Stressful Episodes Research Articles

Frequency of appearance of transverse (Harris) lines reflects living conditions of the Pleistocene bear-Ursus ingressus-(Sudety Mts., Poland).

Transverse lines, called Harris Lines (HL), osteological markers of recovery from growth arrest episodes, are visible in radiograms of recent and Pleistocene fossil bones. Since on the one hand they mark stressful episodes in life, and on the other are mainly used to trace health fluctuations in prehistoric human communities, I used a cave bear population to check if the processes that could affect the specie’ condition were in any way reflected in the bone structure. 392 bear bones from Bear Cave in Kletno (collection: Department of Palaeozoology, University of Wrocław), dated as 32 100 ±1300 to >49 000 years BP, were radiologically examined. The bones were found in a non-anatomical position; morphological analysis indicated that they belonged to different individuals. HL shadows were observed on 9 tibiae and 3 radii: 8.8% out of the 59 tibiae and 77 radii and 3.1% of all the bones. At least 3 transverse lines were recognised in those cases; the specimens were histologically examined. The bear individuals in question experienced regular malnutrition periods during their ontogeny. Starvation resulting in growth inhibition involved young individuals, aged 1 to 4 years. Juveniles aged 6 months, i.e. before weaning, or younger, showed no signs of nutritional stress. Starvation periods associated with seasonal food deficit were not long or common and had no significant effect on the development and welfare of the species. This is the first description of the occurrence of transverse lines in the Pleistocene bear.

Exploring Suitable Emotion-Focused Strategies in Helping Students to Regulate Their Emotional State in a Tutoring System: Malaysian Case Study

Introduction. This study explored the suitable emotion-focused strategies in helping students to regulate their emotional state in a self-regulated tutoring system.Method. A questionnaire which consists of 25 different regulation strategies adapted from Ways of Coping questionnaire (WCQ) was used to determine the strategies deployed by the students to regulate their emotional state during stressful learning episodes. The questionnaire was distributed in person to 227 unpaid students (132 males and 95 females) from the College of Information Technology, Universiti Tenaga Nasional in Malaysia. This questionnaire was distributed at the beginning of their class and no time limit was imposed. Students were asked to hand in the survey as soon as they had completed the questionnaire.Results. Findings from this study indicated that students used both emotion-focused and problem-focused strategies as their self-regulation strategies in dealing with stressful learning episodes. In addition, the selection of the self-regulation strategies was influenced by students’ gender and religion.Discussion and Conclusion. Moreover, two emotion-focused strategies were identified to potentially be integrated into a self-regulated tutoring system framework: relaxation exercise and supplication strategies.

Neurobehavioural effects of Lactobacillus rhamnosus GG alone and in combination with prebiotics polydextrose and galactooligosaccharide in male rats exposed to early-life stress

Early life is a period of significant brain development when the brain is at its most plastic and vulnerable. Stressful episodes during this window of development have long-lasting effects on the central nervous system. Rodent maternal separation (MS) is a reliable model of early-life stress and induces alterations in both physiology and behaviour. Intriguingly, the gut microbiota of MS offspring differ from that of non-separated offspring, suggesting a mechanistic role for the microbiota–gut–brain axis. Hence, we tested whether dietary factors known to affect the gut microbiota alter the neurobehavioural effects of MS. The impact of consuming diet containing prebiotics polydextrose (PDX) and galactooligosaccharide (GOS) alone or in combination with live bacteria Lactobacillus rhamnosus GG (LGG) from weaning onwards in rats subjected to early-life MS was assessed. Adult offspring were assessed for anxiety-like behaviour in the open field test, spatial memory using the Morris water maze, and reactivity to restraint stress. Brains were examined via PCR for changes in mRNA gene expression. Here, we demonstrate that diets containing a combination of PDX/GOS and LGG attenuates the effects of early-life MS on anxiety-like behaviour and hippocampal-dependent learning with changes to hippocampal mRNA expression of genes related to stress circuitry, anxiety and learning.

Validation of the German version of the Ford Insomnia Response to Stress Test.

