Acute Physiological Stress Response Research Articles

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.

The acute physiological stress responses after total sleep deprivation in health individuals: a systematic review

The acute physiological stress responses after total sleep deprivation in health individuals: a systematic review

Nx4 ameliorated peripheral and central stress-induced changes at resting state - A post hoc analysis of a randomized controlled trial

Psychosocial stress provokes restlessness and perpetuates anxiety states, which may subsequently lead to major psychiatric disorders. Momentary adaptive responses to psychosocial stress can be reflected by electrophysiological (electroencephalogram: EEG) and physiological (heart rate variability: HRV) signals. A recent double-blind, placebo-controlled, crossover trial (NEURIM, NCT02602275) investigated the stress-reducing effects of Neurexan (Nx4) on neurophysiological and physiological changes in response to acute psychosocial stressors. This post hoc analysis aims to explore the stress-reducing effect of Nx4 on peripheral physiological (HRV) and central electrophysiological (EEG) levels at resting state. Thirty-nine healthy male participants received a single dose of Nx4 before exposure to a psychosocial stress paradigm. EEG and photoplethysmogram (PPG) data were acquired before and after psychosocial stress exposure induced by the ScanSTRESS task. Stress responsivity under placebo and Nx4 were assessed by HRV parameters and EEG frequency power. Psychosocial stress induction led to changes (i) in various parameters of heart rate variability, including increased LF/HF ratio, increased Baevsky’s Stress Index, and reduced RMSSD. As well as (ii) to changes in EEG frequency power with increased alpha and decreased theta power, both indicating successful stress induction. Nx4 reduced the stress-induced changes on both peripheral physiological and central electrophysiological levels. In the current study, we showed that the Nx4 reduced the acute peripheral physiological and central electrophysiological stress responses to psychosocial challenges. We suggest Nx4 may be a significant means to buffer the bodily responses of daily life stress exposure.

Ophidiomycosis is associated with alterations in the acute glycemic and glucocorticoid stress response in a free-living snake species

Emerging fungal pathogens are a direct threat to vertebrate biodiversity. Elucidating the mechanisms by which mycoses impact host fitness is an important step towards effective prediction and management of disease outcomes in populations. The vertebrate acute stress response is an adaptive mechanism that allows individuals to meet challenges to homeostasis and survival in dynamic environments. Disease may cause stress, and coping with fungal infections may require shifts in resource allocation that alter the ability of hosts to mount an acute response to other external stressors. We examined the glucocorticoid and glycemic response to acute capture stress in a population of free-living pygmy rattlesnakes, Sistrurus miliarius, afflicted with an emerging mycosis (ophidiomycosis) across seasons. In all combinations of disease status and season, acute capture stress resulted in a significant glucocorticoid and glycemic response. While disease was not associated with elevated baseline or stress-induced corticosterone (CORT), disease was associated with an increased glucocorticoid stress response (post-stress minus baseline) across seasons. Both baseline and stress-induced glucose were lower in snakes with ophidiomycosis compared to uninfected snakes. The relationship between glucose and pre- and post-stress CORT depended on infection status, and positive correlations were only observed in uninfected snakes. The variables which explained CORT and glucose levels were different. The pattern of CORT was highly seasonal (winter high – summer low) and negatively related to body condition. Glucose, on the other hand, did not vary seasonally or with body condition and was strongly related to sex (male high – female low). Our results highlight the fact that circulating CORT and glucose are sensitive to different intrinsic and extrinsic predictor variables and support the hypothesis that disease alters the acute physiological stress response. Whether the effects of ophidiomycosis on the acute stress response result in sublethal effects on fitness should be investigated in future studies.

Variation in salivary cortisol responses in yearling Thoroughbred racehorses during their first year of training.

