Stress revisited: a critical evaluation of the stress concept

The construct validity of screening questions for kinesiophobia, pain catastrophizing, depression, and stress in patients with (sub-)acute non-traumatic neck pain

BACKGROUND

Neck pain is common and may transition from acute to chronic, often influenced by psychological factors like kinesiophobia, pain catastrophizing, depression, and stress. Early screening for these factors in patients with (sub-)acute neck pain is crucial to prevent chronicity.

OBJECTIVES

To examine the construct validity and internal consistency of screening questions for kinesiophobia, pain catastrophizing, depression, and stress in Dutch patients with (sub-)acute, non-traumatic neck pain.

DESIGN

Cross sectional study.

METHOD

Hypotheses were formulated for convergent and divergent validity. Screening questions were compared with established questionnaires: the Tampa Scale for Kinesiophobia (TSK-11) for kinesiophobia, the Pain Catastrophizing Scale (PCS-6) for pain catastrophizing, and the Depression, Anxiety, and Stress Scale (DASS-21) for depression and stress. When strong convergent validity (r ≥ 0.7) was observed, internal consistency was assessed.

RESULTS

Moderate correlations were observed for kinesiophobia (r = 0.526, TSK-11), depression (r = 0.660 DASS-21 depression), and stress (r = 0.506. DASS-21 distress). Pain catastrophizing showed a strong correlation with the PCS-6 (r = 0.771). Divergent validity was supported by correlations ≤0.5 with unrelated constructs for kinesiophobia, pain catastrophizing, and stress, but not for depression. Internal consistency for pain catastrophizing was 0.692. Scatterplots showed wide dispersion for kinesiophobia and stress. For pain catastrophizing, the scatterplot revealed that low screening scores were associated with high reference standard scores.

CONCLUSIONS

Investigating the complex constructs of kinesiophobia, pain catastrophizing, depression and stress with one or two questions cannot currently be recommended. Further research is needed to confirm the ability to screen for psychological constructs.

The city and forest bird flock together in a common garden: genetic and environmental effects drive urban phenotypic divergence

Urban phenotypic divergences are documented across diverse taxa, but the underlying genetic and environmental drivers behind these phenotypic changes are unknown in most wild urban systems. We conduct a common garden (CG) experiment using great tit (Parus major) eggs collected along an urbanization gradient to: (1) determine whether documented morphological, physiological, and behavioral shifts in wild urban great tits are maintained in birds from urban and forest origins reared in a CG (N = 73) and (2) evaluate how different sources of genetic, early maternal investment, and later environmental variation contributed to trait variation in the experiment. In line with the phenotypic divergence in the wild, CG birds from urban origins had faster breath rates (i.e., higher stress response) and were smaller than birds from forest origins, while wild differences in aggression and exploration were not maintained in the experiment. Differences between individuals (genetic and environmentally induced) explained the most trait variation, while variation among foster nests and captive social groups was limited. Our results provide trait-specific evidence of evolution in an urban species where genetic change likely underlies urban differences in morphology and stress physiology but that urban behavioral divergences are more strongly driven by plasticity.

Effects of acute stress exposure on pain sensitivity: the role of individual stress responsiveness and orientation to pain and stress

ABSTRACT

Acute stress exposure has been reported to result in stress-induced hypoalgesia (SI-hypo), hyperalgesia (SI-hyper), or no response (SI-NR). The inconsistency may stem from individual variability in acute stress response and/or individual orientation to stress and pain, factors not commonly examined. We aimed to identify patterns of SI-hypo and SI-hyper, their relation to stress responsiveness, and the moderating effects of stress and pain orientations. Healthy participants (n = 133) were exposed to acute stress via the Montreal Imaging Stress Task (MIST). Heat-pain threshold (HPT) was measured before and after the MIST. Changes in state anxiety pre-post MIST indicated stress responsiveness, and stress and pain orientations were evaluated via Global Perceived Stress (GPS) and Fear of Pain (FOP), respectively. Autonomic variables and salivary cortisol were examined for manipulation check. The MIST induced three pattens of effect on HPT: 27.8% of participants exhibited SI-hypo, 24.8% exhibited SI-hyper, and 47.4% SI-NR. Higher stress responsiveness was associated with greater HPT change. FOP and GPS significantly moderated the association between stress responsiveness and HPT change; the higher the stress response, the greater SI-hypo among individuals with low FOP and among individuals with high GPS. Furthermore, the higher the stress response, the greater SI-hyper among individuals with high FOP. Thus, individual variability in the effects of stress on pain sensitivity may be conditioned by stress responsiveness, and by stress and pain orientations. As increased distress can contribute to, and exacerbate, chronic pain, FOP and GPS may serve as treatment targets for the prevention and amelioration of chronic pain.

Inducing and measuring positive affective state in domesticated equines: A Delphi consultation

Over the last twenty years the definition of good animal welfare has advanced from the 'absence of negative welfare states' to the aim of identifying the presence of positive welfare states; however, research on positive animal welfare is relatively new. Consequently, through expert consultation, this study aimed to synthesise knowledge regarding domesticated equine emotional state, specifically methods to induce and measure positive affective states, which could be of significant benefit to equine welfare across sectors. A Delphi consultation of experts in the field of equine behaviour, welfare and affective state was undertaken to derive consensus agreement on definitions used when considering positive affective state in equines and methods suitable for inducing and measuring these states within experimental investigations. Ninety-three international experts participated in a robust three-round Delphi consultation with data gathered analysed qualitatively (thematic analysis) and quantitatively (ranking data, consensus benchmarks and Content Validity Index (CVI) / Content Validity Ratio (CVR) analyses). Retention rates were high (78 %), and consensus (minimum 70 % agreement) was reached within Round three of the consultation. Nineteen methods for inducing positive affect reached consensus (provision of high value food, an affiliative companion and a substrate to roll in where the highest ranked), and twelve behavioural (assessment of body language, facial actions and horse-horse interactions were ranked highest) and three physiological (evaluation of heart rate, heart rate variability and respiratory rate) variables for measuring positive affect also reached consensus. This consultation highlights several important considerations surrounding the induction and measurement of positive affective state in equines, including consideration of the individual's personality and individual preference within any measures of affective state. We therefore recommend that establishing individual preference should be a prerequisite of research into positive affective states. It is anticipated that the results of this study can be used to provide new direction for research on positive affective states by providing expert agreed methods and measures for policy and practice through expert agreed approaches to induce positive affect in horses.

Towards a scientific definition of animal emotions: Integrating innate, appraisal, and network mechanisms

This paper introduces a mechanistic framework for understanding animal emotions, which is designed for biologists studying animal behavior and welfare. Researchers often examine emotions-short-term valenced experiences-through behavioral, somatic, and cognitive indicators. However, proposed indicators are often ambivalent (emerge in contexts with opposing emotional valence) or undetermined (arise in both affective and non-affective processes). To ground hypothesis formulation regarding animal emotions on a better foundation, the paper advocates for building on what we know regarding the mechanisms of human emotions-the behavioral rules that transform sensory input into motor output during emotional episodes. In particular, it integrates key assumptions from three dominant psychological theories of emotion-innate, appraisal, and network theories-into a single framework and argues that this can serve as a common ground to transfer insights from human to animal emotion research. Additionally, the paper tackles the question of how emotions relate to closely linked processes such as decision-making, distinguishing between parallel architecture models-where emotions and decision-making processes interact but remain distinct-and unified models-where affective states are conceived as integral to goal-oriented processes. Finally, we discuss how our mechanistic proposal can help us address four key questions in animal emotion research: Do animals experience emotions? If so, which animals experience emotions? Which emotions do they experience? And how do these emotions compare to human emotions? The paper concludes by emphasizing the need for further empirical research on the mechanisms of animal emotions and their distinction from other processes.

Contributions of Health Psychology to Climate Change: A Review

Climate change poses a significant threat to human health, necessitating interdisciplinary approaches to mitigate its effects. Health psychology, with its focus on behavior change and well-being, is uniquely positioned to contribute to climate action. This review examines how health psychology can address climate-related challenges, emphasizing psychological responses to environmental stressors, behavior modification strategies, and public health interventions. The findings indicate that climate change functions as a psychological stressor, contributing to anxiety, depression, and eco-distress. Additionally, behavioral science insights are underutilized in climate governance, despite their potential to drive sustainable actions. Health psychology can enhance climate adaptation by promoting pro-environmental behaviors, fostering resilience, and integrating psychological well-being into policy frameworks. However, barriers such as limited interdisciplinary collaboration and insufficient emphasis on systemic change hinder progress. To maximize impact, health psychologists must engage in climate governance, advocate for policy integration, and address both individual and collective behavior change. Future research should explore the intersection of mental health, climate resilience, and behavior adaptation to develop comprehensive strategies for tackling climate change. This review underscores the urgent need for health psychology to play a more active role in shaping climate policy and fostering sustainable, health-promoting behaviors.

