Physiological Stress Responses Research Articles

Physiological and Psychological Stress Reactivity in Narcolepsy Type 1.

Narcolepsy type 1 (NT1) is a chronic sleep-wake disorder, characterized by a loss of hypocretin production. Unexpectedly, in post-mortem tissue of people with NT1 there is a loss of corticotrophin-releasing hormone (CRH) in the paraventricular nucleus. CRH is known as activator of the hypothalamic-pituitary-adrenal (HPA) axis in response to stress. This activation results in the release of the stress hormones adrenocorticotropic hormone (ACTH) and cortisol. We hypothesize an altered physiological and psychological stress response in NT1. Participants were people with NT1 (n=14) and matched healthy controls (n=12). The Trier Social Stress Test for Groups (TSST-G), a validated socially evaluated stress test in controlled settings, induced acute stress. We measured ACTH and cortisol levels in blood before and at three timepoints after the TSST-G. We also measured subjective stress and heart rate levels. In both groups, acute stress led to increases in ACTH (p=0.006), cortisol (p<0.001), heart rate (p<0.001) and subjective stress (p<0.001). Subjectively, people with NT1 experienced more stress than controls (p<0.001). No differences were found in heart rate, cortisol, and ACTH between people with NT1 and controls at any timepoint. Secondary analyses showed that men with NT1 had lower cortisol levels immediately after stress induction than men in the control group (p=0.002). People with NT1 show an increased subjective stress response, but no changes in their endocrine or cardiovascular stress reactivity. Further research is required to determine the impact of reduced CRH production and gender in NT1.

Infants show negative changes in affect and physiology when re-experiencing a stressor, its context, and a positive event 24-h later.

Exposure to early life stress shapes further development, affects later stress reactivity, and mental health outcomes. Despite the central role of early experiences, there is little understanding of how these rapidly forgotten events gain their influence. An infant's ability to cope with everyday stressors is founded on successful co-regulation through mother-infant interaction. A significant disruption of this interaction through the Face-to-Face Still-Face paradigm elicits a well-documented behavioral and physiological stress response in infants. What has yet to be explored is whether infants show regulatory adaptions when encountering the situation over again. To fill this gap, 80 mother-infant dyads were observed in the lab on two consecutive days. Infants in the experimental condition (n=40) were exposed to a double Still-Face paradigm on day one. Infants in the control group (n=40) completed time-matched episodes of typical play during their first visit. Mother-infant dyads from both groups returned to the lab 24h later and participated in the double Still-Face paradigm. Changes in behavior (positive and negative affect), physiology (heart rate), and salivary cortisol, compared to day one and between groups, were evaluated and used to infer adaption to the previous experienced laboratory visit. Infants in the experimental condition showed a significant decrease in positive affect (p=0.016) and an increase in heart rate (p<0.001) on day two, compared to controls, even during baseline measures and a neutral first play episode. Infants in the control condition showed a significant decrease in affect (p=0.05) and non-significant increase in heart rate on day two when first encountering the Still-Face paradigm. Infants in the experimental condition showed significant higher heart rate on day two compared to the control group (p=0.046). Infants in the experimental condition also exhibited a marginally significant increase in salivary cortisol on day two, compared to day one (p=0.054). The change in infant heart rate was independent of maternal heart rate which did not differ between day one and day two, or between groups. Findings suggest that a previous stressful experience may elicit a behavioral and physiological adaption in infants 24h later. Our results suggest that even a short, acute stressful event can elicit a lasting stress response in infants 24h later. The effect we observed was specific to the context of the stressful event, not just the stressor. More precisely, the effect "spilled over" from the stressful experience on day one into the baseline measure of day two, usually a neutral experience. The results could have implications for further research on how stressful experiences may shape the stress response.

Genome-Wide Characterization of Class III Peroxidases and Their Expression Profile During Mycorrhizal Symbiosis and Phosphorus Deprivation in Lettuce (Lactuca sativa L.)