Thoroughbred horses are bred for competitive racing and undergo intense training regimes. The maintenance of physical soundness and desirable behavioural characteristics are critical to the longevity of a racing career. Horses intended for Flat racing generally enter training as yearlings and undergo introductory training prior to exercise conditioning for racing. This period requires rapid adjustment to a novel environment. As a prey animal, a horse's 'fight-or-flight' response is highly adapted, in which a well-understood component of this response, the hypothalamic-pituitary-axis, is activated in response to a stress stimulus, releasing cortisol. In the Thoroughbred, a significant difference in salivary cortisol concentrations between pre- and post-first time ridden (i.e., first backing) by a jockey have previously been identified. Here, to test the hypothesis that salivary cortisol concentrations may be used to objectively detect individual variations in the acute physiological stress response we investigate individual variation in cortisol response to training milestones. Saliva samples were collected from a cohort of n = 96 yearling Flat racehorses, at the same training yard, across three timepoints at rest: before entering the training yard (n = 66), within three days of entry to the training yard (n = 67) and following 2-3 weeks in the training yard (n = 50). Salivary cortisol concentration was measured using an ELISA. There was no significant difference in cortisol concentration (ANOVA, P > 0.05) across the samples collected at timepoints at rest. Samples were also collected before and 30 minutes after exposure to three novel training events: first time long-reined (n = 6), first time backed by a jockey (n = 34), and first time ridden on the gallops (n = 10). Mean salivary cortisol concentration after all three novel training events was significantly higher than prior to the training event (Paired t-test, P <0.005). The ranges of post-event salivary cortisol concentration across all timepoints suggest individual variation in the measured stress response, reflecting individual differences in stress response to the early training environment. This measure may be used as an objective assessment of the stress response of Thoroughbred racehorses during training.

Physiological reactions to acute stressors and subjective stress during daily life: A systematic review on ecological momentary assessment (EMA) studies.

ObjectiveThis review aims to provide an overview of ecological momentary assessment (EMA) studies analyzing stress reactivity during daily life in terms of direct and moderated influence of acute stress on physiological responses.Materials and methodsA systematic literature search was performed on November 29, 2021 using Web of Science, MEDLINE and PsycINFO to identify prospective EMA studies targeting acute stressors or stress under naturalistic conditions, without restrictions of publication date or population. Study quality was assessed for multiple EMA-specific sources of bias.ResultsOut of 4285 non-duplicate records, 107 publications involving 104 unique studies were included. The majority of studies assessed acute physiological stress responses primarily through salivary cortisol (n = 59) and cardiovascular outcomes (n = 32). Most studies performed at least three measurements per day (n = 59), and had a moderate risk of recall bias (n = 68) and confounding (n = 85). Fifty-four studies reported a compliance of ≥80%. Direct, non-moderated positive associations were observed between acute stress exposure and concurrent cortisol levels (44%, n = 11/25), systolic (44%, 8/18) and diastolic blood pressure (53%, 8/15) and heart rate (53%, 9/17). Several inter- and intra-individual moderators were identified, such as age, gender, health status, chronic stress, work-related resources, physical activity and stress coping indicators.ConclusionsAbout half of the reviewed EMA studies demonstrated direct associations between everyday acute stress exposure and physiological responses, including increased cortisol levels, blood pressure and heart rate. Results further suggested various moderator variables that could help develop tailored prevention strategies and identify groups at higher risk for dysfunctional stress responses.RegistrationPROSPERO—Reg.-No.: PROSPERO 2020 CRD42020163178.

Acute Physiological and Psychological Stress Response in Youth at Clinical High-Risk for Psychosis.

