Modeling neuroendocrine stress reactivity in salivary cortisol: adjusting for peak latency variability

The Impact of Time Since Menarche for Depressive and Anxiety Symptom Severity in Adolescence and Young Adulthood

PURPOSE

The study mapped depressive and anxiety symptom trajectories throughout adolescence and early adulthood, arrayed by time since menarche, a novel indicator of pubertal change and examined the effect of age of menarche and pubertal timing, more frequently used variables, on depressive and anxiety symptom severity trajectories.

METHODS

Secondary analysis of a cross-sequential prospective longitudinal investigation included a community sample of 262 US, adolescent females. Participants were enrolled in age cohorts of 11, 13, 15, and 17 years. Four annual waves of data were collected. Self-report of age at menarche was categorized into pubertal timing categories. A novel measure "time since menarche" (chronological age at each wave minus age at menarche), was measured along with depressive and anxiety symptom severity. Two-piece growth curve modeling with landmark registration examined depressive and anxiety symptom severity trajectories according to time since menarche.

RESULTS

There was no change (p > .05) in depression and anxiety symptom severity before menarche; however, in the years leading away from menarche, depression and anxiety symptom severity decreased (p < .05). Age at menarche was not associated with change in depressive and anxiety symptom severity (p > .05) and there were no moderating effects of pubertal timing.

DISCUSSION

Depressive and anxiety symptoms decrease in the years leading away from menarche, suggesting puberty-related psychopathology may be transitory in some individuals. Time since menarche may be a clinically relevant indicator of psychological functioning in pubescent adolescent females. Future studies should examine this variable in larger samples, including more adolescents in the earlier stages of puberty.

Stress-related eating in pregnancy? An RCT examining links between prenatal stress and food choices

BACKGROUND

Diet quality during pregnancy is important for maternal health and offspring development. However, national dietary recommendations are not always met. A potential barrier for healthy food choices might be the experience of stress. Previous literature in non-pregnant populations suggests a negative effect of acute stress on diet quality. This preregistered study is the first to test whether an acute stressor leads to unhealthy food choices in pregnancy and examine the moderating role of stress, depressive and anxiety complaints in daily life.

METHOD

Pregnant women (N = 110, 3rd trimester) completed online self-reported surveys measuring stress, depressive and anxiety complaints in daily life. Hereafter, participants were invited for a laboratory visit, in which they were exposed to the Trier Social Stress Test or a control task. After this manipulation, self-reported and actual food choices and food intake were assessed. At the end of the visit, a hair sample was collected. Throughout the visit, visual analogue scales on negative affect were completed and saliva samples were collected.

RESULTS

The stress group experienced significantly more psychological stress than the control group during the experimental manipulation. Main regression analyses showed that the acute laboratory stressor did not cause unhealthy food choices in the third trimester of pregnancy. In fact, the stress group chose fewer unhealthy foods and consumed fewer kilocalories compared to the control group. Additionally, the findings point at a moderating role of depressive and stress complaints in daily life on food choices within the control group: higher scores were related to more unhealthy food choices and more kilocalories consumed.

DISCUSSION

As this was the first study to test the effect of an acute stressor on food choices in pregnant women, more research is needed to obtain a better understanding of stress-related eating in pregnancy. This knowledge may inform future interventions to support pregnant women in improving their diet quality.

Maltreatment type differences in cortisol stress response trajectories across adolescence

This study examined cortisol stress response trajectories across adolescence in 454 maltreated and comparison youth recruited from Los Angeles County between 2002 and 2005 (66.7% maltreated; 46.7% girls; 39.0% Latino; 37.7% Black; 12.3% Mixed or Biracial; 11.0% White; Mage = 10.9 years, SD = 1.2). Adolescents' peak activation and cortisol reactivity and recovery slopes following the Trier Social Stress Test for Children were calculated at four waves, then used to model peak activation and cortisol reactivity and recovery trajectories arrayed by age. Maltreated youth had blunted cortisol reactivity at age 9 relative to comparison youth (b = -.19, p = .02). Sexually and physically abused youth showed blunted cortisol reactivity and recovery trajectories relative to emotionally abused and neglected youth.

Examining Reactivity and Recovery Patterns of Pain-Evoked Cortisol and Alpha-Amylase Trajectories: Relations Between Psychological Markers of Risk and Resilience

Chronic low back pain (cLBP) is one of the leading causes of disability globally and represents an enormous burden to aging adults. While numerous factors contribute to cLBP, dysregulation in the hypothalamic-pituitary-adrenal axis and autonomic nervous system functioning have been implicated in its pathogenesis. It is well documented that negative psychological states can modulate biological stress responsivity in chronic pain; however, little is known regarding the influence of positive psychological factors in this relationship. The aim of this study was to examine the association between psychological risk and resilience factors with patterns of physiological stress reactivity and recovery in 60 older adults with cLBP. Participants completed measures of hope, optimism, pain catastrophizing, and perceived stress, and underwent psychophysical pain testing assessing responses to painful pressure, heat, and cold stimuli. Salivary samples were obtained prior to pain induction and at 7 time points spanning 90 minutes after pain testing terminated. To examine reactivity and recovery profiles in hypothalamic-pituitary-adrenal axis and autonomic nervous system function, samples were assayed for cortisol and alpha-amylase, respectively. Results revealed higher levels of hope and optimism were associated with increased cortisol reactivity (p's < .003) and more rapid recovery (p's = .001). Further, pain catastrophizing and perceived stress were associated with cortisol reactivity, with lower levels of these factors predicting larger increases in cortisol from baseline to peak levels (p's < .04). No significant differences in reactivity or recovery patterns emerged for alpha-amylase. Overall, findings highlight the role of psychological risk and resilience factors in modulating physiological stress reactivity. PERSPECTIVE: This article investigated whether psychosocial risk and resilience factors were associated with stress reactivity and recovery in response to laboratory-based pain testing in older adults with chronic low back pain. Results indicate that high resilience factors may be protective by modulating adrenocortical reactivity and recovery profiles.

Associations of diurnal cortisol parameters with cortisol stress reactivity and recovery: A systematic review and meta-analysis

Researchers commonly assess the functioning of the hypothalamic-pituitary-adrenal (HPA) axis by measuring natural fluctuations of its end product cortisol throughout the day or in response to a standardized stressor. Although it is conceivable that an individual releasing relatively more cortisol when confronted with a laboratory stressor does the same in everyday life, inconsistencies remain in the literature regarding associations between diurnal cortisol parameters and cortisol stress responses. Hence, the current meta-analysis aggregated findings of 12 studies to examine overall associations of diurnal cortisol parameters (including total output, diurnal slope, and cortisol awakening response [CAR]) with cortisol stress reactivity and recovery in the Trier Social Stress Test (TSST). There were no significant overall associations of total output, slope, or CAR with stress reactivity. Lower total diurnal cortisol output was significantly related to better stress recovery, whereas diurnal slope and CAR were unrelated to stress recovery. Moderation analyses revealed that associations between diurnal cortisol and cortisol stress responses were dependent on the computation method of cortisol parameters, questioning the convergence and validity of commonly employed measures of stress reactivity and recovery. Overall, it seems that we cannot predict characteristics of the diurnal cortisol rhythm from a one-time measure of stress reactivity in a standardized psychosocial laboratory paradigm.

Do diurnal salivary cortisol curves carry meaningful information about the regulatory biology of the HPA axis in healthy humans?

Salivary cortisol stress biomarkers have been extensively used in epidemiological work to document links between stress and ill health. There has been little effort to ground field friendly cortisol measures in the hypothalamic-pituitary-adrenal (HPA) axis regulatory biology that is likely relevant to delineating mechanistic pathways leading from stress exposure to detrimental health outcomes. Here, we utilized a healthy convenience sample (n = 140) to examine normal linkages between extensively collected salivary cortisol measures and available laboratory probes of HPA axis regulatory biology. Participants provided 9 saliva samples per day over 6 days within a month, while engaging in usual activities, and also participated in 5 regulatory tests (adrenocorticoptripin stimulation, dexamethasone/corticotropin-releasing-hormone stimulation, metyrapone, dexamethasone suppression, and Trier Social Stress Test). Logistical regression was used to test specific predictions linking cortisol curve components to regulatory variables and to explore widely for non-predicted associations. We found support for 2 of 3 original hypotheses, showing associations (1) between cortisol diurnal decline and feedback sensitivity as measured by dexamethasone suppression, and (2) between morning cortisol levels and adrenal sensitivity. We did not find links between central drive (metyrapone test) and end of day salivary levels. We confirmed an a priori expectation of limited linkage between regulatory biology and diurnal salivary cortisol measures, beyond those predicted. These data support an emerging focus on measures related to diurnal decline in epidemiological stress work. They raise questions about the biological meaning of other curve components, including morning cortisol levels, and perhaps CAR (Cortisol Awakening Response). If morning cortisol dynamics are linked to stress, more work on adrenal sensitivity in stress adaptation and stress-health links may be warranted.

