Heterogeneity in neuroendocrine and immune responses to brief psychological stressors as a function of autonomic cardiac activation

Loneliness during the post-confinement period: The significance of social living conditions for stress biomarkers and memory

In the aftermath of the COVID-19 lockdown, concerns about the impact of loneliness and reduced social interactions on mental health have arisen. This study explored the repercussions of post-lockdown social restrictions across psychological (loneliness, perceived stress, and depressive symptoms), biological (hair cortisol and cardiovascular activity), and cognitive dimensions (subjective memory complaints and working, declarative, and prospective memory), with a specific emphasis on perceived loneliness and the living situation. The study included 45 students: 23 (mean age = 25.69 years) in the Alone Group (AG), who experienced significant family changes and international relocation, and 22 (mean age = 25.50 years) in the Not Alone Group (NAG), who maintained their nuclear family and did not move from their home country. We assessed heart rate variability (HRV) before, during, and after immediate memory evaluations using time-domain (the square root of the mean, RMSSD) measures. The analysis revealed no significant group differences in telematic contact with family and friends, perceived stress, or depression. However, the AG participants reported fewer face-to-face interactions and greater perceived loneliness compared to the NAG. Additionally, the AG group exhibited slightly higher hair cortisol levels and worse working memory (WM) and prospective memory (PM) performance. Importantly, no significant associations were observed between memory outcomes and stress biomarkers. However, a significant interaction effect of loneliness in the relationship between hair cortisol levels and PM was found. That is, hair cortisol concentrations were negatively related to PM when participants perceived high and moderate loneliness. This interaction was absent in the working and declarative memory domains. In summary, these findings underscore the intricate interplay between loneliness, cortisol, and memory, emphasizing the need for comprehensive research on the complex mechanisms governing these multifaceted relationships.

Doing it all: Effects of Family Responsibilities and Marital Relationship Quality on Mothers' Ambulatory Blood Pressure

BACKGROUND

The shared provider responsibility between married couples does not translate to equally shared division of childcare (CC) and household labor. While some marriages contain highly positive aspects, marriages may also simultaneously contain both positive and negative aspects. The negativity in these relationships can negate the positivity and could potentially lead to the detriment of mothers' health.

PURPOSE

We examined mothers' ambulatory blood pressure (ABP) associated with their marital relationship quality and perceived equity with her spouse on CC and household tasks.

METHODS

We investigate these associations using a mixed multilevel model analysis on a sample of 224 mothers in heterosexual marriages, all of whom had children under the age of 18 years currently living in the home.

RESULTS

Mothers' perception of equity in the division of CC responsibilities contributed to lower ABP. Additionally, mothers in supportive marital relationships (low negativity and high positivity) had lower ABP than those in ambivalent relationships (both high negativity and positivity). There was a crossover interaction such that the effect of relationship quality on ABP was moderated by the perception of equity in the division of CC. For mothers who report doing all the CC, they had lower ABP if they had a supportive marital relationship compared with mothers in ambivalent relationships. Whereas mothers who report more equity in CC and have a supportive relationship have higher ABP compared with mothers in ambivalent relationships.

CONCLUSIONS

This study has implications related to dynamics within marital relationships. These results demonstrate important relational influences on mothers' ABP.

Adolescent caregiving success as a predictor of social functioning from ages 13 to 33

Adolescent success providing satisfying support in response to a close friend's call in a caregiving task was examined as a potentially fundamental developmental competence likely to predict future social functioning, adult caregiving security, and physical health. Adolescents (86 males, 98 females; 58% White, 29% African American, 8% mixed race/ethnicity, 5% other) were followed from ages 13 to 33 (1998-2021) using multiple methods and reporters. Early caregiving success was found to predict greater self- and partner-reported caregiving security, lower negativity in adult relationships, and higher adult vagal tone. Results are interpreted as advancing our understanding beyond simply recognizing that adolescent friendships have long-term import, to now identifying specific capacities within friendships that are linked to longer-term outcomes.

Social Regulation of the Neural Threat Response Predicts Subsequent Markers of Physical Health

OBJECTIVE

Social support has been linked to a vast range of beneficial health outcomes. However, the physiological mechanisms of social support are not well characterized. Drawing on functional magnetic resonance imaging and health-related outcome data, this study aimed to understand how neural measures of "yielding"-the reduction of brain activity during social support-moderate the link between social support and health.

METHODS

We used a data set where 78 participants around the age of 24 years were exposed to the threat of shock when holding the hand of a partner. At ages 28 to 30 years, participants returned for a health visit where inflammatory activity and heart rate variability were recorded.

RESULTS

Findings showed a significant interaction between dorsal anterior cingulate cortex-related yielding and perceived social support on C-reactive protein levels ( β = -0.95, SE = 0.42, z = -2.24, p = .025, 95% confidence interval = -1.77 to -0.12). We also found a significant interaction between hypothalamus-related yielding and perceived social support on baseline heart rate variability ( β = 0.51, SE = 0.23, z = 2.19, p = .028, 95% confidence interval = 0.05 to 0.97).

CONCLUSIONS

Greater perceived social support was associated with lower C-reactive protein levels and greater baseline heart rate variability among individuals who were more likely to yield to social support in the dorsal anterior cingulate cortex and hypothalamus years earlier. The current study highlights the construct of yielding in the link between social support and physical health.

