Showing papers on "Stressor published in 2007"

If it goes up, must it come down? Chronic stress and the hypothalamic-pituitary-adrenocortical axis in humans.

Abstract: The notion that chronic stress fosters disease by activating the hypothalamic-pituitary-adrenocortical (HPA) axis is featured prominently in many theories. The research linking chronic stress and HPA function is contradictory, however, with some studies reporting increased activation, and others reporting the opposite. This meta-analysis showed that much of the variability is attributable to stressor and person features. Timing is an especially critical element, as hormonal activity is elevated at stressor onset but reduces as time passes. Stressors that threaten physical integrity, involve trauma, and are uncontrollable elicit a high, flat diurnal profile of cortisol secretion. Finally, HPA activity is shaped by a person's response to the situation; it increases with subjective distress but is lower in persons with posttraumatic stress disorder.

Differential challenge stressor-hindrance stressor relationships with job attitudes, turnover intentions, turnover, and withdrawal behavior: A meta-analysis

Abstract: In this article, a 2-dimensional work stressor framework is used to explain inconsistencies in past research with respect to stressor relationships with retention-related criteria. Results of meta-analyses of 183 independent samples indicated that whereas hindrance stressors had dysfunctional relationships with these criteria (negative relationships with job satisfaction and organizational commitment and positive relationships with turnover intentions, turnover, and withdrawal behavior), relationships with challenge stressors were generally the opposite (positive relationships with job satisfaction and organizational commitment and negative relationships with turnover intentions and turnover). Results also suggested that the differential relationships between challenge stressors and hindrance stressors and the more distal criteria (withdrawal behavior and turnover) were due, in part, to the mediating effects of job attitudes.

Stress and memory: behavioral effects and neurobiological mechanisms.

Abstract: Stress is a potent modulator of learning and memory processes. Although there have been a few attempts in the literature to explain the diversity of effects (including facilitating, impairing, and lack of effects) described for the impact of stress on memory function according to single classification criterion, they have proved insufficient to explain the whole complexity of effects. Here, we review the literature in the field of stress and memory interactions according to five selected classifying factors (source of stress, stressor duration, stressor intensity, stressor timing with regard to memory phase, and learning type) in an attempt to develop an integrative model to understand how stress affects memory function. Summarizing on those conditions in which there was enough information, we conclude that high stress levels, whether intrinsic (triggered by the cognitive challenge) or extrinsic (induced by conditions completely unrelated to the cognitive task), tend to facilitate Pavlovian conditioning (in a linear-asymptotic manner), while being deleterious for spatial/explicit information processing (which with regard to intrinsic stress levels follows an inverted U-shape effect). Moreover, after reviewing the literature, we conclude that all selected factors are essential to develop an integrative model that defines the outcome of stress effects in memory processes. In parallel, we provide a brief review of the main neurobiological mechanisms proposed to account for the different effects of stress in memory function. Glucocorticoids were found as a common mediating mechanism for both the facilitating and impairing actions of stress in different memory processes and phases. Among the brain regions implicated, the hippocampus, amygdala, and prefrontal cortex were highlighted as critical for the mediation of stress effects.

Childhood Poverty and Health Cumulative Risk Exposure and Stress Dysregulation

Abstract: A massive literature documents the inverse association between poverty or low socioeconomic status and health, but little is known about the mechanisms underlying this robust relation. We examined longitudinal relations between duration of poverty exposure since birth, cumulative risk exposure, and physiological stress in two hundred seven 13-year-olds. Chronic stress was assessed by basal blood pressure and overnight cortisol levels; stress regulation was assessed by cardiovascular reactivity to a standard acute stressor and recovery after exposure to this stressor. Cumulative risk exposure was measured by multiple physical (e.g., substandard housing) and social (e.g., family turmoil) risk factors. The greater the number of years spent living in poverty, the more elevated was overnight cortisol and the more dysregulated was the cardiovascular response (i.e., muted reactivity). Cardiovascular recovery was not affected by duration of poverty exposure. Unlike the duration of poverty exposure, concurrent poverty (i.e., during adolescence) did not affect these physiological stress outcomes. The effects of childhood poverty on stress dysregulation are largely explained by cumulative risk exposure accompanying childhood poverty.

