Host in the machine: A neurobiological perspective on psychological stress and cardiovascular disease

Unveiling stress markers: A systematic review investigating psychological stress biomarkers

Psychological stress is a ubiquitous facet of modern life, impacting individuals across diverse contexts and demographics. Understanding its physiological manifestations through biomarkers has gained substantial attention within the scientific community. A comprehensive search was conducted across multiple databases for peer-reviewed articles published within the past decade. Preliminary findings reveal many biomarkers associated with psychological stress across different biological systems, including the hypothalamic-pituitary-adrenal axis, immune system, cardiovascular system, and central nervous system. This systematic review explores psychological, physiological, and biochemical biomarkers associated with stress. Analyzing recent literature, it synthesizes findings across these three categories, elucidating their respective roles in stress response mechanisms. Psychological markers involve subjective assessments like self-reported stress levels, perceived stress scales, or psychometric evaluations measuring anxiety, depression, or coping mechanisms. Physiological markers include heart rate variability, blood pressure, and immune system responses such as cytokine levels or inflammatory markers. Biochemical markers involve hormones or chemicals linked to stress. It includes cortisol, catecholamines, copeptin, salivary amylase, IL-6, and C-reactive protein.

Mastery imagery ability moderates the relationship between heart rate reactivity to acute psychological stress and perceptions of stress and physiological arousal

Imagery has been associated with cardiovascular and psychological responses to stress; however, the mechanisms underlying this association are not fully understood. The present study examined if the ability to image mastering challenging or difficult situations moderated the relationship between heart rate reactivity and perceptions of stress and physiological arousal experienced during acute stress. Four hundred and fifty-eight participants completed a standardized laboratory stress protocol with heart rate being measured throughout. After completing an acute psychological stress task, participants rated how stressed and physiologically aroused they felt (i.e., intensity) and whether they perceived the stress and physiological arousal as being helpful/unhelpful to performance (i.e., interpretation). Mastery imagery ability was assessed by questionnaire. Moderation analyses controlling for gender demonstrated that imagery ability moderated the relationship between heart rate reactivity and interpretation of stress (β = 0.015, p = .003) and perceived physiological arousal (β = 0.013, p = .004). Simple slope analysis indicated that in those with higher imagery ability, heart rate reactivity was associated with stress and arousal being perceived as more positive toward performance. Imagery ability did not moderate the relationship between heart rate reactivity and perceived stress intensity or physiological arousal intensity (p's > .05), but imagery ability did predict lower perceived stress intensity (β = -0.217, p < .001) and perceived physiological arousal intensity (β = -0.172, p < .001). Higher mastery imagery ability may possibly help individuals perceive responses to stress as more beneficial for performance and thus be an effective coping technique.

Stressor-evoked brain activity, cardiovascular reactivity, and subclinical atherosclerosis in midlife adults

Background

Cardiovascular responses to psychological stressors have been separately associated with preclinical atherosclerosis and hemodynamic brain activity patterns across different studies and cohorts; however, what has not been established is whether cardiovascular stress responses reliably link indicators of stressor-evoked brain activity and preclinical atherosclerosis that have been measured in the same individuals. Accordingly, the present study used cross-validation and predictive modeling to test for the first time whether stressor-evoked systolic blood pressure (SBP) responses statistically mediated the association between concurrently measured brain activity and a vascular marker of preclinical atherosclerosis in the carotid arteries.

Methods

624 midlife adults (aged 28-56 years, 54.97% female) from two different cohorts underwent two information-conflict fMRI tasks, with concurrent SBP measures collected. Carotid artery intima-media thickness (CA-IMT) was measured by ultrasonography. A mediation framework that included harmonization, cross-validation, and penalized principal component regression was then employed, while significant areas in possible direct and indirect effects were identified through bootstrapping. Sensitivity analysis further tested the robustness of findings after accounting for prevailing levels of cardiovascular disease risk and brain imaging data quality control.

Results

Task-averaged patterns of hemodynamic brain responses exhibited a generalizable association with CA-IMT, which was mediated by an area-under-the-curve measure of aggregate SBP reactivity. Importantly, this effect held in sensitivity analyses. Implicated brain areas in this mediation included the ventromedial prefrontal cortex, anterior cingulate cortex, insula and amygdala.

Conclusions

These novel findings support a link between stressor-evoked brain activity and preclinical atherosclerosis accounted for by individual differences in corresponding levels of stressor-evoked cardiovascular reactivity.

Exaggerated Peripheral and Systemic Vasoconstriction During Trauma Recall in Posttraumatic Stress Disorder: A Co-Twin Control Study

BACKGROUND

Individuals with posttraumatic stress disorder (PTSD) face an increased risk of cardiovascular disease, but the mechanisms linking PTSD to cardiovascular disease remain incompletely understood. We used a co-twin control study design to test the hypothesis that individuals with PTSD exhibit augmented peripheral and systemic vasoconstriction during a personalized trauma recall task.

METHODS

In 179 older male twins from the Vietnam Era Twin Registry, lifetime history of PTSD and current (last month) PTSD symptoms were assessed. Participants listened to neutral and personalized trauma scripts while peripheral vascular tone (Peripheral Arterial Tone ratio) and systemic vascular tone (e.g., total vascular conductance) were measured. Linear mixed-effect models were used to assess the within-pair relationship between PTSD and vascular tone indices.

RESULTS

The mean age of participants was 68 years, and 19% had a history of PTSD. For the Peripheral Arterial Tone ratio analysis, 32 twins were discordant for a history of PTSD, and 46 were discordant for current PTSD symptoms. Compared with their brothers without PTSD, during trauma recall, participants with a history of PTSD had greater increases in peripheral (β = -1.01, 95% CI [-1.72, -0.30]) and systemic (total vascular conductance: β = -1.12, 95% CI [-1.97, -0.27]) vasoconstriction after adjusting for cardiovascular risk factors. Associations persisted after adjusting for antidepressant medication use and heart rate and blood pressure during the tasks. Analysis of current PTSD symptom severity showed consistent results.

CONCLUSIONS

PTSD is associated with exaggerated peripheral and systemic vasoconstrictor responses to traumatic stress reminders, which may contribute to elevated risk of cardiovascular disease.

Profiles of historical loss and childhood trauma as predictors of mental and cardiometabolic health in American Indian adults

Cardiometabolic disease and mental health conditions are two major contributors to persistent inequities in health and life expectancy for American Indian adults. The atrocities associated with European colonization are linked to intergenerational psychological and emotional wounding (i.e., historical trauma) and high incidence of childhood trauma. Prior work has examined the independent relationships of childhood trauma and thoughts about historical loss with cardiometabolic and mental health in American Indians. In the current work, we used a data-driven approach to identify profiles of childhood trauma and frequency of thoughts about historical loss, and then examined how these profiles related to cardiometabolic and mental health in a sample of American Indian adults from across the United States (N = 727). We found that a profile characterized by high levels of childhood trauma and high frequency of thoughts about historical losses was associated with the greatest risk for mental health conditions. The profile characterized by the highest levels of childhood trauma and by moderate frequency of thoughts about historical losses was associated with the largest risk of cardiometabolic conditions. The findings represent an important first step towards understanding how childhood trauma and thoughts about historical loss may simultaneously inform enduring inequities in American Indian health.