Application of attentional bias modification to reduce attentional bias and emotional reactivity to stress in mildly depressed individuals

This study aims to verify the effectiveness of attentional bias modification (ABM) in reducing attentional bias related to depression, particularly in the later stages of attention as a pattern of difficulty in disengagement from depression-relevant stimuli, and to assess its effects on emotional reactivity to stress. A total of 78 participants were separated into four groups based on their levels of depression (minimal and mild) and the types of ABM. The positive ABM (pABM) trained participants to disengage their attention from depression-relevant stimuli and directed their attention toward more positive stimuli, whereas the neutral ABM (nABM) was designed to have no effect. The participants underwent a free-viewing task by eye tracker both before and after ABM to observe changes in attentional bias. Subsequently, they reported their emotional response after a stress-inducing task. The group of mildly depressed participants receiving pABM showed significantly less attention to depression-relevant negative affective stimuli and reported significantly decreased negative emotional reactivity to stress compared to the other groups. pABM had an effect on decreasing difficulty in disengaging from depression-relevant negative affective words (DW). However, it did not increase the dwell time on positive affective words (PW) in the current study. This might be due to the short duration of the application of ABM. The current study conducted ABM twice in 1 day, and this might not be enough to increase the dwell time on PA. This study verified that the ABM effectively decreased the attentional bias of depression and its relevant symptom, emotional reactivity to stress.

Social Support: The Effect on Nocturnal Blood Pressure Dipping

Social support has long been associated with cardiovascular disease risk assessed with blood pressure (BP). BP exhibits a circadian rhythm in which BP should dip between 10 and 15% overnight. Blunted nocturnal dipping (non-dipping) is a predictor of cardiovascular morbidity and mortality independent of clinical BP and is a better predictor of cardiovascular disease risk than either daytime or nighttime BP. However, it is often examined in hypertensive individuals and less often in normotensive individuals. Those under age 50 are at increased risk for having lower social support. This study examined social support and nocturnal dipping in normotensive individuals under age 50 using ambulatory blood pressure monitoring (ABP). ABP was collected in 179 participants throughout a 24-h period. Participants completed the Interpersonal Support Evaluation List, which assesses perceived levels of social support in one's network. Participants with low levels of social support demonstrated blunted dipping. This effect was moderated by sex, with women showing greater benefit from their social support. These findings demonstrate the impact social support can have on cardiovascular health, exhibited through blunted dipping, and are particularly important as the study was conducted in normotensive individuals who are less likely to have high levels of social support.

Getting under the skin: long-term links of adolescent peer relationship difficulties to adult vagal tone

Understanding whether and how the absence of positive relationships may predict longer-term physical health outcomes is central to building a working conceptual model of the interplay of social and physical development across the lifespan. This study sought to examine the extent to which difficulties establishing positive social relationships from adolescence onward serve as long-term predictors of low adult vagal tone, which in turn has been linked to numerous long-term health problems. A diverse community sample of 141 individuals was followed via multiple methods and reporters from age 13 to 29. Across this span, social relationship quality was assessed via close friend and peer reports, observations of romantic interactions, and self-reported romantic relationship satisfaction. A range of potential personality and functional covariates was also considered. Vagal tone while at rest was assessed at age 29. Adult vagal tone was predicted across periods as long as 16 years by: adolescents' difficulty establishing themselves as desirable companions among peers; early adults' inability to establish strong close friendships; and lack of warmth in romantic relationships as an adult. Poor early adult friendship quality statistically mediated the link from adolescent peer difficulties to adult vagal tone. A range of potential confounding factors was examined but was not linked to vagal tone. Within the limits of the correlational design of the study, robust connections between adult vagal tone and social relationship quality from adolescence onward suggest at least a possible mechanism by which relationship difficulties may get 'under the skin' to influence future physiological functioning.

Cardiovascular reactivity, stress, and personal emotional salience: Choose your tasks carefully

Both greater cardiovascular reactivity and lesser reactivity ("blunting") to laboratory stressors are linked to poor health outcomes, including among people who have a history of traumatic experiences. In a sample of recently separated and divorced adults (N = 96), this study examined whether differences in cardiovascular reactivity might be explained by differences in the personal emotional salience of the tasks and trauma history. Participants were assessed for trauma history, current distress related to their marital dissolution, and cardiovascular reactivity during two tasks, a serial subtraction math stressor task and a divorce-recall task. Participants with a greater trauma history evidenced less blood pressure reactivity to the serial subtraction task (a low personal emotional salience task) when compared to participants with less trauma history. In contrast, participants with a greater trauma history evidenced higher blood pressure reactivity to the divorce-recall task, but only if they also reported more divorce-related distress (high personal emotional salience). These associations were not significant for heart rate reactivity. Among people with a history of more traumatic experiences, a task with low personal salience was associated with a lower blood pressure response, whereas a task with higher personal emotional salience was associated with a higher blood pressure response. Future studies examining cardiovascular reactivity would benefit from determining the personal emotional salience of tasks, particularly for groups that have experienced stressful life events or trauma.

Sympathetic involvement in time-constrained sequential foraging

Appraising sequential offers relative to an unknown future opportunity and a time cost requires an optimization policy that draws on a learned estimate of an environment’s richness. Converging evidence points to a learning asymmetry, whereby estimates of this richness update with a bias toward integrating positive information. We replicate this bias in a sequential foraging (prey selection) task and probe associated activation within the sympathetic branch of the autonomic system, using trial-by-trial measures of simultaneously recorded cardiac autonomic physiology. We reveal a unique adaptive role for the sympathetic branch in learning. It was specifically associated with adaptation to a deteriorating environment: it correlated with both the rate of negative information integration in belief estimates and downward changes in moment-to-moment environmental richness, and was predictive of optimal performance on the task. The findings are consistent with a framework whereby autonomic function supports the learning demands of prey selection.