Making sense of apparently conflicting data: stress and immunity in swine and cattle.

Abstract: Stress is generally considered to suppress the immune system and may lead to an increase in the occurrence of disease in the presence of a pathogen. The immune system is ordinarily brought back to a baseline response level after immune challenge through homeostatic processes, in part regulated by the hypothalamic-pituitary-axis. Often, findings reported from various studies investigating the effects of stress on the immune system are conflicting and difficult to reconcile into a cohesive and comprehensible set of universally applicable theories. These discrepancies may be partly explained by the types and durations of the stressors, the aspect(s) of immune system measured, genetics, and social status. A particular stressor may enhance cell-mediated immune responses while suppressing humoral responses or vice versa, thus disrupting the balance between these components of the immune system. How farm animals perceive their environment depends not only on traditional environmental stressors (e.g., heat, cold, humidity, pollutants), but also on aspects of their social environment. Dominant animals may have enhanced immune activation, whereas subordinates have suppression of the same immune component in response to the same stressor. This could explain why individual animals within a group respond differently to stressors and disease challenges. A better understanding of the consequences and complex interactions between social and environmental stressors for innate and adaptive immune traits must be developed so we can more fully understand the effects of stress on immunity in livestock. Once these complex relationships are better understood, more effective interventions can be designed to improve animal health and well-being.

Acute Psychosocial Stress Reduces Cell Survival in Adult Hippocampal Neurogenesis without Altering Proliferation

Abstract: Factors modulating neurogenesis may contribute to the pathophysiology of affective disorders such as major depression. Environmental stressors in animal models have been proposed to alter neurogenesis, suggesting a mechanism for this contribution. The effect of an acute psychosocial stressor on either proliferation or survival (immediate, short term, and long term) was examined along with subsequent neuronal differentiation in the hippocampus of adult male Sprague Dawley rats. Subjects were exposed to a widely used social dominance paradigm that elicits behavioral and physiological responses to an acute psychosocial stressor. This social dominance paradigm may mimic human relational stress more realistically than laboratory stressors and provides a socially relevant model. We found that exposure to an acute psychosocial stressor at the time of cell generation resulted in a decreased number of newly generated cells in the hippocampus. By using sequential thymidine analog administration to provide temporal discrimination of DNA replication, we showed that short-term survival but not initial proliferation or immediate survival was altered in response to stress. Furthermore, we determined that stress experienced subsequent to proliferation also diminished long-term survival of cells. Thus, an acute episode of a social stress produces long-lasting effects on the incorporation of new hippocampal neurons by reducing their survival.

Biology and therapy of fibromyalgia. Stress, the stress response system, and fibromyalgia

Abstract: Stress is a state of disharmony, or threatened homeostasis. A stressor could have a psychological origin or a biological origin. Societies have become more intricate with industrialization, and modern individuals try to adapt to the new defiance by forcing their stress response system. The main component of the stress response network is the autonomic nervous system. The present article reviews current knowledge on autonomic dysfunction in fibromyalgia. Sympathetic hyperactivity has been consistently described by diverse groups of investigators. Fibromyalgia is proposed to be a sympathetically maintained neuropathic pain syndrome, and genomic data support this contention. Autonomic dysfunction may also explain other fibromyalgia features not related to pain.

The caregiver stress process and health outcomes.

Abstract: Objective: The authors examine the impact of two caregiving stressors, care receivers' behavior problems (an objective stressor) and caregivers' feelings of overload (a subjective stressor), on three dimensions of caregiver health. Method: The participants were 234 primary caregivers of elderly relatives with dementia living in the community who completed a comprehensive interview about their current care situation, including stressors and health. Results: Higher levels of both objective and subjective stressors were associated with all three dimensions of caregiver health: poorer self-reported health, more negative health behaviors, and greater use of health care services. The association between objective stressors and health was mediated by caregivers' feelings of overload. Conclusions: These findings demonstrate caregivers' vulnerability to the effects of stressors across three dimensions of health and also underscore the importance of subjective appraisals of stress.

