEAM intervention (post-test, T2), and at 3 months after the intervention (follow-up, T3). DISCUSSION: eHealth interventions have the potential to address elevated maternal mental health symptoms, parenting stress, and child functioning concerns during and after the COVID-19 pandemic and to provide accessible programming to mothers who are in need of support. This RCT will build on an open pilot trial of the BEAM program and provide further evaluation of this evidence-based intervention. Findings will increase our understanding of depression in mothers with young children and reveal the potential for long-term improvements in maternal and child health and family well-being. TRIAL REGISTRATION: ClinicalTrials.gov NCT05306626 . Registered on April 1, 2022.

Parasympathetic and sympathetic nervous systems interactively predict change in cognitive functioning in midlife adults.

The two branches of the autonomic nervous system (ANS) have been individually linked to changes in cognitive functioning: The parasympathetic nervous system (PNS) has been associated with healthy cognitive aging, whereas excessive sympathetic nervous system (SNS) activity has been linked to heightened cognitive decline. Despite these separate findings and despite the integrative nature of the ANS, little work has examined the two branches simultaneously to better understand their interactive effects on changes in cognitive functioning in midlife adults. We examined cognitive change in two waves of the Midlife in the United States (MIDUS) study cognitive project and indexed PNS and SNS activity from heart rate variability and epinephrine levels, respectively, from the MIDUS biomarker project (minimum n = 843, 57.9% female, mean age at first wave = 53.8 years). Our findings indicate that greater PNS responsivity (i.e., greater withdrawal and greater recovery) in response to cognitive challenge is associated with attenuated cognitive decline, but only among individuals with low SNS levels; at higher SNS levels, the effects of the PNS on cognitive decline are attenuated. These results suggest that future research targeting the ANS and cognitive aging should consider both ANS branch's effects simultaneously.

Study Protocol: The Coaching Alternative Parenting Strategies (CAPS) Study of Parent-Child Interaction Therapy in Child Welfare Families.

BACKGROUND: Child maltreatment (CM) constitutes a serious public health problem in the United States with parents implicated in a majority of physical abuse and neglect cases. Parent-Child Interaction Therapy (PCIT) is an intensive intervention for CM families that uses innovative "bug-in-ear" coaching to improve parenting and child outcomes, and reduce CM recidivism; however, the mechanisms underlying its effects are little understood. The Coaching Alternative Parenting Strategies (CAPS) study aims to clarify the behavioral, neural, and physiological mechanisms of action in PCIT that support positive changes in parenting, improve parent and child self-regulation and social perceptions, and reduce CM in child welfare-involved families. METHODS: The CAPS study includes 204 child welfare-involved parent-child dyads recruited from Oregon Department of Human Services to participate in a randomized controlled trial of PCIT versus a services-as-usual control condition (clinicaltrials.gov, NCT02684903). Children ages 3-8 years at study entry and their parents complete a pre-treatment assessment prior to randomization and a post-treatment assessment 9-12 months post study entry. Dyads randomized to PCIT complete an additional, abbreviated assessment at mid-treatment. Each assessment includes individual and joint measures of parents' and children's cardiac physiology at rest, during experimental tasks, and in recovery; observational coding of parent-child interactions; and individual electroencephalogram (EEG) sessions including attentional and cognitive control tasks. In addition, parents and children complete an emotion regulation task and parents report on their own and their child's adverse childhood experiences and socio-cognitive processes, while children complete a cognitive screen and a behavioral measure of inhibitory control. Parents and children also provide anthropometric measures of allostatic load and 4-5 whole blood spots to assess inflammation and immune markers. CM recidivism is assessed for all study families at 6-month follow-up. Post-treatment and follow-up assessments are currently underway. DISCUSSION: Knowledge gained from this study will clarify PCIT effects on neurobehavioral target mechanisms of change in predicting CM risk reduction, positive, responsive parenting, and children's outcomes. This knowledge can help to guide efforts to tailor and adapt PCIT to vary in dosage and cost on the basis of individual differences in CM-risk factors.

Gut Feelings Begin in Childhood: the Gut Metagenome Correlates with Early Environment, Caregiving, and Behavior.