Investigating the interplay of stressors and health in horses through fecal cortisol metabolite analysis

Introduction

Horses are highly sensitive to stress, which can affect their wellbeing and lead to various health issues. Effective and objective stress assessment is therefore crucial for improving their care and management. The production of the glucocorticoid cortisol is increased in response to stressful stimuli and its metabolites can be measured non-invasively in feces. Therefore, this study aimed to explore the impact of different environmental and physiological stressors on fecal cortisol metabolite (FCM) concentrations in horses, with a particular focus on the relationship between stress, health, and welfare. We hypothesized that increased FCM levels may be indicative of disease and thus improve early detection and subsequent intervention.

Methods

Fresh fecal samples of N = 41 horses (20 geldings and 21 mares) from the same herd were collected once weekly for 1 year. Horses had been housed in the same stable for at least a month and were accustomed to the habitat, daily routine, and social groups. Environmental conditions, health data, and potentially stressful events were recorded. Fecal concentrations of 11,17-dioxoandrostanes were measured via 11-oxoetiocholanolone enzyme immunoassay.

Results

We showed stable baseline FCM concentrations of 6.3 ng/g feces (range 0.6-28.1 ng/g feces). During the summer months, median FCM concentrations increased significantly (p < 0.05; One Way RM ANOVA), and this increase correlated with higher ambient temperatures (p < 0.0001, adj r 2 = 0.669, Pearson Product Moment correlation). Additionally, other factors such as breed, coat color, and housing conditions influenced the FCM concentrations. Stressful events, such as riding exams and some painful conditions, also resulted in elevated FCM levels, although the magnitude of these responses varied across individual horses. However, not all diseases were associated with increased FCMs.

Discussion

Our findings emphasize the complexity of the hypothalamic-pituitary-adrenal axis in horses, suggesting that while high FCM levels can indicate stress, they may not be reliable biomarkers for early disease detection. Particularly in the light of climate change, the impact of heat stress in the summer months should not be neglected and measures to improve the housing conditions accordingly should become an essential part of equine health management.

The Moderating Effect of Coping on Stress and Childhood Obesity-Related Health Behaviors among Non-Hispanic Black Caregivers

Child health behaviors and weight status may be affected by caregivers' perception and experience of stress. However, little is known about the influence of caregiver coping strategies on childhood overweight and obesity, particularly among non-Hispanic Black caregivers. This study examined associations among specific caregiver stress types (i.e., general, parenting, race-related), child weight status, and health-related behaviors (i.e., intake of fruits and vegetables, consumption of fast food, engagement in physical activity) as well as the moderating effect of caregiver coping strategies. In addition to general coping, the study examined the role of religious coping. This cross-sectional study included 157 non-Hispanic Black caregiver and child (aged 3-7 years) dyads; all caregivers identified as Christian Protestant. Logistic regression models were fit to explore the associations among caregiver stress and child outcomes and to investigate moderation effects of caregiver coping. Models were adjusted for sociodemographic covariates. Association between parenting stress and child weight status was significantly moderated by acceptance coping while the relationship between general stress and child sugary drink intake was moderated by emotional coping. The combination of three stress types was significantly associated with increased child fast food intake. Future research should examine specific coping strategies to address varying levels and types of stress experienced by caregivers from minoritized backgrounds.

Long term exposure to multiple environmental stressors induces mitochondrial dynamics imbalance in testis: Insights from metabolomics and transcriptomics

Long-term exposure to adverse environment stressors (e.g. noise pollution, temperature, and crowding) impaired human health. However, research on the toxic effects of adverse environmental stressors on the male reproductive system is limited. This study employed integrated phenomics, metabolomics, and transcriptomics to investigate physiological disturbances in the testis of mice exposed to multiple adverse environmental stressors for two months. Phenotypic studies indicated that long-term environmental stimuli resulted in significant damage to the blood-testis barrier (BTB) and testes, evidenced by reduced testicular index, disrupted testicular tissue structure, abnormal tight junction protein expression, and spermatozoa abnormalities. Comprehensive multi-omics analysis revealed that long-term exposure to environmental stressors disrupted the BTB and testes, which was associated with mitochondrial metabolism disorders, including oxidative phosphorylation and fatty acid beta-oxidation, as well as glutathione and lipid metabolism alterations. Among these dysregulated pathways, significant alterations were observed in the critical regulators of mitochondrial fusion (MFN2) and fission (DRP1) within the BTB. Specifically, corticosterone treatment decreased tight junction protein expression, increased reactive oxygen species (ROS) levels, and impaired mitochondrial morphology and function, as evidenced by reduced mitochondrial membrane potential, elevated calcium ion concentration, and shortened mitochondrial length and network in vitro. Moreover, inhibiting DRP1 with Mdivi-1 or overexpressing MFN2 mitigated the corticosterone-induced reduction of tight junctions and mitochondrial dysregulation in TM4 cells. Collectively, maintaining mitochondrial homeostasis emerges as a promising strategy to alleviate the BTB and testicular injury induced by long-term exposure to multiple environmental stressors.

Does seasonal variation in the corticosterone response affect the nutritional ecology of a free-ranging lizard?

Challenging events in the environment that are both predictable (e.g. seasonal patterns in breeding activities) and unpredictable (e.g. predator encounter) are known to induce a glucocorticoid response that facilitates metabolic requirements during the challenge. Given its role in mobilizing energy, glucocorticoid levels can influence the nutritional ecology of an individual by shifting dietary intake or retention patterns, but this relationship has not been tested in free-ranging vertebrates. Using a tropical lizard species (Psammophilus dorsalis) as a model system, we tested whether the elemental composition of dietary intake and excretion (faecal samples) varies with stress-induced corticosterone levels in males and females across different seasons. From free-ranging lizards in the wild, we measured levels of stress-induced corticosterone and glucose in blood and determined diet composition from gut-flushing. Elemental composition of the diet was determined by analysing the carbon and nitrogen content of identified prey Orders caught from the wild. We also collected faecal samples and estimated their elemental composition. We found that stress-induced corticosterone levels varied across seasons, with the lowest levels during the breeding season for both males and females. Despite high variation in corticosterone responsiveness, lizards did not shift the elemental composition of their diets and maintained an intake carbon:nitrogen ratio of 4.56. We did, however, find a negative correlation between stress-induced corticosterone levels and faecal elemental composition, suggesting selective retention of both carbon and nitrogen in individuals that have higher corticosterone responsiveness. This study highlights the interplay between corticosterone responsiveness and nutritional ecology, challenging the existing links in literature and illustrating how free-ranging animals, such as lizards, adjust the elemental composition of excretion and not dietary intakes as a potential strategy to modulate natural physiological and ecological challenges.

Resilience as a mediator between emotional intelligence (EI) and perceived stress among young adults in Malaysia

Stress encompasses a complex interplay of physical, mental, and emotional responses triggered by demanding or challenging circumstances. Perceived stress refers to the subjective assessment of stress levels by an individual. As existing research indicates, this subjective experience of stress is intricately connected to emotional intelligence (EI) and resilience. Aligned with this knowledge, the present study aims to contribute to the existing body of knowledge by exploring the mediating role of resilience in the relationship between EI and perceived stress levels. A cross-sectional online study was conducted involving 207 young adults from Malaysia (152 females and 55 males). Sex (gender) differences in perceived stress levels were evaluated using t-tests, revealing that females reported higher levels of perceived stress. Interestingly, EI did not exhibit an age-related increase. Results confirmed the predictive relationships among EI, resilience, and perceived stress. Mediational analyses uncovered a full mediation model, illustrating that resilience is pivotal in mediating the relationship between EI and perceived stress. The findings strongly indicate that individuals with elevated EI levels are more likely to possess higher resilience, resulting in lower perceived stress levels. These results underscore the importance of interventions targeting EI and resilience enhancement, as such interventions hold promise for positively impacting the mental well-being of young adults.

Identifying Cardiovascular Risk by Nonlinear Heart Rate Dynamics Analysis: Translational Biomarker from Mice to Humans

BACKGROUND

The beat-by-beat fluctuation of heart rate (HR) in its temporal sequence (HR dynamics) provides information on HR regulation by the autonomic nervous system (ANS) and its dysregulation in pathological states. Commonly, linear analyses of HR and its variability (HRV) are used to draw conclusions about pathological states despite clear statistical and translational limitations.