Stress and Burnout Among Prison Personnel: Sources, Outcomes, and Intervention Strategies

Abstract: This study identifies the typical stressors affecting individuals working in the prison system in Israel and assesses the outcomes resulting from these stressors. A representative sample of Israel ...

College student stress: the influence of interpersonal relationships on sense of coherence

Abstract: The purpose of this study was to investigate college student stress, how students cope with stress, and how the stress of renegotiating self and relationships influences one's sense of coherence (SOC). A survey research design was utilized incorporating 596 college students. Using family stress theory, this study examined how stress associated with relationships, level of coping, physical and emotional reactions to stress, and quality of life can be integrated to predict SOC in male and female college students. Findings indicate that female college students experience greater stress from quality of friendships, love relationships and relationships with parents. Whereas emotional health had the greatest effect on SOC for females, family relationships had the greatest effect on SOC for males. Qualitative responses were also examined, providing insight into students' perceptions of stressors. Conclusions and implications for educators, researchers and family therapists are discussed. Copyright © 2007 John Wiley & Sons, Ltd.

Endocrinology of Stress

Abstract: When an animal detects a stressor, it initiates a stress response. The physiological aspects of this stress response are mediated through two endocrine systems. The catecholamine hormones epinephrine and norepinephrine are released from the adrenal medulla very rapidly and have numerous effects on behavior, metabolism, and the cardiovascular system. This is commonly termed the Fight-or-Flight response. On a longer time scale, the glucocorticoid hormones are released from the adrenal cortex. They interact with intracellular receptors and initiate gene transcription. This production of new proteins means that glucocorticoids have a delayed, but more sustained, effect than the catecholamines. The glucocorticoids orchestrate a wide array of responses to the stressor. They have direct effects on behavior, metabolism and energy trafficking, reproduction, growth, and the immune system. The sum total of these responses is designed to help the animal survive a short-term stressful stimulus. However, under conditions of long-term stress, the glucocorticoid-mediated effects become maladaptive and can lead to disease. Stress, as originally coined by Selye (1946), has been the subject of study for decades. It became quickly apparent that the term “stress” actually encompasses three related topics: changes/stimuli from the environment that cause “stress” (subsequently called stressors); the physiological and psychological responses to those stimuli (subsequently called the stress response); and the diseases that result from an overstimulation of the physiological and psychological responses (subsequently called chronic stress effects). Research has focused on all three of these concepts. An enormous amount is now known about what stimuli elicit which physiological and psychological responses. We also know many of the mechanisms whereby various hormonal mediators compromise organ, tissue, and cellular function (Fink, 2007). This paper will provide a brief overview of what is known about the endocrine responses to stressors. The following general information is broadly known and widely presented. Most of the information comes from the following sources (McEwen & Goodman, 2001; Nelson, 2005; Norman & Litwack, 1997; Norris, 2007; Sapolsky, Romero, & Munck, 2000) and interested readers should consult them for more detail. Specific information and individual studies are cited independently. Although there are many hormones that have been identified as playing a role in the vertebrate stress response, two categories of hormones are thought to form the central components of the endocrine response. These are the catecholamines, epinephrine and norepinephrine (also known as adrenalin and noradrenalin) and the glucocorticoids. Together, these hormones help to orchestrate the body’s stress response. How they do so is presented below.

Stress, self-efficacy and quality of life in cancer patients.