Effects of stress beliefs on the emotional and biological response to acute psychosocial stress in healthy men

BACKGROUND

Negative beliefs about stress (e.g., "stress is bad") constitute an independent risk factor for increased morbidity and mortality. One potential underlying mechanism are altered responses to acute psychosocial stress. The aim of this study was to investigate whether beliefs about stress are associated with physiological and endocrine stress response patterns.

METHODS

A total of N = 77 healthy adults were randomised to an experimental and a placebo control group and were subsequently exposed to the Trier Social Stress Test (TSST). Stress beliefs were measured before and after a psychological manipulation aiming at fostering more balanced stress beliefs or a placebo manipulation. Self-reported stress was measured four times before/after the TSST, heart rate was assessed continuously, and cortisol was assessed eight times before/after the TSST.

RESULTS

There was a significant decrease in negative stress beliefs (p < .001) and increase in positive stress beliefs (p < .001) in participants in the experimental condition, which was absent in participants in the placebo condition. The participants in the experimental group had more pronounced self-reported stress reactions (p = .028) while at the same time also showing more pronounced stress recoveries (p = .036). The findings regarding cortisol were mixed.

CONCLUSIONS

More balanced stress beliefs appeared to be associated with more efficient subjective responses to acute psychosocial stress. These findings attest to a potential mechanism translating negative stress beliefs into ill health while at the same time outlining targets for psychological interventions.

Prenatal substance exposure, early-life adversity, and parenting: Associations with adolescent stress response

We tested a conceptual model examining associations between prenatal substance exposure and adolescent cortisol reactivity profiles in response to an acute social evaluative stressor. We included cortisol reactivity in infancy, and direct and interactive effects of early-life adversity and parenting behaviors (sensitivity, harshness) from infancy to early school age on adolescent cortisol reactivity profiles in model testing. Participants were 216 families (51% female children; 116 cocaine-exposed) recruited at birth, oversampled for prenatal substance exposure, and assessed from infancy to early adolescence (EA). Majority of participants self-identified as Black (72% mothers, 57.2% adolescents), and caregivers were primarily from low-income families (76%), were single (86%), and had high school or below education (70%) at recruitment. Latent profile analyses identified three cortisol reactivity patterns including elevated (20.4%), moderate (63.1%), and blunted (16.5%) reactivity groups. Prenatal tobacco exposure was associated with higher likelihood of membership in the elevated reactivity compared to the moderate reactivity group. Higher caregiver sensitivity in early life was associated with lower likelihood of membership in the elevated reactivity group. Prenatal cocaine exposure was associated with higher maternal harshness. Interaction effects among early-life adversity and parenting indicated that caregiver sensitivity buffered, and harshness exacerbated, the likelihood that high early adversity would be associated with the elevated and blunted reactivity groups. Results highlight the potential importance of prenatal alcohol and tobacco exposure for cortisol reactivity and the role of parenting as exacerbating or buffering the impact of early-life adversity on adolescent stress response.

Revisiting the stress recovery hypothesis: Differential associations of cortisol stress reactivity and recovery after acute psychosocial stress with markers of long-term stress and health

Exposure to excessive and long-term stress may result in dysregulation of the stress system, including the acute stress response. In particular, failure to downregulate stress-related reactivity may lead to prolonged stress responses and the accumulation of allostatic load. However, the contribution of altered acute cortisol recovery to chronic stress and associated health impairments has often been neglected. Addressing this lack of research, we explored whether recovery from - more so than reactivity to - acute stress captures the basal stress load of an individual. Using Piecewise Growth Curve Models with Landmark Registration, we analyzed cortisol reactivity and recovery slopes of 130 healthy participants exposed to a standardized psychosocial laboratory stressor. Reactivity and recovery were predicted by measures indicative of long-term stress and its downstream effects, including self-report questionnaires, diurnal cortisol indices [cortisol awakening response (CAR); diurnal cortisol slope], markers of pro-inflammatory activity (interleukin-6; high-sensitive C-reactive protein), and hippocampal volume (HCV). Among these measures, only an increased CAR was specifically and consistently associated with relatively impaired recovery. Since the CAR represents the physiological enhancement needed to meet the anticipated demands of the forthcoming day, this finding may highlight the contribution of cognitive processes in determining both CAR and acute stress recovery. Furthermore, greater cortisol reactivity covaried with smaller HCV, showing that increased acute reactivity translates to health-relevant downstream effects. The lack of further associations between long-term and acute stress measures may arise from biases in self-reported chronic stress and the rigorously health-screened study sample. Overall, our findings suggest that while cortisol stress recovery might not supersede reactivity as an indicator of the long-term stress load or associated health effects, recovery and reactivity have differential utility in describing individuals' allostatic states.

Psychological and Physical Abuse and Cortisol Response to Stress: The Moderating Role of Psychosocial Resources

Child abuse is associated with alterations in the hypothalamic-pituitary-adrenal (HPA) axis functioning. However, the unique effects of psychological and physical abuse and protective factors against these effects remain largely unknown. To close these gaps, the present study examined the unique effects of psychological and physical abuse on cortisol stress response and explored the moderating role of psychosocial resources in these associations among a sample of Chinese preadolescent children (N = 150; aged 9-13 years; M_age = 10.69 years; 51% boys). The results showed that both psychological and physical abuse were associated with blunted cortisol reactivity slopes. Psychological abuse, but not physical abuse, was associated with lower peak cortisol values and flatter cortisol recovery slopes. Further, psychosocial resources moderated the association between abuse and hyporesponsiveness of the HPA axis. The association between psychological abuse and lower peak cortisol values and the association between physical abuse and steeper cortisol recovery slopes (faster cortisol recovery following the stressor) were observed only among children with low levels of psychosocial resources. These findings indicate the differential effects of psychological and physical abuse on various phases of cortisol stress response, and the protective role of psychosocial resources. This study also has practical implications, given that preadolescence serves as a critical period for maximizing benefit of interventions of adversity.

Amygdala reactivity during socioemotional processing and cortisol reactivity to a psychosocial stressor

Threat-related amygdala reactivity and the activation of the Hypothalamic-Pituitary-Adrenal (HPA) axis have been linked to negative psychiatric outcomes. The amygdala and HPA axis have bidirectional connections, suggesting that functional variation in one system may influence the other. However, research on the functional associations between these systems has demonstrated mixed findings, potentially due to small sample sizes and cortisol sampling and data analytic procedures that investigate only pre-post differences in cortisol rather than the specific phases of the cortisol stress response. Further, previous research has primarily utilized samples of adults of mostly European descent, limiting generalizability to those of other ethnoracial identities and ages. Therefore, studies addressing these limitations are needed in order to investigate the functional relations between amygdala reactivity to threat and HPA axis stress responsivity. Using a sample of 159 adolescents from a diverse cohort (75% African American, ages 15-17 years), the present study evaluated associations between amygdala reactivity during socioemotional processing using fMRI and HPA axis reactivity to a socially-evaluative cold pressor task. Greater amygdala activation to fearful and neutral faces was associated with greater cortisol peak values and steeper activation slope. As cortisol peak values and cortisol activation slope capture the intensity of the cortisol stress response, these data suggest that greater activation of the amygdala in response to social distress and ambiguity among adolescents may be related to hyper-reactivity of the HPA axis.

Coordination of autonomic and endocrine stress responses to the Trier Social Stress Test in adolescence

Dysregulations in autonomic and endocrine stress responses are linked to the emergence of psychopathology in adolescence. However, most studies fail to consider the interplay between these systems giving rise to conflicting findings and a gap in understanding adolescent stress response regulation. A multisystem framework-investigation of parasympathetic (PNS), sympathetic (SNS), and hypothalamic pituitary adrenal (HPA) axis components and their coordination-is necessary to understand individual differences in stress response coordination which contribute to stress vulnerabilities. As the first investigation to comprehensively evaluate these three systems in adolescence, the current study employed the Trier Social Stress Test in 72 typically developing adolescents (mean age = 13) to address how PNS, SNS, and HPA stress responses are coordinated in adolescence. Hypotheses tested key predictions of the Adaptive Calibration Model (ACM) of stress response coordination. PNS and SNS responses were assessed via heart rate variability (HRV) and salivary alpha amylase (sAA) respectively. HPA responses were indexed by salivary cortisol. Analyses utilized piecewise growth curve modeling to investigate these aims. Supporting the ACM theory, there was significant hierarchical coordination between the systems such that those with low HRV had higher sAA and cortisol reactivity and those with high HRV had low-to-moderate sAA and cortisol responsivity. Our novel results reveal the necessity of studying multisystem dynamics in an integrative fashion to uncover the true mechanisms of stress response and regulation during development. Additionally, our findings support the existence of characteristic stress response profiles as predicted by the ACM model.

