Male and female psychoneuroendocrine response to examination stress: A case report

Urinary catecholamine levels were investigated in one female and one male Ph.D. candidate during public defense of their Ph.D. theses as well as during 2 weeks preceding and 1 week following these examinations. Although females, in comparison to males, usually tend to show a weak adrenaline response to mental stress, a threefold increase was observed in both subjects. The results support the assumption that sex differences in adrenal-medullary responsiveness to stress is not determined by sex-specific biological factors alone and that a “male” responsiveness may be observed in achievement-oriented females exposed to a challenging real-life situation. Effects on urinary measures of cortisol obtained from the male subject resembled effects on adrenaline, showing that this kind of real-life stressor affects the sympathetic-adrenal medullary and the pituitary-adrenocortical systems similarly.     

Coping Strategies in Adolescents

Children and adolescents report that they experience stress in their lives and that they attempt to cope with that stress. Although most research on stress and coping has focused on adults, recent attention to adolescents suggests there are developmental changes in coping during adolescence and that particular coping strategies vary with gender and the type of stressors adolescents experience. This study examined coping strategies used by male and female students in early, middle, and late adolescence when they were coping with two different types of stressors: daily hassles and major life events. Older adolescents used a greater variety coping strategies and used methods that directly reduce the impact of the stressor and involved a cognitive component (e.g., planful problem solving; reappraisal) more often than younger adolescents. Adolescents in all age groups varied their strategies in relation to the type of stressor, but there were no significant gender differences. The findings suggest that significant changes during a relatively short period during adolescence may affect adaptive processes and have implications for intervention efforts aimed at reducing the negative effects of stress during this period of development.     

青少年地震应激反应模型

以亲历“5．12”地震的四川青川、绵竹327名青少年为被试,考察了青少年在地震情境下的应激反应,探讨了应激源与认知评价、应对方式、应激反应的关系,检验了认知评价、应对方式在应激源与应激反应间的中介作用。结果表明：青少年在地震后出现一些显著的生理反应（胸闷、食欲不佳、头晕）、心理反应（悲伤、易惹、恐惧、注意力减退）以及社会功能的退缩,且存在显著的性别差异;变量各维度间的相关分析表明,除混合型应对方式与应激源的物质丧失之间相关不显著外,其它变量各维度间均存在不同程度的相关;中介效应分析表明,认知评价、应对方式在应激源与应激反应间存在中介作用,且认知评价的中介效应大于应对方式的中介效应,而认知评价又可以通过应对方式影响应激反应。     

The impact of cortisol reactivity to acute stress on memory: sex differences in middle-aged people

Stress has been identified as a main factor involved in the cognitive changes that occur during the aging process. This study investigated sex differences in the relationship between the magnitude of the acute stress-induced salivary cortisol response and memory performance among middle-aged people. To this end, 16 men and 16 women (aged 54-72 years) were exposed to the Trier Social Stress Test and a control condition in a crossover design. Afterwards their memory performance was measured using a standardized memory test (Rey's Auditory Verbal Learning Test). Only among women, there was an acute impact of stress on memory performance and a significant relationship between a higher cortisol response to the stressor and poorer memory performance in both the stress and control conditions. Additionally, a poorer memory performance was related to earlier timing of sexual maturation (age at menarche), which was also marginally related to higher cortisol reactivity to stress. These results confirm that sex is a critical factor in the relationship between cortisol and poor memory performance. Furthermore, the findings emphasize a strong link between the individual cortisol response to stress and memory functioning among postmenopausal women.     