Abstract: The purpose of the study was to examine the effect of different stressors on various domains of quality of life (QOL) in cancer patients. The study focused on testing a model describing interrelations between two kinds of stress antecedents, two mediating variables--perceived stress and self-efficacy--and QOL. The participants were 60 cancer patients of both genders and various diagnoses. They were administered questionnaires of background information, QOL, perceived stress and general self-efficacy. Two stress indices were defined empirically: health stress (based on advanced disease stage, long disease duration, and undergoing treatment) and social stress (based on unemployment, recent immigration, and older age). Confirmatory factor analysis enabled defining five factors of QOL. Hierarchical regression analyses showed that the index of social stress was related to more QOL scales than the index of health stress and very few interactions with the mediating variables. Structural equation modeling provided a more comprehensive and accurate view. It showed that the index of health stress affected QOL mainly through perceived stress, and that self-efficacy affected QOL by reducing perceived stress and increasing QOL. The major conclusions are that QOL is affected negatively by both health stresses and social stresses, but the former are mediated primarily by the experience of perceived stress.

Anthropogenic Noise as a Stressor in Animals: A Multidisciplinary Perspective

Abstract: This paper could not have been written without the financial and organizational support from Dieter Paulmann and Jo Hastie respectively. Thanks are also due to 2 anonymous reviewers, whose comments on an earlier version of the manuscript greatly improved the paper. The views expressed in this paper are those of the authors alone and do not represent those of Stellwagen Bank National Marine Sanctuary, the U.S. National Marine Sanctuary Program, Southwest Fisheries Science Center, the U.S. National Marine Fisheries Service, NOAA and/or any other institution or agency. Correspondence concerning this article should be addressed to Andrew Wright, Leviathan Sciences, U.S.A. (marinebrit@gmail.com). Consequences of extreme noise exposure are obvious and usually taken into some consideration in the management of many human activities that affect either human or animal populations. However, the more subtle effects such as masking, annoyance and changes in behavior are often overlooked, especially in animals, because these subtleties can be very difficult to detect. To better understand the possible consequences of exposure to noise, this review draws from the available information on human and animal physiology and psychology, and addresses the importance of context (including physiological and psychological state resulting from any previous stressor exposure) in assessing the true meaning of behavioral responses. The current consensus is that the physiological responses to stressors of various natures are fairly stereotyped across the range of species studied. It is thus expected that exposure to noise can also lead to a physiological stress response in other species either directly or indirectly through annoyance, a secondary stressor. In fact many consequences of exposure to noise can result in a cascade of secondary stressors such as increasing the ambiguity in received signals or causing animals to leave a resourceful area, all with potential negative if not disastrous consequences. The context in which stressors are presented was found to be important not only in affecting behavioral responses, but also in affecting the physiological and psychological responses. Young animals may be particularly sensitive to stressors for a number of reasons including the sensitivity of their still-developing brains. Additionally, short exposure to stressors may result in long-term consequences. Furthermore, physiological acclimation to noise exposure cannot be determined from apparent behavioral reactions alone due to contextual influence, and negative impacts may persist or increase as a consequence of such behavioral changes. Despite the lack of information available to managers, uncertainty analysis and modeling tools can be coupled with adaptive management strategies to support decision making and continuous improvements to managing the impacts of noise on free-ranging animals.

Stressors, coping, and coping effectiveness: gender, type of sport, and skill differences

Abstract: The aim of this study was to examine stressors, coping, and coping effectiveness as a function of gender, type of sport, and skill. The sample consisted of 749 undergraduate athletes (455 males, 294 females) aged 18 – 38 years (mean = 19.8 years). Skill was classified as international/national, county, university, and club standard. Participants completed a stressor and coping concept map (Novak & Gowin, 1984). The results revealed gender, type of sport, and skill differences in relation to stressor frequencies, coping strategy deployment, and coping effectiveness. In contrast to previous research, females used a variety of problem-focused (e.g. planning, communication, technique-orientated coping) strategies more frequently than males. Team sport athletes reported a variety of sport-specific stressors relating to the demands of playing in a team environment. The group of national/international athletes reported using more planning, blocking, and visualization, and also reported that their coping was more effective than that of less-skilled athletes.

Stress increases attentional bias for alcohol cues in social drinkers who drink to cope.