The self in context: brain systems linking mental and physical health

Increasing evidence suggests that mental health and physical health are linked by neural systems that jointly regulate somatic physiology and high-level cognition. Key systems include the ventromedial prefrontal cortex and the related default-mode network. These systems help to construct models of the 'self-in-context', compressing information across time and sensory modalities into conceptions of the underlying causes of experience. Self-in-context models endow events with personal meaning and allow predictive control over behaviour and peripheral physiology, including autonomic, neuroendocrine and immune function. They guide learning from experience and the formation of narratives about the self and one's world. Disorders of mental and physical health, especially those with high co-occurrence and convergent alterations in the functionality of the ventromedial prefrontal cortex and the default-mode network, could benefit from interventions focused on understanding and shaping mindsets and beliefs about the self, illness and treatment.

Associations between multisystem stress reactivity and peer nominated aggression in early childhood vary by sex

There is emerging evidence that the development of problematic aggression in childhood may be associated with specific physiological stress response patterns, with both biological overactivation and underactivation implicated. This study tested associations between sex-specific patterns of stress responses across the sympathetic nervous system (SNS) and hypothalamic-pituitary-adrenal (HPA) axis and peer nominations of aggression among 271 kindergarten children (Mean age = 5.32 years; 52% Female; 44% White). Upon entry to kindergarten, children participated in a multidomain standardized stress paradigm. Changes in pre-ejection period (PEP) and salivary cortisol were assessed. On a separate day, children provided peer ratings of physical and relational aggression in a standardized interview. As expected, there was a significant three-way interaction between PEP, cortisol reactivity, and sex, but only for physical aggression. Among boys, cortisol reactivity was positively associated with physical aggression only for those with higher SNS reactivity. Findings suggest that for boys, asymmetrical and symmetrical HPA/SNS reactivity may be associated with lower and higher risk for peer-directed physical aggression, respectively. Understanding the complex associations between multisystem physiology, child sex and peer-directed aggression in early childhood may offer insight into individual differences underlying the emergence of behavioral dysregulation in early peer contexts.

Towards an understanding of neurophysiological self-regulation in early childhood: A heuristic and a new approach

Self-regulation in early childhood encompasses both "top down," volitional processes, as well as the "bottom up" activity of three neurophysiological systems: the parasympathetic nervous system (PNS), the sympathetic nervous system (SNS), and the hypothalamic-pituitary-adrenal (HPA) axis. In this paper we briefly review the structure, function, and early development of each of these systems and then explain why neurophysiological self-regulation is most accurately defined as a function of their joint activity. We note that while there are a number of predictive models that employ this definition, the field would benefit from a straightforward heuristic and aligned methods of visualization and analysis. We then present one such heuristic, which we call neurophysiological space, and outline how it may facilitate a new, collaborative approach to building a better understanding of self-regulation in early childhood. We conclude with a presentation of early education as one setting in which our heuristic and methods could be applied.

The developmental precursors of blunted cardiovascular responses to stress

Blunted cardiovascular responses to stress have been associated with both mental and physical health concerns. This multi-method, longitudinal study examined the role of chronic social-developmental stress from adolescence onward as a precursor to these blunted stress responses. Using a diverse community sample of 184 adolescents followed from age 13 to 29 along with friends and romantic partners, this study found that high levels of parental psychological control at age 13 directly predicted a blunted heart rate response and indirectly predicted blunted respiratory sinus arrhythmia (RSA) reactivity under stress. Heart rate effects were mediated via indicators of a developing passive response style, including observational measures of withdrawal during conflict with friends and romantic partners, social disengagement, and coping with stressors by using denial. RSA effects were mediated via withdrawal during conflict with romantic partners and coping by using denial. The current findings are interpreted as suggesting a mechanism by which a key social/developmental stressor in adolescence may alter relational and ultimately physiological patterns of stress responding into adulthood.

Self-Rated Health and Age-Related Differences in Ambulatory Blood Pressure: The Mediating Role of Behavioral and Affective Factors

OBJECTIVE

Despite the well-established association between self-rated health (SRH) and health, little is known about the potential psychobiological mechanisms responsible for such links and if these associations differ by age. The main goals of this study were to investigate the links between SRH and ambulatory blood pressure (ABP), if age moderated the risk, and the health behavior/affective mechanisms responsible for such links.

METHODS

A total of 188 men and women (94 married couples; ages, 18-63 years) completed a standard measure of SRH and a 1-day ABP assessment. Multilevel models were run to examine whether SRH was associated with daily ABP and whether these links were moderated by age. The Monte Carlo method was used to construct confidence intervals for mediation analyses.

RESULTS

Results indicated that poor SRH was associated with higher ambulatory systolic blood pressure (SBP; b = 3.14, SE = 0.68, p < .001) and diastolic blood pressure (DBP; b = 1.34, SE = 0.43, p = .002) levels. Age also moderated the links between SRH and ambulatory SBP (b = 0.19, SE = 0.08, p = .011) and DBP (b = 0.14, SE = 0.05, p = .004), with links being stronger in relatively older individuals. However, only daily life negative affect significantly mediated the age by SRH interaction for both ambulatory SBP and DBP.

CONCLUSIONS

These results highlight the potential psychobiological mechanisms linking SRH to longer-term health outcomes. Such work can inform basic theory in the area as well as intervention approaches that target such pathways.