OBJECTIVE

The main aim of this study was to compare linear and nonlinear HR measures, including detrended fluctuation analysis (DFA), based on ECG recordings by radiotelemetry in C57BL/6N mice to identify pathological HR dynamics.

METHODS

We investigated different behavioral and a wide range of pharmacological interventions which alter ANS regulation through various peripheral and/or central mechanisms including receptors implicated in psychiatric disorders. This spectrum of interventions served as a reference system for comparison of linear and nonlinear HR measures to identify pathological states.

RESULTS

Physiological HR dynamics constitute a self-similar, scale-invariant, fractal process with persistent intrinsic long-range correlations resulting in physiological DFA scaling coefficients of α~1. Strongly altered DFA scaling coefficients (α ≠ 1) indicate pathological states of HR dynamics as elicited by (1) parasympathetic blockade, (2) parasympathetic overactivation and (3) sympathetic overactivation but not inhibition. The DFA scaling coefficients are identical in mice and humans under physiological conditions with identical pathological states by defined pharmacological interventions.

CONCLUSIONS

Here, we show the importance of tonic vagal function for physiological HR dynamics in mice, as reported in humans. Unlike linear measures, DFA provides an important translational measure that reliably identifies pathological HR dynamics based on altered ANS control by pharmacological interventions. Central ANS dysregulation represents a likely mechanism of increased cardiac mortality in psychiatric disorders.

Approaching pediatric mental health screening and care in immigration detention

Children held in US immigration detention facilities often arrive with significant mental health conditions requiring prompt attention. Despite the abundance of literature highlighting the need for adequate mental health care in migrant children, there is a chasm between the care offered to detained migrant children in the US and the minimum standards of healthcare in the US. This discrepancy is fueled by the mandate of Immigration and Customs Enforcement (ICE), which prioritizes immigration enforcement rather than the health and well-being of detained children. The tension between the existing ICE's enforcement mandate and the internationally recognized right to health care for children results in inadequate mental health care, causing long-term harm. We highlight current pediatric mental health screening and treatment practices in immigration detention facilities, exploring the role of ICE and child protection frameworks. We conclude by providing policy recommendations to improve mental health care in US-based detention facilities.

Validation of two enzyme immunoassays for non-invasive glucocorticoid measurement in a lacertid lizard (Podarcis muralis): Effects of pharmacological and biological stimuli on faecal corticosterone metabolites and behaviour

The assessment of stress-related hormone levels using non-invasive methods has gained popularity in mammal and bird welfare, yet its application in reptiles remains limited. Particularly, the exploration of physiological measures such as faecal corticosterone metabolites (FCMs) for reptilian welfare has scarcely been explored. This study aims to validate two enzyme immunoassays (5α-pregnane-3ß,11ß,21-triol-20-one and 11-oxoaetiocholanolone EIA) for monitoring FCM levels in the European common wall lizard (Podarcis muralis). We collected daily faecal samples before (baseline) and after (post-treatment phase) inducing elevated corticosterone levels using transdermal administration of corticosterone (pharmacological treatment) and handling/confinement (biological treatment). We also conducted daily behavioural observations to explore the relationship between stress-related corticosterone changes and behaviour. Although treatments induced significant increases in FCM levels, the effect was much larger in the pharmacological one. Transdermal corticosterone induced a cumulative increase in FCMs over the treatment period, with a higher response observed in females. In contrast, the biological treatment yielded smaller FCM peaks, with no significant sex differences. Overall, 5α-pregnane-3ß,11ß,21-triol-20-one EIA appeared to be more sensitive in detecting these effects. Regarding lizard behaviour, both treatments led to increased hiding and decreased basking compared to baseline. The effects were more pronounced in animals subjected to handling/confinement, despite smaller FCM increases. Our results confirm the suitability of an EIA for monitoring FCMs in both male and female common wall lizards and provide insights into the complexities of using integrated approaches to assess stress, highlighting the need for further research on direct measures to evaluate reptile welfare.

Predictors of stress among nucleic acid sampling support nurses (NASSNs) during the COVID-19 pandemic

BACKGROUND

The COVID-19 pandemic has forced nucleic acid detection to be essential for prevention and control. The psychological and physical health of healthcare staff who conducted nucleic acid sampling (NAS) should be paid attention to. This study aims to investigate the status and explore the predictors of stress among nucleic acid sampling support nurses (NASSNs) by an online survey.

MATERIAL AND METHODS

Totally 388 NASSNs were recruited through cluster random sampling for the research. An online cross-sectional survey with structured questionnaires was used, including socio-demographic information, the stressor scale of nucleic acid sampling nurses (SSNASN), and the challenge-hindrance stress scale (CHSS). T-tests, ANOVA, and multivariable linear regression model were used to analyze data.

RESULTS

A total of 324 NASSNs filled out questionnaires online with a response rate of 83.51%. NASSNs had an overall mean score of (2.199 ± 0.917) for challenge stress and (2.014 ± 0.805) for hindrance stress. The item "the amount of responsibility I have" scored highest in the challenge stress dimension, while "the lack of job security I have" scored highest in the hindrance stress dimension. The predictors of challenge and hindrance stress include concern about the preparedness of NASSNs and their families, working environment, and competence of emergency disposal. An additional socio-demographic predictor of challenge stress was motivation, while that of hindrance stress was longer nursing experiences.

CONCLUSIONS

During the COVID-19 pandemic, stress among NASSNs was moderately low. The factors detected to be predictors of stress include motivation, nursing experiences, concern about the preparedness of NASSNs and their families, working environment, and competence in emergency disposal. Therefore, in advance of responding to a public health event, we recommend that subsequent short-term psychological counseling be given to healthcare workers and accompanying psychological counseling be provided to prevent the emergence of mental health problems thereafter.

Building Resilience: The Stress Response as a Driving Force for Neuroplasticity and Adaptation

People exhibit an extraordinary capacity to adjust to stressful situations. Here, we argue that the acute stress response is a major driving force behind this adaptive process. In addition to immediately freeing energy reserves, facilitating a rapid and robust neurocognitive response, and helping to reinstate homeostasis, the stress response also critically regulates neuroplasticity. Therefore, understanding the healthy acute stress response is crucial for understanding stress resilience-the maintenance or rapid recovery of mental health during and after times of adversity. Contemporary resilience research differentiates between resilience factors and resilience mechanisms. Resilience factors refer to a broad array of social, psychological, or biological variables that are stable but potentially malleable and predict resilient outcomes. In contrast, resilience mechanisms refer to proximate mechanisms activated during acute stress that enable individuals to effectively navigate immediate challenges. In this article, we review literature related to how neurotransmitter and hormonal changes during acute stress regulate the activation of resilience mechanisms. We integrate literature on the timing-dependent and neuromodulator-specific regulation of neurocognition, episodic memory, and behavioral and motivational control, highlighting the distinct and often synergistic roles of catecholamines (dopamine and norepinephrine) and glucocorticoids. We conclude that stress resilience is bolstered by improved future predictions and the success-based reinforcement of effective coping strategies during acute stress. The resulting generalized memories of success, controllability, and safety constitute beneficial plasticity that lastingly improves self-control under stress. Insight into such mechanisms of resilience is critical for the development of novel interventions focused on prevention rather than treatment of stress-related disorders.

Assessing operator stress in collaborative robotics: A multimodal approach

In the era of Industry 4.0, the study of Human-Robot Collaboration (HRC) in advancing modern manufacturing and automation is paramount. An operator approaching a collaborative robot (cobot) may have feelings of distrust, and experience discomfort and stress, especially during the early stages of training. Human factors cannot be neglected: for efficient implementation, the complex psycho-physiological state and responses of the operator must be taken into consideration. In this study, volunteers were asked to carry out a set of cobot programming tasks, while several physiological signals, such as electroencephalogram (EEG), electrocardiogram (ECG), Galvanic skin response (GSR), and facial expressions were recorded. In addition, a subjective questionnaire (NASA-TLX) was administered at the end, to assess if the derived physiological parameters are related to the subjective perception of stress. Parameters exhibiting a higher degree of alignment with subjective perception are mean Theta (76.67%), Alpha (70.53%) and Beta (67.65%) power extracted from EEG, recovery time (72.86%) and rise time (71.43%) extracted from GSR and heart rate variability (HRV) metrics PNN25 (71.58%), SDNN (70.53%), PNN50 (68.95%) and RMSSD (66.84%). Parameters extracted from raw RR Intervals appear to be more variable and less accurate (42.11%) so as recorded emotions (51.43%).

