Oscillatory Coupling Between Neural and Cardiac Rhythms.

Oscillations serve a critical role in organizing biological systems. In the brain, oscillatory coupling is a fundamental mechanism of communication. The possibility that neural oscillations interact directly with slower physiological rhythms (e.g., heart rate, respiration) is largely unexplored and may have important implications for psychological functioning. Oscillations in heart rate, an aspect of heart rate variability (HRV), show remarkably robust associations with psychological health. Mather and Thayer proposed coupling between high-frequency HRV (HF-HRV) and neural oscillations as a mechanism that partially accounts for such relationships. We tested this hypothesis by measuring phase-amplitude coupling between HF-HRV and neural oscillations in 37 healthy adults at rest. Robust coupling was detected in all frequency bands. Granger causality analyses indicated stronger heart-to-brain than brain-to-heart effects in all frequency bands except gamma. These findings suggest that cardiac rhythms play a causal role in modulating neural oscillations, which may have important implications for mental health.

Heart rate and breathing effects on attention and memory (HeartBEAM): study protocol for a randomized controlled trial in older adults.

BACKGROUND: In healthy people, the "fight-or-flight" sympathetic system is counterbalanced by the "rest-and-digest" parasympathetic system. As we grow older, the parasympathetic system declines as the sympathetic system becomes hyperactive. In our prior heart rate variability biofeedback and emotion regulation (HRV-ER) clinical trial, we found that increasing parasympathetic activity through daily practice of slow-paced breathing significantly decreased plasma amyloid-ß (Aß) in healthy younger and older adults. In healthy adults, higher plasma Aß is associated with greater risk of Alzheimer's disease (AD). Our primary goal of this trial is to reproduce and extend our initial findings regarding effects of slow-paced breathing on Aß. Our secondary objectives are to examine the effects of daily slow-paced breathing on brain structure and the rate of learning. METHODS: Adults aged 50-70 have been randomized to practice one of two breathing protocols twice daily for 9 weeks: (1) "slow-paced breathing condition" involving daily cognitive training followed by slow-paced breathing designed to maximize heart rate oscillations or (2) "random-paced breathing condition" involving daily cognitive training followed by random-paced breathing to avoid increasing heart rate oscillations. The primary outcomes are plasma Aß40 and Aß42 levels and plasma Aß42/40 ratio. The secondary outcomes are brain perivascular space volume, hippocampal volume, and learning rates measured by cognitive training performance. Other pre-registered outcomes include plasma pTau-181/tTau ratio and urine Aß42. Recruitment began in January 2023. Interventions are ongoing and will be completed by the end of 2023. DISCUSSION: Our HRV-ER trial was groundbreaking in demonstrating that a behavioral intervention can reduce plasma Aß levels relative to a randomized control group. We aim to reproduce these findings while testing effects on brain clearance pathways and cognition. TRIAL REGISTRATION: ClinicalTrials.gov NCT05602220. Registered on January 12, 2023.

High heart rate variability buffers the effect of attachment insecurity on sleep quality.

OBJECTIVE: Sleep quality is an important health-protective factor. Psychosocial factors, including attachment orientation, may be valuable for understanding who is at risk of poor sleep quality and associated adverse health outcomes. High attachment anxiety is reliably associated with adverse health outcomes, while high attachment avoidance is associated with adverse health outcomes when co-occurring with poor self-regulatory capacity, indexed by heart rate variability (HRV). We examined the associations between attachment anxiety, attachment avoidance, HRV, and sleep quality. METHODS: Using longitudinal data from a sample of 171 older adults measured four times over one year (M = 66.18 years old; 67.83% women), we separated the between-person variance (which we call "trait") and within-person variance (which we call "state") for attachment anxiety, attachment avoidance, and HRV (via the root mean square of successive differences). Sleep quality was measured with the Pittsburgh Sleep Quality Index. RESULTS: Higher trait attachment anxiety was associated with poorer global sleep quality (B = 0.22, p = .005). Higher state attachment avoidance was associated with poorer sleep quality (B = -0.13, p = .01), except for those with higher trait HRV. Higher state attachment anxiety was associated with poorer sleep quality (B = -0.15, p = .002), except for those with higher or mean trait HRV. Higher trait attachment anxiety was associated with poorer sleep quality (B = -0.31, p = .02), except for those with higher trait HRV. CONCLUSIONS: High trait HRV mitigated the adverse effects of attachment insecurity on sleep quality. Our results suggest that people with high trait HRV had greater self-regulation capacity, which may be able them to enact emotion regulation strategies effectively.