Effects of psychosocial stress and performance feedback on pain processing and its correlation with subjective and neuroendocrine parameters

OBJECTIVES

Previous research on stress-induced pain modulation suggests that moderate psychological stress usually leads to hyperalgesia while more severe threat results in hypoalgesia. However, existing studies often lack suitable control conditions imperative to identify mere stress effects. Similarly, research mainly focused on pure anticipation of a social threat, not taking into consideration actual experiences of social evaluation. Therefore, we set out to investigate actual social up- and downgrading combined with a standardized stress paradigm to evaluate short-term and prolonged changes in pain perception and their potential association with neuroendocrine and subjective stress parameters.

METHODS

We allocated 177 healthy women to four experimental conditions, either the standard version of the Trier Social Stress Test (TSST) followed by positive, negative or no performance feedback, or a well-matched but less demanding placebo version of the TSST. Stress responses were assessed with ratings, salivary alpha-amylase, and salivary cortisol. To capture putative effects of stress on pain, heat pain threshold, ratings of phasic heat pain stimuli, and conditioned pain modulation were measured.

RESULTS

Despite a largely successful stress induction, results do not support a reliable influence of experimentally induced social stress-with or without subsequent performance feedback-on pain in women. Further, we found no clear association of pain modulation and changes in neuroendocrine or subjective stress responses.

CONCLUSIONS

Our results contrast previous studies, which repeatedly demonstrated stress-induced hypo- or hyperalgesia. This might be due to methodological reasons as former research was often characterized by high heterogeneity regarding the applied stressors, low sample sizes, and lacking or inconclusive control conditions. Thus, our results raise the question whether pain modulation in women by experimental psychosocial stress might have been overestimated in the past. Future research is necessary, which should employ parametric stress induction methods including well-matched control tasks, taking into consideration the participants' gender/sex and the time course of the stress response relative to pain assessment. The study is registered as DRKS00026946 at 'Deutsches Register Klinischer Studien' (DRKS) and can be also found at the World Health Organization's search portal.

Individual differences in frontal alpha asymmetry moderate the relationship between acute stress responsivity and state and trait anxiety in adolescents

Stress is a risk factor in the development and maintenance of psychopathology, particularly anxiety. Despite theory suggesting differences in stress responsivity may explain heterogeneity in anxiety, findings remain contradictory. This may be due to failure to account for individuals' neurobiological states and outdated methodologic analyses which confound conceptually and biologically distinct stress response pathways. In 145 adolescents, this study examined whether individual differences in neural activation underlying motivational states, indexed by resting frontal alpha asymmetry (FAA) before and after the Trier Social Stress Test (TSST), moderate the relationship between stress responsivity (measured by cortisol) and anxiety. Adolescents with rightward FAA activation (indexed by changes in resting FAA pre-to-post TSST) and high trait anxiety showed blunted cortisol reactivities while those with leftward FAA activation and high state anxiety showed prolonged cortisol recoveries. Our work reveals individual differences in vulnerability to psychosocial stressors and is the first study to show that FAA activation moderates the relationships between anxiety and distinct phases of the stress response in adolescents.

The effect of distraction versus post-event processing on cortisol recovery in individuals with elevated social anxiety

There are preliminary findings that repetitive thinking on social situations (post-event processing; PEP) is associated with impaired cortisol recovery after experiencing social evaluative stressors. However, no studies have examined the effect of experimental manipulation of PEP on cortisol recovery among socially anxious individuals. The aim of the present study was to examine the effect of distraction on cortisol recovery following a social-evaluative stressor in individuals with subclinical social anxiety symptoms. A total of 40 participants, who scored >30 on the Liebowitz Social Anxiety Scale, completed a standardized stress test (the Trier Social Stress Test; TSST). They were then randomized to complete either a 10-min distraction or PEP induction task. Subjective anxiety and salivary cortisol levels were assessed at −20, −10, 0, +10, +20, +30, +40, and +50 min, with respect to the TSST offset. Contrary to the hypothesis, no difference in cortisol recovery was observed between distraction induction and PEP induction. These findings suggest that short-term distraction induction may not be sufficient to promote cortisol recovery in individuals with elevated social anxiety.

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Effect of distraction on cortisol recovery was tested in individuals with elevated social anxiety.

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No effect of distraction on cortisol recovery in comparison to post-event processing induction.

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Short-term distraction induction may not be sufficient for individuals with social anxiety to promote cortisol recovery.

Longitudinal tracking of human plasma oxytocin suggests complex responses to moral elevation

Positive social experiences may induce oxytocin release. However, previous studies of moral elevation have generally utilized cross-sectional and simple modeling approaches to establish the relationship between oxytocin and emotional stimuli. Utilizing a cohort of 30 non-lactating women (aged 23.6 ± 5.7 years), we tested whether exposure to a video identified as capable of eliciting moral elevation could change plasma oxytocin levels. Uniquely, we utilized a high-frequency longitudinal sampling approach and multilevel growth curve modeling with landmark registration to test physiological responses. The moral elevation stimulus, versus a control video, elicited significantly greater reports of being “touched/inspired” and “happy/joyful”. However, the measured plasma oxytocin response was found to be markedly heterogeneous. While the moral elevation stimulus elicited increased plasma oxytocin as expected, this increase was only modestly larger than that seen following the control video. This increase was also only present in some individuals. We found no relationship between plasma oxytocin and self-report responses to the stimulus. From these data, we argue that future studies of the relationship between oxytocin and emotion need to anticipate heterogeneous responses and thus incorporate comprehensive individual psychological data; these should include evidence-based variables known to be associated with oxytocin such as a history of trauma, and the individual’s psychological and emotional state at the time of testing. Given the complexity of physiological oxytocin release, such studies also need to incorporate frequent biological sampling to properly examine the dynamics of hormonal release and response.

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A moral elevation stimulus elicits positive emotional responses

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The human oxytocin responses to a morel elevation stimulus are more heterogenous than previously reported

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Future studies need to utilize longitudinal hormone measurements and comprehensive psychological assessments

DHEA Moderates the Impact of Childhood Trauma on the HPA Axis in Adolescence

BACKGROUND

Trauma can lead to long-term downregulation of the hypothalamic pituitary adrenal (HPA) axis. However, dehydroepiandrosterone (DHEA) has neuroprotective effects that may reduce the need for downregulation of the axis in response to stress. Furthermore, high DHEA/cortisol ratios are often conceptualized as better markers of DHEA's availability than DHEA alone, as ratios account for the coupling of DHEA and cortisol in response to stress.

OBJECTIVES

In this study, we explored if DHEA and DHEA/cortisol ratios moderated the association between childhood maltreatment and the HPA axis stress response.

METHODS

The sample consisted of 101 adolescents (ages 12-16) who completed the Child Trauma Questionnaire (CTQ) and the Trier Social Stress Test (TSST). Cortisol was modeled using saliva samples at 8 time points throughout the TSST. Cortisol and DHEA ratios were examined at baseline and 35 min after stress initiation.

RESULTS

Childhood maltreatment was associated with less steep cortisol activation slope and peak cortisol levels, but DHEA and DHEA/cortisol ratios moderated this effect. At high levels of DHEA, the impact of childhood maltreatment on cortisol peak levels was no longer significant. In contrast, high DHEA/cortisol ratios were associated with an intensification of the impact of childhood maltreatment on peak levels.

CONCLUSIONS

Results suggest that DHEA can limit the blunting of the HPA axis in response to childhood maltreatment. However, this protective effect was not reflected in high DHEA/cortisol ratios as predicted. Therefore, high DHEA and high DHEA/cortisol ratios may reflect different, and potentially opposite, processes.

Feasibility of Combining Transcranial Direct Current Stimulation and Active Fully Embodied Virtual Reality for Visual Height Intolerance: A Double-Blind Randomized Controlled Study

BACKGROUND

Transcranial Direct Current Stimulation (tDCS) and Virtual Reality Exposure Therapy (VRET) are individually increasingly used in psychiatric research.