Lettuce cultivation requires high fertilizer inputs, which impact the environment and costs. Arbuscular mycorrhizal symbiosis (AMS) can reduce fertilizer use, enhance plant nutrition (especially phosphorus), and promote healthier plants. Class III peroxidases (PRXs) play crucial roles in various physiological processes and stress responses. However, their role in AMS and phosphorous (P) deficiency is still unclear. Our study identified 91 PRX genes in the lettuce genome (LsPRXs) and clustered them into eight subfamilies based on phylogenetic relationships. Evolutionary analysis indicated that tandem duplication was the main driver for LsPRX gene family expansion. Synteny analysis showed orthologous relationships of the PRX gene family between lettuce and potato, Arabidopsis, and maize, identifying 39, 28, and 3 shared PRXs, respectively. Transcriptomic data revealed that most LsPRX genes were more expressed in roots than in leaves and differentially expressed LsPRXs were found in response to AMS and P supply. Notably, 15% of LsPRX genes were differentially expressed in roots during mycorrhization. Gene expression network analysis highly correlated five LsPRXs (LsPRX17, LsPRX23, LsPRX24, LsPRX64, and LsPRX79) with genes involved in cell wall remodeling and reorganization during mycorrhization. Our results provide insights into the evolutionary history and functional roles of PRX genes in lettuce and identify candidate gene targets that may enhance the bio-stimulant effects of AMS and help to cope with P deficiency.

Comparison of forced and voluntary exercise types on male rat brain monoamine levels, anxiety-like behaviour, and physiological indexes under light and dark phases

PurposePhysical exercise improves physical and mental health; however, the differences between voluntary and forced exercise protocols are unclear. In addition, knowledge regarding the consequences of differences in testing timing, such as light and dark phases, in response to exercise type is limited. We investigated the effects of chronic forced and voluntary wheel running on the changes in brain monoamine levels (5-HT: serotonin, DA: dopamine, NA: noradrenaline), anxiety-like behaviours, and physiological stress responses in the light and dark phases. MethodsAdult male Wistar rats were equally and randomly assigned to four groups: sedentary control, voluntary exercise (free running on a wheel, V-EX), voluntary limited exercise (wheel available only 1h/day, VL-EX), and forced exercise (running on a motorised wheel, F-EX). Each group was further divided into dark- or light-experimental condition groups. After 4 weeks, the rats underwent an open-field test. The monoamines and their metabolite levels were measured in the major neural cell bodies and the projection areas related to behaviour, cognition, anxiety, and stress in the brain. ResultsAdrenal hypertrophy and elevated body temperature, except during the exercise period, were observed in the F-EX rats that exhibited anxiety-like behaviour. The levels of monoamines and their metabolites, particularly the 5-HTergic and DAergic systems, in specific areas, were significantly altered in the rats in the V-EX group compared to those in the VL-EX and other groups. These differences were observed only in the dark phase. ConclusionThe results suggest that V-EX mainly stimulates the 5-HTergic and DAergic systems, while F-EX induces physiological stress and increases anxiety-like behaviour during the dark phase. This study highlights the importance of accounting for exercise types and light/dark phases in behavioural neuroscience experiments.

Voluntary food restriction does not affect circulating corticosterone in obesity-prone or -resistant male and female rats

Food restriction in rodents can increase circulating corticosterone, which reflects activation of physiological stress responses. These responses affect a myriad of behaviors and physiological processes and can increase the risk of obesity. Most of these studies have used experimenter-imposed restriction. However, rats will voluntarily restrict their food intake if they are returned to chow after a period of access to sugary, fatty “junk food” (JF) diet. Here we examine the effects of voluntary food restriction in obesity-prone and -resistant rats on circulating corticosterone concentrations and determine whether corticosterone release in response to acute stress differs in groups with a history of JF consumption.

No Effects of Omega-3 Supplementation on Kynurenine Pathway, Inflammation, Depressive Symptoms, and Stress Response in Males: A Placebo-Controlled Trial.