Unconscious will as a neurobehavioral mechanism against adversity

Incentive salience theory both explains the directional component of motivation (in terms of cue attraction or "wanting") and its energetic component, as a function of the strength of cue attraction. This theory characterizes cue- and reward-triggered approach behavior. But it does not tell us how behavior can show enhanced vigor under reward uncertainty, when cues are inconsistent or resources hidden. Reinforcement theory is also ineffective in explaining enhanced vigor in case reward expectation is low or nil. This paper provides a neurobehavioral interpretation of effort in situations of adversity (which always include some uncertainty about outcomes) that is complementary to the attribution of incentive salience to environmental cues. It is argued that manageable environmental challenges activate an unconscious process of self-determination to achieve "wanted" actions. This unconscious process is referred to as incentive effort, which involves the hypothalamo-pituitary-adrenal (HPA) axis, noradrenaline, as well as striatal dopamine. Concretely, HPA-induced dopamine release would have the function to make effort-or effortful actions-"wanted" in a challenging context, in which the environmental cues are poorly predictive of reward-i.e., unattractive. Stress would only emerge in the presence of unmanageable challenges. It is hypothesized that incentive effort is the core psychological basis of will-and is, for this reason, termed "willing."

The mouse Social Frailty Index (mSFI): a novel behavioral assessment for impaired social functioning in aging mice

Various approaches exist to quantify the aging process and estimate biological age on an individual level. Frailty indices based on an age-related accumulation of physical deficits have been developed for human use and translated into mouse models. However, declines observed in aging are not limited to physical functioning but also involve social capabilities. The concept of "social frailty" has been recently introduced into human literature, but no index of social frailty exists for laboratory mice yet. To fill this gap, we developed a mouse Social Frailty Index (mSFI) consisting of seven distinct assays designed to quantify social functioning which is relatively simple to execute and is minimally invasive. Application of the mSFI in group-housed male C57BL/6 mice demonstrated a progressively elevated levels of social frailty through the lifespan. Conversely, group-housed females C57BL/6 mice manifested social frailty only at a very old age. Female mice also showed significantly lower mSFI score from 10 months of age onward when compared to males. We also applied the mSFI in male C57BL/6 mice under chronic subordination stress and in chronic isolation, both of which induced larger increases in social frailty compared to age-matched group-housed males. Lastly, we show that the mSFI is enhanced in mouse models that show accelerated biological aging such as progeroid Ercc1-/Δ and Xpg-/- mice of both sexes compared to age matched littermate wild types. In summary, the mSFI represents a novel index to quantify trajectories of biological aging in mice and may help elucidate links between impaired social behavior and the aging process.

Using Faecal Cortisol Metabolites to Assess Adrenocortical Activity in Wild-Living Alpine Marmot Marmota marmota: A Biological Validation Experiment

Faecal cortisol/corticosterone metabolites (FCMs) have become increasingly popular as an easy-to-sample, non-invasive and feedback-free alternative to assess glucocorticoid (GC) levels, key components of the neuroendocrine stress response and other physiological processes. While FCMs can be a powerful aid, for instance, for gaining insights into ecological and evolutionary processes, as well as to assess animal welfare or impacts of anthropogenic stressors on wildlife populations, this method comes with specific challenges. Because GCs are heavily metabolised before excretion, it is critical to validate the enzyme immunoassays (EIAs) used to measure FCMs. Additionally, because species may differ in metabolite profiles, assay validation must be performed separately for each focal species. Despite this, the use of unvalidated assays remains widespread. We performed a biological validation experiment to test a set of EIAs to measure FCMs and adrenocortical activity in free-living Alpine marmots Marmot marmota. We capitalised on capture and handling as part of a relocation project of marmots under the assumption that capture, and handling represent a stressful event and tracked changes in FCM levels over the following 48 h. Faeces samples collected at capture were assumed to return baseline FCM levels. Of the three EIAs tested, only the 11-oxoetiocholanolone '72T' EIA detected an increase in FCM levels about 18 h after capture. This result paves the way for future studies using FCMs to investigate the adrenocortical activity in this species.

Predictive biomarkers of performance under stress: a two-phase study protocol to develop a wearable monitoring system

Understanding and predicting individual responses to common stressors is essential for optimising performance in high-stress environments. This article outlines a protocol for a study to identify biomarkers that predict performance under heat, musculoskeletal, psychosocial and sleep stress, for future integration into a wearable sensor system. In Phase I, healthy adults aged between 18 and 45 years (n=104) will be recruited for an intervention trial that involves exposure to one of the four stressors: heat, musculoskeletal, psychosocial or sleep deprivation. Biomarkers will be identified from molecular markers in biological samples (eg, blood, saliva, sweat and stool), physiological measures and psychological assessments to predict cognitive and physical performance under stress. A within-subjects design will determine changes in molecular and non-molecular markers before and after stress exposure. In Phase II, we will use the biomarkers identified in Phase I to develop a wearable sensor to predict and monitor human performance under stress.

Chronic social stress induces p16-mediated senescent cell accumulation in mice

Life stress can shorten lifespan and increase risk for aging-related diseases, but the biology underlying this phenomenon remains unclear. Here we assessed the effect of chronic stress on cellular senescence-a hallmark of aging. Exposure to restraint stress, a psychological non-social stress model, increased p21Cip1 exclusively in the brains of male, but not female mice, and in a p16Ink4a-independent manner. Conversely, exposure to chronic subordination stress (only males were tested) increased key senescent cell markers in peripheral blood mononuclear cells, adipose tissue and brain, in a p16Ink4a-dependent manner. p16Ink4a-positive cells in the brain of chronic subordination stress-exposed mice were primarily hippocampal and cortical neurons with evidence of DNA damage that could be reduced by p16Ink4a cell clearance. Clearance of p16Ink4a-positive cells was not sufficient to ameliorate the adverse effects of social stress on measured metrics of healthspan. Overall, our findings indicate that social stress induces an organ-specific and p16Ink4a-dependent accumulation of senescent cells, illuminating a fundamental way by which the social environment can contribute to aging.

Emotion Regulation Under Stress: A Social Processing and Memory Perspective

Research on emotion regulation often focuses on cognitively effortful self-regulation strategies, but exposure to stress has been shown to interfere with the underlying mechanisms supporting such processes. Understanding alternative strategies that potentially bolster emotion regulation under stress is an important topic of investigation. Two potential alternatives involve everyday occurrences of social processing and memory recall. Social support and past emotional experiences may help in guiding us toward appropriate neurophysiological responses through overlapping circuitry with stress and reward systems, while also buttressing cognitive regulation strategies by expanding one's perspective and allowing multiple opportunities to regulate retrospectively. In recognition that ongoing social and emotional events are often at the beginning of a cascade of both emotion regulation and memory processes, this chapter focuses on the emerging role of social relationships and autobiographical memory recall in regulating emotions under stress, highlighting opportunities and challenges associated with this process.

A Systematic Review of Theories of Stress as a Predictor of Intimate Partner Violence

Literature on stress and intimate partner violence (IPV) has primarily focused on stress as an outcome of women's experience of IPV. However, stress may also be a predictor of male-perpetrated IPV. To improve our understanding of how theoretical approaches to stress have been applied to IPV research, we conducted a sub-analysis of a broader systematic review to identify published literature that examines theoretical approaches to stress as a predictor of male-perpetrated IPV. We conducted a search of nine electronic databases and assessed title/abstract and full texts according to pre-defined inclusion and exclusion criteria. Two reviewers categorized included studies into different theoretical groupings and sub-groupings. Data were extracted according to a data extraction template developed for the review, establishing consistency in a pilot data extraction phase. The review identified 27 articles that addressed the following theories of stress: general stress theory, life course theory, occupational stress theory, vulnerability theory, and family stress theory. Each of these sub-theories focuses on different forms of stress, for example, life course theory specifically focuses on stressful early life experiences, including adverse childhood events, whereas occupational stress theory focuses on workplace-related stressors that may result in increased male-perpetrated IPV. Analysis of measurement of stress variables indicated that measurement of stress varies widely across studies and primarily relies on self-reports. Consideration of stress as a predictor of IPV provides important insights into preventable and modifiable targets for intervention. Additional research on mechanisms and pathways between stress and IPV is needed.