Posttraumatic Stress Disorder Symptoms and Cardiovascular and Brain Health in Women

Importance

Posttraumatic stress disorder (PTSD), cardiovascular disease (CVD), and Alzheimer disease are major public health issues, particularly for women. The implications of PTSD for cardiovascular and brain health for women is poorly understood.

Objective

To assess whether PTSD symptoms among midlife women are associated with carotid intima media thickness (IMT), an indicator of carotid atherosclerosis; brain white matter hyperintensity volume (WMHV), an indicator of brain small vessel disease; and cognitive performance and to test a modifying role of the APOEε4 genotype.

Design, Setting, and Participants

In this cross-sectional study, participants were enrolled between 2016 to 2021 and completed questionnaires (PTSD Checklist-Civilian Version), physical measures, phlebotomy, neuropsychological testing, a carotid ultrasonographic examination, and 3-Tesla brain magnetic resonance imaging. Participants included community-based women ages 45 to 67 years without a history of CVD, stroke, or dementia. Data were analyzed from July 2022 to September 2023.

Exposures

PTSD symptoms.

Main Outcomes and Measures

Outcomes of interest were associations of PTSD symptoms with carotid IMT, brain WMHV, and cognition, assessed in linear regression models. Interactions by APOEε4 were tested. Covariates included age, race and ethnicity, education, and CVD risk factors.

Results

Among 274 participants (mean [SD] age, 59.03 [4.34] years; 6 Asian participants [2.2%]; 48 Black participants [17.5%]; 215 White participants [78.5%]; 5 multiracial participants [1.8%]), 64 participants (24.71%) were APOEε4 genotype carriers. Higher PTSD symptoms were associated with greater carotid IMT (multivariable β = 0.07 [95% CI, 0.01 to 0.13]; P = .03). Associations of PTSD symptoms with neurocognitive outcomes significantly varied by APOEε4 status. Among women with APOEε4, PTSD symptoms were associated with greater whole-brain WMHV (β = 0.96 [95% CI, 0.30 to 1.63]; P = .009), periventricular WMHV (β = 0.90 [95% CI, 0.24 to 1.56]; P = .02), deep WMHV (β = 1.21 [95% CI, 0.23 to 2.20]; P = .01), and frontal WMHV (β = 1.25 [95% CI, 0.05 to 2.45]; P = .04), as well as with poorer cognition, specifically attention and working memory (β = -3.37 [95% CI, -6.12 to -0.62]; P = .02), semantic fluency (β = -6.01 [95% CI, -10.70 to -1.31]; P = .01), perceptual speed (β = -12.73 [95% CI, -20.71 to -4.75]; P = .002), and processing speed (β = -11.05 [95% CI, -17.80 to -4.30]; P = .002) in multivariable models.

Conclusions and Relevance

In this cross-sectional study of midlife women, greater PTSD symptoms were associated with higher carotid atherosclerosis and, among women who were APOEε4 carriers, greater brain small vessel disease and poorer cognitive performance. These findings point to the adverse implications of PTSD symptoms for cardiovascular and neurocognitive health among women in midlife, particularly for women who are APOEε4 carriers.

Associations between klotho and telomere biology in high stress caregivers

Aging biomarkers may be related to each other through direct co-regulation and/or through being regulated by common processes associated with chronological aging or stress. Klotho is an aging regulator that acts as a circulating hormone with critical involvement in regulating insulin signaling, phosphate homeostasis, oxidative stress, and age-related inflammatory functioning. Both klotho and telomere length are biomarkers of biological aging and decrease with age; however, the relationship between them is not well understood. Here we test the association between klotho levels and the telomere length of specific sorted immune cells among a healthy sample of mothers caregiving for a child with autism spectrum disorder (ASD; i.e., experiencing higher caregiving stress) or a child without ASD, covarying age and body mass index, in order to understand if high stress associated with caregiving for a child with an ASD may be involved in any association between these aging biomarkers. In 178 caregiving women (n = 90 high-stress mothers of children with ASD, n = 88 low-stress mothers of neurotypical children), we found that klotho levels were positively associated with telomere length in PBMCs (an effect driven by CD4+ and CD8+CD28- T cells) among high-stress mothers of children with an ASD but not among low-stress mothers of neurotypical children. There were no significant associations between klotho and telomerase activity in either group, across cell types assessed here. Our results suggest that klotho levels and telomere length may be associated through a coordinated downregulation of longevity factors occurring under higher stress caregiving conditions.

In natura heart rate variability predicts subsequent alcohol use in individuals in early recovery from alcohol use disorder

Impairment in autonomic self-regulatory functioning reflected by reduced heart rate variability (HRV) is a common feature of alcohol use disorder (AUD) and is believed to heighten AUD relapse risk. However, to date, no study has explored associations between in natura HRV and subsequent alcohol use among individuals seeking AUD recovery. In this study, 42 adults in the first year of a current AUD recovery attempt were monitored for 4 days using ambulatory electrocardiogram, followed by 90 days of alcohol use monitoring using timeline follow-back. HRV indices (independent variables) reflecting autonomic neurocardiac engagement were calculated from electrocardiogram recordings. Alcohol use (dependent variable) was calculated from timeline follow-back and expressed as per cent days abstinent (PDA). The sample was 73.81% White/European American, 19.05% Black/African American, 4.76% Asian, and 2.38% Other race/Mixed race. As predicted, higher parasympathetically mediated HRV and lower heart rate were associated with greater PDA over 90-day follow-up. Additionally, interactions between these measures and baseline PDA indicated higher parasympathetically mediated HRV and lower heart rate mitigated the deleterious positive association between baseline and follow-up alcohol use. Including factors known to influence alcohol use and/or HRV in the models did not meaningfully alter their results. Findings are consistent with psychophysiological theories implicating autonomic self-regulatory functioning in AUD treatment outcomes and suggest that select HRV indices may have utility as indicants of risk for alcohol use lapse in individuals in early AUD recovery. Findings provide theoretical support for HRV Biofeedback for this population, which exercises the psychophysiological systems that support self-regulation.

Does light physical activity reduce blood pressure responses to laboratory stressors?