Background: Increased inflammation and heightened physiological stress reactivity have been associated with pathophysiology of depressive symptoms. The underlying biological mechanisms by which inflammation and stress may influence neurogenesis are changes in the kynurenine (KYN) pathway, which is activated under stress. Supplementation with n-3 polyunsaturated fatty acids (n-3 PUFAs) has anti-inflammatory properties and can increase stress resilience. Whether n-3 PUFAs alter KYN stress response is unknown. Objectives: This placebo-controlled study investigated the effect of n-3 PUFAs on KYN metabolism, inflammation, depressive symptoms, and mood. Moreover, stress-induced changes following a laboratory stressor have been assessed. Methods: In this placebo-controlled study, 47 healthy male adults received either 4 g n-3 PUFAs per day (Omega-3 group) or a placebo (Placebo group) for 12 weeks. Results: A significant group-by-time interaction was found for the inflammatory markers gp130 (F = 7.07, p = 0.011), IL-6R alpha (F = 10.33, p = 0.003), and TNF_RI (F= 10.92, p = 0.002). No significant group-by-time interactions were found for KYN metabolites, depressive symptoms, and mood (except for Hedonic tone (F = 6.50, p = 0.014)), nor for stress-induced changes in KYN metabolites and mood following a laboratory stressor. Conclusions: Overall, increased n-3 PUFA levels in healthy men ameliorate inflammatory markers but do not ameliorate KYN metabolism, depressive symptoms, mood, or KYN metabolism and mood following a stress induction. This study was registered at ClinicalTrials.gov with the identifier NCT05520437 (30/08/2022 first trial registration).

Comparison of Physiological Stress Indices in Anesthetized and Manually Restrained Leopard Sharks, Triakis semifasciata

Background: Leopard sharks (Triakis semifasciata) are abundant, coastal, eastern Pacific, mesopredatory sharks and are frequently managed in aquariums and zoos. Medical examinations are a routine part of good husbandry practices, but the handling protocols vary greatly between facilities. In this study, we compared the physiological stress responses of T. semifasciata associated with manual restraint and sedated handling under parallel holding and handling procedures in a 10 min interval. Methods: Blood was collected and analyzed for the hematocrit (Hct), lactate, glucose, beta-hydroxybutyrate (β-HB), pH, blood gasses, 1α-hydroxycorticosterone (1α-OHB), and corticosterone (B). Results: Overall, a minimal physiological stress response was observed in both groups. However, statistically significant increases in the PCO2, β-HB and lactate occurred, while the pHTC, SO2, and BE decreased over time in the manual-restraint group. In the sedated group, the B, PCO2, and lactate increased while the pHTC, SO2, and base excess (BE) decreased over time. When comparing treatments, the sedated group had a higher B and PCO2 TC and a lower pHTC, BE, and SO2 than the manual-restraint group at the second time point. Conclusions: This study indicates that manual restraint is comparable to the described sedation in T. semifasciata for minimally invasive procedures. The overall results show that this species had low physiological stress responses to both methods.

Emphasizing the Communal Demands of a Leader Role Makes Job Interviews Less Stressful for Women But Not More Successful

The cultural construal of leadership as masculine impedes women’s attainment of leader roles. This research examined whether adding feminine demands to a leader role relieved the greater stress experienced by women than men in a job interview for a leadership position and considered the processes that mediated women’s less favourable interview outcomes. In a hiring simulation, management students (N = 209; 112 women, 97 men) interviewed for a leader role framed by either stereotypically feminine or masculine role requirements. As shown by the stress biomarker salivary cortisol, the feminine role framing alleviated women’s, but not men’s, physiological stress response during the interview. However, under both masculine and feminine role framing, women, compared with men, reported lesser fit, expected poorer interview performance, appraised greater threat relative to challenge, and evaluated their performance less favourably, as did external raters. An additional vignette study (N = 305; 189 women, 111 men, 5 diverse) found that the feminine role framing increased the leader role’s communal demands but still conveyed strong agentic demands not different from those of the masculine role. In conclusion, although a feminine role framing alleviated women’s physiological stress response, it did not change their less favourable outcomes, as indicated by participants’ self-reports and others’ reports.