Ambivalence in the Early Years of Marriage: Impact on Ambulatory Blood Pressure and Relationship Processes

BACKGROUND

Marriage is associated with lower cardiovascular morbidity and mortality, but quality matters. Marriages characterized by ambivalent behaviors (containing both highly positive and highly negative behaviors concurrently) may not confer the same cardiovascular benefits as characterized by purely positive behavior. Ambivalence is assumed to take time to develop but couples in the early years of marriage may already exhibit ambivalent behaviors and thus be at increased risk for future cardiovascular events.

PURPOSE

The purpose of this study was to determine the frequency of spouse and own ambivalent behavior, the impact on interpersonal (i.e., responsiveness, disclosure, affective interactions) processes, and ambulatory blood pressure (ABP) in individuals in the early years of marriage.

METHODS

In 84 young married couples, objective and subjective ambivalence, interpersonal functioning, and ABP over a 24-hr period were assessed.

RESULTS

As predicted, ambivalence developed early in marriage. Regarding interpersonal processes, spousal and own objective ambivalent behavior was associated with lower spousal responsiveness (p < .01), disclosure (p < .05), and more negative (p < .03) and less positive interactions (p < .001). Physiologically, ambivalent spousal behavior was associated with higher systolic blood pressure (p = .02) and higher diastolic blood pressure (p = .04). Measures of subjective ambivalence were congruent.

CONCLUSIONS

Early marriages already contain ambivalent behavior; in such cases, individuals may not receive the cardiovascular protection of a supportive marriage.

The impact of informal cancer caregiving: A literature review on psychophysiological studies

Caregiving can be experienced as a stressful process, which can cause psychological and physical consequences. The combination of prolonged stress and the physical demands of caregiving may impair the physiological functioning of caregivers and increase the risk of health problems creating considerable stress in the life of caregivers regarding emotional, physical, social and financial areas. This literature review explored studies that used measures of the autonomic nervous system in caregivers of oncology patients such as electrodermal and cardiovascular (re)activity. The results revealed that caregivers had elevated stress levels and a serious autonomic imbalance that may, in the long term, trigger negative health consequences such as infectious diseases, cancer progression, cardiovascular disease and even premature death. The results showed the need to carry out preventive strategies in this population, in order to improve the autonomic profile of caregivers of cancer patients.

Effect of gender-related depression on heart rate variability during an autonomic nervous test

Patients with depression have lower heart rate variability (HRV) compared with controls. However, studies have indicated HRV difference between male and female controls. The gender effect might be interactive with the depression effect on the HRV, resulting in a low accuracy of recognising the patients with depression from the controls. Our study explores the effect of gender-related depression on HRV. Four ANS tests including resting, deep breathing, Valsalva, and orthostatic test are employed as stimuli. HRV were collected from 182 subjects comprising 91 depressive patients (33 females/58 males) and 91 controls (33 females/58 males) in the four tests. Time and frequency domains and nonlinear parameters are employed to quantify HRV. Two-way ANOVA is applied to evaluate the effect of gender-related depression. Most HRV parameters of the patients significantly differ from those of the controls, but some parameters indicate different depression effect between the males and females in the deep breathing and Valsalva test. Some HRV parameters illustrate significant difference between the male and female controls. Therefore, the effect of depression on HRV of each gender should be investigated.

Association between changes in heart rate variability during the anticipation of a stressful situation and the stress-induced cortisol response

Vagal activity - reflecting the activation of stress regulatory mechanisms and prefrontal cortex activation - is thought to play an inhibitory role in the regulation of the hypothalamus-pituitary-adrenal axis. However, most studies investigating the association between stress-induced changes in heart rate variability (HRV, an index of cardiac vagal tone) and cortisol have shown a non-significant relationship. It has been proposed that physiological changes observed during anticipation of a stressor allow individuals to make behavioral, cognitive, and physiological adjustments that are necessary to deal with the upcoming actual stressor. In this study, in a large sample of 171 healthy adults (96 men and 75 women; mean age = 29.98, SD = 11.07), we investigated whether the cortisol response to a laboratory-based stress task was related to anticipation-induced or stress task-induced changes in HRV. As expected, regression analyses showed that a larger decrease in HRV during the anticipation of a stress task was related to higher stress task-induced cortisol increase, but not cortisol recovery. In line with prior research, the stress task-induced change in HRV was not significantly related to cortisol increase or recovery. Our results show for the first time that anticipatory HRV (reflecting differences in stress regulation and prefrontal activity before the encounter with the stressor) is important to understand the stress-induced cortisol increase.

During stress, heart rate variability moderates the impact of childhood adversity in women with breast cancer

Childhood adversity has long-lasting neuro-biological effects that can manifest as exaggerated stress responsivity to environmental challenge. These manifestations include a dysregulated hypothalamic-pituitary-adrenocortical (HPA) axis as well as increased levels of inflammatory mediators in response to stress. In this investigation, vagal parasympathetic activity was assessed for its capacity to moderate the relationship between childhood adversity and stress responsivity (cortisol and inflammation) during an acute laboratory challenge (Trier Social Stress Test-TSST). Thirty women recently diagnosed with breast cancer underwent the TSST during which their heart rate was recorded and saliva samples collected for measurement of cortisol and the proinflammatory cytokine, IL-6. Vagal activity during the TSST was calculated as the high-frequency (HF) component of heart rate variability (HRV). Vagal activity during the TSST moderated the effect of childhood adversity on both the cortisol and the IL-6 response. Women who had lower vagal stress-reactivity during the TSST and reported greater childhood adversity showed a larger rise in cortisol and IL-6 when compared to women with lower childhood adversity. The findings demonstrate that women with exposure to childhood adversity and low vagal stress-reactivity (reduced parasympathetic activity) exhibit an elevated stress response characterized by greater cortisol and proinflammatory cytokine release. Inflammatory burden and HPA dysregulation subsequent to stress may impair cancer control.