Deficits in stress-response systems are a characteristic of schizophrenia and psychosis spectrum illnesses, and recent evidence suggests that this impairment may be evident in those at clinical high-risk (CHR) for the development of a psychotic disorder. However, there is limited research specifically investigating biological and subjective stress reactivity in CHR individuals. In the present study, 38 CHR individuals and group of 38 control individuals participated in the Trier Social Stress Test (TSST), an experimentally induced psychosocial stressor. Changes in salivary cortisol and alpha amylase, as well as self-reported units of distress (SUDS), were evaluated. Interestingly, the TSST did not induce a change in cortisol levels in either group, though the CHR group did show higher overall cortisol levels throughout the TSST (pre-anticipation period through recovery period). However, indicative of an effective task manipulation, the TSST did illicit an increase in alpha amylase in both groups. CHR participants exhibited higher levels of subjective stress prior to the stressor compared to the control group and CHR SUDs did not significantly increase in response to the stressor. In contrast, the control group showed an increase in SUDS in response to the stressor. Notably, SUDS for the control group post task mirrored the levels CHR youth endorsed prior to the stressor. Taken together, these findings suggest that there may be a functional relationship between persistently elevated cortisol and chronic high levels of subjective distress in CHR individuals.

Evidence of the Associations between Individual and Partner Autonomy Support and Physiological Stress in the Context of Conversations about Weight among Couples Who are Overweight or Obese during a 6-Month Intervention

ABSTRACT The aim of the study was to examine the impact of supportive communication on acute physiological stress responses during weight-related conversations taking place throughout a couples’ weight loss program. Participants were 47 married or cohabitating couples where each partner had a BMI of 25–40 kg/m2. Couples were randomized as a dyad into a traditional weight loss program or a program that also included training in providing support to one’s partner throughout the weight loss process. Structured conversations between partners about weight management were videotaped at baseline and 6 months. Participants provided saliva samples before and after the conversations, which were assayed for cortisol and salivary alpha-amylase (sAA) to determine physiological stress and anxiety responses to conversations about weight. The results indicated that receiving support from one’s partner when discussing weight-related issues was associated with greater physiological stress, as indicated by higher cortisol and sAA levels, whereas providing support to one’s partner was associated with lower cortisol levels and higher sAA levels. The findings suggest that receiving support is not a universally positive experience, especially for populations facing health issues. The mixed findings for support provision align with previous studies identifying a negative association between affectionate communication and cortisol levels, as well as a positive association between sAA and anxiety and emotional arousal. The findings and their implications for understanding the physiological correlates of couples’ conversations about weight are discussed.

Hair cortisol-a stress marker in children and adolescents with chronic tic disorders? A large European cross-sectional study

BackgroundThere is clear evidence that tic disorders (TDs) are associated with psychosocial stress as well as emotional and behavioral problems. Studies have shown that individuals with TDs have higher acute physiological stress responses to external, single stressors (as reflected by saliva cortisol). The aim of the present study was to examine a physiological marker of longer-term stress (as reflected by hair cortisol concentration) in children and adolescents with TDs and unaffected siblings of individuals with TDs.MethodsTwo samples of a European cohort were included in this study. In the COURSE sample, 412 children and adolescents aged 3–16 years with a chronic TD including Tourette syndrome according to DSM IV-TR criteria were included. The ONSET sample included 131 3–10 years old siblings of individuals with TDs, who themselves had no tics. Differences in hair cortisol concentration (HCC) between the two samples were examined. Within the COURSE sample, relations of HCC with tic severity and perceived psychosocial stress as well as potential effects and interaction effects of comorbid emotional and behavioral problems and psychotropic medication on HCC were investigated.ResultsThere were no differences in HCC between the two samples. In participants with TDs, there were no associations between HCC and tic severity or perceived psychosocial stress. No main effects of sex, psychotropic medication status and comorbid emotional and behavioral problems on HCC were found in participants with TDs.ConclusionA link between HCC and TDs is not supported by the present results.

Stress coping strategies and stress reactivity in adolescents with overweight/obesity.