Negative emotions enhance memory-guided attention in a visual search task by increasing frontoparietal, insular, and parahippocampal cortical activity.

Previous literature demonstrated that long-term memory representations guide spatial attention during visual search in real-world pictures. However, it is currently unknown whether memory-guided visual search is affected by the emotional content of the picture. During functional magnetic resonance imaging (fMRI), participants were asked to encode the position of high-contrast targets embedded in emotional (negative or positive) or neutral pictures. At retrieval, they performed a visual search for targets presented at the same location as during encoding, but at a much lower contrast. Behaviorally, participants detected more accurately targets presented in negative pictures compared to those in positive or neutral pictures. They were also faster in detecting targets presented at encoding in emotional (negative or positive) pictures than in neutral pictures, or targets not presented during encoding (i.e., memory-guided attention effect). At the neural level, we found increased activation in a large circuit of regions involving the dorsal and ventral frontoparietal cortex, insular and parahippocampal cortex, selectively during the detection of targets presented in negative pictures during encoding. We propose that these regions might form an integrated neural circuit recruited to select and process previously encoded target locations (i.e., memory-guided attention sustained by the frontoparietal cortex) embedded in emotional contexts (i.e., emotional contexts recollection supported by the parahippocampal cortex and emotional monitoring supported by the insular cortex). Ultimately, these findings reveal that negative emotions can enhance memory-guided visual search performance by increasing neural activity in a large-scale brain circuit, contributing to disentangle the complex relationship between emotion, attention, and memory.

Resting heart rate variability is associated with neural adaptation when repeatedly exposed to emotional stimuli.

Higher heart rate variability (HRV) at rest is associated with better emotion regulation ability. While the neurovisceral integration model explains this by postulating that HRV can index how the brain adaptively modulates responses to emotional stimuli, neuroimaging studies directly supporting this idea are scarce. We examined the neural correlates of regulating negative and positive emotion in relation to resting HRV based on the neuroimaging and heart rate data of one hundred young adults. The results showed that those with higher HRV better recruit the medial prefrontal cortex while intensifying positive compared to negative emotion. We also examined how individual differences in resting HRV are associated with adjusting brain activity to repeated emotional stimuli. During repeated viewing of emotional images, subjects with higher resting HRV better reduced activity in the medial prefrontal cortex, posterior cingulate gyrus, and angular gyrus, most of which overlapped with the default mode network. This HRV-DMN association was observed during passively viewing emotional images rather than during actively regulating emotion. While the regulating trials can better detect task-induced changes, the viewing trials might approximate resting state, better revealing individual differences. These findings suggest two possibilities: people with higher resting HRV might have a tendency to spontaneously engage with emotion regulation or possess a trait helping emotional arousal fade away.

Multi-ethnic variation in the ties that bind rumination and heart rate variability: Implications for health disparities.

Higher self-reported rumination, a common form of trait perseverative cognition, is linked with lower resting heart rate variability (HRV), which indicates poorer cardiac function and greater disease risk. A meta-analysis and systematic review indicated that in samples with fewer European Americans, the association of rumination with both heart rate and blood pressure was stronger. Thus, trait rumination may be more strongly associated with resting HRV among ethnically minoritized populations. The current study investigated whether differences in the association of self-reported rumination with resting HRV varied by ethnicity in a sample (N = 513; Mage  = 19.41; 226 Women) of self-identified African Americans (n = 110), Asian Americans (n = 84), and European Americans (n = 319). Participants completed a five-minute baseline period to assess resting HRV, followed by the Ruminative Responses Scale, which contains three facets of rumination including brooding, depressive, and reflective rumination. On average, Asian Americans reported higher levels of rumination relative to European Americans. African Americans had higher resting HRV than Asian Americans. Adjusting for covariates, higher self-reported rumination was significantly associated with lower resting HRV in both African and Asian Americans, but not significantly so in European Americans. This finding was consistent for brooding and reflective, but not depressive rumination. Overall, this study lends insight into a psychological mechanism-rumination-that may impact health disparities among ethnically minoritized individuals, contributing to an understanding of how stress gets under the skin among such minoritized populations.

Genetic differences associated with dopamine and serotonin release mediate fear-induced bradycardia in the human brain.