The purpose of this study was to assess the psychometric properties of a German version of the Ford Insomnia Response to Stress Test with groups with and without sleep problems. Three studies were analysed. Data set 1 was based on an initial screening for a sleep training program (n=393), data set 2 was based on a study to test the test-retest reliability of the Ford Insomnia Response to Stress Test (n=284) and data set 3 was based on a study to examine the influence of competitive sport on sleep (n=37). Data sets 1 and 2 were used to test internal consistency, factor structure, convergent validity, discriminant validity and test-retest reliability of the Ford Insomnia Response to Stress Test. Content validity was tested using data set 3. Cronbach's alpha of the Ford Insomnia Response to Stress Test was good (α=0.80) and test-retest reliability was satisfactory (r=0.72). Overall, the one-factor model showed the best fit. Furthermore, significant positive correlations between the Ford Insomnia Response to Stress Test and impaired sleep quality, depression and stress reactivity were in line with the expectations regarding the convergent validity. Subjects with sleep problems had significantly higher scores in the Ford Insomnia Response to Stress Test than subjects without sleep problems (P<0.01). Competitive athletes with higher scores in the Ford Insomnia Response to Stress Test had significantly lower sleep quality (P=0.01), demonstrating that vulnerability for stress-induced sleep disturbances accompanies poorer sleep quality in stressful episodes. The findings show that the German version of the Ford Insomnia Response to Stress Test is a reliable and valid questionnaire to assess the vulnerability to stress-induced sleep disturbances.

Measuring the Severity of Stress-Test Scenarios

This note presents a simple methodology for measuring the severity of stress-test scenarios, which relies on a comparison of scenario developments with historically stressful episodes--specifically, recessions and house-price retrenchments.

Prenatal stress exposure as a risk factor for anorexia nervosa: A controlled study

IntroductionPrenatal risk factors, such as gestational complications and exposure to stress during pregnancy, may have a role in the development of many psychiatric disorders including eating disorders.AimTo investigate the impact of prenatal stress exposure on the development and clinical features of anorexia nervosa.MethodsOne hundred and nine patients with a lifetime diagnosis of anorexia nervosa and 118 healthy controls underwent a clinical assessment, which included interviews, questionnaires and a neuropsychological battery. The mothers of the patients and controls underwent a specific interview focused on stressful life events, which occurred during pregnancy. Obstetric and neonatal records were consulted.ResultsThe mothers of patients experienced more severe stressful episodes during pregnancy than the mothers of controls and the perceived distress showed significant positive correlation with both total number of obstetrical complications and placental weight. In patients, the severity of stressful events was strongly associated to cognitive rigidity and perseverance.ConclusionsPrenatal stress exposure might be a risk factor for the development of anorexia nervosa and it is associated with cognitive traits of rigidity and perseverance.Disclosure of interestThe authors have not supplied their declaration of competing interest.

Memory for objects and startle responsivity in the immediate aftermath of exposure to the Trier Social Stress Test

Previously, we observed enhanced long-term memory for objects used (central objects) by committee members in the Trier Social Stress Test (TSST) on the next day. In addition, startle responsivity was increased. However, response specificity to an odour involved in the stressful episode was lacking and recognition memory for the odour was poor. In the current experiments, immediate effects of the stressor on memory and startle responsivity were investigated. We hypothesised memory for central objects of the stressful episode and startle response specificity to an odour ambient during the TSST to be enhanced shortly after it, in contrast to the control condition (friendly TSST). Further, memory for this odour was also assumed to be increased in the stress group. We tested 70 male (35) and female participants using the TSST involving objects and an ambient odour. After stress induction, a startle paradigm including olfactory and visual stimuli was conducted. Indeed, memory for central objects was significantly enhanced in immediate aftermath of the stressor. Startle responsivity increased at a trend level, particularly with regard to the odour involved in the stressful episode. Moreover, the stress group descriptively tended towards a better recognition of the odour involved. The study shows that stress enhances memory for central aspects of a stressful situation before consolidation processes come into play. In addition, results preliminarily suggest that the impact of stress on startle responsivity increases in strength but decreases in specificity during the first 24h after stress exposure.