Psychosocial environments impact normative behavioral development in children, increasing the risk of problem behaviors and psychiatric disorders across the life span. Converging evidence demonstrates that early normative development is affected by the gut microbiome, which itself can be altered by early psychosocial environments. However, much of our understanding of the gut microbiome's role in early development stems from nonhuman animal models and predominately focuses on the first years of life, during peri- and postnatal microbial colonization. As a first step to identify if these findings translate to humans and the extent to which these relationships are maintained after initial microbial colonization, we conducted a metagenomic investigation among a cross-sectional sample of early school-aged children with a range of adverse experiences and caregiver stressors and relationships. Our results indicate that the taxonomic and functional composition of the gut microbiome correlates with behavior during a critical period of child development. Furthermore, our analysis reveals that both socioeconomic risk exposure and child behaviors associate with the relative abundances of specific taxa (e.g., Bacteroides and Bifidobacterium species) as well as functional modules encoded in their genomes (e.g., monoamine metabolism) that have been linked to cognition and health. While we cannot infer causality within this study, these findings suggest that caregivers may moderate the gut microbiome's link to environment and behaviors beyond the first few years of life.IMPORTANCE Childhood is a formative period of behavioral and biological development that can be modified, for better or worse, by the psychosocial environment that is in part determined by caregivers. Not only do our own genes and the external environment influence such developmental trajectories, but the community of microbes living in, on, and around our bodies-the microbiome-plays an important role as well. By surveying the gut microbiomes of a cross-sectional cohort of early school-aged children with a range of psychosocial environments and subclinical mental health symptoms, we demonstrated that caregiving behaviors modified the child gut microbiome's association to socioeconomic risk and behavioral dysregulation.

Self-Compassion and Psycho-Physiological Recovery From Recalled Sport Failure.

Failure inherent to high-performance sport can precipitate emotional distress that can impair athletes' performance and physical and mental health. Identifying factors that allow athletes to manage failure to sustain their health is critical. Self-compassion, treating oneself kindly in response to failure, may help athletes manage failure; it buffers against negative affective psychological responses, yet athletes often fear self-compassion. It is unknown whether the benefits of self-compassion extend to athletes' physiological responses to failure and whether fear of self-compassion has an influence on psychological and physiological responses to failure, beyond self-compassion. The purpose of this study was to examine the influence of self-compassion on athletes' psychological and physiological responses when recalling a sport failure and determine if fear of self-compassion exerted unique effects, beyond self-compassion. Participants (n = 91; M age = 21) were university or national-level athletes. In this laboratory-based, observational study, athletes were connected to a multi-modal biofeedback system to measure physiological responding at baseline, during a stress induction (imagining a past performance failure), and during a recovery period. Physiological responding was assessed according to athletes' high-frequency heart rate variability (HRV), indexing parasympathetic nervous system activity, during the stress induction and recovery phase. Next, to assess psychological reactivity, athletes completed a series of scales (behavioral reactions, thoughts, and emotions). Regression analyses revealed that self-compassion predicted athletes' HRV reactivity to the stress induction (ß = 0.30, p < 0.05). There was no relationship between self-compassion and HRV recovery. Further, self-compassion predicted adaptive behavioral reactions (ß = 0.46, p < 0.01), and negatively predicted maladaptive thoughts (ß = -0.34, p < 0.01) and negative affect (ß = -0.39, p < 0.01). Fear of self-compassion explained additional variance in some maladaptive thoughts and behavioral reactions. Results suggest that self-compassion promotes adaptive physiological and psychological responses in athletes relative to a recalled sport failure and may have implications for performance enhancement, recovery and health outcomes. Further, addressing athletes' fears of self-compassion may also be important in promoting optimal psychological recovery.

Parasympathetic and sympathetic activity are associated with individual differences in neural indices of selective attention in adults.

Multiple theoretical frameworks posit that interactions between the autonomic nervous system and higher-order neural networks are crucial for cognitive and emotion regulation. However, few studies have directly examined the relationship between measures of autonomic physiology and brain activity during cognitive tasks, and fewer studies have examined both the parasympathetic and sympathetic autonomic branches when doing so. Here, 93 adults completed an ERP auditory selective attention task concurrently with measures of parasympathetic activity (high-frequency heart rate variability; HF-HRV) and sympathetic activity (preejection period; PEP). We focus on the well-studied N1 ERP component to test for associations with baseline values of HF-HRV and PEP. Individuals with higher resting HF-HRV and shorter resting PEP showed larger effects of selective attention on their ERPs. Follow-up regression models demonstrated that HF-HRV and PEP accounted for unique variance in selective attention effects on N1 mean amplitude. These results are consistent with the neurovisceral integration model, such that greater parasympathetic activity is a marker of increased selective attention, as well as other theoretical models that emphasize the role of heightened sympathetic activity in more efficient attention-related processing. The present findings highlight the importance of autonomic physiology in the study of individual differences in neurocognitive function and, given the foundational role of selective attention across cognitive domains, suggest that both parasympathetic and sympathetic activity may be key to understanding variability in brain function across a variety of cognitive tasks.

Effects of early adversity on neural mechanisms of distractor suppression are mediated by sympathetic nervous system activity in preschool-aged children.