Type 1 long QT syndrome and psychological stress in a laboratory setting

Trait-like sensitivity to stress in long QT syndrome patients has been documented previously. In addition, mental stress has been associated with symptomatic status of long QT syndrome. We examined whether the symptomatic type 1 long QT syndrome patients would be more sensitive to mental stress compared to asymptomatic patients and whether there would be differences in task-related physiological stress reactions between type 1 long QT syndrome patients and healthy individuals. The study population consisted of 21 symptomatic and 23 asymptomatic molecularly defined KCNQ1 mutation carriers, their 32 non-carrier relatives and 46 non-related healthy controls, with mean ages of 37, 39, 35 and 23 years, respectively. Electrocardiography was utilised to calculate inter-beat interval and high frequency and low frequency heart rate variability. Blood pressure was measured and mean arterial pressure and pulse pressure were calculated. Stress was induced using three different tasks: mental arithmetic, reaction time and public speech. Stress responses of symptomatic and asymptomatic type 1 long QT syndrome patients were not statistically different in any of the stress tasks. Short-term physiological stress reactivity of symptomatic type 1 long QT syndrome patients appears to be normal and does not enhance the risk assessment of asymptomatic mutation carriers.

Preliminary evidence of attenuated blood pressure reactivity to acute stress in adults following a recent marital separation

OBJECTIVE

This study explores cardiovascular reactivity during an acute-stress task in a sample of recently separated adults.

DESIGN

In a cross-sectional design, we examined the association between adults' subjective separation-related distress and changes in heart rate and blood pressure across the acute-stress laboratory paradigm in a sample of 133 (n = 49 men) recently separated adults.

MAIN OUTCOME MEASURES

Heart rate (HR) and Blood pressure (BP) were recorded across a resting baseline period, a math stressor task, and a recovery period.

RESULTS

Multilevel analyses revealed that adults who reported greater separation-related distress exhibited higher initial BP and a slower linear increase in BP across the study period. In addition, adults reporting greater separation-related distress evidenced significantly slower declines in diastolic blood pressure (DBP) following the acute-stress task. HR reactivity was not moderated by separation-related distress.

CONCLUSIONS

In recently separated adults, preliminary evidence suggests that the context of the stressors may reveal differential patterns of problematic reactivity (exaggerated or blunted responding). Greater emotional intrusion and hyperactivity symptoms may index increased risk for blunted cardiovascular reactivity to general stressors. This pattern of reactivity is consistent with models of allostatic load that emphasise the deleterious effect of hyporesponsivity to environmental demands.

Biological markers for anxiety disorders, OCD and PTSD: A consensus statement. Part II: Neurochemistry, neurophysiology and neurocognition

OBJECTIVE

Biomarkers are defined as anatomical, biochemical or physiological traits that are specific to certain disorders or syndromes. The objective of this paper is to summarise the current knowledge of biomarkers for anxiety disorders, obsessive-compulsive disorder (OCD) and posttraumatic stress disorder (PTSD).

METHODS

Findings in biomarker research were reviewed by a task force of international experts in the field, consisting of members of the World Federation of Societies for Biological Psychiatry Task Force on Biological Markers and of the European College of Neuropsychopharmacology Anxiety Disorders Research Network.

RESULTS

The present article (Part II) summarises findings on potential biomarkers in neurochemistry (neurotransmitters such as serotonin, norepinephrine, dopamine or GABA, neuropeptides such as cholecystokinin, neurokinins, atrial natriuretic peptide, or oxytocin, the HPA axis, neurotrophic factors such as NGF and BDNF, immunology and CO2 hypersensitivity), neurophysiology (EEG, heart rate variability) and neurocognition. The accompanying paper (Part I) focuses on neuroimaging and genetics.

CONCLUSIONS

Although at present, none of the putative biomarkers is sufficient and specific as a diagnostic tool, an abundance of high quality research has accumulated that should improve our understanding of the neurobiological causes of anxiety disorders, OCD and PTSD.

The quality of social networks predicts age-related changes in cardiovascular reactivity to stress

Although existing life span models suggest that positivity in relationships should benefit the health of older adults, much less is known about how relationships that contain both positive and negative aspects (i.e., ambivalent ties) might influence age-associated cardiovascular risk. Given the increased interpersonal stress associated with ambivalent ties, the SAVI model would predict that older adults might be more negatively influenced given age-related changes in physiological flexibility. In this study, the quality of an individual's social network (i.e., supportive, ambivalent, aversive) was used to predict cardiovascular reactivity during laboratory stress across a 10-month follow-up period in 108 participants between the ages 30 to 70. Results revealed evidence that the number of ambivalent network ties predicted greater increases in diastolic blood pressure reactivity. Importantly, there was an Age × Ambivalent Ties interaction in which the number of ambivalent ties was related to greater increases in systolic blood pressure reactivity primarily in older adults. These data are discussed in terms of the health implications of social networks across the life span. (PsycINFO Database Record

Stress, the Autonomic Nervous System, and the Immune-kynurenine Pathway in the Etiology of Depression

The autonomic nervous system is one of the major neural pathways activated by stress. In situations that are often associated with chronic stress, such as major depressive disorder, the sympathetic nervous system can be continuously activated without the normal counteraction of the parasympathetic nervous system. As a result, the immune system can be activated with increased levels of pro-inflammatory cytokines. These inflammatory conditions have been repeatedly observed in depression. In the search for the mechanism by which the immune system might contribute to depression, the enhanced activity of indoleamine 2,3-dioxygenase by pro-inflammatory cytokines has been suggested to play an important role. Indoleamine 2,3-dioxygenase is the first enzyme in the kynurenine pathway that converts tryptophan to kynurenine. Elevated activity of this enzyme can cause imbalances in downstream kynurenine metabolites. This imbalance can induce neurotoxic changes in the brain and create a vulnerable glial-neuronal network, which may render the brain susceptible to depression. This review focuses on the interaction between stress, the autonomic nervous system and the immune system which can cause imbalances in the kynurenine pathway, which may ultimately lead to major depressive disorder.