OBJECTIVE/HYPOTHESIS

Our study aimed to investigate the feasibility of combining tDCS and wireless 360° full immersive active and embodied VRET to reduce height-induced anxiety.

METHODS

We carried out a pilot randomized, double-blind, controlled study associating VRET (two 20 min sessions with a 48 h interval, during which, participants had to cross a plank at rising heights in a building in construction) with online tDCS (targeting the ventromedial prefrontal cortex) in 28 participants. The primary outcomes were the sense of presence level and the tolerability. The secondary outcomes were the anxiety level (Subjective Unit of Discomfort) and the salivary cortisol concentration.

RESULTS

We confirmed the feasibility of the association between tDCS and fully embodied VRET associated with a good sense of presence without noticeable adverse effects. In both groups, a significant reduction in the fear of height was observed after two sessions, with only a small effect size of add-on tDCS (0.1) according to the SUD. The variations of cortisol concentration differed in the tDCS and sham groups.

CONCLUSION

Our study confirmed the feasibility of the association between wireless online tDCS and active, fully embodied VRET. The optimal tDCS paradigm remains to be determined in this context to increase effect size and then adequately power future clinical studies assessing synergies between both techniques.

The effects of a music intervention during port catheter placement on anxiety and stress

Studies have shown that perioperative music interventions can reduce patients' anxiety levels. However, in small operations like port catheter surgery evidence is sparse. The present single-blinded, randomised controlled two-armed study included 84 female patients undergoing port catheter placement who were randomly assigned to either listening to music during surgery vs. no music intervention. The medical staff was blind to group allocation. On the day of the surgery anxiety and stress levels were evaluated using subjective (STAI questionnaire, visual analogue scales) and objective (vital parameters, salivary cortisol) parameters at different time points (before the surgery, at the end of the surgery and 1 h post-surgery). The music group showed significant reductions of systolic blood pressure (from 136.5 mmHg ± 26.1 to 123.3 mmHg ± 22.0, p = .002) and heart rate (from 75.6 bpm ± 12.3 to 73.1 bpm ± 12.2, p = .035) from beginning of the surgery to skin suture, whereas the control group did not. No significant effects of the music intervention on subjective anxiety measures or salivary cortisol were revealed. In sum, the study demonstrates that a music intervention during port catheter placement positively influences physiological anxiety levels, whereas no effects were revealed for subjective anxiety and salivary cortisol. Thus, music can be considered as a low cost addition in clinical routine in order to reduce patients' heart rate and blood pressure. Future studies are encouraged to further explore the differential effects of intraoperative music interventions on physiological, endocrinological and subjective anxiety levels.

Perceived Social Support and Children's Physiological Responses to Stress: An Examination of the Stress-Buffering Hypothesis

OBJECTIVE

The current study aimed to examine the stress-buffering effect of children's perceived social support on their hypothalamic-pituitary-adrenocortical axis and autonomic nervous system reactivity to an acute laboratory stressor.

METHODS

A sample of 150 children (aged 9-13 years, mean [standard deviation] age = 10.69 [0.93] years, 74 girls) reported perceived social support, stressful life events, and underwent the Modified Trier Social Stress Test, during which six saliva samples were collected. A two-piece multilevel growth curve model with landmark registration was used to detect trajectory differences in the reactivity and recovery phases of the stress response and account for individual variation in the timing of poststressor peak hormone concentrations.

RESULTS

The interaction between stressful life events and perceived social support significantly predicted poststressor peak cortisol levels (β = 0.0805, SE = 0.0328, p = .015) and cortisol recovery slope (β = -0.0011, SE = 0.0005, p = .040). Children with more life events and low social support exhibited the lowest poststressor peak cortisol levels and the flattest cortisol recovery slope. In contrast, children high in stressful life events and high in social support displayed cortisol response profiles more similar to those of children with low stressful life events. Conversely, there were no statistically significant two-way interactions of stressful life events and perceived social support on salivary α-amylase parameters (i.e., poststressor peak [p = .38], reactivity slope [p = .81], and recovery slope [p = .32]).

CONCLUSIONS

These results provide preliminary evidence for the buffering effect of children's perceived social support on the association between life stress and hypothalamic-pituitary-adrenocortical axis response profiles.

The effect of sleep on the salivary cortisol response to acute stressors: a review and suggestions

There have been steadily increasing studies on the relationship between sleep and stress. However, the findings regarding the effects of sleep on the acute stress response have been inconsistent. Elevated, blunted, or unchanged salivary cortisol stress response have been reported. Therefore, this study conducted a systematic review of previous studies to provide a comprehensive summary of the factors that influence the effects of sleep on the salivary cortisol stress response. We conducted a comprehensive electronic literature search in PubMed, PsycINFO, PsycARTICLES, Web of Science, MEDLINE, and EMBASE for human studies published in English (up to June 2019). Finally, 17 articles with participants aged 6.4-72 years were included in this review. We assessed the following factors: designing factors (sleep measurement, stress induction, cortisol sampling period, and time intervals between sleep measurement and the acute stress task), analyzing factors (cortisol analysis), and participants' characteristics (age, sex, and background stress levels); subsequently, we explained conflicting findings across the current literature. Further, we provide study design, analysis, and report suggestions for optimal assessment of the effects of sleep on the acute stress response. This summary of influencing factors and suggestions for future studies could help elucidate the impact of sleep on stress and advance the field.

Bedtime Stress Increases Sleep Latency and Impairs Next-Day Prospective Memory Performance

The cognitive construct of prospective memory (PM) refers to the capacity to encode, retain and execute delayed intentions (e.g. to remember to buy milk on the way home). Although previous research suggests that PM performance is enhanced by healthy sleep, conclusions tend to be drawn based on designs featuring ecologically unnatural manipulations (e.g. total sleep deprivation). This study investigates whether a more common everyday experience (bedtime stress) affects next-day PM performance and, in so doing, also contributes to the heretofore inconsistent literature on stress and PM. Forty young adults received PM task instructions and were then assigned to either a stress condition (exposure to a laboratory-based stress-induction manipulation; n = 20, 9 women) or a non-stress condition (exposure to a non-stressful control manipulation; n = 20, 12 women). After completing the experimental manipulation, all participants had their objective sleep quality measured over a full night of polysomnographic monitoring. Upon awakening, they completed the PM task. Analyses detected significant between-group differences in terms of stress outcomes, sleep quality and PM performance: Participants exposed to the manipulation experienced heightened signs of stress (captured using a composite variable that included self-report, psychophysiological and endocrinological measures), had longer sleep latencies and poorer sleep depth and displayed significantly longer reaction times to PM cues. An interaction between experimental condition (being exposed to the stressor) and disrupted sleep (longer sleep latency) significantly predicted poorer next-day PM reaction time. We interpret these findings as indicating that bedtime stress, which leads to heightened presleep arousal, affects sleep processes and, consequently, the deployment of attentional resources during next-day execution of a delayed intention.

The effect of HF-rTMS over the left DLPFC on stress regulation as measured by cortisol and heart rate variability

The prefrontal cortex, and especially the Dorsolateral Prefrontal Cortex (DLPFC), plays an inhibitory role in the regulation of the Hypothalamic-Pituitary-Adrenal (HPA) axis under stressful situations. Moreover, recent evidence suggests that a sustained DLPFC activation is associated with adaptive stress regulation in anticipation of a stressful event, leading to a reduced stress-induced amygdala response, and facilitating the confrontation with the stressor. However, studies using experimental manipulation of the activity of the DLPFC before a stressor are scarce, and more research is needed to understand the specific role of this brain area in the stress-induced physiological response. This pre-registered study investigated the effect on stress regulation of a single excitatory high frequency (versus sham) repetitive transcranial magnetic stimulation (HF-rTMS) session over the left DLPFC applied before the Trier Social Stress Test in 75 healthy young women (M = 21.05, SD = 2.60). Heart rate variability (HRV) and salivary cortisol were assessed throughout the experimental protocol. The active HF-rTMS and the sham group showed a similar cognitive appraisal of the stress task. No differences in HRV were observed during both the anticipation and the actual confrontation with the stress task and therefore, our results did not reflect DLPFC-related adaptive anticipatory adjustments. Importantly, participants in the active HF-rTMS group showed a lower cortisol response to stress. The effect of left prefrontal HF-rTMS on the stress system provides further critical experimental evidence for the inhibitory role played by the DLPFC in the regulation of the HPA axis.