This study explored the associations between the frequency and effectiveness of habitual stress coping strategies on physiological and psychological stress responses to an acute laboratory stressor in adolescents with overweight/obesity (51 adolescents; 47% female; ages 14-19 years). Coping strategies were assessed using the Schoolager's Coping Strategies Inventory. Acute physiological stress responses were measured as salivary cortisol and α-amylase output during the Trier Social Stress Test and during a control condition. Acute psychological stress was measured using a Likert-type scale, and systolic blood pressure (SBP) and heart rate were measured at baseline. Results revealed that higher coping effectiveness was associated with lower log-based α-amylase during the stress (β = -0.025, p = 0.018) and control (β = -0.030, p = 0.005) conditions, but not with cortisol across either condition (all ps > 0.05). SBP moderated the association between coping effectiveness and α-amylase during the stress condition, with higher coping effectiveness associated with lower α-amylase only among individuals with lower SBP (β = 0.002, p = 0.027). Coping frequency was not associated with cortisol responses, neither was habitual stress coping strategies associated with psychological stress (all ps > 0.05). These findings provide preliminary evidence that effective use of stress coping strategies may provide a dampening effect on sympathetic activity in an at-risk adolescent population.

Ex vivo LPS-stimulated cytokine production is associated with cortisol curves in response to acute psychosocial stress

BackgroundEmpirical and theoretical evidence suggest that because of the co-evolution of the endocrine and immune response systems, different types of stressors may lead to similar levels of physiological activation. The present analyses examined associations between two physiological stress responses: the cortisol response to an acute laboratory stressor and ex vivo lipopolysaccharide (LPS) stimulated inflammatory cytokine production. MethodsHealthy middle-aged adults (N = 65) completed testing at two appointments, two weeks apart. Blood was collected at each appointment to measure circulating inflammatory cytokine levels and stimulated inflammatory cytokine production after 4 and 24 hours of incubation with LPS. A cumulative standardized composite measure of inflammation was calculated using the cytokines interleukin-6 (IL-6), interleukin-1β (IL-1β), and interferon-γ (IFN-γ). At visit two, after the blood draw, participants completed the Trier Social Stress Test (TSST); saliva samples were collected before and after to generate cortisol response curves (area under the curve with respect to ground [AUCG] and increase/decrease [AUCI]). ResultsAUCG was significantly associated with stimulated cytokine production at visit 2 after both 4 hours (B = 6.89; p = 0.007) and 24 hours (B = 7.50; p = 0.005) of incubation, controlling for age, sex, and BMI. AUCI was also significantly associated with stimulated cytokine production at visit 2 after 4 hours (B = 6.28; p = 0.004) and 24 hours (B = 6.16; p = 0.007) of incubation, controlling for age, sex, and BMI. Stimulated inflammatory cytokine production was strongly correlated across the two visits (2 weeks apart) after 4 hours of incubation (r = 0.80, p < 0.001) and after 24 hours (r = 0.80, p < 0.001). Within each visit, stimulated cytokine production after 4 hours was significantly correlated with stimulated inflammation at 24 hours (r = 0.93-0.94, p < 0.05) ConclusionsThese results suggest that LPS-stimulated inflammatory cytokine production and the cortisol response to the TSST contain comparable information about acute human physiological stress responses. Moreover, measurement of stimulated cytokines was highly stable across a two-week time period whether measured after 4 or 24 hours of incubation with LPS.

Effect of omega-3 polyunsaturated fatty acid (n-3 PUFA) supplementation to lactating sows on growth and indicators of stress in the postweaned pig1,2.