The role of eye fixation in memory enhancement under stress – An eye tracking study

In a stressful situation, attention is shifted to potentially relevant stimuli. Recent studies from our laboratory revealed that participants stressed perform superior in a recognition task involving objects of the stressful episode. In order to characterize the role of a stress induced alteration in visual exploration, the present study investigated whether participants experiencing a laboratory social stress situation differ in their fixation from participants of a control group. Further, we aimed at shedding light on the relation of fixation behaviour with obtained memory measures. We randomly assigned 32 male and 31 female participants to a control or a stress condition consisting of the Trier Social Stress Test (TSST), a public speaking paradigm causing social evaluative threat. In an established ‘friendly’ control condition (f-TSST) participants talk to a friendly committee. During both conditions, the committee members used ten office items (central objects) while another ten objects were present without being used (peripheral objects). Participants wore eye tracking glasses recording their fixations. On the next day, participants performed free recall and recognition tasks involving the objects present the day before. Stressed participants showed enhanced memory for central objects, accompanied by longer fixation times and larger fixation amounts on these objects. Contrasting this, fixation towards the committee faces showed the reversed pattern; here, control participants exhibited longer fixations. Fixation indices and memory measures were, however, not correlated with each other. Psychosocial stress is associated with altered fixation behaviour. Longer fixation on objects related to the stressful situation may reflect enhanced encoding, whereas diminished face fixation suggests gaze avoidance of aversive, socially threatening stimuli. Modified visual exploration should be considered in future stress research, in particular when focussing on memory for a stressful episode.

Structural overshoot of tree growth with climate variability and the global spectrum of drought-induced forest dieback.

Ongoing climate change poses significant threats to plant function and distribution. Increased temperatures and altered precipitation regimes amplify drought frequency and intensity, elevating plant stress and mortality. Large-scale forest mortality events will have far-reaching impacts on carbon and hydrological cycling, biodiversity, and ecosystem services. However, biogeographical theory and global vegetation models poorly represent recent forest die-off patterns. Furthermore, as trees are sessile and long-lived, their responses to climate extremes are substantially dependent on historical factors. We show that periods of favourable climatic and management conditions that facilitate abundant tree growth can lead to structural overshoot of aboveground tree biomass due to a subsequent temporal mismatch between water demand and availability. When environmental favourability declines, increases in water and temperature stress that are protracted, rapid, or both, drive a gradient of tree structural responses that can modify forest self-thinning relationships. Responses ranging from premature leaf senescence and partial canopy dieback to whole-tree mortality reduce canopy leaf area during the stress period and for a lagged recovery window thereafter. Such temporal mismatches of water requirements from availability can occur at local to regional scales throughout a species geographical range. As climate change projections predict large future fluctuations in both wet and dry conditions, we expect forests to become increasingly structurally mismatched to water availability and thus overbuilt during more stressful episodes. By accounting for the historical context of biomass development, our approach can explain previously problematic aspects of large-scale forest mortality, such as why it can occur throughout the range of a species and yet still be locally highly variable, and why some events seem readily attributable to an ongoing drought while others do not. This refined understanding can facilitate better projections of structural overshoot responses, enabling improved prediction of changes in forest distribution and function from regional to global scales.

Resilience as a strategy for struggling against challenges related to the nursing profession

Abstract Stressors, such as work overload, role conflicts, lack of time, lack of self-care, poor job-related interpersonal relationships, feeling powerless to provide quality care, struggling with competing demands, death, conflict with doctors, peers and supervisors, and inadequate emotional preparation, can be negative, stressful, traumatic, or difficult situations or episodes of hardship for nurses. Situations or episodes of these types can also cause both physical and mental problems, such as fatigue, irritability, lack of concentration, unhappiness, depressive sensation, depersonalization, and emotional exhaustion. Despite all of these challenges, resilience enables nurses to cope with their work environment and to maintain healthy and stable psychological functioning. The aim of this review is to describe the concept of resilience, explain characteristics with which it is related and outline interventions to increase the resilience of nurses.