Violence exposure and social deprivation is associated with cortisol reactivity in urban adolescents

The present study tested how two different dimensions of childhood adversity, violence exposure and social deprivation, were associated with the cortisol response to the Socially Evaluated Cold-Pressor task in a sample of 222 adolescents (n = 117 girls, n = 167 African American). Participants were part of the Fragile Families and Child Wellbeing Study, a probability sample of births in large US cities (>200,000) between 1998 and 2000. Our subsample includes births in three cities: Detroit, Toledo, and Chicago. The study design called for an oversampling of births to unmarried parents (3:1) which led to a large number of minority and economically disadvantaged adolescents. When children were ages 3, 5, and 9, mothers reported on exposures to violence and social deprivation that occurred in the past year. Exposures from the three waves were averaged to reflect violence exposure and social deprivation during childhood. Greater levels of violence exposure from ages 3 to 9 were associated with a blunted cortisol response to stress at age 15, even after controlling for social deprivation and other factors known to influence cortisol reactivity. Social deprivation from ages 3 to 9 was not associated with the cortisol response to stress; though in an exploratory analysis, social deprivation moderated the association between violence exposure and cortisol peak activation. In line with the Dimensional Model of Adversity and Psychopathology, these findings suggest that experiences of violence, but not social deprivation, during childhood may contribute to cortisol blunting that has been previously reported in samples with high levels of social deprivation. Findings from the present longitudinal study on a relatively large sample of under-represented minority youth provide insight into the ways two different dimensions of childhood adversity impact the cortisol response to stress.

Subjective social status and stress responsivity in late adolescence

Subjective social status (SSS) reflects one's perception of one's standing within society. SSS has been linked with health outcomes, over and above socioeconomic status, and is thought to influence health in part by shaping stress responsivity. To test this, the present study examined the links between SSS and psychological, hypothalamic-pituitary-adrenal (HPA) axis, and cardiovascular responsivity in a sample of 87 ethnically diverse late adolescents (Mage = 18.39 years). Participants rated their family's SSS while either in high school (n = 50) or 1 year afterward (n = 37). Participants completed the Trier Social Stress Task (TSST) and reported their fear during baseline and after task completion, provided six saliva samples throughout the task, and had their heart rate monitored continuously throughout the task. Multilevel models, with time points nested within participants, were conducted to assess reactivity and recovery for each outcome. Results indicated that lower SSS was associated with greater fear reactivity and faster rates of HPA axis reactivity and recovery to baseline. Regarding cardiovascular responses, no differences were observed with respect to heart rate. Lower SSS predicted increased respiratory sinus arrhythmia during the stress task only among participants who rated their SSS while in high school; no association was observed for those who rated SSS after high school. Results suggest that perceptions of one's family's standing in society can shape responses to stress and potentially broader health.HighlightsSubjective social status (SSS) was linked with differences in stress responsivity. Specifically, lower SSS was associated with greater increases in fear following an acute stressor and faster rates of cortisol reactivity and recovery. Adolescents with lower SSS in high school showed less cardiovascular reactivity and recovery with respect to respiratory sinus arrhythmia, a marker of parasympathetic nervous system activity.

Socially oriented thinking and the biological stress response: Thinking of friends and family predicts trajectories of salivary cortisol decline

The cortisol stress response has been related to perceived social support, but previous studies rely on self-reported social support variables. The cortisol recovery phase in particular has been theorized to serve a social coping function, but individual differences in recovery slope have not yet been examined in relation to social coping-relevant indices. This study addressed these gaps by examining the relationship of cortisol trajectories after a socioevaluative task to individual differences in covertly assessed cognitions related to close social relationships. We examined trajectories of cortisol change related to socially oriented thinking, the semi-implicit activation of cognitive representations of friends or family. Young adults (N = 64) gave salivary cortisol samples before and for 45 min after a speech task. Participants' thoughts were sampled repeatedly; the frequency of words related to friends or family was assessed to index socially oriented thinking. A free curve slope intercept latent growth curve model showed excellent fit with the cortisol data. Socially oriented thinking was unrelated to overall magnitude of cortisol response to the task (latent intercept) but predicted the latent cortisol trajectory, independently of cortisol intercept and baseline cortisol levels. Socially oriented thinkers showed more gradual cortisol declines, whereas nonsocially oriented thinkers showed a steeper downslope driven primarily by cortisol changes 45 min after the task. Individual differences in socially oriented thinking may manifest in different rates of biological changes following a performance task.

Habitual and acute exercise effects on salivary biomarkers in response to psychosocial stress

OBJECTIVE

Previous research suggests beneficial effects of physical exercise on stress reactivity due to cross-stressor adaptions of physiological stress response systems. However, results remain inconclusive and it is unclear whether only regular engagement in exercise modulates these physiological adaptations or if acute bouts of exercise can elicit similar adaptations. Thus, the aim of the current study was to investigate and compare the effects of habitual and acute exercise on physiological stress responses.

METHODS

84 male participants between 18 and 30 years (half of them were screened to be habitually high active or low active) were randomized into one of two groups: either an acute exercise intervention group (n = 42 with 50% being habitually high active) which engaged in 30 min of moderate-to-high intensity ergometer bicycling, or a control (placebo exercise) group which engaged in 30 min of light stretching (n = 42 with 50% being habitually high active). Following the intervention period, participants took part in a well validated psychosocial stress paradigm. Saliva samples were taken repeatedly to derive alpha-amylase and cortisol as stress-specific parameters. A multilevel growth curve approach was applied to analyse changes in the stress parameters over time.

RESULTS

Both, acute and habitual exercise have shown to be positively related to stress reactivity. In particular, a reduction in stress activation was found for both types of exercise, but only habitual engagement in exercise exhibited a beneficial effect on peak cortisol levels.

CONCLUSIONS

Taken together, people can profit from regular exercise (i.e. reduced activity of stress-response systems). However, even acute bouts of exercise preceding stress exposure showed beneficial effects on stress reactivity. This finding is particularly important as it may provide a (self-)regulatory mechanism for people facing conceivable acute stress situations.

Interactive effects of family instability and adolescent stress reactivity on socioemotional functioning

This study investigated whether adolescent vagal stress reactivity to parent-adolescent conflict moderates the effects of family instability on the development of adolescent behavioral problems. Participants were 192 adolescents (M age = 12.4) and their parents across 2 measurement occasions. Results indicated that the interaction between family instability and vagal stress reactivity significantly predicted change in externalizing problems. Greater family instability was associated with increases in externalizing problems only for adolescents showing greater vagal suppression (i.e., higher vagal reactivity) during a laboratory triadic family conflict discussion. Further tests suggested the interaction was consistent with diathesis stress, such that adolescents with higher vagal stress reactivity show higher increases in externalizing problems under high instability but not lower increases in externalizing symptoms with low family instability. Findings indicate disruptions in the proximal rearing contexts may differentially influence development for adolescents, but the impact may differ as a function of stress reactivity. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Adolescent stress reactivity: Examining physiological, psychological and peer relationship measures with a group stress protocol in a school setting

INTRODUCTION

Adolescents experience enhanced social sensitivity and biopsychosocial changes that can be challenging. Much remains unknown about the effect of psychological characteristics and peer relationships on adolescents' physiological responses to stress, due in part to methodological limitations.

METHODS

To test how adolescents' peer relationships and psychological characteristics are associated with their physiological and psychological response to stress, we administered the Group Public Speaking Task for Adolescents (GPST-A) to 54 adolescents (n = 40 girls; Mage = 16.6 years) in two high schools in the United States. Salivary cortisol and alpha-amylase (sAA), and positive and negative affect were measured six times. Relationships among group members were measured, resulting in whole-network data. State and trait rumination, five factors of coping, and emotional reappraisal and suppression were measured along with symptoms of depression and anxiety.

RESULTS

Greater levels of negative evaluation and victimization among group members were associated with a steeper increase and decline in the negative affect response, yet not associated with the physiological response to stress. Greater positive affect was associated with decreased cortisol reactivity, whereas negative affect was associated with steeper cortisol and sAA reactivity. Rumination, disengagement coping, and depression symptoms were related to the physiological response to stress.

CONCLUSIONS

The GPST-A is feasible to administer in a school context with adolescents to collect both physiological and psychological stress responses. Findings from the present study suggest peer relationships are important for understanding adolescents' psychological response to stressors while psychological characteristics are important for adolescents' physiological response to stress.

Associations between symptoms of depression and anxiety and cortisol responses to and recovery from acute stress

BACKGROUND

Anxiety disorders and major depressive disorder (MDD) have been associated with increased and blunted HPA axis reactivity to social stress. However, research focusing on associations between HPA axis responses to stress and symptoms of anxiety and depression among individuals without a diagnosis remains an understudied area of research.