Dietary omega-3 polyunsaturated fatty acids (n-3 PUFA) are precursors for lipid metabolites that reduce inflammation. Two experiments were conducted to test the hypothesis that enriching the sow diet in n-3 PUFA during late gestation and throughout lactation reduces stress and inflammation and promotes growth in weaned pigs. A protected fish oil product (PFO; Gromega) was used to enrich the diet in n-3 PUFA. In the initial experiment, time-bred gilts were fed a gestation and lactation diet supplemented with 0% (control; n = 5), 0.25% (n = 4), 0.5% (n = 4), or 1% (n = 5) PFO from 101 ± 2 d of gestation to day 16 of lactation. Adding 1% PFO to the diet increased the n-3:n-6 PUFA ratio in colostrum and milk compared with controls (P = 0.05). A subsequent experiment was performed to determine whether supplementing the sow diet with 1% PFO improved growth and reduced circulating markers of acute inflammation and stress in the offspring. Plasma was harvested from piglets (16 per treatment group) on day 0 (d of weaning) and days 1 and 3 postweaning. Pigs from the 1% PFO treatment group weighed more (P = 0.03) on day 3 postweaning and had a greater (P ˂ 0.05) n-3:n-6 PUFA ratio in plasma on each day sampled compared with 0% PFO controls. There was an overall treatment effect on plasma total cortisol (P = 0.03) and haptoglobin (P = 0.04), with lesser concentrations in pigs on the 1% PFO diet. Plasma corticosteroid-binding globulin (CBG) concentrations were not different between treatment groups but were less (P ˂ 0.001) on days 1 and 3 when compared with day 0. The resultant free cortisol index [FCI (cortisol/CBG)] was less (P = 0.02) on days 1 and 3 for pigs from the 1% treatment group compared with the controls. An ex vivo lipopolysaccharide (LPS) challenge of whole blood collected on days 0 and 1 was used to determine whether 1% PFO attenuated release of inflammatory cytokines (IL-1β, IL-6, and TNF-α). Blood from pigs within the 1% PFO treatment group tended (P = 0.098) to have a lesser mean concentration of TNF-α in response to LPS compared with blood from controls. These results suggest that providing a PFO supplement as 1% of the diet to sows beginning in late gestation and during lactation can increase the n-3:n-6 PUFA ratio in their offspring, which may improve growth and reduce the acute physiological stress response in the pigs postweaning.

The acute physiological stress response to driving: A systematic review.

BackgroundThe experience of driving has been suggested to be detrimental to health. One hypothesis is that each exposure elicits an acute stress response, and that repeated exposures may act as a chronic stressor.ObjectiveThe aim of this review is to evaluate and synthesise the evidence on whether driving elicits an acute physiological stress response.MethodsElectronic databases, including CINAHL, PsycINFO and Medline, were searched for original articles written in English from database inception until March 2016. The inclusion criteria of this review included a quantitative examination of an acute physiological stress response to driving, in either on-road or simulated settings, compared to a comparison or control condition. This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting criteria.ResultsA total of 27,295 abstracts were screened and 28 full-text manuscripts retrieved. Of these, seven articles met the inclusion criteria including four simulator studies and three on-road studies. All suggested a significant change in at least one physiological outcome, but the strongest evidence was for increases in urine catecholamine and cortisol after driving for long hours on-road; results on other outcomes are limited by the small number of studies or inconsistent findings.ConclusionsOverall, these studies provided moderate evidence to suggest that driving for long hours elicits a stress response over an extended period of time. There is insufficient evidence that driving for a shorter period of time elicits an acute stress response, especially in real, on-road tasks. However, the limited number of studies, small sample sizes, heterogeneity in study objectives, methodologies and physiological outcomes limit conclusions. Future studies could be improved by recruiting a larger sample, utilizing modern stress markers such as heart rate variability, and primarily focusing on the acute physiological stress response to on-road driving.

Acute Physiological Stress Response of Horses to Different Potential Short-Term Stressors

In order to avoid stress in horses, it has to be known to what extent the animals perceive a challenge as stressful. In this study, salivary cortisol, heart rate, and heart rate variability parameters SDRR (standard deviation of the beat-to-beat interval) and RMSSD (root mean square of successive beat-to-beat differences) were determined in Shetland ponies (six stallions, five mares) in response to a flashlight, exercise without a rider, road transport, and a nontreatment control. Saliva was collected from 1 hour before to 24 hours after the tests, and cardiac activity was recorded from 1 hour before to 2 hours after tests. Salivary cortisol concentration increased in response to transport (P < .001) and remained unchanged in response to exercise, flashlight, and no treatment (P < .001 among tests). Heart rate increased during exercise (150 ± 7 beats/min), followed by transport (99 ± 12 beats/min) and remained unchanged in response to flashlight exposure and no treatment (over time P < .001, among tests P < .001). The SDRR decreased during exercise (P < .01 over time) but not flashlight and control treatment (P < .001 among tests). Changes in RMSSD were similar (P < .001) except for a lack of changes in response to the flashlight. The SDRR differed between mares and stallions (P < .01). In conclusion, horses were not stressed by exposure to the flashlight and exercise without a rider, whereas road transport was perceived as stressful. The response did not differ markedly between stallions and mares.