Timing matters in stress appraisal: The relationship between retrospective appraisal and stress responses

BackgroundAlthough psychosocial stressors are known to impact task performance and trigger neuroendocrine responses, the dynamic nature of the stress appraisal process is often neglected in research. GoalThis study aims to explore whether self-reported appraisals at various time points can accurately represent an individual’s behavioral and physiological stress responses. MethodsA total of 137 participants were recruited to induce individual stress states using the Trier Social Stress Test (TSST). Self-reported appraisals were measured both before (anticipatory appraisal) and after the stressor (retrospective appraisal) to capture the dynamic process. Concurrently, participants' cortisol responses and task performances were documented. ResultsFindings indicate that anticipatory appraisal does not significantly reflect task performance. In contrast, retrospective appraisal is strongly associated with the performance of corresponding tasks. Regarding cortisol levels, significantly negative results of multiple regression analysis revealed that the retrospective appraisal of the speech task is the sole variable to represent the cortisol response under stress. DiscussionThe results highlight that retrospective appraisals could represent individuals’ behavioral and physiological responses to stressors more accurately than anticipatory appraisals. These findings provide empirical evidence for choosing the appropriate timing to acquire accurate self-reported appraisals and also help to build a mapping relationship between self-reported, behavioral, and physiological data.

Parental Depression Symptoms, Skin Conductance Level Reactivity and Parenting: Associations with Youth Psychopathology.

Parental depression symptoms are a prevalent risk factor for internalizing and externalizing problems in youth, with parenting and parents' physiological stress reactivity representing potential contributing factors in the intergenerational transmission of psychopathology symptoms. In a sample of adolescents (N = 97) and their parents, the current study examined parental depression symptoms, an observational measure of parenting, and parents' physiological reactivity during a dyadic conflict discussion task in association with adolescents' internalizing and externalizing psychopathology. Parental depression symptoms and harsh/insensitive parenting showed positive associations with youth psychopathology symptoms. Further, parental depression symptoms were associated with greater externalizing symptoms in youth, specifically for parents with higher physiological reactivity during the conflict task. The present study highlights risks associated with parental depression and harsh/insensitive parenting, and provides evidence for parental physiological reactivity as a moderator of the association between parent and youth psychopathology. Clinical implications, limitations, and directions for future research are discussed.

Relationship between Sleep Quality and Vertigo Incidence in College Students

One-third of adults are affected by poor sleep quality. Sleep problems are not only experienced by adults. Knowing the relationship between sleep quality and the incidence of vertigo is very important and urgent because of its very broad impact on health, understanding pathophysiology, clinical development, improving quality of life, as well as education and awareness in the community, especially students. In Indonesia, the prevalence of sleep disorders in adolescents is 62.9%. This study aims to determine the relationship between sleep quality and the incidence of vertigo in students. Literature review using Google Scholar, National Center for Biotechnology Information (NCBI) &amp; Research Science found 9 journals based on inclusion &amp; exclusion criteria. The results of the research is the relationship between sleep quality and vertigo involves a complex interaction between physiological and psychological factors. Physiological effects include disorientation and instability, motor coordination, and physiological stress responses such as cortisol. The psychological effects that can occur are anxiety, depression, decreased concentration, decreased cognitive function, and increased psychological discomfort. Lack of sleep in students makes vertigo symptoms worse. Lack of sleep will make vertigo symptoms worse. It is best to arrange the right sleeping position so that symptoms of vertigo do not occur, because vertigo can occur even in people who have never experienced it. The conclusion is there is a relationship between sleep quality and the incidence of vertigo in students.