Individuals exhibiting exaggerated blood pressure responses to stress are at increased risk for later cardiovascular disease. Engagement in brief bouts of moderate-to-vigorous physical activity may reduce instances of these exaggerated blood pressure responses. While observational work has shown that periods of light physical activity may also be associated with reduced blood pressure responses to stress in daily life, the few experimental studies involving light physical activity have methodological limitations that temper conclusions. The current investigation sought to understand the effects of brief bouts of light physical activity on blood pressure responses to psychological stress. In a between-person, single-session experimental design, 179 healthy, young adults were randomized to 15 min of light physical activity, moderate physical activity, or sitting before engaging in a 10-min computerized Stroop Color-Word Interference Task. Blood pressure readings were collected throughout the study session. Surprisingly, the light physical activity participants showed higher systolic blood pressure responses to stress than control participants by 2.9 mmHg (F (2, 174) = 3.49, ηp 2  = 0.038, p = .03), whereas no significant differences were shown between moderate physical activity and control groups (F (2, 174) = 2.59, ηp 2  = 0.028, p = .078). These findings show that light physical activity may not be related to reduced blood pressure responses to stress in an experimental session involving healthy, college-aged adults and question the extent to which brief bouts of physical activity may reduce acute blood pressure responses to stress.

Racism, shame, and stress reactivity among young black women

Black women experience disproportional rates of cardiovascular disease (CVD) warranting further exploration of CVD risk factors. Growing evidence suggests acute stress reactivity studies may elucidate the mechanisms driving psychosocial correlates of CVD risks. Race-related stress has been identified as a CVD risk factor among Black women though recent evidence suggests emotions may facilitate these risks. Black women may be vulnerable to shame related to frequent racist experiences. Yet, no study to date has examined racism, shame, and stress reactivity in this population. The current study utilized mixed linear models to test for time and group effects of racism and shame on stress reactivity (e.g., cortisol and C-reactive protein [CRP]) among 34 Black women who completed the Trier Social Stress Test. Tests for two-way interactions (i.e., shame by racism) were also performed. Significant time and group effects were observed for shame and racism on stress reactivity. Black women who experienced greater lifetime racism, stress appraised, but lower racism during the past year, exhibited greater CRP responses. Black women who experienced high levels of shame and racism during the past year and their lifetime demonstrated greater cortisol reactivity. These results prompt further research on racism and shame as CVD risk factors among Black women.

A healthy mind in a healthy body: Effects of arteriosclerosis and other risk factors on cognitive aging and dementia

In this review we start from the assumption that, to fully understand cognitive aging, it is important to embrace a holistic view, integrating changes in bodily, brain, and cognitive functions. This broad view can help explain individual differences in aging trajectories and could ultimately enable prevention and remediation strategies. As the title of this review suggests, we claim that there are not only indirect but also direct effects of various organ systems on the brain, creating cascades of phenomena that strongly contribute to age-related cognitive decline. Here we focus primarily on the cerebrovascular system, because of its direct effects on brain health and close connections with the development and progression of Alzheimer's Disease and other types of dementia. We start by reviewing the main cognitive changes that are often observed in normally aging older adults, as well as the brain systems that support them. Second, we provide a brief overview of the cerebrovascular system and its known effects on brain anatomy and function, with a focus on aging. Third, we review genetic and lifestyle risk factors that may affect the cerebrovascular system and ultimately contribute to cognitive decline. Lastly, we discuss this evidence, review limitations, and point out avenues for additional research and clinical intervention.

Multivariate Brain Activity while Viewing and Reappraising Affective Scenes Does Not Predict the Multiyear Progression of Preclinical Atherosclerosis in Otherwise Healthy Midlife Adults

Cognitive reappraisal is an emotion regulation strategy that is postulated to reduce risk for atherosclerotic cardiovascular disease (CVD), particularly the risk due to negative affect. At present, however, the brain systems and vascular pathways that may link reappraisal to CVD risk remain unclear. This study thus tested whether brain activity evoked by using reappraisal to reduce negative affect would predict the multiyear progression of a vascular marker of preclinical atherosclerosis and CVD risk: carotid artery intima-media thickness (CA-IMT). Participants were 176 otherwise healthy adults (50.6% women; aged 30-51 years) who completed a functional magnetic resonance imaging task involving the reappraisal of unpleasant scenes from the International Affective Picture System. Ultrasonography was used to compute CA-IMT at baseline and a median of 2.78 (interquartile range, 2.67 to 2.98) years later among 146 participants. As expected, reappraisal engaged brain systems implicated in emotion regulation. Reappraisal also reduced self-reported negative affect. On average, CA-IMT progressed over the follow-up period. However, multivariate and cross-validated machine-learning models demonstrated that brain activity during reappraisal failed to predict CA-IMT progression. Contrary to hypotheses, brain activity during cognitive reappraisal to reduce negative affect does not appear to forecast the progression of a vascular marker of CVD risk.

Supplementary Information

The online version contains supplementary material available at 10.1007/s42761-021-00098-y.

Resting (Tonic) Blood Pressure Is Associated With Sensitivity to Imagined and Acute Experiences of Social Pain: Evidence From Three Studies

Social pain is a common experience that has potent implications for health. However, individuals differ in their sensitivity to social pain. Recent evidence suggests that sensitivity to social pain varies according to a biological factor that modulates sensitivity to physical pain: resting (tonic) blood pressure. The current studies extended this evidence by testing whether blood pressure relates to sensitivity to imagined (Study 1: N = 762, 51% female adults) and acute (Study 2, preregistered: N = 204, 57% female adults) experiences of social pain and whether associations extend to general emotional responding (Studies 1-3; Study 3: N = 162, 59% female adults). In line with prior evidence, results showed that higher resting blood pressure was associated with lower sensitivity to social pain. Moreover, associations regarding blood pressure and sensitivity to social pain did not appear to be explained by individual differences in general emotional responding. Findings appear to be compatible with the interpretation that social and physical pain share similar cardiovascular correlates and may be modulated by convergent interoceptive pathways.

Intimate Relationships and Coronary Heart Disease: Implications for Risk, Prevention, and Patient Management

Purpose of Review

Research and clinical services addressing psychosocial aspects of coronary heart disease (CHD) typically emphasize individuals, focusing less on the context of intimate relationships such as marriage and similar partnerships. This review describes current evidence regarding the role of intimate relationships in the development, course, and management of CHD.

Recent Findings

Having an intimate partner is associated with reduced risk of incident CHD and a better prognosis among patients, but strain (e.g., conflict) and disruption (i.e., separation, divorce) in these relationships are associated with increased risk and poor outcomes. These associations likely reflect mechanisms involving health behavior and the physiological effects of emotion and stress. Importantly, many other well-established psychosocial risk and protective factors (e.g., low SES, job stress, depression, and optimism) are strongly related to the quality of intimate relationships, and these associations likely contribute to the effects of those other psychosocial factors. For better or worse, intimate partners can also affect the outcome of efforts to alter health behaviors (physical activity, diet, smoking, and medication adherence) central in the prevention and management CHD. Intimate partners also influence—and are influenced by—stressful aspects of acute coronary crises and longer-term patient adjustment and management.