Abstract: Aims: To investigate the effects of stress on alcohol craving and attentional bias for alcohol-related cues in a group of heavy social drinkers. Method: Forty-four heavy social drinkers were exposed to either a laboratory stressor task or a control manipulation before completing a questionnaire measure of alcohol craving and a visual probe task which measured attentional bias for alcohol-related cues. Participants were subdivided into those with high and low levels of coping motives for drinking. Results: Compared to a control manipulation, the laboratory stressor task produced increases in alcohol craving ( P < 0.01). The laboratory stressor task also produced a significant attentional bias for alcohol-related cues, but only among participants who had high levels of coping motives ( P < 0.05). Conclusions: Findings are broadly consistent with contemporary negative reinforcement models of substance abuse, and with models of subjective craving and attentional biases for substance-related cues.

Coping and Adjustment in Children with Cancer: A Meta-Analytic Study

Abstract: The current meta-analysis assessed the efficacy of coping strategies on psychological and physical adjustment in children with cancer (n = 1230). Coping strategies were operationalized in accordance with two coping taxonomies; the first is based on the general orientation of the child's coping attempts (approach or avoidance), and the second is based upon coping efforts to regulate the stressor and/or feelings of distress attributed to it (problem-focused and emotion-focused). Approach, avoidance, and emotion-focused coping were unrelated to overall adjustment. A small-to-medium but negative association was found between problem-focused coping and adjustment, indicating more use of the strategies that compose this dimension are associated with poorer adjustment. However, homogeneity analyses also indicated significant variation for all of these effect sizes. Follow-up moderator analyses found coping-adjustment relations were both dependent upon time since diagnosis and the particular stressor the child was dealing with during treatment.

Perceived emotional intelligence facilitates cognitive-emotional processes of adaptation to an acute stressor

Abstract: This study examined the influence of perceived emotional intelligence (PEI) and intrusive thoughts on emotional responses following a stressful event. PEI was assessed on 144 participants using the Trait Meta-Mood Scale (TMMS). The TMMS assesses perceived ability to: (1) attend to moods (Attention); (2) discriminate clearly among moods (Clarity); and (3) regulate moods (Repair). The main purpose of this paper was to examine the relationship between PEI, intrusive thoughts, and adjustment to an acute stressor induced experimentally in the laboratory, on two separate days. Finally, we examined the relationship between PEI, Inhibition, and Empathy. Results indicated that Clarity influences emotional responses on Day 1, and Repair affects emotional responses on Day 2 indirectly via intrusive thoughts, which act as a mediator. Significant associations were obtained between the three factors of the TMMS with Empathy and Inhibition. These findings suggest that individuals with higher emotional Clarity and Repair will experience less negative emotional responses and intrusive thoughts after an acute stressor, which enables them to adapt more readily to the experience. Perceived emotional intelligence and acute stressors

Protecting and promoting mental health in the workplace: developing a systems approach to job stress.

Abstract: Issue addressed: Job stress has been linked to a wide range of adverse effects on mental, physical, and organisational health. Despite the evidence that systems approaches are most effective in reducing the adverse impact of job stress, prevalent practice is dominated by worker- or individual-focused strategies in the absence of commensurate intervention on working conditions. Methods: A literature review and cross-disciplinary conceptual synthesis were combined in the articulation of a systems approach to job stress. Results: An outline of the job stress process is followed by explanation of how a systems approach addresses the various steps in the stress process. Systems approaches to job stress emphasise primary prevention or focusing on stressors as the upstream determinants of job stress. Additionally, systems approaches integrate primary with worker-directed secondary and illness-directed tertiary intervention, include the meaningful participation of groups targeted by intervention, and are context- sensitive. Systems approach intervention principles are illustrated by concrete examples of intervention strategies and activities. Conclusions: Further efforts are needed to promote, disseminate, implement, and evaluate systems approaches to job stress and to improve cross-disciplinary cooperation in this effort. (author abtract)