Effect of a Broiler-Specific Light Spectrum on Growth Performance and Adrenocortical Activity in Chickens: A Pilot Study on a Commercial Farm

This study evaluated the effect of a broiler-specific light spectrum on productive performance corticosterone (fCC) and androgen dehydroepiandrosterone (fDHEA) concentrations in feathers, and glucocorticoid (GCMs) and androgen (AMs) metabolites in droppings of broilers. Two groups of female Ross 308 broilers were reared under white LED (WL, n = 9000) and broiler-specific LED (BSL, n = 9000) lights. The body weight (BW) of 150 randomly selected animals/groups was measured weekly. Droppings and feathers were collected at the end of the cycle (29 days) from 20 animals/group. The BSL group showed higher final BW than WL (1407 ± 11 vs. 1341 ± 15 g, respectively; p < 0.001) and higher indices of uniformity (76.8% vs. 61.2% animals in the 10% around the mean, respectively; p < 0.001). No difference between groups was found in fCC and fDHEA concentrations or in the fCC-fDHEA, indicating similar long-term HPA axis activity during the cycle. A higher concentration of GCMs was found in the BSL group, indicating higher glucocorticoid secretion before sampling, with neither a difference in AMs nor in GCMs-AMs. Finally, there was a positive correlation between fCC and fDHEA and between GCMs and AMs (p < 0.01). Our findings suggest that the use of broiler-specific light improved the productivity performances of chickens without long-term consequences on HPA activation. However, the results of this pilot study in a commercial farm setting must be interpreted with caution and need confirmation.

Prenatal Stress and Maternal Role in Neurodevelopment

This review summarizes recent findings on stress-related programming of brain development in utero, with an emphasis on situating findings within the mothers' broader psychosocial experiences. Meta-analyses of observational studies on prenatal stress exposure indicate the direction and size of effects on child neurodevelopment are heterogeneous across studies. Inspired by lifespan and topological frameworks of adversity, we conceptualize individual variation in mothers' lived experience during and prior to pregnancy as a key determinant of these heterogeneous effects across populations. We structure our review to discuss experiential categories that may uniquely shape the psychological and biological influence of stress on pregnant mothers and their developing children, including current socioeconomic resources, exposure to chronic and traumatic stressors, culture and historical trauma, and the contours of prenatal stress itself. We conclude by identifying next steps that hold potential to meaningfully advance the field of fetal programming.

Adult neurogenesis and the microbiota-gut-brain axis in farm animals: underestimated and understudied parameters for improving welfare in livestock farming

Welfare in commercial livestock farming is becoming increasingly important in current agriculture research. Unfortunately, there is a lack of understanding about the neuronal mechanisms that underlie well-being on an individual level. Neuroplasticity in the hippocampus, the subventricular zone (SVZ), the olfactory bulb (OB) and the hypothalamus may be essential regulatory components in the context of farm animal behaviour and welfare that may be altered by providing environmental enrichment (EE). The importance of pre-and probiotics as a form of EE and the microbiota-gut-brain axis (MGBA) has come under the spotlight in the last 20 years, particularly in the contexts of research into stress and of stress resilience. However, it could also be an important regulatory system for animal welfare in livestock farming. This review aims to present a brief overview of the effects of EE on physiology and behaviour in farm animals and briefly discusses literature on behavioural flexibility, as well as inter-individual stress-coping styles and their relationship to animal welfare. Most importantly, we will summarise the literature on different forms of neural plasticity in farm animals, focusing on neurogenesis in various relevant brain regions. Furthermore, we will provide a brief outlook connecting these forms of neuroplasticity, stress, EE, the MGBA and welfare measures in modern livestock farming, concentrating on pigs.

Peripheral Blood Leukocyte Subpopulation Changes in Reaction to an Acute Psychosocial Stressor as Compared to an Active Placebo-Stressor in Healthy Young Males: Mediating Effects of Major Stress-Reactive Endocrine Parameters

Psychosocial stress has been proposed to induce a redistribution of immune cells, but a comparison with an active placebo-psychosocial stress control condition is lacking so far. We investigated immune cell redistribution due to psychosocial stress compared to that resulting from an active placebo-psychosocial stress but otherwise identical control condition. Moreover, we tested for mediating effects of endocrine parameters and blood volume changes. The final study sample comprised 64 healthy young men who underwent either a psychosocial stress condition (Trier Social Stress Test; TSST; n = 38) or an active placebo-psychosocial stress control condition (PlacTSST; n = 26). Immune cell counts and hemoglobin, epinephrine, norepinephrine, ACTH, renin, and aldosterone levels, as well as those of saliva cortisol, were determined before and up to 30 min after the TSST/PlacTSST. The TSST induced greater increases in total leukocyte, monocyte, and lymphocyte levels as compared to the PlacTSST (p's ≤ 0.001), but in not granulocyte counts. Neutrophil granulocyte counts increased in reaction to both the TSST and PlacTSST (p's ≤ 0.001), while eosinophil and basophil granulocyte counts did not. The psychosocial stress-induced increases in immune cell counts from baseline to peak (i.e., +1 min after TSST cessation) were independently mediated by parallel increases in epinephrine (ab's ≤ -0.43; 95% CIs [LLs ≤ -0.66; ULs ≤ -0.09]). Subsequent decreases in immune cell counts from +1 min to +10 min after psychosocial stress cessation were mediated by parallel epinephrine, renin, and blood volume decreases (ab's ≥ 0.17; 95% CIs [LLs ≥ 0.02; ULs ≥ 0.35]). Our findings indicate that psychosocial stress specifically induces immune cell count increases in most leukocyte subpopulations that are not secondary to the physical or cognitive demands of the stress task. Increases in the number of circulating neutrophil granulocytes, however, are not psychosocial stress-specific and even occur in situations with a low probability of threat or harm. Our findings point to a major role of epinephrine in mediating stress-induced immune cell count increases and of epinephrine, renin, and blood volume changes in mediating subsequent immune cell count decreases from +1 min to +10 min after psychosocial stress cessation.

The effect of chronic academic stress on attentional bias towards value-associated stimuli

Individuals typically exhibit attentional bias towards stimuli that are considered valuable. This study aimed to investigate the effect of chronic academic stress on attentional bias towards value-associated stimuli. Both the stress group (preparation for a critical academic examination) and the control group performed a modified dot-probe task. Two-colour stimuli were presented simultaneously, one of which was associated with high or low monetary rewards through the value-associated training. The participants were then instructed to respond to the location of a probe dot which was presented either congruent or incongruent towards the value-associated stimuli. In the neutral condition, both stimuli were not value-associated ones. The results showed that (1) in the value-associated training task, shorter reaction times (RTs) and higher accuracies were observed for the high-value trials compared with the low-value trials in both groups, suggesting a successful association between neutral stimuli and value; (2) in the dot-probe task, the RTs were shorter for the high-/low-value congruent conditions compared with the high-/low-value incongruent conditions in both groups, suggesting an attentional bias towards value-associated stimuli; (3) compared to the control group, the stress group showed an increased disengagement (RTincongruent - RTneutral) effect but a similar orienting (RTneutral - RTcongruent) effect. These results suggested that chronic academic stress may promote attentional bias towards value-associated stimuli by impairing attentional disengagement.

Development and validation of the Epilepsy Perceived Stress Inventory for Adults (EPSI-A): A pilot study

INTRODUCTION

Stress is one of the most common trigger factors for epileptic seizures and is strongly related to clinical and emotional variables. Despite its influence in the course of the disease, there is an absence of instruments for measuring perceived stress in people with drug-resistant epilepsy. Therefore, this study develops and validates the Epilepsy Perceived Stress Inventory for Adults (EPSI-A), a self-report inventory in Spanish designed to quantify perceived chronic stress in this population.

METHOD

The sample consisted of 236 patients with drug-resistant epilepsy who underwent a neuropsychological assessment in which anxiety, depression, and quality of life were explored. In addition, from 125 patients in the sample, 9 measures of salivary cortisol were collected during the evaluation.

RESULTS

The EPSI-A consisted of 15 items, with higher scores indicating higher perceived stress. The exploratory factor analysis showed a four-factor solution: epilepsy concerns (5 items); impact on daily performance (4 items); social consequences (3 items); and epilepsy severity (3 items). These factors explained 63.3 % of the total variance. Internal consistency reliability measured with McDonald's omega and Cronbach's alpha coefficients was satisfactory, with values ≥ 0.78 (except for epilepsy severity with values of 0.59 and 0.58, respectively). Construct validity was demonstrated by its correlation with several psychological scales and clinical variables.

CONCLUSIONS

The results showed that the EPSI-A is a reliable and valid tool for assessing perceived chronic stress in people with epilepsy. Its conciseness, rapid administration time, and specificity make it an appropriate instrument for this population.