Psychophysiological correlates of systemic inflammation in black and white men

Inflammation plays a critical role in the pathophysiology of cardiovascular disease (CVD) and levels of circulating inflammatory markers are associated with future CVD risk. However, the physiological mechanisms that control systemic levels of circulating inflammatory markers are not well understood. Here, we explore possible autonomic nervous system mechanisms by testing whether resting and stressor-evoked cardiovascular responses are associated with two markers of systemic inflammation: interleukin (IL)-6 and C-reactive protein (CRP). Subjects were 159 black and 129 white men (M=33.0years) who completed a laboratory protocol including an anger recall speech task. Electrocardiography and impedance cardiography data were collected during a resting baseline, the speech task, and a final recovery period. Hierarchical regressions tested whether resting or stressor-evoked levels of heart rate (HR), high-frequency heart rate variability (HF-HRV), pre-ejection period (PEP), and pulse transit time (PTT) were associated with CRP or IL-6. Higher resting HR was associated with higher CRP (β=0.19, p=0.003) and IL-6 (β=0.13, p<0.05). Similarly, shorter resting PTT was associated with higher CRP (β=-0.21, p<0.001) and IL-6 (β=-0.14, p=0.02). In addition, greater stressor-evoked decreases in HF-HRV were associated with higher CRP (β=-0.14, p=0.01). Associations were independent of age, race, body mass index (BMI), smoking behavior, and socioeconomic status. Resting HF-HRV and PEP were also associated with CRP and IL-6, but associations were not significant after controlling for BMI and smoking behavior. These findings indicate that resting HR and PTT, as well stressor-evoked HF-HRV reactivity, are associated with systemic inflammation. Our results suggest that both tonic and stressor-evoked sympathetic and parasympathetic nervous system activity may contribute to regulation of systemic inflammation.

Contributions of Psychophysiology to Research on Adult Attachment: Review and Recommendations

Despite the increasing use of psychophysiological measures to investigate social and interpersonal phenomena, few studies of adult romantic attachment have taken advantage of this approach. In this article I argue for a biologically-specific, theory-based integration of psychophysiological measures into adult attachment research. This approach would help elucidate the normative psychobiological properties of the attachment system, which have received little study in humans. Specifically, it would allow researchers to test targeted hypotheses regarding affect and arousal regulation in attachment relationships. I provide a general introduction to 2 biological systems that hold particular promise for adult attachment research: the parasympathetic branch of the autonomic nervous system and the hypothalamic-pituitary-adrenocortical axis of the endocrine system. I highlight the relevance of these systems for attachment phenomena and review findings from selected social psychophysiological research. I conclude by outlining a tentative theoretical model of the psychobiology of adult attachment and identifying specific directions for future research.

Heart Rate Variability Moderates the Association Between Separation-Related Psychological Distress and Blood Pressure Reactivity Over Time

Divorce is a stressor associated with long-term health risk, though the mechanisms of this effect are poorly understood. Cardiovascular reactivity is one biological pathway implicated as a predictor of poor long-term health after divorce. A sample of recently separated and divorced adults (N = 138) was assessed over an average of 7.5 months to explore whether individual differences in heart rate variability-assessed by respiratory sinus arrhythmia-operate in combination with subjective reports of separation-related distress to predict prospective changes in cardiovascular reactivity, as indexed by blood pressure reactivity. Participants with low resting respiratory sinus arrhythmia at baseline showed no association between divorce-related distress and later blood pressure reactivity, whereas participants with high respiratory sinus arrhythmia showed a positive association. In addition, within-person variation in respiratory sinus arrhythmia and between-persons variation in separation-related distress interacted to predict blood pressure reactivity at each laboratory visit. Individual differences in heart rate variability and subjective distress operate together to predict cardiovascular reactivity and may explain some of the long-term health risk associated with divorce.

Inter-relation between autonomic and HPA axis activity in children and adolescents

Stress research in youth typically considers either the autonomic nervous system or HPA axis. However, these systems are highly coordinated and physically interconnected. We examined whether the inter-relation between cardio-autonomic and HPA axis measures was better associated with perceived stress than their singular associations. Children and adolescents (N=201) collected saliva samples to measure cortisol (AUCAG, AUCI, maximum), wore an electrocardiogram monitor for 24h to derive heart rate variability (HRV; LF, HF, LF/HF ratio), and completed the Perceived Stress Scale. The interaction between sympathovagal modulation (LF, LF/HF ratio) and cortisol awakening response (AUCAG, AUCI, maximum) explained significantly greater variance in perceived stress than either stress system alone. Higher sympathovagal modulation combined with higher cortisol awakening response was associated with greater perceived stress. Findings suggest that the inter-relation between cardio-autonomic and HPA axis activity may advance our understanding of how stress impacts health.