The effects of exposure to an acute naturalistic stressor on working memory, state anxiety and salivary cortisol concentrations

Exposure to an acute naturalistic stressor induces both psychological and physiological changes in humans. The two studies reported here explored the impact of exposure to an acute naturalistic stressor on state anxiety, working memory and HPA axis activation (salivary cortisol). In both experiments, ten healthy male participants were exposed to an acute naturalistic stressor, helicopter underwater evacuation training (HUET), and their physiological and behavioural responses before (first study) and after (second study) the stressor were compared to ten non-stressed controls. The results of both experiments showed that working memory performance was preserved during anticipation of an acute stressor, but impairments were observed immediately after stress exposure. Participants reported significantly higher state anxiety levels during anticipation and following stress exposure, whereas significant elevations in cortisol levels were only observed 25 min post exposure to stress, but not before or immediately after stress exposure. The results of both experiments demonstrated a dissociation between behavioural and biochemical measures and provided evidence for a dissociation of the effects of stress on cognitive and physiological measures depending on the time of testing, with cognitive impairments most evident following stress exposure.     

Sex differences in chronic stress effects on memory in rats

Recent studies in rodent models and in humans have shown that the status of both the gonadal and adrenal axes (hypothalamic-pituitary-gonadal, HPG and hypothalamic-pituitary-adrenal, HPA, respectively) can influence learning and memory function. In this article, the effects of activating the HPA axis (stress) on performance of memory tasks in rats are reviewed. More importantly, results are presented which show that chronic stress has a different impact on performance of these tasks depending upon the sex of the rat. These observations are novel and potentially important since few studies, animal or human, have utilized females as subjects in studies of the stress response. Sex differences in the effects of chronic stress on memory were investigated in rats using an object recognition task and two spatial memory tasks, radial arm maze and object location. Given the same chronic stress--21 days of restraint for 6 h each day--males were impaired in all of the memory tests while females showed enhanced performance of the spatial memory tasks and no changes in object recognition performance. Levels of neurotransmitters and metabolites were measured in brain areas important for cognition in the subjects in order to determine neural systems that may respond to stress and mediate the cognitive responses. These results show that responses of monoamine and amino acid containing neural systems may contribute to or underlie sex differences in stress effects on cognition. Stress decreased dopaminergic activity in the frontal cortex and amygdala of males but not females; whereas, in CA3 of the hippocampus, stress increased levels of 5-HT and norepinephrine in females, but not males, and increased GABA in males, but not females. Finally, a possible role for estradiol in mediating sexually differentiated responses to stress was examined. Behavioral and neurochemical evaluations in ovariectomized, stressed females, with or without estrogen replacement, suggest that sex differences in response to stress are influenced by both the organizing and activating effects of estradiol. A few, recent studies in humans, that show sexually dimorphic relationships between chronic stress and cognition, are also highlighted. These results in humans are consistent with the pattern of results in rats. Clearly, further studies are necessary to substantiate sex differences in stress effects on memory function in humans and to understand mechanisms whereby estrogen may influence the stress response in rats. Nonetheless, recent studies show sexually differentiated cognitive responses to chronic stress and underline the importance of considering the sex/gender of subjects when studying the stress response.     

Sex differences in cardiovascular reactivity: effects of the gender relevance of the stressor.

Suggests that sex differences in cardiovascular reactivity (CVR) in past research are a function of differences in cognitive appraisal of stressors as masculine or feminine tasks. In the present study, we examined the role of the gender relevance of the stressor as a mediator of sex differences in CVR. The CVR of male and female college students (n = 95) to the cold pressor test (CPT) was compared under masculine and gender-neutral instructions during an anticipation phase, a stressor phase, and a recovery phase. Men were expected to show greater CVR than women to the masculine CPT but not to the gender-neutral CPT. Results supported this prediction for systolic blood pressure reactivity and heart rate reactivity but not for diastolic blood pressure reactivity. The potential influence of sex differences in appraisal of situations on CVR and coronary heart disease is discussed.     

Alcohol use and stress in women: The role of prior vs. anticipated stressors

The present study investigated stress-related drinking in women. Alcohol consumption in response to stress and in anticipation of a stressor was examined to evaluate women's use of alcohol to cope with stress. Subjects were assigned to one of four conditions in a 2 × 2 factorial design in which order of alcohol consumption and stress task as well as stress level was manipulated. Findings indicate that subjects did not consume alcohol to cope with the effects of either a prior stressor or an upcoming stressor. These results suggest the need for further refinement of notions concerning women's use of alcohol to cope with stress.     