Summary

Evidence on each of these roles of intimate relationships in CHD is considerable, but direct demonstrations of the value of couple assessments and interventions are limited, although preliminary research is promising. Research needed to close this gap must also address issues of diversity, disparities, and inequity that have strong parallels in CHD and intimate relationships.

Obesity, Psychological Distress, and Resting State Connectivity of the Hippocampus and Amygdala Among Women With Early-Stage Breast Cancer

Objective

Overweight and obesity [body mass index (BMI) ≥ 25 kg/m2] are associated with poorer prognosis among women with breast cancer, and weight gain is common during treatment. Symptoms of depression and anxiety are also highly prevalent in women with breast cancer and may be exacerbated by post-diagnosis weight gain. Altered brain function may underlie psychological distress. Thus, this secondary analysis examined the relationship between BMI, psychological health, and resting state functional connectivity (rsFC) among women with breast cancer.

Methods

The sample included 34 post-menopausal women newly diagnosed with Stage 0-IIa breast cancer (Mage = 63.59 ± 5.73) who were enrolled in a 6-month randomized controlled trial of aerobic exercise vs. usual care. At baseline prior to randomization, whole-brain analyses were conducted to evaluate the relationship between BMI and seed-to-voxel rsFC of the hippocampus and amygdala. Connectivity values from significant clusters were then extracted and examined as predictors of self-reported depression and anxiety.

Results

Mean BMI was in the obese range (M = 31.83 ± 6.62). For both seeds examined, higher BMI was associated with lower rsFC with regions of prefrontal cortex (PFC), including ventrolateral PFC (vlPFC), dorsolateral PFC, and superior frontal gyrus (z range = 2.85-4.26). Hippocampal connectivity with the vlPFC was negatively correlated with self-reported anxiety (β = 0.47, p < 0.01).

Conclusion

Higher BMI was associated with lower hippocampal and amygdala connectivity to regions of PFC implicated in cognitive control and emotion regulation. BMI-related differences in hippocampal and amygdala connectivity following a recent breast cancer diagnosis may relate to future worsening of psychological functioning during treatment and remission. Additional longitudinal research exploring this hypothesis is warranted.

How exposure to chronic stress contributes to the development of type 2 diabetes: A complexity science approach

Chronic stress contributes to the onset of type 2 diabetes (T2D), yet the underlying etiological mechanisms are not fully understood. Responses to stress are influenced by earlier experiences, sex, emotions and cognition, and involve a complex network of neurotransmitters and hormones, that affect multiple biological systems. In addition, the systems activated by stress can be altered by behavioral, metabolic and environmental factors. The impact of stress on metabolic health can thus be considered an emergent process, involving different types of interactions between multiple variables, that are driven by non-linear dynamics at different spatiotemporal scales. To obtain a more comprehensive picture of the links between chronic stress and T2D, we followed a complexity science approach to build a causal loop diagram (CLD) connecting the various mediators and processes involved in stress responses relevant for T2D pathogenesis. This CLD could help develop novel computational models and formulate new hypotheses regarding disease etiology.

A Systematic and Comparative Review of Behavior Change Strategies in Stress Management Apps: Opportunities for Improvement

Stress is one of the significant triggers of several physiological and psychological illnesses. Mobile health apps have been used to deliver various stress management interventions and coping strategies over the years. However, little work exists on persuasive strategies employed in stress management apps to promote behavior change. To address this gap, we review 150 stress management apps on both Google Play and Apple's App Store in three stages. First, we deconstruct and compare the persuasive/behavior change strategies operationalized in the apps using the Persuasive Systems Design (PSD) framework and Cialdini's Principles of Persuasion. Our results show that the most frequently employed strategies are personalization, followed by self-monitoring, and trustworthiness, while social support strategies such as competition, cooperation and social comparison are the least employed. Second, we compare our findings within the stress management domain with those from other mental health domains to uncover further insights. Finally, we reflect on our findings and offer eight design recommendations to improve the effectiveness of stress management apps and foster future research.

The Stressed Brain: Neural Underpinnings of Social Stress Processing in Humans

As humans, we face a variety of social stressors on a regular basis. Given the established role of social stress in influencing physical and psychological functioning, researchers have focused immense efforts on understanding the psychological and physiological changes induced by exposure to acute social stressors. With the advancement of functional magnetic resonance imaging (fMRI), more recent work has sought to identify the neural correlates of processing acute social stress. In this review, we provide an overview of research on the neural underpinnings of social stress processing to date. Specifically, we summarize research that has examined the neural underpinnings of three types of social stressors commonly studied in the literature: social rejection, social evaluation, and racism-related stress. Within our discussion of each type of social stressor, we describe the methods used to induce stress, the brain regions commonly activated among studies investigating that type of stress, and recommendations for future work. This review of the current literature identifies activity in midline regions in both prefrontal and parietal cortices, as well as lateral prefrontal regions, as being associated with processing social rejection. Activity in the insula, thalamus, and inferior frontal gyrus is often found in studies using social evaluation tasks. Finally, racism-related stress is associated with activity in the ventrolateral prefrontal cortex and rostral anterior cingulate cortex. We conclude by taking a "30,000-foot view" of this area of research to provide suggestions for the future of research on the neuroscience of social stress.

Closing the brain-heart loop: Towards more holistic models of addiction and addiction recovery

Much research seeks to articulate the brain structures and pathways implicated in addiction and addiction recovery. Prominent neurobiological models emphasize the interplay between cortical and limbic brain regions as a main driver of addictive processes, but largely do not take into consideration sensory and visceral information streams that link context and state to the brain and behavior. Yet these brain-body information streams would seem to be necessary elements of a comprehensive model of addiction. As a starting point, we describe the overlap between one current model of addiction circuitry and the neural network that not only regulates cardiovascular system activity but also receives feedback from peripheral cardiovascular processes through the baroreflex loop. We highlight the need for neurobiological, molecular, and behavioral studies of neural and peripheral cardiovascular signal integration during the experience of internal states and environmental contexts that drive alcohol and other drug use behaviors. We end with a call for systematic, mechanistic research on the promising, yet largely unexamined benefits to addiction treatment of neuroscience-informed, adjunctive interventions that target the malleability of the cardiovascular system to alter brain processes.

Kindness as a Stress Reduction-Health Promotion Intervention: A Review of the Psychobiology of Caring

Chronic stress is a ubiquitous problem shouldered by many people worldwide. Although the stressors are myriad (eg, loneliness, finances, health, discrimination), the corporal response to them either causes or exacerbates mental and physical illness, including depression, anxiety, and cardiovascular disease. Identifying efficient ways to help people buffer their response and promote resilience and wellness is critical to improving overall health. Positive interpersonal connection is a proven way to promote resilience and happiness. It is associated with decreased mortality and markers of better health. Kindness and caring are prosocial behaviors that build positive interpersonal connections and can uplift both the giver and receiver. Simply seeing kindness and caring activates the neuropsychology of kindness, elevating the viewer and promoting generosity, interpersonal connection, and inclusion. That augmenting positive emotions, enhancing interpersonal connection, and inducing prosocial behavior change are possible through seeing kindness opens the opportunity to bolster resilience in higher stress settings like health care. In a recent study, watching kindness media in a health care setting rapidly increased self-reported feelings of happiness, calm, gratitude, and being inspired. Viewers were significantly more generous. Providing staff and patients with a nonjudgmental lift to enhance caring interactions through kindnesses media can be an important, low-cost adjunct to improving the healthcare environment.