Fear-induced bradycardia, a transient heartbeat deceleration following exposure to threat, is a physiological index observable in humans, especially in fear conditioning experiments. While gaining interest in recent years, it is still currently underemployed in neuroscientific research compared to more popular physiological indices. Besides its use in research, it could also constitute a valuable resource in a clinical psychiatry setting, as many disorders are also characterized by altered heart rate responses. However, differences in fear-induced bradycardia may also be subtended by genetic interindividual differences, thus suggesting precaution when recommending its use in the clinical setting. Here, we discussed the first endeavors that aimed at clarifying the genetic underpinnings of heart rate variations, which suggest that individual genetic differences have a role in defining the characteristics of heart rate responses. Given this, translating heart rate measurements in the clinical setting must be implemented with caution. Future endeavors in this field will aim at identifying these differences even further, thus allowing for more precise clinical interventions.

Error-related cardiac deceleration: Functional interplay between error-related brain activity and autonomic nervous system in performance monitoring.

Coordinated interactions between the central and autonomic nervous systems are crucial for survival due to the inherent propensity for human behavior to make errors. In our ever-changing environment, when individuals make mistakes, these errors can have life-threatening consequences. In response to errors, specific reactions occur in both brain activity and heart rate to detect and correct errors. Specifically, there are two brain-related indicators of error detection and awareness known as error-related negativity and error positivity. Conversely, error-related cardiac deceleration denotes a momentary slowing of heart rate following an error, signaling an autonomic response. However, what is the connection between the brain and the heart during error processing? In this review, we discuss the functional and neuroanatomical connections between the brain and heart markers of error processing, exploring the experimental conditions in which they covary. Given the current limitations of available data, future research will continue to investigate the neurobiological factors governing the brain-heart interaction, aiming to utilize them as combined markers for assessing cognitive control in healthy and pathological conditions.

Culturally compelled coping and depressive symptoms in Black Americans: Examining the role of psychophysiological regulatory capacity.

Given the culture of racism in the United States, Black Americans are often required to use culturally compelled coping (CCC) styles, such as emotional and behavioral restraint and vigilance. Although CCC is adaptive in the face of pervasive racialized stress, it may still negatively impact mental health outcomes, like depression. Studies have found that Black Americans exhibit higher resting heart rate variability (HRV)-a trait-level biomarker of self-regulatory capacity-than White Americans (Hill et al., 2015), which may reflect the additional resources that Black Americans need to regulate given experiences of racialized stress. Theoretically, this should protect against the development of mental health issues, like depression, given that lower resting HRV is typically observed in psychopathology (Beauchaine & Thayer, 2015). However, the literature is mixed on the buffering effects of greater resting HRV on psychopathology for Black Americans (Keen et al., 2015). Thus, we aimed to understand, with data collected from Black Americans between 2015 and 2018, how individual differences in resting HRV and the use of CCC, particularly restraint and vigilance, related to self-reported depressive symptoms. We found that at higher levels of resting HRV, greater use of CCC was associated with higher depressive symptoms. This suggests that CCC strategies may be detrimental to emotional well-being for those who have the capacity-as indexed by higher resting HRV-to engage in these strategies. Hence, the present study provides preliminary evidence that the ways Black Americans are often compelled to cope with racialized stress may be a path to greater depressive symptoms. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Trajectories of depressive symptoms early in the course of bereavement: Patterns, psychosocial factors and risk of prolonged grief.

In the context of bereavement, little is known about the mechanisms that differentiate normative adjustment patterns from those that may indicate potential psychopathology. This study aimed to replicate and extend previous work by (1) characterizing the trajectories of depressive symptoms from 3 to 12 months after the loss of a spouse, (2) examining whether (a) childhood maltreatment and attachment style predicted distinct depression trajectories, and (b) different depression trajectories were associated with the risk of prolonged grief at 12 months post-loss. Recently bereaved individuals (N = 175) completed self-report assessments at 3, 4, 6, and 12-months post-loss. Trajectories of depressive symptoms were estimated using group-based trajectory modelling. Four distinct trajectories of depressive symptoms were identified: (1) resilience (minimal/no depression across time points; 45%), (2) moderate depression-improved (alleviated to 'mild' by 12 months; 31%), (3) severe depression-improved (alleviated to 'moderate' by 12 months; 15%), and (4) chronic depression ('severe' symptoms across time points; 9%). Higher childhood maltreatment predicted a greater likelihood of belonging to the 'severe depression-improved' and 'chronic depression' groups than the 'resilient' and 'moderate depression-improved' groups. Widow(er)s with higher attachment anxiety were more likely to belong to the 'severe depression-improved' and 'chronic depression' groups than the 'resilient' group. The trajectory groups with persistent levels of depressive symptoms up until 6 months were more likely to exhibit prolonged grief at 12 months post-loss. Changes from pre-loss functioning cannot be estimated. Our findings provide insight into the early identification of post-loss prolonged grief.