Site-specific muscle hyper-reactivity in musicians with occupational upper limb pain.

Fourteen musicians who reported a history of pain in the upper limb associated with the playing of their instruments were compared with a sample of pain-free musicians, matched for age, sex and musical instrument. Four tasks were presented in random order and included neutral, general stressor, personal stressor and pain stressor tasks. Ratings of stressfulness and recordings of skin conductance level confirmed the effectiveness of the experimental manipulations for both subject groups. No differences were found between groups or tasks for frontalis surface electromyograph (EMG) activity. Evidence was found, however, of EMG elevation in flexor and trapezius muscles on the pain side for the pain subjects, in response to the task involving recall of a pain experience. This elevation was not found for the pain-free controls or for other stressor tasks, although some elevation in response to the pain stressor task was found for pain subjects in the trapezius muscles of the non-pain side. The duration of return to baseline of EMG following the pain stressor task was found to be extended in pain subjects for the trapezius, but not for the flexor muscles of the pain side. The findings suggest that site-specific muscle hyper-reactivity may play a role in the development and maintenance of occupational upper limb pain in musicians.     

Autonomic responsivity of subjects with body boundary differences during white noise stimulation

A white noise stimulus (85 dB) was used to investigate differences in heart rate (HR) and skin conductance (SC) responsivity of 32 male subjects. The subjects were divided into high and low body boundary (HB and LB) groups, according to Fisher's (1970) revised scoring system of Holtzman Inkblot responses. The hypothesis predicting a significantly larger HR response, that is resistant to habituation, for the LB group, was confirmed. The prediction that the HB group would reveal a larger SC amplitude response accompanied by a shorter recovery time, was supported for the latter. The results confirmed the hypothesis, based on behavioral observations, that the HB individual experiences stress less intensely than the LB person. It also points to individual differences as an important variable in evaluating noise as a stressor.     

Negative affect as a predisposing factor for cortisol release after an acute stress--the impact of unpleasant priming

Glucocorticoids have a key role in stress responses. There are, however, substantial differences in cortisol reactivity among individuals. We investigated if affective trait and mood induction influence the reactivity to psychological stress in a group of 63 young adults, male (n=27) and female (n=36), aged ca. 21 years. On the experimental day the participants viewed either a block of pleasant or unpleasant pictures for 5 min to induce positive or negative mood, respectively. Then, they had 5 min to prepare a speech to be delivered in front of a video-camera. Saliva samples were collected to measure cortisol, and questionnaire-based affective scales were used to estimate emotional states and traits. Compared to basal levels, a cortisol response to the acute speech stressor was only seen for those who had first viewed unpleasant pictures and scored above the average on the negative affect scale. There were no sex differences. In conclusion, high negative affect associated with exposure to an unpleasant context increased sensitivity to an acute stressor, and was critical to stimulation of cortisol release by the speech stressor.     

Attentional bias to threat: Roles of trait anxiety, stressful events, and awareness

Attentional biases for threat stimuli were assessed in high and low trait anxious subjects (n = 66) using a probe detection task. To examine the effects of trait anxiety and situational stressors, each subject was tested three times: Under no stress, laboratory-induced stress, and examination-induced stress. To evaluate the role of awareness, half the word stimuli were presented very briefly (14 msec) and masked, and the other half were presented for 500 msec without a mask. Results showed that high trait anxious subjects under exam stress showed an attentional bias towards unmasked threat stimuli compared with low trait subjects. This effect was not found under lab-induced stress, suggesting that the attentional bias for unmasked threat in high trait subjects may be a function of a prolonged stressor, rather than a transient increase in state anxiety. The results from the masked exposure condition were not predicted; high trait anxious subjects shifted attention towards the spatial location of threat words despite lack of awareness of their lexical content, but this bias was only apparent in the no-stress condition. The results are discussed in relation to recent cognitive theories of anxiety.     