Stress responses of infants and mothers to a still-face paradigm after traumatic childbirth

IntroductionOne-third of women experience childbirth as traumatic and some develop symptoms of childbirth-related posttraumatic stress symptoms (CB-PTSS). Whether CB-PTSS negatively impact on physiological and psychological stress responses in mothers and their offspring and whether they are associated with mother-infant synchrony is not clear. This study aimed to investigate stress responses of (1) mothers with CB-PTSS, (2) of their infant, and (3) the physiological mother-child-synchrony at six months postpartum. MethodPsychophysiological (cortisol and vagal tone) and psychological stress responses of mothers and infant’s (n=31 dyads) from the Swiss TrAumatic biRth Trial (NCT03576586) were assessed during a face-to-face still-face paradigm (FFSF-R). ResultsThere was a significant time effect in maternal stress responses for salivary cortisol, vagal tone, and for maternal subjective stress. As expected, mothers’ subjective stress increased during the stress task and mothers vagal tone changed during the first stressful period but not during the second, whereas cortisol unexpectedly decreased over the FFSF-R. Infant negative mood increased over the experiment, but there were no physiological changes. However, a significant interaction effect for mother-infant synchrony during the second reunion period of the FFSF-R was found. ConclusionAlthough mothers and their infants were subjectively stressed, they showed only limited physiological stress responses.

The Short Stress State Questionnaire in German (SSSQ-G)

Abstract: Background: Although the physiological stress response is well established, self-reported stress has received less attention. Some validated measures assess task-related stress via self-report in English. However, no such measure exists in Germany. Aims: To address this research gap, we translated and validated the Short Stress State Questionnaire in German (SSSQ-G). It assesses stress-related affective states (e.g., anger) and appraisals (e.g., feelings of control). We expected to replicate the factor structure of the English SSSQ in the SSSQ-G. Methods: We included the SSSQ-G in five studies that induced stress either via the gold standard task for acute stress induction – the Trier Social Stress Test (TSST) – or via a novel virtual reality (VR) task. The sample consisted of 213 participants (112 women; age: 23.36 ± 3.62 years). Results: The SSSQ-G demonstrated sensitivity to stress-induced changes ( ps &lt; .01), particularly in response to the TSST compared to the VR stress induction ( p &lt; .001 for total scale comparison between stressors). In TSST participants, the magnitudes of stress-induced changes on the SSSQ-G were larger than those on the Positive and Negative Affect Schedule (PANAS), p = .008, indicating strong construct validity. Although the SSSQ-G total score was highly reliable (α = .85, Ω = .86), factor analyses revealed a six-factor solution, with the factors representing Distress, Worry, Confidence, Negative affect, Motivation, and Self-evaluation. Limitations: The SSSQ-G appears more sensitive to state changes induced by moderate-to-severe stress tasks. Conclusion: The SSSQ-G is a reliable and valid instrument for assessing states of subjective stress.

Evaluating the impact of artificial intelligence-based assessment of body composition on primary artificial urinary sphincter placement outcomes.

Sarcopenia, characterized by low muscle mass, and aberrant adiposity changes, including visceral fat accumulation, has been associated with impaired physiologic stress response and wound healing. Artificial urinary sphincter (AUS) placement is the preferred surgical treatment for men with severe post-prostatectomy incontinence. Given the higher rates of maladaptive body composition changes in this older, high comorbidity population, this study explores their impact on AUS outcomes. A retrospective analysis was performed including men who underwent primary AUS placement at the Mayo Clinic from 1999 to 2023 for post-prostatectomy incontinence and had cross sectional imaging available within 12 months prior to AUS implant. Sarcopenia and body composition were assessed from the available computed tomography (CT) scan using an algorithm that measures the area of different tissues at the L3 abdominal cross-section. The study investigated the association between sarcopenia [defined as skeletal muscle index (SMI) <52.4 cm2/m2] and adiposity (defined by total visceral and subcutaneous fat area) with all-cause reoperation, including specific etiologies of device infection/erosion, urethral atrophy, and device malfunction, using Cox proportional hazards models. There were 111 patients who had available imaging within the study timeframe, 61 (55%) of whom were classified as sarcopenic. Follow-up did not differ significantly between the two groups [2.11 (0.53-4.78) vs. 2.52 (0.36-5.80) years, P=0.52]. Sarcopenic patients had a lower body mass index (BMI) (29.1 vs. 32.7 kg/m2; P<0.001). No significant difference in overall device survival was observed between sarcopenic and non-sarcopenic patients (P=0.94) on Cox survival analysis. Sarcopenic patients had higher device infection rates, accounting for 16.7% (3/18) of device failures in the sarcopenic cohort compared to none in the non-sarcopenic cohort. Sarcopenia was prevalent among AUS patients but did not significantly impact overall device survival. These findings suggest that AUS placement may be feasible to perform in well-selected sarcopenic patients.