Resting heart rate variability and emotion regulation difficulties: Comparing Asian Americans and European Americans.

Asian Americans and European Americans differ in emotion regulation (ER), particularly regarding strategies utilized to adaptively engage in ER. Resting heart rate variability (HRV), a biomarker of ER ability, is suggested to differ between Asian Americans and European Americans, but evidence for such differences has been inconsistent. Yet, research has not considered how Asian Americans and European Americans might differ in the well-established link between resting HRV and ER difficulties, which might lend a better understanding of such inconsistencies. In 374 college-aged individuals (66 Asian Americans; 311 European Americans; 190 women; mean age = 19.3 years [Min. 18, Max 38]), we examined if ethnicity moderated the link between resting HRV and self-reported ER difficulties. Resting HRV was obtained during a 5-min resting-baseline period, and ER difficulties were assessed using the Difficulties in ER Scale, which contained six facets of ER difficulties. Adjusting for gender and body mass index, moderation analyses showed a stronger association between resting HRV and ER difficulties in Asian Americans compared to European Americans. When examining facets of ER, ethnicity moderated only the link between resting HRV and difficulties in accessing ER strategies when facing negative emotions. At lower levels of HRV, Asian Americans reported greater difficulties in ER relative to European Americans. This effect diminished and trended in the opposite direction among those with higher HRV. In sum, these results provide novel evidence that higher resting HRV might be particularly important for adaptive ER among Asian Americans - a marginalized ethnic group - in the U.S.

Daily biofeedback to modulate heart rate oscillations affects structural volume in hippocampal subregions targeted by the locus coeruleus in older adults but not younger adults.

Using data from a clinical trial, we tested the hypothesis that daily sessions modulating heart rate oscillations affect older adults' volume of a region-of-interest (ROI) comprised of adjacent hippocampal subregions with relatively strong locus coeruleus (LC) noradrenergic input. Younger and older adults were randomly assigned to one of two daily biofeedback practices for 5 weeks: 1) engage in slow-paced breathing to increase the amplitude of oscillations in heart rate at their breathing frequency (Osc+); 2) engage in self-selected strategies to decrease heart rate oscillations (Osc-). The interventions did not significantly affect younger adults' hippocampal volume. Among older adults, the two conditions affected volume in the LC-targeted hippocampal ROI differentially as reflected in a significant condition x time-point interaction on ROI volume. These condition differences were driven by opposing changes in the two conditions (increased volume in Osc+ and decreased volume in Osc-) and were mediated by the degree of heart rate oscillation during training sessions.

Daily biofeedback to modulate heart rate oscillations affects structural volume in hippocampal subregions targeted by the locus coeruleus in older adults but not younger adults.

Using data from a clinical trial, we tested the hypothesis that daily sessions modulating heart rate oscillations affect older adults' volume of a region-of-interest (ROI) comprised of adjacent hippocampal subregions with relatively strong locus coeruleus (LC) noradrenergic input. Younger and older adults were randomly assigned to one of two daily biofeedback practices for 5 weeks: (1) engage in slow-paced breathing to increase the amplitude of oscillations in heart rate at their breathing frequency (Osc+); (2) engage in self-selected strategies to decrease heart rate oscillations (Osc-). The interventions did not significantly affect younger adults' hippocampal volume. Among older adults, the two conditions affected volume in the LC-targeted hippocampal ROI differentially as reflected in a significant condition × time-point interaction on ROI volume. These condition differences were driven by opposing changes in the two conditions (increased volume in Osc+ and decreased volume in Osc-) and were mediated by the degree of heart rate oscillation during training sessions.

Exhaustion and cardiovascular risk factors: the role of vagally-mediated heart rate variability.