Does allostatic load predict incidental coronary events differently among sexes?

Background

One measure to quantify the degree of dysregulation is allostatic load (AL). Typically, AL incorporates information on diverse biomarkers and is associated with health outcomes such as cardiovascular diseases or the incidence of coronary events (C-E).

Aims

This study investigates the predictive performance of different AL scoring methods on the incidence of coronary events (C-E). This study also elaborates sex differences in the baseline risks of C-E and the AL associated risks of C-E.

Design

Longitudinal data analysis of the Heinz Nixdorf Recall Study (Risk Factors, Evaluation of Coronary Calcification, and Lifestyle) of 4327 participants free of C-E at study baseline aged 45–75. The data contains over 13 biomarkers measuring AL.

Methods

After conducting multiple imputations on missing values on AL for 826 participants, the analysis sample consisted of N = 4327 participants. We applied the two most commonly used methods of AL scoring AL (count-based and Z-score) and a recently developed logistic regression weighting method (LRM) approach. Cox regression was used to predict the incidence of C-E for each AL score. Results were estimated without (M0) and with (M1) covariate adjustment, and in a final model (M2), with an interaction between AL and sex.

Results

We found no violation of the proportional hazard assumption and significant differences in the survival curves between the sexes for C-E (Log-rank test: prob. > Chi² = 0.000). In M0, all AL-scoring methods predicted C-E significantly, with the LRM based AL-score having the best performance (hazard ratio = 3.133; CI: [2.630, 3.732]; Somer's D = 0.717). After covariate inclusion, differences between the scoring methods levelled, though the count-based method and LRM performed better than the Z-scoring method. The interaction analysis in M2 showed a significant multiplicative interaction for the count-based method (1.254; [1.066, 1.475]) and for the LRM (1.746; [1.132, 2.692]). The additive relative excess risk due to interaction (RERI) measure was negative for the count-based method (RERI = −1.967; [-3.778; −0.156]) and the LRM (RERI = −1.909 [-3.910; 0.091]), indicating subadditivity.

Conclusion

AL scores are suitable for predicting C-E. Differences between the AL-scoring algorithms were only present after including interactions. We value the count-based method as suitable for clinical practice since its calculation is relatively simple, and performance was among the best. Interaction analysis revealed that despite strong sex differences in baseline C-E, the effect of AL is more pronounced for females at high levels of AL; thus, females could benefit more from a potential intervention on AL. We suggest further investigation of sex differences concerning the mediation by physiological and psychological intermediates.

Cardiovascular Stress Reactivity and Health: Recent Questions and Future Directions

OBJECTIVE

High cardiovascular reactions to psychological stress are associated with the development of hypertension, systemic atherosclerosis, and cardiovascular disease. However, it has become apparent that low biological stress reactivity also may have serious consequences for health, although less is known about the mechanisms of this. The objectives of this narrative review and opinion article are to summarize and consider where we are now in terms of the usefulness of the reactivity hypothesis and reactivity research, given that both ends of the reactivity spectrum seem to be associated with poor health, and to address some of the key criticisms and future challenges for the research area.

METHODS

This review is authored by the members of a panel discussion held at the American Psychosomatic Society meeting in 2019, which included questions such as the following: How do we measure high and low reactivity? Can high reactivity ever indicate better health? Does low or blunted reactivity simply reflect less effort on task challenges? Where does low reactivity originate from, and what is a low reactor?

RESULTS

Cardiovascular (and cortisol) stress reactivity are used as a model to demonstrate an increased understanding of the different individual pathways from stress responses to health/disease and show the challenges of how to understand and best use the reconstruction of the long-standing reactivity hypothesis given recent data.

CONCLUSIONS

This discussion elucidates the gaps in knowledge and key research issues that still remain to be addressed in this field, and that systematic reviews and meta-analyses continue to be required.

Effects of arousal reappraisal on the anxiety responses to stress: Breaking the cycle of negative arousal intensity and arousal interpretation

Arousal reappraisal has been shown to be an effective strategy during stress to improve anxiety. However, the exact psychological mechanism through which arousal reappraisal improves anxiety is unknown. In a large, cross-sectional study (Study 1, N = 455) participants engaged in an acute psychological stress task and rated their levels of physiological arousal, cognitive anxiety, and somatic anxiety, and whether they perceived this physiological arousal, cognitive anxiety, and somatic anxiety as helpful or hurtful (i.e., interpretation). Structural equation models supported a previously hypothesized model demonstrating that higher levels of physiological arousal were interpreted more negatively and this negative interpretation was associated with higher levels of anxiety intensity and more negative interpretations of anxiety. In an independent sample (Study 2, N = 155), participants were randomly assigned to an arousal reappraisal intervention or control condition prior to engaging in the psychological stress task. Results indicated that arousal reappraisal resulted in more positive interpretations of physiological arousal and anxiety. Results also supported a previously hypothesized model demonstrating that arousal reappraisal 'broke' the connection between physiological arousal intensity and physiological arousal interpretation. The present studies suggest that arousal reappraisal could possibly be acting through improving interpretations of physiological arousal symptoms.

Emotional Granularity Increases With Intensive Ambulatory Assessment: Methodological and Individual Factors Influence How Much

Individuals differ in their ability to create instances of emotion that are precise and context-specific. This skill - referred to as emotional granularity or emotion differentiation - is associated with positive mental health outcomes. To date, however, little work has examined whether and how emotional granularity might be increased. Emotional granularity is typically measured using data from experience sampling studies, in which participants are prompted to report on their emotional experiences multiple times per day, across multiple days. This measurement approach allows researchers to examine patterns of responses over time using real-world events. Recent work suggests that experience sampling itself may facilitate increases in emotional granularity in depressed individuals, such that it may serve both empirical and interventional functions. We replicated and extended these findings in healthy adults, using data from an intensive ambulatory assessment study including experience sampling, peripheral physiological monitoring, and end-of-day diaries. We also identified factors that might distinguish individuals who showed larger increases over the course of experience sampling and examined the extent of the impact of these factors. We found that increases in emotional granularity over time were facilitated by methodological factors, such as number of experience sampling prompts responded to per day, as well as individual factors, such as resting respiratory sinus arrhythmia. These results provide support for the use of experience sampling methods to improve emotional granularity, raise questions about the boundary conditions of this effect, and have implications for the conceptualization of emotional granularity and its relationship with emotional health.