The quality of spouses' social networks contributes to each other's cardiovascular risk

OBJECTIVES

Although the quality of one's own social relationships has been related to cardiovascular morbidity and mortality, whether a partner's social network quality can similarly influence one's cardiovascular risk is unknown. In this study we tested whether the quality of a partner's social networks influenced one's own ambulatory blood pressure (ABP).

METHODS

The quality of 94 couples' social networks was determined using a comprehensive model of relationships that separates out social ties that are sources of positivity(supportive), negativity (aversive), and both positivity and negativity (ambivalent). We then utilized statistical models (actor-partner analyses) that allowed us to separate out the links between one's own social network quality on ABP (actor influences), a partner's social network quality on ABP (partner influences), and a couple's network quality combined on ABP (actor X partner interactions).

RESULTS

Independent of one's own relationship quality, results showed that an individual's ABP was lower if their spouse had more supportive ties, and higher if a spouse had more aversive and ambivalent ties. In addition, couples' networks in combination were associated with higher ABP but only if both had a low number of supportive ties, or a high number of aversive or ambivalent ties.

CONCLUSIONS

These data suggest that the social ties of those we have close relationships with may influence our cardiovascular risk and opens new opportunities to capitalize on untapped social resources or to mitigate hidden sources of social strain.

Family adversity and autonomic reactivity association with immune changes in HIV-affected school children

OBJECTIVE

To explore whether primary school entry is associated with changes in immune system parameters in HIV-affected children. HIV-affected children are vulnerable to psychosocial stressors, regardless of their own HIV serological status.

METHODS

Data from 38 HIV-positive and 29 HIV-negative children born to seropositive women were obtained. Measures included family adversity questionnaires, autonomic nervous system (ANS) reactivity, and enumerative and functional changes in peripheral blood immune parameters.

RESULTS

In comparison with children who were HIV-negative, children who were HIV-positive at baseline had fewer CD4(+) T lymphocytes (mean [M] = 916 versus 1206 cells/mm(3) × 10(3); F = 7.8, p = .007), more CD8(+) cells (M = 1046 versus 720 cells/mm(3) × 10(3); F = 7.98, p = .006), and diminished natural killer cell cytotoxicity (M = -0.29 versus 0.41; F = 8.87, p = .004). School entry was associated with changes in immune parameters, but HIV status was not associated with the magnitude of changes. Changes in immune parameters after school entry were associated with family stress and preschool entry ANS reactivity. Highly ANS reactive children had either the greatest increase in CD8(+) cells after school entry or the greatest decrease, depending on reported levels of family adversity (B = 215.35; t = 3.74, p < .001). Changes in functional immune assays were significantly associated with the interactions between HIV status and ANS reactivity.

CONCLUSIONS

These results suggest that autonomic reactivity is associated with increased immunological sensitivity to adverse or challenging social contexts among children affected by HIV.

Specific dimensions of perceived support and ambulatory blood pressure: which support functions appear most beneficial and for whom?

Perceived support has been related to lower cardiovascular morbidity and mortality. However, little is known about the specific functional components of support responsible for such links. We tested if emotional, informational, tangible, and belonging support predicted ambulatory blood pressure (ABP) and interpersonal interactions (e.g., responsiveness), and if such links were moderated by gender. In this study, 94 married couples underwent 12 h of ABP monitoring during daily life which included a night at home with their spouse. They completed a short-form of the interpersonal support evaluation list that provides information on total (global) support, as well as specific dimensions of support. Results revealed that global support scores did not predict ABP during daily life. However, separating out distinct support components revealed that emotional support was a significant predictor of lower ambulatory systolic and diastolic blood pressure, primarily for women. Finally, emotional support predicted greater partner responsiveness and self-disclosure, along with less perceived partner negativity although these results were not moderated by gender. These data are discussed in terms of the importance of considering specific support components and the contextual processes that might influence such links.

A randomized controlled trial of a self-guided, multimedia, stress management and resilience training program

BACKGROUND

Stress is a common and costly behavioral health issue. Technology-based behavioral health programs (e.g., computer or web-based programs) are effective for treating anxiety or depression. These programs increase availability of evidence-based interventions to individuals who are not able or willing to receive such in-person treatments. Stress management training has empirical support, but little data exists on its efficacy with stressed but healthy individuals, and there are no prior studies employing a self-guided, multimedia intervention. We conducted a randomized controlled trial of a self-guided, multimedia stress management and resilience training program (SMART-OP) with a stressed but healthy sample.

METHODS

Participants (N = 66) were randomized to SMART-OP or an attention control (AC) group that received marketed videos and published material on stress management. Participants were evaluated on self-report measures and Trier Social Stress Test (TSST) performance. Analyses were based on study completers (N = 59).

RESULTS

SMART-OP group reported significantly less stress, more perceived control over stress, and rated SMART-OP as significantly more useful than AC. During the TSST, the data suggests the SMART-OP group showed greater within-task α-amylase recovery at post-assessment.

CONCLUSIONS

SMART-OP is highly usable and is a more effective and useful stress management training program than an educational comparison.

Subliminal activation of social ties moderates cardiovascular reactivity during acute stress

OBJECTIVE

The quality of one's personal relationships has been reliably linked to important physical health outcomes, perhaps through the mechanism of physiological stress responses. Most studies of this mechanism have focused on whether more conscious interpersonal transactions influence cardiovascular reactivity. However, whether such relationships can be automatically activated in memory to influence physiological processes has not been determined. The primary aims of this study were to examine whether subliminal activation of relationships could influence health-relevant physiological processes and to examine this question in the context of a more general relationship model that incorporates both positive and negative dimensions.