Tapping your inner psychotherapist: The effects of a growth writing for military cadets on mental health

Although growth writing has been verified to be effective in addressing psychological maladjustment through sequential shifts in emotion-processing strategies, there have been no further findings extending these preliminary observations to applications in the military field. This study aimed to investigate whether growth writing can serve as a novel intervention in enhancing the mental health of cadets. A total of 103 cadets (Sex ratio: 68.9% male, Age: 20.60± 2.16 years) participated in an 8-week writing program and were randomly assigned to either the growth writing group or the unstructured writing group. The growth writing group wrote structured narratives on the themes of exposure, devaluation, and benefit-finding for 30 minutes per week, focusing on the most stressful event in cadet lives. The unstructured writing group freely wrote about their feelings and thoughts regarding the most stressful event in cadet lives for 30 minutes every week. We found that growth writing resulted in greater benefits compared to unstructured writing, as indicated by a more significant reduction in stress, depression, anxiety, and anger, as well as a stronger increase in life satisfaction at the five-week follow-up. Moreover, significant changes were observed in stress, depression, anxiety, anger, and life satisfaction over the three assessment points among cadets in the growth writing group. Overall, the current findings highlight that the growth writing process can serve as a valuable form of self-psychotherapy for cadets who will face challenging battlefields in the future.

Could Relationship-Based Learnt Beliefs and Expectations Contribute to Physiological Vulnerability of Chronic Pain? Making a Case to Consider Attachment in Pain Research

Pain is an interpersonal and inherently social experience. Pain perception and administration of medical treatment all occur in a particular environmental and social context. Early environmental influences and early learning experiences and interactions condition the body's response to different threats (like pain), ultimately shaping the underlying neurophysiology. These early interactions and experiences also determine what situations are perceived as threatening, as well as our belief in our own ability to self-manage, and our belief in others to offer support, during perceived threats. These beliefs intrinsically drive the combination of behaviors that emerge in response to perceived threats, including pain. Such behaviors can be categorized into attachment styles. In this interdisciplinary review, we synthesize and summarize evidence from the neurobiological, psychobiological, psychosocial, and psychobehavioral fields, to describe how these beliefs are embedded in the brain's prediction models to generate a series of expectations/perceptions around the level of safety/threat in different contexts. As such, these beliefs may predict how one experiences and responds to pain, with potentially significant implications for the development and management of chronic pain. Little attention has been directed to the effect of adult attachment style on pain in research studies and in the clinical setting. Using interdisciplinary evidence, we argue why we think this interaction merits further consideration and research. PERSPECTIVE: This review explores the influence of attachment styles on pain perception, suggesting a link between social connections and chronic pain development. It aligns with recent calls to emphasize the social context in pain research and advocates for increased focus on adult attachment styles in research and clinical practice.

Assessing last month's stress levels with an automated facial behavior scan

Stress is one of the most pressing problems in society as it severely reduces the physical and mental wellbeing of people. It is therefore of great importance to accurately monitor stress levels, especially in work environments. However, contemporary stress assessments, such as questionnaires and physiological measurements, have practical limitations, mostly related to their subjective or contact-based nature. To assess stress objectively and conveniently, we developed an automated model that detects biomarkers in webcam-recorded facial behavior indicative of heightened stress levels, using computer vision, artificial intelligence, and machine learning techniques. Heart-rate induced skin pulsations and facial muscle activity were extracted from videos of 264 participants that performed an online mental capacity test under considerable time pressure. The model could successfully use these facial biomarkers to explain a significant proportion of individual differences in scores on a self-perceived stress scale. Next, we used the model to objectively score stress levels of 63 military candidates (pre-hiring) and 69 military personnel (post-hiring) that also performed the mental capacity test. Results showed that military personnel expressed facial behavior indicative of significantly higher stress levels than military candidates. This suggests that joining the military heightens overall stress levels. With this study we take the first steps towards a non-contact, automated, and objective measure of stress that is easily applicable in a variety of health and work contexts.

Crocin nano-chitosan-coated compound mitigates hippocampal blood-brain barrier disruption, anxiety, and cognitive deficits in chronic immobilization stress-induced rats

Stressful conditions can disrupt the central nervous system's normal homeostasis and physiological functions, resulting in blood-brain barrier malfunction, memory and learning impairment, anxiety, etc. Crocin is a long-investigated natural compound that has been documented to have anti-inflammation and neuroprotective effects, albeit it comes with some limitations such as low stability and bioavailability. Therefore, we aimed to overcome crocin's limitations by coating crocin with a nano-carrier (chitosan) in the chronic immobilization stress-induced rat model. Crocin was encapsulated into chitosan nanoparticles by a modified method. A total of 35 male Wistar rats were selected as our study subjects (220-250 g) which were randomly divided into 5 groups (control, stress, nanoparticle, crocin, and chitosan). Chronic immobilization stress was induced by placing rats for 2 h into a plastic bottle with specific measurements (for 14 consecutive days) to prevent animals from moving. To evaluate the memory and learning changes, we used the Barnes maze test and the Passive avoidance test followed by the evaluation of the N-methyl-D-aspartate |(NMDA) receptor subunits genes (GRIN1 and GRIN2A) expression. Anxiety levels were evaluated by elevated plus maze test. Furthermore, the changes in the expression of genes responsible for encoding the tight junction proteins of BBB including ZO1, CLDN5, and OCLN were assessed by RT-PCR. Compared to intact crocin, the administration of crocin nano-chitosan-coated compound resulted in significant improvement of specific memory and learning indicators as well as a significant reduction of anxiety levels in chronic immobilization stress-induced rats. Finally, we observed that treatment with the crocin nano-chitosan-coated compound can elevate the expression levels of the genes responsible for encoding NMDA receptor subunits, and the genes responsible for encoding the tight junction proteins of blood-brain barriers in the hippocampus.

Behavioural Monitoring Underlines Habituation to Repeated Stressor Stimuli in Farmed Gilthead Sea Bream (Sparus aurata) Reared at a High Stocking Density

A confinement stress test with 75% tank space reduction and behavioural monitoring through tri-axial accelerometers externally attached to the operculum was designed. This procedure was validated by demonstrating the less pronounced stress response in gilthead sea bream than in European sea bass (950-1200 g). Our study aimed to assess habituation to high stocking densities with such procedure in gilthead sea bream. Animals (420-450 g) were reared (June-August) in a flow-through system at two stocking densities (CTRL: 10-15 kg/m3; HD: 18-24 kg/m3), with natural photoperiod and temperature (21-29 °C), and oxygen levels at 5.2-4.2 (CTRL) and 4.2-3.2 ppm (HD). At the end, blood and muscle were sampled for haematology and transcriptomic analyses, and external tissue damage was assessed by image-based scoring. Four days later, fish underwent a 45 min confinement stress test over two consecutive days. HD fish showed reduced feed intake, growth rates and haematopoietic activity. Muscle transcriptome changes indicated a shift from systemic to local growth regulation and a primed muscle regeneration over protein accretion in HD animals with slight external injuries. After stress testing, HD fish exhibited a decreased recovery time in activity and respiration rates, which was shorter after a second stressor exposure, confirming habituation to high densities.

Application of DASS-21 in Chinese students: invariance testing and network analysis

BACKGROUND

The Depression Anxiety Stress Scale-21 Items (DASS-21) is commonly used to assess the mental health of students, but there is a need for further clarification regarding its equivalence, structure, and core items.

METHODS

We conducted a confirmatory factor analysis (CFA) on a sample of 7943 Chinese students to examine the performance of the DASS-21 and assess measurement invariance. Additionally, we utilized network analysis to investigate the structure and centrality of students' mental health.

RESULTS

Our findings revealed a stable three-factor structure for the DASS-21, characterized by high correlations among depression, anxiety, and stress. The DASS-21 demonstrated strict invariance across genders and weak invariance across levels of education. Network analysis indicated that symptoms of depression, anxiety, and stress form clusters, with some symptoms exhibiting strong correlations with each other.

CONCLUSION

Our study highlights a substantial interrelation among depression, anxiety, and stress, revealing a structurally clustered pattern. Network analysis underscores the interconnectedness and centrality of these symptoms, recommending a shorter version of the DASS, and emphasizing the imperative for targeted interventions aimed at improving the psychological well-being of students.

Comparison of depression, anxiety, perceived stress, and resilience in parents faced with abortion in Iran: a longitudinal study

BACKGROUND

Abortion could impact the mental well-being of parents. Resilience also has a significant effect on the mental health of the family as a factor in coping with abortion. This study aimed to compare depression, anxiety, perceived stress, and resilience in parents after abortion.