Intestinal PPARγ signalling is required for sympathetic nervous system activation in response to caloric restriction

Nuclear receptor PPARγ has been proven to affect metabolism in multiple tissues, and has received considerable attention for its involvement in colon cancer and inflammatory disease. However, its role in intestinal metabolism has been largely ignored. To investigate this potential aspect of PPARγ function, we submitted intestinal epithelium-specific PPARγ knockout mice (iePPARγKO) to a two-week period of 25% caloric restriction (CR), following which iePPARγKO mice retained more fat than their wild type littermates. In attempting to explain this discrepancy, we analysed the liver, skeletal muscle, intestinal lipid trafficking, and the microbiome, none of which appeared to contribute to the adiposity phenotype. Interestingly, under conditions of CR, iePPARγKO mice failed to activate their sympathetic nervous system (SNS) and increase CR-specific locomotor activity. These KO mice also manifested a defective control of their body temperature, which was overly reduced. Furthermore, the white adipose tissue of iePPARγKO CR mice showed lower levels of both hormone-sensitive lipase, and its phosphorylated form. This would result from impaired SNS signalling and possibly cause reduced lipolysis. We conclude that intestinal epithelium PPARγ plays an essential role in increasing SNS activity under CR conditions, thereby contributing to energy mobilization during metabolically stressful episodes.

Enhanced startle responsivity 24 hours after acute stress exposure.

Cortisol release in a stressful situation can be beneficial for memory encoding and memory consolidation. Stimuli, such as odors, related to the stressful episode may successfully cue memory contents of the stress experience. The current investigation aimed at testing the potency of stress to influence startle responsivity 24 hr later and to implicitly reactivate emotional memory traces triggered by an odor involved. Participants were assigned to either a stress (Trier Social Stress Test [TSST]) or control (friendly TSST [f-TSST]) condition featuring an ambient odor. On the next day, participants underwent an auditory startle paradigm while their eyeblink reflex was recorded by an electrooculogram. Three different olfactory stimuli were delivered, one being the target odor presented the day before. Additionally, negative, positive, and pictures of the committee members were included for comparing general startle responsivity and fear-potentiated startle. Participants of the stress group demonstrated an enhanced startle response across all stimuli compared to participants of the control group. There were no specific effects with regard to the target odor. The typical fear-potentiated startle response occurred. Stressed participants tended to rate the target odor more aversive than control participants. Odor recognition memory did not differ between the groups, suggesting an implicit effect on odor valence. Our results show that acute stress exposure enhances startle responsivity 24 hr later. This effect might be caused by a shift of amygdala function causing heightened sensitivity, but lower levels of specificity. (PsycINFO Database Record

Mobilising citizen scientists to monitor rapidly changing acid sulfate soils

ABSTRACTDrought culminating in 2009 in the Murray–Darling Basin put severe downstream pressure on Lakes Alexandrina and Albert (“Lower Lakes”) in South Australia. Falling water levels caused sulfidic acid sulfate soils (ASS) to dry forming sulfuric ASS (pH < 4) in lakebeds, along with environmental, economic and public health concerns. The pace of sulfuric ASS spread overwhelmed scientific efforts to develop robust hydrogeochemical models for the best management decisions. Meanwhile, community impatience grew because of fears for livelihoods, public health and loss of recreational amenity and exacerbated by apparent slow pace of government response caused by lagging scientific support. Responding to the looming problems, government, community and scientists joined in a citizen science project. The project comprised a programme of community ASS education, training and a field sampling programme conducted over four intervals (August 2009–June 2010). The project attracted 84 volunteers who sampled 51 survey areas covering the full range of ASS. The citizen scientists allowed a wider geographic and temporal sampling reach than was otherwise possible by scientists alone. The citizen scientists amplified the work of scientists by adding to the pool of data and freeing scientists to concentrate on non-routine ASS work. Perhaps of more enduring importance, the project showed how community, government and scientists can cooperate at times of environmental stress. The experience has grown government’s capability to implement policy to grow community resilience during environmentally stressful episodes. Finally, the Lower Lakes community is now positioned for the next drought because community knowledge, leadership and networks are now in place.

Finding Significant Stress Episodes in a Discontinuous Time Series of Rapidly Varying Mobile Sensor Data.

Management of daily stress can be greatly improved by delivering sensor-triggered just-in-time interventions (JITIs) on mobile devices. The success of such JITIs critically depends on being able to mine the time series of noisy sensor data to find the most opportune moments. In this paper, we propose a time series pattern mining method to detect significant stress episodes in a time series of discontinuous and rapidly varying stress data. We apply our model to 4 weeks of physiological, GPS, and activity data collected from 38 users in their natural environment to discover patterns of stress in real-life. We find that the duration of a prior stress episode predicts the duration of the next stress episode and stress in mornings and evenings is lower than during the day. We then analyze the relationship between stress and objectively rated disorder in the surrounding neighborhood and develop a model to predict stressful episodes.