Psychobiological Stress Response Profiles in Current and Remitted Depression: A Person-Centered, Multisystem Approach

BackgroundA dysregulated stress response, including exaggerated affective reactivity and abnormal hypothalamic–pituitary–adrenal (HPA) axis responsivity, has been implicated in the etiology, maintenance and relapse of major depressive disorder (MDD). Among adolescents, discordant affective and physiological stress response profiles have been linked to negative affective outcomes and increased risk for psychopathology. Whether these findings extend to adults with varying degree of MDD risk is unclear, as are possible links to various risk factors. MethodsWe used a person-centered, multisystem approach in a sample of 119 unmedicated adults with current or remitted MDD, as well as individuals without past MDD to evaluate psychobiological stress response profiles. Multi-trajectory modeling was applied to positive affect, negative affect, and salivary cortisol (CORT) levels in response to the Maastricht Acute Stress Test. ResultsAnalyses identified four within-person profiles, one typical, Normative (n=32, 26.9%); and three atypical: CORT Hyperreactivity Affective Stability (n=17, 14.3%), CORT Hyporeactivity Affective Reactivity #1 (n=45, 37.8%), and CORT Hyporeactivity Affective Reactivity #2 (n=25, 21.0%). Validating the assumption of a Normative profile and increased risk for psychopathology in non-normative stress-response profiles, coherent associations emerged between stress response profiles and clinical status, depression severity, anhedonia, perceived stress, childhood adversity and reports of well-being, suggesting increased risk for psychopathology for individuals with a hyperreactive or discordant hyporeactive stress response profiles. ConclusionThis work advances our understanding of stress response mechanisms in MDD and underscores the potential of targeted interventions to enhance resilience and reduce psychopathology based on individual stress response profiles.

Seasonal and Sexual Variations in Corticosterone and Total Triiodothyronine: A Pilot Study in Mediterranean Tortoises (Testudo hermanni).

The Mediterranean tortoise Testudo hermanni inhabits different regions bordering the northwestern Mediterranean. This species is vulnerable, protected by legislation, and involved in various breeding and reintroduction programs. Wild populations face numerous environmental and anthropogenic stressors that can potentially interfere with their conservation. While seasonal changes in stress-response biomarkers, such as glucocorticoids and thyroid hormones, have been widely studised in mammals and birds, there is a paucity of research in reptile species. Therefore, the present study aimed to evaluate the seasonal fluctuations in corticosterone and total triiodothyronine levels in adult and juvenile Hermann's tortoises (Testudo hermanni) as a measure of the physiological stress response. Blood samples were collected seasonally (winter, spring, summer, and autumn) and posteriorly analyzed by using a specific and validated enzyme immunoassay for both hormones, respectively. The results showed that corticosterone levels varied seasonally and differed between sexes, whereas total triiodothyronine levels changed seasonally but did not differ between sexes. Notably, juveniles exhibited no seasonal changes in either corticosterone or total triiodothyronine levels. Additionally, no correlation between blood extraction duration and hormonal concentrations was observed. This study is pioneering in its comprehensive evaluation of corticosterone and total triiodothyronine changes across all four seasons, including winter, and its focus on juvenile Hermann's tortoises.

Examining the applicability of virtual battle space for stress management training in military personnel-A validation study.