METHODS

One hundred forty-three adults (52% female) completed the Trier Social Stress Test (TSST). Symptoms of depression and anxiety were assessed prior to the TSST using the anxiety and depression subscales of the Hospital Anxiety and Depression Scale (HADS). HPA axis responses were assessed by measuring salivary cortisol at baseline and following the TSST. Reactivity to and recovery from stress were assessed using multilevel growth modeling controlling for age, BMI, and sex among the full sample and a subset of cortisol responders (n = 72).

RESULTS

Anxiety symptoms were positively associated with flatter recovery slopes among the full sample (t(122.3) = 2.082, p = .039). Among cortisol responders, depression symptoms were associated with steeper reactivity (t(63.32) = 2.53, p = .026) and recovery (t(58.75)=-2.20, p = .03). Anxiety symptoms were associated with marginally flatter reactivity (t(64.00)=-1.97, p = .053) and significantly flatter recovery (t(59.22) = 2.29, p = .025).

CONCLUSION

Symptoms of anxiety and depression among individuals without a psychiatric diagnosis are associated with blunted and exaggerated cortisol responses to and recovery from stress. Such patterns could indicate increased risk for unhealthy HPA axis dysregulation, allostatic load, and disease.

Effects of post-exposure naps on exposure therapy for social anxiety

Exposure therapy for social anxiety disorder (SAD) utilizes fear extinction, a memory process enhanced by sleep. We investigated whether naps following exposure sessions might improve symptoms and biomarkers in response to social stress in adults undergoing 5-week exposure-based group SAD therapy. Thirty-two participants aged 18-39 (18 females) with SAD were randomized. Before and after treatment, participants completed the Liebowitz Social Anxiety Scale (LSAS) and underwent a Trier Social Stress Test with psychophysiological monitoring (mpTSST) that included skin conductance (SCL), electromyographic (EMG) and electrocardiographic recording, and an auditory startle procedure while anticipating the social stressor. At sessions 3 and 4, exposure was followed by either a 120-min polysomnographically monitored sleep opportunity (Nap, N = 17) or wakefulness (Wake, N = 15). Primary hypotheses about SAD symptom change (LSAS) and EMG blink-startle response failed to differ with naps, despite significant symptom improvement (LSAS) with therapy. Some secondary biomarkers, however, provided preliminary support for enhanced extinction learning with naps, with trend-level Time (pre-, post-treatment) × Arm interactions and significant reduction from pre- to post treatment in the Nap arm alone for mpTSST SCL and salivary cortisol rise. Because of the small sample size and limited sleep duration, additional well-powered studies with more robust sleep interventions are indicated.

Altered ultradian cortisol rhythmicity as a potential neurobiologic substrate for chronic insomnia

Chronic insomnia is highly prevalent and associated with significant morbidity (i.e., confers risk for multiple psychiatric and medical disorders, such as depression and hypertension). Therefore, it is essential to identify factors that perpetuate this disorder. One candidate factor in the neurobiology of chronic insomnia is hypothalamic-pituitary-adrenal-axis dysregulation, and in particular, alterations in circadian cortisol rhythmicity. Cortisol secretory patterns, however, fluctuate with both a circadian and an ultradian rhythm (i.e., pulses every 60-120 min). Ultradian cortisol pulses are thought to be involved in the maintenance of wakefulness during the day and their relative absence at night may allow for the consolidation of sleep and/or shorter nocturnal awakenings. It is possible that the wakefulness that occurs in chronic insomnia may be associated with the aberrant occurrence of cortisol pulses at night. While cortisol pulses naturally occur with transient awakenings, it may also be the case that cortisol pulsatility becomes a conditioned phenomenon that predisposes one to awaken and/or experience prolonged nocturnal awakenings. The current review summarizes the literature on cortisol rhythmicity in subjects with chronic insomnia, and proffers the suggestion that it may be abnormalities in the ultradian rather than circadian cortisol that is associated with the pathophysiology of insomnia.

Elevated Cortisol Leaves Working Memory Unaffected in Both Men and Women

Activation of the hypothalamic-pituitary-adrenal (HPA) axis (as might occur, for example, when the organism encounters a threat to allostatic balance) leads to the release of cortisol into the bloodstream and, ultimately, to altered neural functioning in particular brain regions (e.g., the prefrontal cortex (PFC)). Although previous studies suggest that exposure to acute psychosocial stress (and hence, presumably, elevation of circulating cortisol levels) enhances male performance on PFC-based working memory (WM) tasks, few studies have adequately investigated female performance on WM tasks under conditions of elevated cortisol. Hence, we compared associations between elevated (relative to baseline) levels of circulating cortisol and n-back performance in a South African sample (38 women in the late luteal phase of their menstrual cycle, 38 men). On Day 1, participants completed practice n-back tasks. On Day 2, some completed the Trier Social Stress Test (TSST), whereas others experienced a relaxation period, before completing 1-back and 3-back tasks. We measured self-reported anxiety and salivary cortisol at baseline, post-manipulation and end of session. We reconstituted group assignment so that all women with elevated cortisol were in one group (EC-Women; n = 17), all men with elevated cortisol were in another (EC-Men; n = 19), all women without elevated cortisol were in a third (NoEC-Women; n = 21), and all men without elevated cortisol were in a fourth (NoEC-Men; n = 19) group. Analyses suggested this reconstitution was effective: in EC, but not NoEC, groups cortisol levels rose significantly from baseline to post-manipulation. Analyses of n-back data detected significant relations to task load (i.e., better performance on 1-back than on 3-back tasks), but no significant relations to sex, performance accuracy/speed, or cortisol variation. The data patterns are inconsistent with reports describing sex differences in effects of stress on WM performance. We speculate that cross-study methodological differences account for these inconsistencies, and, particularly, that between-study variation in the magnitude of baseline cortisol levels might affect outcomes. For instance, diurnal cortisol rhythms of South African samples might have flatter curves, and lower baseline values, than predominantly Caucasian samples from the United States and western Europe due to greater prenatal and lifetime stress, more socioeconomic disadvantage and faster ancestral life history (LH) strategies. We describe ways to disconfirm this hypothesis, and urge further cross-national research exploring these possibilities.

Relationship of Mindfulness to Distress and Cortisol Response in Adolescent Girls At-Risk for Type 2 Diabetes

Altered stress response theoretically contributes to the etiology of cardiometabolic disease. Mindfulness may be a protective buffer against the effects of stress on health outcomes by altering how individuals evaluate and respond to stress. We engaged adolescent girls at risk for developing Type 2 diabetes in a cold-pressor test in order to determine the relationship of dispositional mindfulness to cortisol response and subjective stress, including perceived pain and unpleasantness during the stressor, and negative affect following the stressor. We also evaluated mindfulness as a moderator of psychological distress (depressive/anxiety symptoms) and stress response. Participants were 119 girls age 12-17 years with overweight/obesity, family history of diabetes, and mild-to-moderate depressive symptoms. Greater mindfulness was associated with less perceived pain and negative affect, but was unrelated to cortisol response to the stressor. Regardless of mindfulness, greater depressive/anxiety symptoms related to a more blunted cortisol response. Mindfulness might promote better distress tolerance in adolescents at risk for diabetes by altering how youth perceive and relate to acute stress, rather than through altering the physiological stress response. At all levels of mindfulness, depressive/anxiety symptoms relate to greater blunting of cortisol response. Findings contribute to emerging literature on the role of mindfulness in promoting the mental and physical health and well-being of individuals at risk for Type 2 diabetes.

How to disentangle psychobiological stress reactivity and recovery: A comparison of model-based and non-compartmental analyses of cortisol concentrations

This article seeks to address the prevailing issue of how to measure specific process components of psychobiological stress responses. Particularly the change of cortisol secretion due to stress exposure has been discussed as an endophenotype of many psychosomatic health outcomes. To assess its process components, a large variety of non-compartmental parameters (i.e., composite measures of substance concentrations at different points in time) like the area under the concentration-time curve (AUC) are commonly utilized. However, a systematic evaluation and validation of these parameters based on a physiologically plausible model of cortisol secretion has not been performed so far. Thus, a population pharmacokinetic (mixed-effects stochastic differential equation) model was developed and fitted to densely sampled salivary cortisol data of 10 males from Montreal, Canada, and sparsely sampled data of 200 mixed-sex participants from Dresden, Germany, who completed the Trier Social Stress Test (TSST). Besides the two major process components representing (1) stress-related cortisol secretion (reactivity) and (2) cortisol elimination (recovery), the model incorporates two additional, often disregarded components: (3) the secretory delay after stress onset, and (4) deviations from the projected steady-state concentration due to stress-unrelated fluctuations of cortisol secretion. The fitted model (R² = 99%) was thereafter used to investigate the correlation structure of the four individually varying, and readily interpretable model parameters and eleven popular non-compartmental parameters. Based on these analyses, we recommend to use the minimum-maximum cortisol difference and the minimum concentration as proxy measures of reactivity and recovery, respectively. Finally, statistical power analyses of the reactivity-related sex effect illustrate the consequences of using impure non-compartmental measures of the different process components that underlie the cortisol stress response.