PURPOSE: Exhaustion symptoms are known to be associated with cardiovascular disease (CVD) risk; however, the underlying mechanisms remain unclear. Autonomic imbalance, as indicated by reductions in vagally-mediated heart rate variability (vmHRV), appears to be a valid candidate for such a biological link, as it has been associated with both exhaustion symptoms and CVD risk and mortality. METHODS: The present study examined a potential mediation of vmHRV on the association between exhaustion symptoms and self-reported CVD risk factors as well as the age dependency of this mediation in a large, heterogeneous sample of the Dresden Burnout Study (N = 388; 72.9% females; Mage = 42.61, SD = 11.67). RESULTS: Results indicate that exhaustion symptoms were indirectly associated with CVD risk factors through vmHRV even after adjusting for well-known confounders (i.e., sex, body mass index, depressive symptoms). Moreover, this pattern was significant only among middle-aged (i.e., 54.27 years) and older individuals. CONCLUSIONS: Our findings add to growing evidence that autonomic imbalance may be a key biological link between exhaustion symptoms and CVD risk in middle-aged and older individuals. Implications for public health are discussed.

Daily heart rate variability biofeedback training decreases locus coeruleus MRI contrast in younger adults in a randomized clinical trial.

As an arousal hub region in the brain, the locus coeruleus (LC) has bidirectional connections with the autonomic nervous system. Magnetic resonance imaging (MRI)-based measures of LC structural integrity have been linked to cognition and arousal, but less is known about factors that influence LC structure and function across time. Here, we tested the effects of heart rate variability (HRV) biofeedback, an intervention targeting the autonomic nervous system, on LC MRI contrast and sympathetic activity. Younger and older participants completed daily HRV biofeedback training for five weeks. Those assigned to an experimental condition performed biofeedback involving slow, paced breathing designed to increase heart rate oscillations, whereas those assigned to a control condition performed biofeedback to decrease heart rate oscillations. At the pre- and post-training timepoints, LC contrast was assessed using turbo spin echo MRI scans, and RNA sequencing was used to assess cAMP-responsive element binding protein (CREB)-regulated gene expression in circulating blood cells, an index of sympathetic nervous system signaling. We found that left LC contrast decreased in younger participants in the experimental group, and across younger participants, decreases in left LC contrast were related to the extent to which participants increased their heart rate oscillations during training. Furthermore, decreases in left LC contrast were associated with decreased expression of CREB-associated gene transcripts. On the contrary, there were no effects of biofeedback on LC contrast among older participants in the experimental group. These findings provide novel evidence that in younger adults, HRV biofeedback involving slow, paced breathing can decrease both LC contrast and sympathetic nervous system signaling.

Differential Associations of Childhood Abuse and Neglect With Adult Autonomic Regulation and Mood-Related Pathology.

OBJECTIVE: This study assessed whether different types of childhood maltreatment (i.e., abuse versus neglect) had differential relationships with heart rate variability (HRV) and baroreflex sensitivity. In addition, this study tested the indirect effect of maltreatment subtypes on adult mood-related psychopathology via HRV, and whether these relationships differed in those with HRV above and below established clinical cutoffs. METHODS: Secondary analysis was performed using the Midlife Development in the United States data set ( N = 967; Mage = 55; 58.4% female; 75.9% White). In a single study visit, autonomic measurements were captured at rest, during two cognitive stressors (Stroop and MATH tasks), and during recovery after the tasks. Structural equation modeling was used to assess the relationships between key variables during all three measurement periods. RESULTS: Resting pathways from abuse and neglect to baroreflex sensitivity were nonsignificant, as was the pathway from HRV to mood-related pathology. Notably, greater abuse was significantly predictive of lower HRV (standardized ß = -0.42, p = .009), whereas greater neglect was significantly predictive of higher HRV (standardized ß = 0.32, p = .034). In addition, higher abuse was significantly predictive of greater adult symptoms (standardized ß = 0.39, p < .001), but neglect was not found to be related to adult mood-related pathology. Significant relationships between variables were only found in those with low HRV. CONCLUSIONS: Although cross-sectional, our findings provide further evidence that low HRV may be a transdiagnostic endophenotype for mood-related pathology and suggest that greater differentiation between abuse and neglect is appropriate when investigating the impact of childhood maltreatment on adult health outcomes.

Multimodal neuroimaging data from a 5-week heart rate variability biofeedback randomized clinical trial.

We present data from the Heart Rate Variability and Emotion Regulation (HRV-ER) randomized clinical trial testing effects of HRV biofeedback. Younger (N = 121) and older (N = 72) participants completed baseline magnetic resonance imaging (MRI) including T1-weighted, resting and emotion regulation task functional MRI (fMRI), pulsed continuous arterial spin labeling (PCASL), and proton magnetic resonance spectroscopy (1H MRS). During fMRI scans, physiological measures (blood pressure, pulse, respiration, and end-tidal CO2) were continuously acquired. Participants were randomized to either increase heart rate oscillations or decrease heart rate oscillations during daily sessions. After 5 weeks of HRV biofeedback, they repeated the baseline measurements in addition to new measures (ultimatum game fMRI, training mimicking during blood oxygen level dependent (BOLD) and PCASL fMRI). Participants also wore a wristband sensor to estimate sleep time. Psychological assessment comprised three cognitive tests and ten questionnaires related to emotional well-being. A subset (N = 104) provided plasma samples pre- and post-intervention that were assayed for amyloid and tau. Data is publicly available via the OpenNeuro data sharing platform.