Psychological Impact of Mizoram Insurgency

This study was designed to investigate the psychological effect of insurgency in the Mizo, caused by the 20 years insurgency in Mizoram. To meet the objectives 200 Mizo participants were randomly selected, who had experienced that stressful situations at different levels of exposures to the stressful episodes. The study examines level of anxiety, depression, anger-hostility, somatic-concern and frustration of the insurgency effected people in Mizoram. It was found that those who had experience combat at first hand and fatal episode were the most vulnerable to psychological problems.

Depressive vulnerability, stressful life events and episode onset of major depression: a longitudinal model.

The nature of the relationship between depressive vulnerability (DV) and acute adversity in the etiology of major depression (MD) remains poorly understood. Stressful life events (SLEs) and MD onsets in the last year were assessed at four waves in cohort 1 (females) and at two waves in cohort 2 (males and females) from the Virginia Adult Twin Study. Structural equation modeling was conducted in Mplus. In cohort 1, DV was strongly indexed by depressive episodes over the four waves (paths from +0.72 to 0.79) and predicted by SLEs in the month of their occurrence (+0.31 to 0.36). Wave-specific DV was associated both with stable DV (+0.29 to 0.33) and by forward transmission of DV from the preceding wave (+0.33 to 0.36). SLEs were predicted by stable DV (+0.29) and from SLEs in the preceding month (+0.06). As the cohort aged, MD onsets were better indexed by DV and more poorly predicted by SLEs. Parameter estimates were similar in males and females from cohort 2. In individuals with prior depressive episodes, the association between MD onset and SLEs was weakened while the prediction of SLEs from DV was substantially strengthened. We found no evidence for 'reverse causation' from MD episodes to SLEs. The interrelationship between DV and acute adversity in the etiology of MD is complex and temporally dynamic. DV impacts on MD risk both directly and indirectly through selection into high stress environments. Over time, depressive episodes become more autonomous. Both DV and SLEs transmit forward over time and therefore form clear targets for intervention.

Impact of acute stress on psychomotor bimanual performance during a simulated tumor resection task.

OBJECTIVE Severe bleeding during neurosurgical operations can result in acute stress affecting the bimanual psychomotor performance of the operator, leading to surgical error and an adverse patient outcome. Objective methods to assess the influence of acute stress on neurosurgical bimanual psychomotor performance have not been developed. Virtual reality simulators, such as NeuroTouch, allow the testing of acute stress on psychomotor performance in risk-free environments. Thus, the purpose of this study was to explore the impact of a simulated stressful virtual reality tumor resection scenario by utilizing NeuroTouch to answer 2 questions: 1) What is the impact of acute stress on bimanual psychomotor performance during the resection of simulated tumors? 2) Does acute stress influence bimanual psychomotor performance immediately following the stressful episode? METHODS Study participants included 6 neurosurgeons, 6 senior and 6 junior neurosurgical residents, and 6 medical students. Participants resected a total of 6 simulated tumors, 1 of which (Tumor 4) involved uncontrollable "intraoperative" bleeding resulting in simulated cardiac arrest and thus providing the acute stress scenario. Tier 1 metrics included extent of blood loss, percentage of tumor resected, and "normal" brain tissue volume removed. Tier 2 metrics included simulated suction device (sucker) and ultrasonic aspirator total tip path length, as well as the sum and maximum forces applied in using these instruments. Advanced Tier 2 metrics included efficiency index, coordination index, ultrasonic aspirator path length index, and ultrasonic aspirator bimanual forces ratio. All metrics were assessed before, during, and after the stressful scenario. RESULTS The stress scenario caused expected significant increases in blood loss in all participant groups. Extent of tumor resected and brain volume removed decreased in the junior resident and medical student groups. Sucker total tip path length increased in the neurosurgeon group, whereas sucker forces increased in the senior resident group. Psychomotor performance on advanced Tier 2 metrics was altered during the stress scenario in all participant groups. Performance on all advanced Tier 2 metrics returned to pre-stress levels in the post-stress scenario tumor resections. CONCLUSIONS Results demonstrated that acute stress initiated by simulated severe intraoperative bleeding significantly decreases bimanual psychomotor performance during the acute stressful episode. The simulated intraoperative bleeding event had no significant influence on the advanced Tier 2 metrics monitored during the immediate post-stress operative performance.