Multiple theoretical frameworks posit that interactions between the autonomic nervous system and higher-order neural networks are crucial for cognitive regulation. However, few studies have simultaneously examined autonomic physiology and brain activity during cognitive tasks. Such research is promising for understanding how early adversity impacts neurocognitive development in children, given that stress experienced early in life impacts both autonomic function and regulatory behaviors. We recorded event-related potentials (ERPs) as a neural measure of auditory selective attention, and cardiovascular measures of high-frequency heart rate variability (HF-HRV) and preejection period (PEP), in 105 3-5-year-old children with varying degrees of socioeconomic risk. First, we replicated a previous study from our lab: Increased socioeconomic risk was associated with larger ERP amplitudes elicited by distracting sounds. Next, we tested whether PEP and HF-HRV (at rest and during the task) were associated with the distractor ERP response, and found that a physiological profile marked by heightened sympathetic nervous system activity, indexed by shorter PEP, was associated with better ERP suppression of distractor sounds in lower SES children. Finally, we found that PEP mediated the relationship between socioeconomic risk and larger ERP responses to distractor sounds. In line with similar reports, these results suggest that for lower SES children, there is a potential biological cost of achieving better cognitive performance, seen here as increased cardiovascular arousal both at rest and in response to task demands. (PsycINFO Database Record

Conceptual precision is key in acute stress research: A commentary on Shields, Sazma, & Yonelinas, 2016.

A recent meta-analytic review by Shields, Sazma, & Yonelinas (2016) brings to the fore several conceptual issues within the stress and executive function (EF) literatures. We present a critique of these issues, using the review as an exemplar of how stress and EF are often examined empirically. The review summarizes research suggesting that EF is not only trait-like, but can be also state-like, influenced by factors such as acute stress. It has numerous strengths including its scope in examining EF across domains, inclusion of moderators, and timeliness, given the rapidly expanding field of stress research. We argue that the conclusions would be less equivocal with a more precise and neurally-informed consideration of EF, stressor, and timing assessments. A detailed discussion of these issues is provided, using the inhibition EF domain as an example, in order to illustrate key limitations and potential consequences of broad inclusion criteria. We endeavor to promote precise, shared definitions in the service of delineating a more complete and consistent account of acute stress effects on EF.

Resting sympathetic arousal moderates the association between parasympathetic reactivity and working memory performance in adults reporting high levels of life stress.

The neurovisceral integration model stipulates that autonomic function plays a critical role in the regulation of higher-order cognitive processes, yet most work to date has examined parasympathetic function in isolation from sympathetic function. Furthermore, the majority of work has been conducted on normative samples, which typically demonstrate parasympathetic withdrawal to increase arousal needed to complete cognitive tasks. Little is known about how autonomic regulation supports cognitive function in populations exposed to high levels of stress, which is critical given that chronic stress exposure alters autonomic function. To address this, we sought to characterize how parasympathetic (high-frequency heart rate variability, HF-HRV) and sympathetic (preejection period, PEP) measures of cardiac function contribute to individual differences in working memory (WM) capacity in a sample of high-risk women. HF-HRV and PEP were measured at rest and during a visual change detection measure of WM. Multilevel modeling was used to examine within-person fluctuations in WM performance throughout the task concurrently with HF-HRV and PEP, as well as between-person differences as a function of resting HF-HRV and PEP levels. Results indicate that resting PEP moderated the association between HF-HRV reactivity and WM capacity. Increases in WM capacity across the task were associated with increases in parasympathetic activity, but only among individuals with longer resting PEP (lower sympathetic arousal). Follow-up analyses showed that shorter resting PEP was associated with greater cumulative risk exposure. These results support the autonomic space framework, in that the relationship between behavior and parasympathetic function appears dependent on resting sympathetic activation.

Validation of autonomic and endocrine reactivity to a laboratory stressor in young children.

The validation of laboratory paradigms that reliably induce a stress response [including hypothalamic-pituitary-adrenal (HPA) axis and autonomic nervous system (ANS) activation], is critical for understanding how children's stress-response systems support emotional and cognitive function. Early childhood research to date is markedly limited, given the difficulty in establishing paradigms that reliably induce a cortisol response. Furthermore, research to date has not included a control condition or examined concurrent ANS reactivity. We addressed these limitations by characterizing the extent to which a modified matching task stressor paradigm induces HPA and ANS activation, beyond a closely matched control condition. Modifications include an unfamiliar and unfriendly assessor to increase the stressful nature of the task. Results validate the matching task as a laboratory stressor, with significant differences in HPA and ANS responsivity between conditions. The Stressor group exhibited a cortisol increase post-stressor, while the Control group was stable over time. Children in both conditions exhibited reduced parasympathetic activity to the first-half of the task, but in the second-half, only children in the Stressor condition, who were experiencing exaggerated signals of failure, exhibited further parasympathetic decline. The Stressor condition induced higher sympathetic activity (versus Control) throughout the task, with exaggerated second-half differences. Within the Stressor condition, responsivity was convergent across systems, with greater cortisol reactivity correlated with the magnitude of parasympathetic withdrawal and sympathetic engagement. Future research employing the matching task will facilitate understanding the role of HPA and ANS function in development.