Affective brain patterns as multivariate neural correlates of cardiovascular disease risk

This study tested whether brain activity patterns evoked by affective stimuli relate to individual differences in an indicator of pre-clinical atherosclerosis: carotid artery intima-media thickness (CA-IMT). Adults (aged 30-54 years) completed functional magnetic resonance imaging (fMRI) tasks that involved viewing three sets of affective stimuli. Two sets included facial expressions of emotion, and one set included neutral and unpleasant images from the International Affective Picture System (IAPS). Cross-validated, multivariate and machine learning models showed that individual differences in CA-IMT were partially predicted by brain activity patterns evoked by unpleasant IAPS images, even after accounting for age, sex and known cardiovascular disease risk factors. CA-IMT was also predicted by brain activity patterns evoked by angry and fearful faces from one of the two stimulus sets of facial expressions, but this predictive association did not persist after accounting for known cardiovascular risk factors. The reliability (internal consistency) of brain activity patterns evoked by affective stimuli may have constrained their prediction of CA-IMT. Distributed brain activity patterns could comprise affective neural correlates of pre-clinical atherosclerosis; however, the interpretation of such correlates may depend on their psychometric properties, as well as the influence of other cardiovascular risk factors and specific affective cues.

Investigating the relationship between emotional granularity and cardiorespiratory physiological activity in daily life

Emotional granularity describes the ability to create emotional experiences that are precise and context-specific. Despite growing evidence of a link between emotional granularity and mental health, the physiological correlates of granularity have been under-investigated. This study explored the relationship between granularity and cardiorespiratory physiological activity in everyday life, with particular reference to the role of respiratory sinus arrhythmia (RSA), an estimate of vagal influence on the heart often associated with positive mental and physical health outcomes. Participants completed a physiologically triggered experience-sampling protocol including ambulatory recording of electrocardiogram, impedance cardiogram, movement, and posture. At each prompt, participants generated emotion labels to describe their current experience. In an end-of-day survey, participants elaborated on each prompt by rating the intensity of their experience on a standard set of emotion adjectives. Consistent with our hypotheses, individuals with higher granularity exhibited a larger number of distinct patterns of physiological activity during seated rest, and more situationally precise patterns of activity during emotional events: granularity was positively correlated with the number of clusters of cardiorespiratory physiological activity discovered in seated rest data, as well as with the performance of classifiers trained on event-related changes in physiological activity. Granularity was also positively associated with RSA during seated rest periods, although this relationship did not reach significance in this sample. These findings are consistent with constructionist accounts of emotion that propose concepts as a key mechanism underlying individual differences in emotional experience, physiological regulation, and physical health.

Chronic Stress-Related Neural Activity Associates With Subclinical Cardiovascular Disease in a Community-Based Cohort: Data From the Washington, D.C. Cardiovascular Health and Needs Assessment

Background: Psychosocial stress correlates with cardiovascular (CV) events; however, associations between physiologic measures of stressors and CVD remain incompletely understood, especially in racial/ethnic minority populations in resource-limited neighborhoods. We examined associations between chronic stress-related neural activity, measured by amygdalar ¹⁸Fluorodeoxyglucose (¹⁸FDG) uptake, and aortic vascular FDG uptake (arterial inflammation measure) in a community-based cohort.

Methods: Forty participants from the Washington, DC CV Health and Needs Assessment (DC-CHNA), a study of a predominantly African-American population in resource-limited urban areas and 25 healthy volunteers underwent detailed phenotyping, including ¹⁸FDG PET/CT for assessing amygdalar activity (AmygA), vascular FDG uptake, and hematopoietic (leukopoietic) tissue activity. Mediation analysis was used to test whether the link between AmygA and vascular FDG uptake was mediated by hematopoietic activity.

Results: AmygA (1.11 ± 0.09 vs. 1.05 ± 0.09, p = 0.004) and vascular FDG uptake (1.63 ± 0.22 vs. 1.55 ± 0.17, p = 0.05) were greater in the DC-CHNA cohort compared to volunteers. Within the DC-CHNA cohort, AmygA associated with vascular FDG uptake after adjustment for Framingham score and body mass index (β = 0.41, p = 0.015). The AmygA and aortic vascular FDG uptake relationship was in part mediated by splenic (20.2%) and bone marrow (11.8%) activity.

Conclusions: AmygA, or chronic stress-related neural activity, associates with subclinical CVD risk in a community-based cohort. This may in part be mediated by the hematopoietic system. Our findings of this hypothesis-generating study are suggestive of a potential relationship between chronic stress-related neural activity and subclinical CVD in an African American community-based population. Taken together, these findings suggest a potential mechanism by which chronic psychosocial stress, such as stressors that can be experienced in adverse social conditions, promotes greater cardiovascular risk amongst resource-limited, community-based populations most impacted by cardiovascular health disparities. However, larger prospective studies examining these findings in other racially and ethnically diverse populations are necessary to confirm and extend these findings.

Insight Into the Hispanic Paradox: The Language Hypothesis

Hispanics have a lower burden of heart disease than would be predicted from their risk factors. Explanations for this phenomenon, the Hispanic paradox, focus on specific characteristics of the culture that affect stress appraisal and accumulation, including social connections. Features of culture evolve in the context of language, which influences the way emotions are appraised and expressed. The Spanish language, a unifying component defining Hispanic cultures, has unique features that may promote emotional expression, expand the emotional concepts implicated in the construction of emotion, and influence the appraisal of stress. Under chronic stress conditions, sustained responses can become maladaptive, leading to disease. Features of the Spanish language allow its speakers a wide range of emotion schemas by virtue of its emotion lexicon, the ability to easily minimize or exaggerate expressions, and ease in considering hypothetical situations with the use of the subjunctive. The hypothesis here proposes that the Spanish language is directly and indirectly (via culture) responsible for mitigating some of the effects of acute stress responses in Hispanics and, therefore, limits stress accumulation and is partly responsible for the Hispanic paradox.

Neurobiological Pathways Linking Acute Mental Stress to Impairments in Executive Function in Individuals with Coronary Artery Disease

BACKGROUND

Individuals with coronary artery disease (CAD) have worse executive function compared to the general population but the mechanisms are unknown.

OBJECTIVE

To investigate the role of acute mental stress (MS) on the executive function of patients with CAD.

METHODS

Participants with stable CAD underwent acute MS testing with simultaneous peripheral vascular function measurements and brain imaging using high resolution-positron emission tomography. Digital pulse wave amplitude was continuously measured using peripheral artery tonometry (PAT, Itamar Inc). Stress/rest PAT ratio (sPAT) of pulse wave amplitude during MS/baseline was calculated as a measure of microvascular constriction during MS. Plasma levels of catecholamine and interleukin-6 were assessed at baseline and after MS. Executive function was assessed both at baseline and at 2 years follow-up using the Trail Making Test parts A and B.