The effects of autonomy support on salivary alpha-amylase: The role of individual differences

The empirical evidence for the relationship between autonomy-supportive environments and physiological stress is inconsistent. Whereas some studies report a decrease in stress in autonomy-supportive environments, other studies show a negative effect of autonomy on physiological stress. As previous research has not considered individual differences within this relationship, the present research aims to close this empirical gap by proposing that an implicit autonomy disposition, which is defined as a dispositional preference for self-determination, serves as a moderator. In an experiment, we tested whether the autonomy disposition moderates the effect of different teaching styles (controlling, autonomy-supportive, and neutral) on the acute physiological stress response (salivary alpha-amylase) in adolescents (N=69). The study revealed that participants with a high implicit autonomy disposition displayed lower salivary alpha-amylase responses when exposed to autonomy-supportive vignettes compared to when they were exposed to controlling or neutral teaching styles. The opposite pattern was found in students with a low implicit autonomy disposition. The results illustrate that experimentally induced variations in autonomy support lead to different physiological stress responses, depending on individual differences in the implicit autonomy disposition.

The acute physiological stress response to an emergency alarm and mobilization during the day and at night.

The purpose of this study was to investigate the acute physiological stress response to an emergency alarm and mobilization during the day and at night. Sixteen healthy males aged 25 ± 4 years (mean ± SD) spent four consecutive days and nights in a sleep laboratory. This research used a within-participants design with repeated measures for time, alarm condition (alarm or control), and trial (day or night). When an alarm sounded, participants were required to mobilize immediately. Saliva samples for cortisol analysis were collected 0 min, 15 min, 30 min, 45 min, 60 min, 90 min, and 120 min after mobilization, and at corresponding times in control conditions. Heart rate was measured continuously throughout the study. Heart rate was higher in the day (F20,442 = 9.140, P < 0.001) and night (F23,459 = 8.356, P < 0.001) alarm conditions compared to the respective control conditions. There was no difference in saliva cortisol between day alarm and day control conditions. Cortisol was higher (F6,183 = 2.450, P < 0.001) following the night alarm and mobilization compared to the night control condition. The magnitude of difference in cortisol between night control and night alarm conditions was greater (F6,174 = 4.071, P < 0.001) than the magnitude of difference between the day control and day alarm conditions. The augmented heart rate response to the day and night alarms supports previous observations in field settings. Variations in the cortisol responses between conditions across the day and night may relate to differences in participants’ ability to interpret the alarm when sleeping versus when awake.

Sex-Specific Effects of Diets High in Unsaturated Fatty Acids on Spatial Learning and Memory in Guinea Pigs.