Is cortisol production in response to an acute stressor associated with diurnal cortisol production during adolescence?

The goal of the current study was to examine the extent to which cortisol responding to an acute stressor is related to diurnal cortisol patterns during adolescence. Participants were 105 adolescents (10-17 years of age) who experienced a robust social-evaluative stressor and provided saliva samples (before and immediately after, as well as 10, 20, and 30 min after the stressor) to assess both cortisol reactivity and recovery and also provided saliva samples (at wake-up, 30 min after wake-up, 4 pm, and at bedtime) on two consecutive days to measure diurnal cortisol production. Dual process latent growth curve models, one for cortisol reactivity and one for diurnal cortisol, indicated that dampened cortisol reactivity and prolonged cortisol recovery (i.e., less cortisol produced during reactivity but more cortisol produced during recovery) were associated with dampened decreases in cortisol production across the day, suggesting that adolescents are likely to show attenuation in multiple components of HPA axis functioning.

HPA-Axis Activation as a Key Moderator of Childhood Trauma Exposure and Adolescent Mental Health

Individual differences in a child's sensitivity to stress may influence whether youth exposed to trauma develop symptoms of psychopathology. We examined the interaction between HPA-axis reactivity to an acute stressor and exposure to different types of childhood trauma as predictors of mental health symptoms in a sample of youth. Youth (n = 121, ages 9-16; 47% female) completed a standardized stress task, including 5 post-stress salivary cortisol samples. Parents also completed the Child Behavior Checklist as a measure of child internalizing and externalizing symptoms in the past month, and completed the Early Trauma Inventory (ETI) as a measure of their child's trauma exposure. More emotional abuse and non-intentional trauma were associated with greater internalizing symptoms. Youth exposed to physical abuse who demonstrated slower HPA-axis reactivity had elevated internalizing and externalizing symptoms. Youth exposed to emotional abuse or non-intentional traumatic events who demonstrated faster HPA-axis reactivity had elevated internalizing and externalizing symptoms. Profiles of exaggerated or attenuated HPA-axis reactivity to acute stress may be risk factors for psychopathology in children facing different stressful social environments.

Cortisol and salivary alpha-amylase trajectories following a group social-evaluative stressor with adolescents

Intraindividual variability in stress responsivity and the interrelationship of multiple neuroendocrine systems make a multisystem analytic approach to examining the human stress response challenging. The present study makes use of an efficient social-evaluative stress paradigm - the Group Public Speaking Task for Adolescents (GPST-A) - to examine the hypothalamic-pituitary-adrenocortical (HPA)-axis and Autonomic Nervous System (ANS) reactivity profiles of 54 adolescents with salivary cortisol and salivary alpha-amylase (sAA). First, we account for individuals' time latency of hormone concentrations between individuals. Second, we use a two-piece multilevel growth curve model with landmark registration to examine the reactivity and recovery periods of the stress response separately. This analytic approach increases the models' sensitivity to detecting trajectory differences in the reactivity and recovery phases of the stress response and allows for interindividual variation in the timing of participants' peak response following a social-evaluative stressor. The GPST-A evoked typical cortisol and sAA responses in both males and females. Males' cortisol concentrations were significantly higher than females' during each phase of the response. We found no gender difference in the sAA response. However, the rate of increase in sAA as well as overall sAA secretion across the study were associated with steeper rates of cortisol reactivity and recovery. This study demonstrates a way to model the response trajectories of salivary biomarkers of the HPA-axis and ANS when taking a multisystem approach to neuroendocrine research that enables researchers to make conclusions about the reactivity and recovery phases of the HPA-axis and ANS responses. As the study of the human stress response progresses toward a multisystem analytic approach, it is critical that individual variability in peak latency be taken into consideration and that accurate modeling techniques capture individual variability in the stress response so that accurate conclusions can be made about separate phases of the response.

Post-event Processing Predicts Impaired Cortisol Recovery Following Social Stressor: The Moderating Role of Social Anxiety

There is growing evidence that individuals with social anxiety show impaired cortisol recovery after experiencing social evaluative stressors. Yet, little is known regarding the cognitive processes underlying such impaired cortisol recovery. The present study examined the effect of post-event processing (PEP), referred to as repetitive thinking about social situations, on cortisol recovery following a social stressor. Forty-two non-clinical university students (23 women, 19 men, mean age = 22.0 ± 2.0 years) completed the Trier Social Stress Test (TSST), followed by a thought sampling procedure which assessed the frequency of PEP reflecting the TSST. A growth curve model showed PEP and social anxiety interactively predicted cortisol recovery. In particular, PEP predicted impaired cortisol recovery in those with low levels of social anxiety but not in those with high levels of social anxiety, which contradicted the initial hypothesis. These findings suggest that PEP is differentially associated with cortisol recovery depending on levels of social anxiety. The possible mechanisms underlying these findings were discussed in terms of protective inhibition framework.

The cortisol awakening response after sleep deprivation: Is the cortisol awakening response a "response" to awakening or a circadian process?

This study tested whether the cortisol awakening response is dependent on the transition from sleep to awakening, or alternatively, a circadian-driven process that is independent of awakening. A total of 40 participants were randomly assigned to either a total sleep deprivation or a sleep condition. Salivary cortisol was also assessed. Participants in the sleep condition demonstrated a traditional cortisol awakening response, whereas participants in the total sleep deprivation condition showed no increases in morning cortisol. These results are consistent with the notion that if circadian-driven processes are related to the cortisol awakening response, they may only be activated when awakening occurs or is anticipated.

Physiological attunement in mother–infant dyads at clinical high risk: The influence of maternal depression and positive parenting

A growing number of research studies have examined the intradyadic coregulation (or attunement) of hypothalamus–pituitary–adrenal axis functioning in mothers and their children. However, it is unclear how early this coregulation may be present in dyads at clinical high risk and whether certain factors, such as maternal depression or positive parenting, are associated with the strength of this coregulation. The present study examined cortisol attunement within mother–infant dyads in a high-risk sample of 233 mothers who received treatment for psychiatric illness during pregnancy and whose infants were 6 months old at the study visit. Results showed that maternal and infant cortisol covaried across four time points that included a stressor paradigm and a mother–infant interaction task. Greater maternal positive affect, but not depression, predicted stronger cortisol attunement. In addition, infants’ cortisol level following separation from the mother predicted mothers’ cortisol level at the next time point. Mothers’ cortisol level following the separation and the laboratory stress paradigm predicted infants’ cortisol levels at each successive time point, over and above infants’ own cortisol at the previous time point. These findings suggest that maternal and infant cortisol levels influence one another in a bidirectional fashion that may be temporally and context dependent.

Developmental psychoneuroendocrine and psychoneuroimmune pathways from childhood adversity to disease

Childhood adversity has been repeatedly and robustly linked to physical and mental illness across the lifespan. Yet, the biological pathways through which this occurs remain unclear. Functioning of the inflammatory arm of the immune system and the hypothalamic-pituitary-adrenal (HPA)-axis are both hypothesized pathways through which childhood adversity leads to disease. This review provides a novel developmental framework for examining the role of adversity type and timing in inflammatory and HPA-axis functioning. In particular, we identify elements of childhood adversity that are salient to the developing organism: physical threat, disrupted caregiving, and unpredictable environmental conditions. We propose that existing, well-characterized animal models may be useful in differentiating the effects of these adversity elements and review both the animal and human literature that supports these ideas. To support these hypotheses, we also provide a detailed description of the development and structure of both the HPA-axis and the inflammatory arm of the immune system, as well as recent methodological advances in their measurement. Recommendations for future basic, developmental, translational, and clinical research are discussed.