Acute predator stress impairs the consolidation and retrieval of hippocampus-dependent memory in male and female rats

We have studied the effects of an acute predator stress experience on spatial learning and memory in adult male and female Sprague-Dawley rats. All rats were trained to learn the location of a hidden escape platform in the radial-arm water maze (RAWM), a hippocampus-dependent spatial memory task. In the control (non-stress) condition, female rats were superior to the males in the accuracy and consistency of their spatial memory performance tested over multiple days of training. In the stress condition, rats were exposed to the cat for 30 min immediately before or after learning, or before the 24-h memory test. Predator stress dramatically increased corticosterone levels in males and females, with females exhibiting greater baseline and stress-evoked responses than males. Despite these sex differences in the overall magnitudes of corticosterone levels, there were significant sex-independent correlations involving basal and stress-evoked corticosterone levels, and memory performance. Most importantly, predator stress impaired short-term memory, as well as processes involved in memory consolidation and retrieval, in male and female rats. Overall, we have found that an intense, ethologically relevant stressor produced a largely equivalent impairment of memory in male and female rats, and sex-independent corticosterone-memory correlations. These findings may provide insight into commonalities in how traumatic stress affects the brain and memory in men and women.     

Gender roles and the categorization of gender-relevant behavior

Biological sex has been assumed to be a basic category that importantly influences perceptions people have of others. However, it has recently been proposed that there are individual differences in this presumed generic propensity to use sex in person perception — that some people have schemas with regard to sex and gender, whereas others do not. Prior attempts to demonstrate these differences have frequently operationalized their variables in such a way that activation of hypothesized elaborate and dense gender schemas (schemas relating to psychological masculinity and femininity) could not be disentangled from activation of very shallow schemas related simply to biological sex or sex stereotypes. This study provides initial support for the conceptual distinction between cognitive processing based on biological sex vs. psychological gender. Independent manipulation of both sex-stereotyped information and less salient, nonstereotyped gender-relevant behavioral cues demonstrated that two levels of cognitive operation seem to be used. All subjects, regardless of gender role, used surface information regarding biological sex to make inferences regarding targets' masculinity and femininity. However, only some subjects made use of gender-related behavioral cues when assessing masculinity and femininity on indirect measures. Masculine males demonstrated their expertise in sex appropriateness in judging a male target who behaved sex appropriately, whereas cross-sex-typed subjects demonstrated expertise in sex inappropriateness in judgments of a male target who behaved sex inappropriately. The results are consistent with self-schema theory predictions regarding individual differences in schematic processing.An earlier report of this research was presented at the annual meeting of the American Psychological Association, New York, 1987, and additionally received Honorable Mention in the 1986 Association of Women in Psychology/APA Division 35 Student Research Competition. This research was supported by university funds to the second author, and was completed while the first author was at the University of California, Berkeley. The authors would like to thank Lauren Heim, Brad Elman, and Rosa Shen for their assistance with data collection and coding, and Sheri Matteo and two anonymous reviewers for their helpful comments on an earlier draft of this paper.     

Probability learning and coping in dysphoria and obsessive-compulsive tendencies

The processing of stress-relevant categorical events and their contributions to subsequent probability judgments were examined among subjects who were psychometrically categorized as dysphoric, obsessive-compulsive, or “control.” stress-relevant symptomatology of depression was considered to be characterized by a deficit of active counterstress coping activity and obsessive-compulsiveness by ritualistic efforts which have little or no direct effect on stress occurrence. Subjects were presented with a sequence of stressful (loud white noise) and benign (illumination of a green light) events in association with a series of discrete stimuli (alphabetic letters) in three conditions of counterstress activity. Results generally supported the predicted tendency to learn probability information primarily in conditions which reflected the subjects' characteristic ways of responding to stress. Obsessive-compulsives acquired the information primarily in a “ritualistic” context, controls in an active coping context, and dysphorics in both a coping deficit context and unexpectedly in an active coping context. The role of enhanced stressor predicability in maintaining typical stress response patterns of the three groups was discussed.     