RESULTS

We studied 389 individuals with brain data available for 148 participants. Of this population follow-up cognitive assessments were performed in 226 individuals (121 with brain imaging). After multivariable adjustment for baseline demographics, risk factors, and medication use, a lower sPAT, indicating greater vasoconstriction, a higher inferior frontal lobe activation with MS, and increases in norepinephrine and IL-6 levels with MS were all independently associated with greater time to complete Trail B test.-38.4pt.

CONCLUSION

In response to acute MS, greater peripheral vasoconstriction, higher inferior frontal lobe brain activation, and increases in the levels of norepinephrine and IL-6 are associated with worse executive function.

Cardiac sympathetic activation and parasympathetic withdrawal during psychosocial stress exposure in 6-month-old infants

Infant autonomic reactivity to stress is a potential predictor of later life health complications, but research has not sufficiently examined sympathetic activity, controlled for effects of physical activity and respiration, or studied associations among autonomic adjustments, cardiac activity, and affect in infants. We studied 278 infants during the repeated Still-Face Paradigm, a standardized stressor, while monitoring cardiac activity (ECG) and respiratory pattern (respiratory inductance plethysmography). Video ratings of physical activity and affect were also performed. Respiratory sinus arrhythmia (RSA) and T-wave amplitude (TWA) served as noninvasive indicators of cardiac parasympathetic and sympathetic activity, respectively. Responses were compared between infants who completed two still-face exposures and those who terminated after one exposure due to visible distress. Findings, controlled for physical activity, showed robust reductions in respiration-adjusted RSA and TWA, with more tonic attenuation of TWA. Infants completing only one still-face trial showed more pronounced autonomic changes and less recovery from stress. They also showed elevated minute ventilation, suggesting hyperventilation. Both reductions in adjusted RSA and TWA contributed equally to heart rate changes and were associated with higher negative and lower positive affect. These associations were more robust in the group of distressed infants unable to complete both still-face trials. Thus, cardiac sympathetic activation and parasympathetic withdrawal are part of the infant stress response, beyond associated physical activity and respiration changes. Their association with cardiac chronotropy and affect increases as infants' distress level increases. This excess reactivity to social stress should be examined as a predictor of future cardiovascular disease.

Social support, social participation, and cardiovascular reactivity to stress in the Midlife in the United States (MIDUS) study

This study tested two hypotheses of associations between dimensions of social connectedness and cardiovascular reactivity to acute stress: (1) high social support predicts diminished cardiovascular responses to stress (i.e., the stress-buffering model of social support), and (2) diminished cardiovascular responses predict lower social participation, a form of motivated behaviour. Participants (N = 606) in the main Midlife in the United States study completed measures of social support and social participation and underwent psychophysiological stress testing. In unadjusted analyses, social support was positively, rather than inversely, associated with reactivity. Results withstood adjustment for several control variables, but not for depressive symptoms, which was associated with diminished reactivity. Further, diminished reactivity was associated with lower social participation, but not in fully adjusted models. No robust evidence was observed for either the stress-buffering model, or for an association between diminished reactivity and lower social participation. The implications for our understanding of links between social connectedness and cardiovascular reactivity are discussed.

Best practices for stress measurement: How to measure psychological stress in health research

Despite the strong evidence linking psychological stress to disease risk, health researchers often fail to include psychological stress in models of health. One reason for this is the incorrect perception that the construct of psychological stress is too vague and broad to accurately measure. This article describes best practices in stress measurement, detailing which dimensions of stressor exposures and stress responses to capture, and how. We describe when to use psychological versus physiological indicators of stress. It is crucial that researchers across disciplines utilize the latest methods for measuring and describing psychological stress in order to build a cumulative science.

Cardiac vagal control mediates the relation between past depression and blood pressure several years later among young adults

Depression has been associated with high blood pressure (BP). However, the mechanisms of the relation between depression and high BP are unclear. We therefore examined whether impaired cardiac vagal control, indexed as low levels of resting respiratory sinus arrhythmia (RSA), serves as a route from depression to high BP. The sample included 125 subjects with histories of depression (probands), 123 never depressed siblings of probands (high-risk siblings), and 156 controls. Resting RSA was assessed at Time 1 (T1) along with BP when subjects were adolescents (M_age  = 16.3 years); systolic and diastolic BP (SBP and DBP) were measured again at Time 2 (T2) when subjects were young adults (M_age  = 22.3 years). Linear mixed-effects models were used to examine the group differences in resting RSA and T2 BP outcomes and to test for RSA mediation of the relation between depression (history or being at high risk) and BP. Resting RSA was lower among probands than controls but was similar among high-risk siblings and controls, while the subject groups did not differ in T2 SBP or DBP. Controlling for T1 BP, depression history indirectly affected T2 DBP (but not SBP) through resting RSA. The findings suggest that, although the direct detrimental effects of depression on BP are not yet evident in young adulthood, among those with depression histories, impaired cardiac vagal control appears to serve as a mechanism of elevated DBP.

Disruption of Neural Homeostasis as a Model of Relapse and Recurrence in Late-Life Depression

The significant public health burden associated with late-life depression (LLD) is magnified by the high rates of recurrence. In this manuscript, we review what is known about recurrence risk factors, conceptualize recurrence within a model of homeostatic disequilibrium, and discuss the potential significance and challenges of new research into LLD recurrence. The proposed model is anchored in the allostatic load theory of stress. We review the allostatic response characterized by neural changes in network function and connectivity and physiologic changes in the hypothalamic-pituitary-adrenal axis, autonomic nervous system, immune system, and circadian rhythm. We discuss the role of neural networks' instability following treatment response as a source of downstream disequilibrium, triggering and/or amplifying abnormal stress response, cognitive dysfunction and behavioral changes, ultimately precipitating a full-blown recurrent episode of depression. We propose strategies to identify and capture early change points that signal recurrence risk through mobile technology to collect ecologically measured symptoms, accompanied by automated algorithms that monitor for state shifts (persistent worsening) and variance shifts (increased variability) relative to a patient's baseline. Identifying such change points in relevant sensor data could potentially provide an automated tool that could alert clinicians to at-risk individuals or relevant symptom changes even in a large practice.

Allostasis: A Brain-Centered, Predictive Mode of Physiological Regulation

Although the concept of allostasis was proposed some 30 years ago, doubts persist about its precise meaning and whether it is useful. Here we review the concept in the context of recent studies as a strategy to efficiently regulate physiology and behavior. The brain, sensing the internal and external milieu, and consulting its database, predicts what is likely to be needed; then, it computes the best response. The brain rewards a better-than-predicted result with a pulse of dopamine, thereby encouraging the organism to learn effective regulatory behaviors. The brain, by prioritizing behaviors and dynamically adjusting the flows of energy and nutrients, reduces costly errors and exploits more opportunities. Despite significant costs of computation, allostasis pays off and can now be recognized as a core principle of organismal design.