Military personnel are often exposed to high levels of both physical and psychological challenges in their work environment and therefore it is important to be trained on how to handle stressful situations. The primary aim of this study was to examine whether military-specific virtual battle space (VBS) scenarios could elicit a physiological and subjective stress response in healthy military personnel, as compared to that of a virtual reality height exposure (VR-HE) stress task that has shown to reliably increase stress levels. Twenty participants engaged in two VBS scenarios and the VR-HE during separate sessions, while measurements of heart rate (HR), heart rate variability (HRV), respiration rate, and subjective stress levels were collected. Contrary to our initial expectations, analysis revealed that neither of the VBS scenarios induced a significant stress response, as indicated by stable HR, HRV, and low subjective stress levels. However, the VR-HE task did elicit a significant physiological stress response, evidenced by increased HR and HRV changes, aligning with previous research findings. Moreover, no discernible alterations were detected in cognitive performance subsequent to these stressors. These results suggest that the current VBS scenarios, despite their potential, may not be effective for stress-related training activities within military settings. The absence of a significant stress response in the VBS conditions points to the need for more immersive and engaging scenarios. By integrating interactive and demanding elements, as well as physical feedback systems and real-time communication, VBS training might better mimic real-world stressors and improve stress resilience in military personnel. The findings of this study have broader implications for stress research and training, suggesting the need for scenario design improvements in virtual training environments to effectively induce stress and improve stress management across various high-stress professions.

Validation of the Virtual Reality Stroop Room: Effects of inhibiting interfering information under time-pressure and task-switching demands

The physiological stress response affects executive functions, such as inhibition, as assessed by the Stroop Color and Word Test. In this study, we investigated the effects of the Virtual Reality Stroop Room (VRSR), a research paradigm assessing these cognitive top-down processes while inducing mild acute stress, on self-reported stress states, heart rate, salivary alpha-amylase, and cortisol. Our sample consisted of 89 participants (52 women; Age: 23.60 ± 3.88 years) and was evenly allocated to the three conditions of the VRSR (regular, time pressure, and rotation). The Stroop Effect, reflected in prolonged processing times and increased errors in the incongruent phase, was observed. Participants reported heightened Distress and Engagement post-experiment, alongside lower Worry, assessed via the Short Stress State Questionnaire. Scores from the Positive and Negative Affect Schedule indicated elevated positive affect and decreased negative affect post-study. With regard to biosignals we found that heart rate was higher in the incongruent phase, compared to the congruent phase and a significant time × condition interaction was observed. Salivary alpha-amylase exhibited a significant time effect. Results for cortisol do not support a uniform response of the hypothalamus-pituitary-adrenal (HPA) axis. In conclusion, the VRSR appears to be a valid measure for executive functions while activating the sympathetic nervous system, but not the HPA axis. Its current implementation induces mild physiological and psychological stress responses, with fewer adverse reactions compared to the Trier Social Stress Test. Future studies should leverage the adaptability of virtual reality applications to refine this research paradigm.

Exogenous supply of potassium decreases the phytotoxicity of heat and salt stress in quinoa by ameliorating physiological and oxidative stress responses

Exogenous supply of potassium decreases the phytotoxicity of heat and salt stress in quinoa by ameliorating physiological and oxidative stress responses

Electrophysiological detection of exam stress inhealth schools' students.

Anxiety is a common issue among university students, many of them experience anxiety, depression, and stress during their school life. This study aimed to compare the acute physiological stress responses of students divided into two groups according to their perceived anxiety levels (positive test anxiety, PTA+, and negative test anxiety, PTA-). Heart rate variability (HRV) and electrodermal activity (EDA) were used to assess stress.Thirty-one healthy volunteers participated in the study. Participants completed anxiety assessments, including the Westside Test Anxiety Scale (WTAS), the State-Trait Anxiety Inventory (STAI), and the Test State Anxiety Inventory (TSAI). Based on their scores, participants were categorized into PTA+ and PTA- groups. All participants underwent 24-h continuous recordings of pulse and electrodermal activity (EDA) on two separate occasions: one day prior to a written exam and during a designated exam-free day serving as a baseline control.We compared the HRV and EDA data obtained on a regular day and on an exam day between the two groups. Results showed that the PTA+ group had significantly higher heart rate, stress index, low frequency, and short-term detrended fluctuation analysis (DFAα1) on the exam day. The tonic EDA component was also higher in the PTA+ group. Stress-related HRV and EDA parameters were negatively correlated with exam scores.In conclusion, the study found that physiological stress indicators obtained from HRV and EDA are associated with perceived exam anxiety in students.