Glucocorticoid release and memory consolidation in men and women

Glucocorticoid hormones have been shown to enhance memory consolidation when applied at low doses posttraining, but are ineffective or impair memory at high doses. In a test of whether this quadratic relationship also exists for endogenously released glucocorticoids, healthy men and women received cold-pressor stress (CPS) or a control procedure immediately after reading a relatively neutral story and were tested for retention 1 week later. Cortisol levels in response to the stressor were assayed from saliva. CPS significantly elevated salivary cortisol in both sexes, but enhanced memory only in male subjects. Among CPS-treated male subjects, there was a significant quadratic correlation between cortisol release posttraining and subsequent memory. Thus, these findings represent the first demonstration of an inverted-U relationship between activity of endogenous stress hormones and human memory.     

Effect of cognitive appraisal on d' and response bias to experimental stress.

The effects of an intellectualization-denial passage designed to modify cognitive appraisal of stressor stimuli (gory scences) were evaluated in terms of sensory-decision theory analysis. The passage was found to reduce "felt stress" ') for certain pairs of the stimuli addressed by the passage content but to less effective in reducing stress (Lx) was reduced rather than increased wi;h presentation of the passage for the included simuli only. Differences in d' between subjects classified within treatment groups as repressors versus sensitizers were obtained for certain stimulus pairs generally in the direction of lower sensitivity for repressors. Results are discussed in terms of the effects of altered cognitive appraisal on the "prevention of stress" and on "defensive"denial.     

Chronically stressed female rats show increased anxiety but no behavioral alterations in object recognition or placement memory: a preliminary examination

Stress, depending on intensity and duration, elicits adaptive or maladaptive physiological effects. Increasing evidence shows those patterns of advantageous versus deleterious physiologic stress effects also exist for some brain functions, including learning and memory. For example, short stress enhances, while chronic stress impairs, performance on numerous cognitive tasks in male rats. In contrast, performance of female rats is enhanced, or not altered, following both short-term and long-term stress exposure on the same behavioral tasks. The current study was designed to better characterize the behavioral effects of sustained chronic restraint stress in female rats. Female Sprague Dawley rats were assigned to a stress (restraint, 6 h/day, 35 days) or control (no stress) condition, weighed weekly, and then tested on open field (OF), object recognition (OR) and object placement (OP) tasks. Stressed females gained less weight during stress than controls. On the OF, there were no group differences in locomotor activity, but stressed females made fewer inner visits than controls, indicating increased anxiety. Both groups successfully performed the OP and OR tasks across all inter-trial delays, indicating intact non-spatial and spatial memory in both control and stress females. The current results provide preliminary evidence that the commonly used chronic restraint stress model may not be an efficient stressor to female rats.     

Cognition and mood in relation to the performance of squash tasks

The purpose of this investigation was to determine the role of cognition and mood in the performance of squash tasks, with particular reference to attention and self-reported arousal and stress. Volunteer male subjects (n = 40), divided into three ability groups, 'skilled', 'average' and 'novice', were required to perform two squash tasks with different degrees of difficulty. Order of presentation of the tasks was controlled. Results indicated that subjects completing the easier squash task first performed better on the subsequent difficult task than those subjects who completed the more difficult task first. No differences in scores across tasks were found for subjects completing the tasks in reverse order. Performance was related to level of skill. Furthermore, significant differences in attentional style were revealed when average subjects were compared with skilled and novice players. Skilled players were also found to exhibit significantly different personality characteristics from novice players. Specifically, skilled players exhibited higher levels of extraversion and appeared less neurotic. For the average and novice groups, reports of high levels of stress accompanied those of high levels of arousal and these remained constant throughout the experiment. By contrast, for the skilled group low levels of stress accompanied high levels of arousal. The results are discussed in terms of the effects of these cognitive and mood factors on performance and a suggested direction for future research is offered.