METHOD

We randomly assigned participants to be subliminally primed with existing relationships that varied in their underlying positivity and negativity (i.e., indifferent, supportive, aversive, ambivalent). They then performed acute psychological stressors while cardiovascular and self-report measures were assessed.

RESULTS

Priming negative relationships was associated with greater threat, lower feelings of control, and higher diastolic blood pressure reactivity during stress. Moreover, priming relationships high in positivity and negativity (ambivalent ties) was associated with the highest heart rate reactivity and greatest respiratory sinus arrhythmia decreases during stress. Exploratory analyses during the priming task itself suggested that the effects of negative primes on biological measures were prevalent across tasks, whereas the links to ambivalent ties was specific to the subsequent stressor task.

CONCLUSIONS

These data highlight novel mechanisms by which social ties may impact cardiovascular health, and further suggest the importance of incorporating both positivity and negativity in the study of relationships and physical health.

Association between Cold Face Test-induced vagal inhibition and cortisol response to acute stress

Low vagal function is related to several disorders. One possible underlying mechanism linking the vagus nerve and disorders is the HPA axis. Thirty-three healthy male subjects participated in a stress task, while heart rate (HR), respiratory sinus arrhythmia (RSA), salivary cortisol, and mood were assessed. Vagal function was determined using baseline, stress-induced inhibition, and Cold Face Test (CFT)-induced stimulation. The stress task induced a significant increase in cortisol and HR, a decrease in RSA, and a worsening of mood. A linear regression model with the time from CFT onset until maximum bradycardia as the independent variable explained 17.9% of the total variance in cortisol in response to the stressor (mood: 36.5%). The results indicate that a faster CFT response is associated with reduced cortisol increase and enhanced mood after acute stress. Our data support an inverse relationship between vagal function and the HPA axis.

On the importance of knowing your partner's views: attitude familiarity is associated with better interpersonal functioning and lower ambulatory blood pressure in daily life

BACKGROUND

Relationships have been linked to significant physical health outcomes. However, little is known about the more specific processes that might be responsible for such links.

PURPOSE

The main aim of this study was to examine a previously unexplored and potentially important form of partner knowledge (i.e., attitude familiarity) on relationship processes and cardiovascular function.

METHODS

In this study, 47 married couples completed an attitude familiarity questionnaire and ambulatory assessments of daily spousal interactions and blood pressure.

RESULTS

Attitude familiarity was associated with better interpersonal functioning between spouses in daily life (e.g., greater partner responsiveness). Importantly, attitude familiarity was also related to lower overall ambulatory systolic blood pressure and diastolic blood pressure.

CONCLUSIONS

These data suggest that familiarity with a spouse's attitudes may be an important factor linking relationships to better interpersonal and physical health outcomes.

Provider and recipient factors that may moderate the effectiveness of received support: examining the effects of relationship quality and expectations for support on behavioral and cardiovascular reactions

Social relationships have been shown to predict decreased risk for morbidity and mortality. However, the more precise processes underlying these associations are in need of exploration. In this study, we examined important provider (relationship quality) and recipient-related (support expectations) factors that might influence the effectiveness of receiving support on cardiovascular reactivity (CVR). Participants discussed a stressful event with either a supportive or ambivalent friend, and were either given instructions that included an explicit expectation of support provision or no expectation during the task. Behavioral coding revealed fewer emotionally supportive behaviors and marginally more negative behaviors from ambivalent friends. Receiving support from an ambivalent friend was also associated with higher systolic blood pressure reactivity compared to a supportive friend, but had no effects on diastolic blood pressure or heart rate; nor were there any significant statistical interactions with the expectation manipulation. Overall, support expectations had little influence on cardiovascular and behavioral responses. Implications for the study of received support and health are discussed along with potential mechanisms responsible for such links.

Early atherosclerosis and cardiac autonomic responses to mental stress: a population-based study of the moderating influence of impaired endothelial function

Background

Acute mental stress may contribute to the cardiovascular disease progression via autonomic nervous system controlled negative effects on the endothelium. The joint effects of stress-induced sympathetic or parasympathetic activity and endothelial function on atherosclerosis development have not been investigated. The present study aims to examine the interactive effect of acute mental stress-induced cardiac reactivity/recovery and endothelial function on the prevalence of carotid atherosclerosis.

Methods

Participants were 81 healthy young adults aged 24-39 years. Preclinical atherosclerosis was assessed by carotid intima-media thickness (IMT) and endothelial function was measured as flow-mediated dilatation (FMD) using ultrasound techniques. We also measured heart rate, respiratory sinus arrhythmia (RSA), and pre-ejection period (PEP) in response to the mental arithmetic and speech tasks.

Results

We found a significant interaction of FMD and cardiac RSA recovery for IMT (p = 0.037), and a significant interaction of FMD and PEP recovery for IMT (p = 0.006). Among participants with low FMD, slower PEP recovery was related to higher IMT. Among individuals with high FMD, slow RSA recovery predicted higher IMT. No significant interactions of FMD and cardiac reactivity for IMT were found.

Conclusions

Cardiac recovery plays a role in atherosclerosis development in persons with high and low FMD. The role of sympathetically mediated cardiac activity seems to be more important in those with impaired FMD, and parasympathetically mediated in those with relatively high FMD. The development of endothelial dysfunction may be one possible mechanism linking slow cardiac recovery and atherosclerosis via autonomic nervous system mediated effect.