Ventromedial prefrontal cortex connectivity during and after psychological stress in women

The ventromedial prefrontal cortex (vmPFC) integrates sensory, affective, memory-related, and social information from diverse brain systems to coordinate behavioral and peripheral physiological responses according to contextual demands that are appraised as stressful. However, the functionality of the vmPFC during stressful experiences is not fully understood. Among 40 female participants, the present study evaluated (a) functional connectivity of the vmPFC during exposure to and recovery following an acute psychological stressor, (b) associations among vmPFC functional connectivity, heart rate, and subjective reports of stress across individuals, and (c) whether patterns of vmPFC functional connectivity were associated with distributed brain networks. Results showed that psychological stress increased vmPFC functional connectivity with individual brain areas implicated in stressor processing (e.g., insula, amygdala, anterior cingulate cortex) and decreased connectivity with the posterior cingulate cortex and thalamus. There were no statistical differences in vmPFC connectivity to individual brain areas during recovery, as compared with baseline. Spatial similarity analyses revealed stressor-evoked increased connectivity of the vmPFC with the so-called dorsal attention, ventral attention, and frontoparietal networks, as well as decreased connectivity with the default mode network. During recovery, vmPFC connectivity increased with the frontoparietal network. Finally, individual differences in heart rate and perceived stress were associated with vmPFC connectivity to the ventral attention, frontoparietal, and default mode networks. Psychological stress appears to alter network-level functional connectivity of the vmPFC in a manner that further relates to individual differences in stressor-evoked cardiovascular and affective reactivity.

Autonomic correlates of lifetime suicidal thoughts and behaviors among adolescents with a history of depression

Suicidal thoughts and behaviors (STBs) have been associated with emotion dysregulation and atypical responses to affective and stressful stimuli. To investigate the psychophysiology involved, we measured changes in respiratory sinus arrhythmia (RSA) and cardiac pre-ejection period (PEP; indexing parasympathetic and sympathetic functioning, respectively) in response to stressful- and sadness-eliciting laboratory probes. Our sample included adolescents with a history of depression and STBs (n = 177), adolescents with a history of depression but no history of STBs (n = 47), and healthy controls (n = 175). The outcome of interest was the most severe form of clinician-rated STBs across the subject's lifetime. In partial support of our hypotheses, during the stressful task, adolescents with a history of depression and STBs did not evidence the RSA decrease that was exhibited by controls and displayed greater PEP shortening compared to ever-depressed adolescents with no lifetime STBs. No group differences were found in either RSA or PEP reactivity to the sadness-eliciting stimulus. As expected, severity of STBs was positively correlated with the extent of PEP shortening during the stressful task. The results suggest that adolescents with a history of depression and STBs experience blunted parasympathetic responses to stress along with compensatory efforts. Our findings contribute to a better understanding of STBs among youths and underscore that future studies should examine physiological risk factors for these psychopathological outcomes.

Resonance-Paced Breathing Alters Neural Response to Visual Cues: Proof-of-Concept for a Neuroscience-Informed Adjunct to Addiction Treatments

Conscious attempts to regulate alcohol and drug use are often undermined by automatic attention and arousal processes that are activated in the context of salient cues. Response to these cues involves body and brain signals that are linked via dynamic feedback loops, yet no studies have targeted the cardiovascular system as a potential conduit to alter automatic neural processes that maintain cue salience. This proof-of-concept study examined within-person changes in neural response to parallel but unique sets of visual alcohol-related cues at two points in time: prior to versus following a brief behavioral intervention. The active intervention was resonance breathing, a rhythmical breathing task paced at 0.1 Hz (6 breaths per minute) that helps normalize neurocardiac feedback. The control intervention was a low-demand cognitive task. Functional magnetic resonance imaging (fMRI) was used to assess changes in brain response to the cues presented before (A1) and after (A2) the intervention in 41 emerging adult men and women with varying drinking behaviors. The resonance breathing group exhibited significantly less activation to A2 cues compared with A1 cues in left inferior and superior lateral occipital cortices, right inferior lateral occipital cortex, bilateral occipital pole, and temporal occipital fusiform cortices. This group also showed significantly greater activation to A2 cues compared with A1 cues in medial prefrontal, anterior and posterior cingulate, and precuneus cortices, paracingulate, and lingual gyri. The control group showed no significant changes. Thus, following resonance breathing, activation in brain regions involved in visual processing of cues was reduced, while activation in brain areas implicated in behavioral control, internally directed cognition, and brain-body integration was increased. These findings provide preliminary evidence that manipulation of the cardiovascular system with resonance breathing alters neural activation in a manner theoretically consistent with a dampening of automatic sensory input and strengthening of higher-level cognitive processing.

Taking rejection to heart: Associations between blood pressure and sensitivity to social pain

A reliable finding from the physical pain literature is that individuals with higher resting (i.e., tonic) blood pressure experience relatively less pain in response to nociceptive stimuli. Converging lines of evidence suggest that biological factors that influence the experience of physical pain may also relate to social pain. An open question, however, is whether higher blood pressure per se is a biological factor associated with lower sensitivity to social pain. This possible association was tested in three studies. Consistent with prior findings on physical pain, higher resting blood pressure was associated with lower self-reported sensitivity to social pain across individuals (Study 1 r = -.303, Study 2 r = -.262, -.246), even after adjusting for confounding factors related to blood pressure (Study 3 r = -.222). Findings suggest a previously unknown biological correlate of sensitivity to social pain, providing further evidence for possible shared substrates for physical and social pain.

Increased stressor-evoked cardiovascular reactivity is associated with reduced amygdala and hippocampus volume

Exaggerated cardiovascular reactivity to acute psychological stress is associated with an increased risk of developing cardiovascular disease. The amygdala and hippocampus have been implicated in centrally mediating stressor-evoked cardiovascular reactivity. However, little is known about the associations of amygdala and hippocampus morphology with stressor-evoked cardiovascular reactivity. Forty (M_age = 19.05, SD = 0.22 years) healthy young women completed two separate testing sessions. Session 1 assessed multiple parameters of cardiovascular physiology at rest and during a validated psychological stress task (Paced Auditory Serial Addition Test), using electrocardiography, Doppler echocardiography, and blood pressure monitoring. In Session 2, 1 year later, structural MRI was conducted. Brain structural volumes were computed using automated segmentation methods. Regression analyses, following Benjamini-Hochberg correction, showed that greater heart rate and cardiac output reactivity were associated with reduced amygdala and hippocampus gray matter volume. Systolic blood pressure reactivity was associated with reduced hippocampus volume. In contrast, no associations between diastolic blood pressure, mean arterial blood pressure, stroke volume, or total peripheral resistance reactivity with amygdala or hippocampus volumes were apparent. Comparison analyses examining insula volume found no significant associations. Some indicators of greater stressor-evoked cardiovascular reactivity associate with reduced amygdala and hippocampus gray matter volume, but the mechanisms of this association warrant further study.