METHODS

The present longitudinal study was performed on 200 hospitalized women and their spouses in the post-partum department of Shiraz hospitals in 2023. The instruments used in this study included questionnaires of fertility and demographic characteristics, hospital depression and anxiety (HADS), Connor's resilience, and Cohen's perceived stress. Data analysis was performed using SPSS 25.

RESULTS

The mean age of the fathers was 35.37 ± 4.99 and that of mothers was 31.35 ± 6.23. The scores of parents' anxiety, depression, and perceived stress in the first 24 h after facing abortion were in the highest possible state and decreased in 12 weeks, and their resilience also increased. In all three time periods, the mean scores of the fathers' anxiety, depression, and perceived stress were lower than those of the mothers, but the mean score of resilience was always higher in fathers. Fathers´ age and mothers' age, mothers' age at the time of marriage, fathers' job, number of children, gender of the last child (boy or girl), and unwanted pregnancy were among the predicting variables of anxiety, depression, perceived stress, and resilience of both parents faced with abortion.

CONCLUSION

Although mental disorders in fathers were fewer than mothers compared to post-abortion resilience, identifying and managing these issues promptly is crucial for enhancing post-abortion mental well-being in both parents. How parents navigate the challenges of pregnancy, childbirth, and abortion can significantly impact the couple's health.

A U-shaped relationship between chronic academic stress and the dynamics of reward processing

Despite the potential link between stress-induced reward dysfunctions and the development of mental problems, limited human research has investigated the specific impacts of chronic stress on the dynamics of reward processing. Here we aimed to investigate the relationship between chronic academic stress and the dynamics of reward processing (i.e., reward anticipation and reward consumption) using event-related potential (ERP) technology. Ninety healthy undergraduates who were preparing for the National Postgraduate Entrance Examination (NPEE) participated in the study and completed a two-door reward task, their chronic stress levels were assessed via the Perceived Stress Scale (PSS). The results showed that a lower magnitude of reward elicited more negative amplitudes of cue-N2 during the anticipatory phase, and reward omission elicited more negative amplitudes of FRN compared to reward delivery especially in high reward conditions during the consummatory phase. More importantly, the PSS score exhibited a U-shaped relationship with cue-N2 amplitudes regardless of reward magnitude during the anticipatory phase; and FRN amplitudes toward reward omission in high reward condition during the consummatory phase. These findings suggest that individuals exposed to either low or high levels of chronic stress, as opposed to moderate stress levels, exhibited a heightened reward anticipation, and an augmented violation of expectations or affective response when faced with relatively more negative outcomes.

EEG Evidence of Acute Stress Enhancing Inhibition Control by Increasing Attention

OBJECTIVE

Research about the impact of acute stress on inhibitory control remains a contentious topic, with no consensus reached thus far. This study aims to investigate the effects of acute stress on an individual's inhibitory control abilities and to elucidate the underlying neural mechanisms by analyzing resting state electroencephalogram (EEG) data.

METHODS

We recruited 32 male college students through participant recruitment information to undergo within-subject experiments under stress and non-stress conditions. Physiological indicators (cortisol and heart rate), self-report questionnaires, and behavioral data from the Stroop task were collected before, during, and after the experiment. Additionally, a five-minute eyes closed resting state EEG data collection was conducted during the Stroop task before.

RESULTS

(1) Acute stress led to a reduction in the conflict effect during the participants' Stroop task in individuals. (2) Stress resulted in an increase in the power of the beta in the resting state EEG. (3) Acute stress caused an increase in the duration of class D and an increase in the transition probabilities from classes C and B to class D in the microstates of the resting state EEG. (4) Acute stress leads to an increase in beta power values in individuals' resting state EEGs, which is significantly negatively correlated with the reduction of the conflict effect in the Stroop task under stress.

CONCLUSIONS

Acute stress can enhance individuals' attentional level, thereby promoting inhibitory control performance.

Influence of acute heat shock on antioxidant defense of tropical fish, Psalidodon bifasciatus

Psalidodon bifasciatus is a fish species sensitive to physical and chemical changes in water. It serves as a good bioindicator of temperature variations and is utilized in environmental monitoring studies in Brazilian rivers. The objective of this study was to evaluate antioxidant defense biomarkers in the heart, brain, and muscle of P. bifasciatus exposed to a 10 °C thermal increase. P. bifasciatus were collected and divided into a control group (21 °C) and groups subjected to thermal shock (31 °C) for periods of 2, 6, 12, 24, and 48h. Two-way ANOVA indicated that a 10 °C temperature increase caused oxidative stress in P. bifasciatus. This was evidenced by altered levels of lipid peroxidation (LPO), carbonylated proteins (PCO), and glutathione peroxidase (GPx) in the heart, catalase (CAT) and LPO in the brain, and LPO in the muscle. Principal component analysis (PCA) and integrated biomarker response (IBR) analysis indicated that, compared to the heart and muscle, the brain exhibited a greater activation of the antioxidant response. Sensitivity analysis indicated that the muscle was the most sensitive organ, followed by the brain and heart. Our results indicate that the stress response is tissue-specific through the activation of distinct mechanisms. These responses may be associated with the tissue's function as well as its energy demand. As expected, P. bifasciatus showed changes in response to thermal stress, with the brain showing the greatest alteration in antioxidant defenses and the muscle being the most sensitive tissue.

Acetate enables metabolic fitness and cognitive performance during sleep disruption

Sleep is essential for overall health, and its disruption is linked to increased risks of metabolic, cognitive, and cardiovascular dysfunctions; however, the molecular mechanisms remain poorly understood. This study investigated how sleep disturbances contribute to metabolic imbalance and cognition impairment using a chronic sleep fragmentation (SF) mouse model. SF mice exhibited impaired cognition, glucose metabolism, and insulin sensitivity compared with controls. We identified increased acetate levels in hypothalamic astrocytes as a defensive response in SF mice. Through acetate infusion or astrocyte-specific Acss1 deletion to elevate acetate levels, we observed mitigated metabolic and cognitive impairments in SF mice. Mechanistically, acetate binds and activates pyruvate carboxylase, thereby restoring glycolysis and the tricarboxylic acid cycle. Among individuals most commonly affected by SF, patients with obstructive sleep apnea exhibited elevated acetate levels when coupled with type 2 diabetes. Our study uncovers the protective effect of acetate against sleep-induced metabolic and cognitive impairments.

Targeting fear memories: Examining pharmacological disruption in a generalized fear framework

Labilization-reconsolidation, which relies on retrieval, has been considered an opportunity to attenuate the negative aspects of traumatic memories. A therapeutic strategy based on reconsolidation blockade is deemed more effective than current therapies relying on memory extinction. Nevertheless, extremely stressful memories frequently prove resistant to this process. Here, after inducing robust fear memory in mice through strong fear conditioning, we examined the possibility of rendering it susceptible to pharmacological modulation based on the degree of generalized fear (GF). To achieve this, we established an ordered gradient of GF, determined by the perceptual similarity between the associated context (CA) and non-associated contexts (CB, CC, CD, and CE) to the aversive event. We observed that as the exposure context became less similar to CA, the defensive pattern shifted from passive to active behaviors in both male and female mice. Subsequently, in conditioned animals, we administered propranolol after exposure to the different contexts (CA, CB, CC, CD or CE). In males, propranolol treatment resulted in reduced freezing time and enhanced risk assessment behaviors when administered following exposure to CA or CB, but not after CC, CD, or CE, compared to the control group. In females, a similar change in behavioral pattern was observed with propranolol administered after exposure to CC, but not after the other contexts. These results highlight the possibility of indirectly manipulating a robust contextual fear memory by controlling the level of generalization during recall. Additionally, it was demonstrated that the effect of propranolol on reconsolidation would not lead to a reduction in fear memory per se, but rather to its reorganization resulting in greater behavioral flexibility (from passive to active behaviors). Finally, from a clinical viewpoint, this would be of considerable relevance since following this strategy could make the treatment of psychiatric disorders associated with traumatic memory formation more effective and less stressful.