Unsaturated fatty acids (UFAs), including omega-3, omega-6 polyunsaturated and omega-9 monounsaturated fatty acids, are essential components and modulators of neuromembranes and may affect various aspects of physiology and cognition. UFAs are suggested to positively affect spatial learning and memory and also to diminish the negative consequences of physiological stress on cognitive abilities. Due to pronounced sex differences in neurophysiological functions, we hypothesize that these UFA-related effects might differ between male and female individuals. We therefore determined the effects of dietary UFAs on cognitive performances in a radial-Y-maze in male and female guinea pigs in relation to saliva cortisol concentrations, a marker for physiological stress. Animals were assigned to four treatment groups and maintained on diets enriched in either chia seeds (omega-3), walnuts (omega-6), or peanuts (omega-9), or a control diet. Female learning abilities throughout a three-day learning phase were positively affected by omega-3 and omega-9, as determined by a decreasing latency to pass the test and the number of conducted errors, while males generally showed distinct learning abilities, irrespective of the diet. A sex difference in learning performances was found in the control group, with males outperforming females, which was not detected in the UFA-supplemented groups. This was paralleled by significantly increased saliva cortisol concentrations in males throughout the cognition test compared to females. Three days after this learning phase, UFA-supplemented males and all females showed unchanged performances, while control males showed an increased latency and therefore an impaired performance. These results were corroborated by pronounced differences in the plasma UFA-status, corresponding to the different dietary treatments. Our findings indicate sex-specific effects of dietary UFAs, apparently enhancing spatial learning abilities only in females and protecting males from long-term memory impairment, while male learning abilities seem to be more strongly affected by an acute physiological stress response to the maze task.

Social evaluative stress in adolescence: Effects of changes in perceived social competence

two different days (5-point daily profiles). Measures of body composition includedweight, height, waist circumference and skinfold thickness. Parents were asked to complete a set of questionnaires on life events, daily hassles and conflicts. Results: Mixed model analyses revealed positive associations between stress exposure and stress responses after controlling for age, gender and parental socioeconomic status. However, stress exposure was not associatedwith body composition nor with daily profiles in these young children. Conclusion: In very young children, stress exposurewas related to a dysregulation of acute physiological stress responses but not chronic stress responses or body composition. The time frame and lack of free access to food to change body composition after stress exposure might have been too short to show an impact within the age group of preschool children.

Effects of work-related sleep restriction on acute physiological and psychological stress responses and their interactions: A review among emergency service personnel.

Emergency work can expose personnel to sleep restriction. Inadequate amounts of sleep can negatively affect physiological and psychological stress responses. This review critiqued the emergency service literature (e.g., firefighting, police/law enforcement, defense forces, ambulance/paramedic personnel) that has investigated the effect of sleep restriction on hormonal, inflammatory and psychological responses. Furthermore, it investigated if a psycho-physiological approach can help contextualize the significance of such responses to assist emergency service agencies monitor the health of their personnel. The available literature suggests that sleep restriction across multiple work days can disrupt cytokine and cortisol levels, deteriorate mood and elicit simultaneous physiological and psychological responses. However, research concerning the interaction between such responses is limited and inconclusive. Therefore, it is unknown if a psycho-physiological relationship exists and as a result, it is currently not feasible for agencies to monitor sleep restriction related stress based on psycho- physiological interactions. Sleep restriction does however, appear to be a major stressor contributing to physiological and psychological responses and thus, warrants further investigation.

Assessing the Effectiveness of Selected Biomarkers in the Acute and Cumulative Physiological Stress Response in Professional Rugby Union through Non-invasive Assessment.

Rugby union is a sport involving high force and frequency impacts making the likelihood of injury a significant risk. The aim of this study was to measure and report the individual and group acute and cumulative physiological stress response during 3 professional rugby games through non-invasive sampling. 24 professional rugby players volunteered for the study. Urine and saliva samples were collected pre and post 3 matches. Myoglobin, salivary immunoglobulin A, cortisol, neopterin and total neopterin (neopterin+7,8-dihydroneopterin) were analysed by high performance liquid chromatography or enzyme linked immunosorbent assay. Significant increases in cortisol, myoglobin, neopterin and total neopterin when urine volume was corrected with specific gravity were observed (p<0.05). Significant decreases in salivary immunoglobulin A concentration were observed for games 1 and 2 while secretion rate decreased after games 2 and 3. Significant decreases were seen with the percent of 7,8-dihydroneopterin being converted to neopterin following games 2 and 3. The intensity of 3 professional rugby games was sufficient to elicit significant changes in the physiological markers selected for our study. Furthermore, results suggest the selected markers not only provide a means for analysing the stress encountered during a single game of rugby but also highlight the unique pattern of response for each individual player.