The Cortisol Awakening Response and Depressive Symptomatology: The Moderating Role of Sleep and Gender

The association between depression and the cortisol awakening response (CAR) has been widely examined, yet the results are mixed and factors responsible for such inconsistencies are poorly understood. The current study investigated whether the link between depressive symptomatology and CAR varied as a function of two such factors: sleep and gender. The sample included 58 young adults (30 females; M_age  = 18.7; SD_age  = 0.91). Participants completed the Beck Depression Inventory as well as the Consensus Sleep Diary to assess depressive symptomatology and daily sleep patterns, respectively. Participants also provided four salivary cortisol samples (0, 30, 45 and 60 min after awakening) during two consecutive weekdays. Results demonstrated that greater depressive symptoms were associated with a greater CAR but only when depressive symptoms were linked to a shorter sleep time. In addition, gender significantly moderated the association between depressive symptoms and CAR. While greater depressive symptoms were associated with an elevated CAR among females, they were associated with a blunted CAR among males. These findings provide some insight into potential mechanisms linking depressive symptomatology and CAR, and suggest that future studies examining CAR as a biomarker of depression should account for differences in sleep and gender. Copyright © 2016 John Wiley & Sons, Ltd.

Investigating the effect of acute sleep deprivation on hypothalamic-pituitary-adrenal-axis response to a psychosocial stressor

The hypothalamic-pituitary-adrenal (HPA) axis has been previously identified as one potential mechanism that may explain the link between sleep deprivation and negative health outcomes. However, few studies have examined the direct association between sleep deprivation and HPA-axis functioning, particularly in the context of stress. Therefore, the aim of the current study was to investigate the relationship between acute sleep deprivation and HPA-axis reactivity to a psychosocial stressor. Participants included 40 healthy, young adults between the ages of 18-29. The current protocol included spending two nights in the laboratory. After an adaptation night (night 1), participants were randomized into either a sleep deprivation condition (29 consecutive hours awake) or a control condition (night 2). Following the second night, all participants completed the Trier Social Stress Test (TSST). Salivary cortisol was collected before, during, and after the TSST. Results indicated that there were significant group differences in cortisol stress reactivity. Specifically, compared to participants in the control condition, participants in the sleep deprivation condition had greater baseline (i.e., pre-stress) cortisol, yet a blunted cortisol response to the TSST. Taken together, a combination of elevated baseline cortisol (and its subsequent effect on HPA-axis regulatory processes) and a relative 'ceiling' on the amount of cortisol a laboratory stressor can produce may explain why participants in the sleep deprivation condition demonstrated blunted cortisol responses.

Cortisol reactivity to stress among youth: stability over time and genetic variants for stress sensitivity

Stress sensitivity may be one process that can explain why some genetically at-risk individuals are more susceptible to some types of stress-reactive psychopathologies. Dysregulation of the limbic-hypothalamic-pituitary-adrenal (LHPA) axis, including cortisol reactivity to challenge, represents a key aspect of stress sensitivity. However, the degree of stability over time among youth, especially differential stability as a function of particular genetic variants, has not been investigated. A general community sample of children and adolescents (mean age = 11.4; 56% girls) provided a DNA sample and completed 2 separate laboratory stress challenges, across an 18-month follow-up (N = 224 at Time 1; N = 194 at Time 2), with repeated measures of salivary cortisol. Results showed that test-retest stability for several indices of cortisol reactivity across the laboratory challenge visits were significant and of moderate magnitude for the whole sample. Moreover, gene variants of several biologically plausible systems relevant for stress sensitivity (especially 5-HTTLPR and CRHR1) demonstrated differential stability of cortisol reactivity over 18-months, such that carriers of genotypes conferring enhanced environmental susceptibility exhibited greater stability of cortisol levels over time for some LHPA axis indices. Findings suggest that LHPA axis dysregulation may exhibit some trait-like aspects underlying stress sensitivity in youth, especially for those who carry genes related to greater genetic susceptibility to environmental stress.

Child anxiety symptoms related to longitudinal cortisol trajectories and acute stress responses: evidence of developmental stress sensitization

Cross-sectional research suggests that individuals at risk for internalizing disorders show differential activation levels and/or dynamics of stress-sensitive physiological systems, possibly reflecting a process of stress sensitization. However, there is little longitudinal research to clarify how the development of these systems over time relates to activation during acute stress, and how aspects of such activation map onto internalizing symptoms. We investigated children's (n = 107) diurnal hypothalamic-pituitary-adrenal activity via salivary cortisol (morning and evening levels) across 29 assessments spanning 6+ years, and related longitudinal patterns to acute stress responses at the end of this period (age 9-10). Associations with child psychiatric symptoms at age 10 were also examined to determine internalizing risk profiles. Increasing morning cortisol levels across assessments predicted less of a cortisol decline following interpersonal stress at age 9, and higher cortisol levels during performance stress at age 10. These same profiles of high and/or sustained cortisol elevation during psychosocial stress were associated with child anxiety symptoms. Results suggest developmental sensitization to stress-reflected in rising morning cortisol and eventual hyperactivation during acute stress exposure-may distinguish children at risk for internalizing disorders.

Trait and state rumination interact to prolong cortisol activation to psychosocial stress in females

There is a growing realization that cognitive processes associated with stress coping, such as rumination and distraction, can impact the hypothalamic-pituitary-adrenal-axis (HPA-axis). Yet, little is known about what aspects of the HPA-axis stress response (rate of activation, duration of activation, rate of recovery) is impacted by such cognitive processes. This study examines the impact of both ruminative trait tendencies and experimentally induced rumination on salivary cortisol responses to a social evaluative stress task. Participants (n=71) were exposed to the Trier Social Stress Test (TSST) and were then randomized to complete either a rumination or distraction task. Trait rumination was also assessed at baseline. Results showed no main effects of either trait rumination or experimental condition, but they interacted to predict the cortisol response. Specifically, participants high in trait rumination had prolonged duration of cortisol activation in the rumination condition, compared to those in the distraction condition. In contrast, cortisol responses of participants with low trait rumination did not differ by condition. Notably, our interaction effect was only significant in females. Our findings highlight the complex relationship between rumination and HPA-axis activity, suggesting an interaction of trait and state rumination in shaping HPA-axis responses to stress, and call attention to sex differences in this relationship.

The Trier Social Stress Test: Principles and practice

Researchers interested in the neurobiology of the acute stress response in humans require a valid and reliable acute stressor that can be used under experimental conditions. The Trier Social Stress Test (TSST) provides such a testing platform. It induces stress by requiring participants to make an interview-style presentation, followed by a surprise mental arithmetic test, in front of an interview panel who do not provide feedback or encouragement. In this review, we outline the methodology of the TSST, and discuss key findings under conditions of health and stress-related disorder. The TSST has unveiled differences in males and females, as well as different age groups, in their neurobiological response to acute stress. The TSST has also deepened our understanding of how genotype may moderate the cognitive neurobiology of acute stress, and exciting new inroads have been made in understanding epigenetic contributions to the biological regulation of the acute stress response using the TSST. A number of innovative adaptations have been developed which allow for the TSST to be used in group settings, with children, in combination with brain imaging, and with virtual committees. Future applications may incorporate the emerging links between the gut microbiome and the stress response. Future research should also maximise use of behavioural data generated by the TSST. Alternative acute stress paradigms may have utility over the TSST in certain situations, such as those that require repeat testing. Nonetheless, we expect that the TSST remains the gold standard for examining the cognitive neurobiology of acute stress in humans.

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The TSST is the human experimental gold standard for evaluating the neurobiology of acute stress.

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The HPA axis response to the TSST is higher in males and lower in older adults.

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Genotype and epigenetic factors moderate the neurobiological response to the TSST.

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Multiple adaptations of the TSST are available for different testing contexts.

The CIRCORT database: Reference ranges and seasonal changes in diurnal salivary cortisol derived from a meta-dataset comprised of 15 field studies

Diurnal salivary cortisol profiles are valuable indicators of adrenocortical functioning in epidemiological research and clinical practice. However, normative reference values derived from a large number of participants and across a wide age range are still missing. To fill this gap, data were compiled from 15 independently conducted field studies with a total of 104,623 salivary cortisol samples obtained from 18,698 unselected individuals (mean age: 48.3 years, age range: 0.5-98.5 years, 39% females). Besides providing a descriptive analysis of the complete dataset, we also performed mixed-effects growth curve modeling of diurnal salivary cortisol (i.e., 1-16h after awakening). Cortisol decreased significantly across the day and was influenced by both, age and sex. Intriguingly, we also found a pronounced impact of sampling season with elevated diurnal cortisol in spring and decreased levels in autumn. However, the majority of variance was accounted for by between-participant and between-study variance components. Based on these analyses, reference ranges (LC/MS-MS calibrated) for cortisol concentrations in saliva were derived for different times across the day, with more specific reference ranges generated for males and females in different age categories. This integrative summary provides important reference values on salivary cortisol to aid basic scientists and clinicians in interpreting deviations from the normal diurnal cycle.