A case study of vocal features associated with galvanic skin response to stressors in a clinical interaction

ObjectiveWe investigated vocal characteristics associated with physiologically determined stressful episodes by means of post-hoc acoustic analyses of speech recorded in a clinical setting. Our research addressed the understudied question of which vocal features may serve as cues naturally occurring stress and is the first to explore this issue in a pitch accent language. MethodsThe vocal profile of a single female patient interacting with a physician was analyzed with standard speech analysis software for acoustic indicators of stress-related arousal determined by galvanic skin response measurements. ResultsVocal jitter, representing an aspect of voice quality perceived as hoarseness, appeared to increase during and immediately after skin conductance response intervals. Skin conductance levels during the response intervals were negatively correlated with acoustic features used to approximate the perception of voice unsteadiness (slope and standard deviation of fundamental frequency). ConclusionAn acoustic analysis of vocal properties of speech uttered during independently detected skin conductance response intervals revealed individual patterns for some acoustic features linked to stress in earlier studies. Practice implicationsNon-invasive methods of arousal detection in physician-patient communication based on acoustic analyses of vocal profiles may, in combination with other analyses, help identify stressful events and thus improve the process of medical information gathering and decision-making.

Happy heart syndrome: role of positive emotional stress in takotsubo syndrome.

AimsTakotsubo syndrome (TTS) is typically provoked by negative stressors such as grief, anger, or fear leading to the popular term ‘broken heart syndrome’. However, the role of positive emotions triggering TTS remains unclear. The aim of the present study was to analyse the prevalence and characteristics of patients with TTS following pleasant events, which are distinct from the stressful or undesirable episodes commonly triggering TTS.Methods and resultsTakotsubo syndrome patients with preceding pleasant events were compared to those with negative emotional triggers from the International Takotsubo Registry. Of 1750 TTS patients, we identified a total of 485 with a definite emotional trigger. Of these, 4.1% (n = 20) presented with pleasant preceding events and 95.9% (n = 465) with unequivocal negative emotional events associated with TTS. Interestingly, clinical presentation of patients with ‘happy heart syndrome’ was similar to those with the ‘broken heart syndrome’ including symptoms such as chest pain [89.5% (17/19) vs. 90.2% (412/457), P = 1.0]. Similarly, electrocardiographic parameters, laboratory findings, and 1-year outcome did not differ. However, in a post hoc analysis, a disproportionate higher prevalence of midventricular involvement was noted in ‘happy hearts’ compared with ‘broken hearts’ (35.0 vs. 16.3%, P = 0.030).ConclusionOur data illustrate that TTS can be triggered by not only negative but also positive life events. While patient characteristics were similar between groups, the midventricular TTS type was more prevalent among the ‘happy hearts’ than among the ‘broken hearts’. Presumably, despite their distinct nature, happy and sad life events may share similar final common emotional pathways, which can ultimately trigger TTS.

Seeding Stress Resilience through Inoculation.

Stress is a generalized set of physiological and psychological responses observed when an organism is placed under challenging circumstances. The stress response allows organisms to reattain the equilibrium in face of perturbations. Unfortunately, chronic and/or traumatic exposure to stress frequently overwhelms coping ability of an individual. This is manifested as symptoms affecting emotions and cognition in stress-related mental disorders. Thus environmental interventions that promote resilience in face of stress have much clinical relevance. Focus of the bulk of relevant neurobiological research at present remains on negative aspects of health and psychological outcomes of stress exposure. Yet exposure to the stress itself can promote resilience to subsequent stressful episodes later in the life. This is especially true if the prior stress occurs early in life, is mild in its magnitude, and is controllable by the individual. This articulation has been referred to as “stress inoculation,” reminiscent of resilience to the pathology generated through vaccination by attenuated pathogen itself. Using experimental evidence from animal models, this review explores relationship between nature of the “inoculum” stress and subsequent psychological resilience.