More efficient adaptation of cardiovascular response to repeated restraint in spontaneously hypertensive rats: the role of autonomic nervous system

We hypothesized that sympathetic hyperactivity and parasympathetic insuficiency in spontaneously hypertensive rats (SHR) underlie their exaggerated cardiovascular response to acute stress and impaired adaptation to repeated restraint stress exposure compared to Wistar-Kyoto rats (WKY). Cardiovascular responses to single (120 min) or repeated (daily 120 min for 1 week) restraint were measured by radiotelemetry and autonomic balance was evaluated by power spectral analysis of systolic blood pressure variability (SBPV) and heart rate variability (HRV). Baroreflex sensitivity (BRS) was measured by the pharmacological Oxford technique. Stress-induced pressor response and vascular sympathetic activity (low-frequency component of SBPV) were enhanced in SHR subjected to single restraint compared to WKY, whereas stress-induced tachycardia was similar in both strains. SHR exhibited attenuated cardiac parasympathetic activity (high-frequency component of HRV) and blunted BRS compared to WKY. Repeated restraint did not affect the stress-induced increase in blood pressure. However, cardiovascular response during the post-stress recovery period of the 7th restraint was reduced in both strains. The repeatedly restrained SHR showed lower basal heart rate during the dark (active) phase and slightly decreased basal blood pressure during the light phase compared to stress-naive SHR. SHR subjected to repeated restraint also exhibited attenuated stress-induced tachycardia, augmented cardiac parasympathetic activity, attenuated vascular sympathetic activity and improved BRS during the last seventh restraint compared to single-stressed SHR. Thus, SHR exhibited enhanced cardiovascular and sympathetic responsiveness to novel stressor exposure (single restraint) compared to WKY. Unexpectedly, the adaptation of cardiovascular and autonomic responses to repeated restraint was more effective in SHR.

Toward stressor-free stress estimation: The integrated information theory explains the information dynamics of stress

Recent neurological studies have revealed several detailed stress mechanisms. However, the latent variables behind stress study still interpret stress responses as difficult. Therefore, we propose a stressor-free method of stress evaluation using Integrated Information Theory (IIT) to address these issues. We conducted experiments inducing acute stress responses against tasks with three levels of difficulty, easy, moderate, and difficult, to verify the IIT in stress study. The moderate condition was related to active coping with stress. By contrast, the easy and difficult conditions are related to passive stress coping. Especially, the easy condition seemed to cause boredom. Our results revealed that the degree of entangled system fluctuation was associated with the subjective ratings for the tasks. Interestingly, our method could also evaluate stress as a state of boredom that had not received much research attention. Our method can be an alternative stress estimation method to overcome the latent variable problem.

Cortisol, Stress, and Disease-Bidirectional Associations; Role for Corticosteroid-Binding Globulin?

Selye described stress as a unified neurohormonal mechanism maintaining homeostasis. Acute stress system activation is adaptive through neurocognitive, catecholaminergic, and immunomodulation mechanisms, followed by a reset via cortisol. Stress system components, the sympathoadrenomedullary system, hypothalamic-pituitary-adrenal axis, and limbic structures are implicated in many chronic diseases by establishing an altered homeostatic state, allostasis. Consequent "primary stress system disorders" were popularly accepted, with phenotypes based on conditions such as Cushing syndrome, pheochromocytoma, and adrenal insufficiency. Cardiometabolic and major depressive disorders are candidates for hypercortisolemic etiology, contrasting the "hypocortisolemic symptom triad" of stress sensitivity, chronic fatigue, and pain. However, acceptance of chronic stress etiology requires cause-and-effect associations, and practical utility such as therapeutics altering stress system function. Inherent predispositions to stress system perturbations may be relevant. Glucocorticoid receptor (GR) variants have been associated with metabolic/neuropsychological states. The SERPINA6 gene encoding corticosteroid-binding globulin (CBG), was the sole genetic factor in a single-nucleotide variation-genome-wide association study linkage study of morning plasma cortisol, a risk factor for cardiovascular disease, with alterations in tissue-specific GR-related gene expression. Studies showed genetically predicted high cortisol concentrations are associated with hypertension and anxiety, and low CBG concentrations/binding affinity, with the hypocortisolemic triad. Acquired CBG deficiency in septic shock results in 3-fold higher mortality when hydrocortisone administration produces equivocal results, consistent with CBG's role in spatiotemporal cortisol delivery. We propose some stress system disorders result from constitutional stress system variants rather than stressors themselves. Altered CBG:cortisol buffering may influence interstitial cortisol ultradian surges leading to pathological tissue effects, an example of stress system variants contributing to stress-related disorders.

Associations between affective temperament, perceived stress, and helping among Ukrainians and Poles in the context of the war in Ukraine

The Russian aggression of Ukraine has put millions of civilians under immense stress and forced many of them to leave their homes for safety and help. Poland became one of the leading destinations for waves of Ukrainians fleeing this war. The level of perceived stress in people who experienced war depends on various factors, including individual psychological variables. The main aim of this study was to analyze perceived stress levels and the predictive role of affective temperaments, as defined by Akiskal, for perceived stress in Ukrainians and Poles during the first year of the Russo-Ukrainian war. Secondly, we studied the relationship between affective temperament, stress, and commitment to help Ukrainian refugees. Self-report data from 410 Ukrainians and 146 Poles were collected. The results of this study shed light on perceived stress in war-affected populations and the role of affective temperaments in predicting its levels. We also demonstrated the links between affective temperament, perceived stress, and involvement in helping Ukrainian refugees. Understanding the mental status of people affected by war and its predictors is crucial to providing appropriate support and assistance to those in need.

Physiological and genomic signatures of war and displacement: A comprehensive literature review and future directions

There are now 108.4 million forcibly displaced people worldwide, many of whom endure adversities that result in trauma, toxic stress, and potentially, altered epigenetic development. This paper provides a comprehensive review of current literature on the biological signatures of war and forced migration among refugee populations. To consolidate evidence and identify key concerns and avenues for future research, we reviewed 36 publications and one article under review, published since 2000, most of which focused on refugees relocated in Europe and the Middle East. This body of work - including cross-sectional, observational, and experimental studies - reveals heterogenous findings regarding human biological responses to war-related adversities and their associations with health outcomes. We conclude with four main observations, regarding why genomic and physiological biomarkers are valuable, what study designs advance understanding of causality and health-promoting interventions, how to prepare for ethical challenges, and why theoretical frameworks and research procedures need more detailed consideration in scientific publications.

Sleep-phasic heart rate variability predicts stress severity: Building a machine learning-based stress prediction model

We propose a novel approach for predicting stress severity by measuring sleep phasic heart rate variability (HRV) using a smart device. This device can potentially be applied for stress self-screening in large populations. Using a Holter electrocardiogram (ECG) and a Huawei smart device, we conducted 24-h dual recordings of 159 medical workers working regular shifts. Based on photoplethysmography (PPG) and accelerometer signals acquired by the Huawei smart device, we sorted episodes of cyclic alternating pattern (CAP; unstable sleep), non-cyclic alternating pattern (NCAP; stable sleep), wakefulness, and rapid eye movement (REM) sleep based on cardiopulmonary coupling (CPC) algorithms. We further calculated the HRV indices during NCAP, CAP and REM sleep episodes using both the Holter ECG and smart-device PPG signals. We later developed a machine learning model to predict stress severity based only on the smart device data obtained from the participants along with a clinical evaluation of emotion and stress conditions. Sleep phasic HRV indices predict individual stress severity with better performance in CAP or REM sleep than in NCAP. Using the smart device data only, the optimal machine learning-based stress prediction model exhibited accuracy of 80.3 %, sensitivity 87.2 %, and 63.9 % for specificity. Sleep phasic heart rate variability can be accurately evaluated using a smart device and subsequently can be used for stress predication.

Corticosterone and glucose are correlated and show similar response patterns to temperature and stress in a free-living bird

Glucocorticoid (GC) hormones have traditionally been interpreted as indicators of stress, but the extent to which they provide information on physiological state remains debated. GCs are metabolic hormones that amongst other functions ensure increasing fuel (i.e. glucose) supply on the face of fluctuating energetic demands, a role often overlooked by ecological studies investigating the consequences of GC variation. Furthermore, because energy budget is limited, in natural contexts where multiple stimuli coexist, the organisms' ability to respond physiologically may be constrained when multiple triggers of metabolic responses overlap in time. Using free-living spotless starling (Sturnus unicolor) chicks, we experimentally tested whether two stimuli of different nature known to trigger a metabolic or GC response, respectively, cause a comparable increase in plasma GCs and glucose. We further tested whether response patterns differed when both stimuli occurred consecutively. We found that both experimental treatments caused increases in GCs and glucose of similar magnitude, suggesting that both variables fluctuate along with variation in energy expenditure, independently of the trigger. Exposure to the two stimuli occurring subsequently did not cause a difference in GC or glucose responses compared with exposure to a single stimulus, suggesting a limited capacity to respond to an additional stimulus during an ongoing acute response. Lastly, we found a positive and significant correlation between plasma GCs and glucose after the experimental treatments. Our results add to the increasing research on the role of energy expenditure on GC variation, by providing experimental evidence on the association between plasma GCs and energy metabolism.