Sex Differences in Neural Correlates of Emotion Regulation in Relation to Resting Heart Rate Variability.

Prior studies suggest that sex differences in emotion regulation (ER) ability contribute to sex disparities in affective disorders. In behavioral studies, females rely more on maladaptive strategies to cope with emotional distress than males. Neuroimaging studies suggest that males more efficiently regulate emotion than females by showing less prefrontal cortex activity (suggesting less effort) for similar amygdala activity (similar regulation outcome). However, physiological studies involving heart rate variability (HRV) indicated that, compared with males, females have higher resting HRV, indicative of parasympathetic dominance and better control of emotion. To help resolve these apparently inconsistent findings, we examined sex differences in how resting HRV relates to brain activity while using cognitive reappraisal, one of the adaptive strategies. Based on 51 males and 49 females, we found that females showed different levels of self-rated emotional intensity and amygdala activity for negative versus positive emotions, while males did not. Females also showed greater overall prefrontal cortex activity but similar levels of amygdala activity compared to males. Sex differences in how resting HRV related to brain activity during ER were evident only during viewing or regulating positive emotion. The results suggest that sex differences in the neural correlates of ER and resting HRV might lie in valence more than arousal modulation.

Sex differences in heart rate and heart rate variability in rats: Implications for translational research.

The present study aimed to investigate sex differences in measures of cardiac chronotropy and heart rate variability (HRV) in 132 young adult wild-type Groningen rats (n = 45 females). Electrocardiographic signals were recorded for 48 h in freely moving rats to quantify heart rate (HR) and inter-beat interval (IBI) as measures of cardiac chronotropy, and time- and frequency-domain HRV parameters as physiological readouts of cardiac vagal modulation. Females showed greater vagally-mediated HRV despite having higher HR and shorter IBI than males during undisturbed conditions. Such differences were evident i) at any given level of HRV, and ii) both during the 12-h light/inactive and 12-h dark/active phase of the daily cycle. These findings replicate the paradoxical cardiac chronotropic control reported by human meta-analytic findings, since one would expect greater vagally-mediated HRV to be associated with lower HR and longer IBI. Lastly, the association between some HRV measures and HR was stronger in female than male rats. Overall, the current study in young adult rats provides data illustrating a sex-dependent association between vagally-mediated HRV and indexes of cardiac chronotropy. The current results i) are in line with human findings, ii) suggest to always consider biological sex in the analysis and interpretation of HRV data in rats, and iii) warrant the use of rats for investigating the neuro-hormonal basis and temporal evolution of the impact of sex on the association between vagally-mediated HRV and cardiac chronotropy, which could inform the human condition.

Resilience to stress across the lifespan: Childhood maltreatment, heart rate variability, and bereavement.

Following a stressful life event, there is considerable variation in how individuals respond and adapt. Multiple models of risk and resilience show that adverse childhood experiences may be associated with an individual's response to stress later in life. While there is considerable support that early adversity can sensitize the stress response system and lead to adverse outcomes later in life, there is mounting evidence that in adolescence and young adulthood, certain biological predispositions to stress may be associated with resilience in the context of subsequent stressors. In this study, we evaluated how individual differences in vagally mediated heart rate variability moderated the relationship between childhood maltreatment and grief among a sample of individuals experiencing a stressful life event (i.e., spousal bereavement) over time. Data were collected at approximately 3, 4.5, and 6.5 months after the death of a spouse (n = 130). Heart rate variability moderated the relationship between childhood maltreatment and grief symptoms over time (b = -0.03, p < .001), such that among individuals with more severe experiences of childhood maltreatment, those with higher heart rate variability had a faster recovery from grief than those with low heart rate variability. This research highlights an overall pattern of resilience among older adult's following spousal bereavement, as well as the relationships between childhood maltreatment, heart rate variability, and differential responses to grief following the loss of a spouse. (PsycInfo Database Record (c) 2023 APA, all rights reserved).