Consistency in physiological stress responses and electromyographic activity during induced stress exposure in women and men

Physiological responses serve the role as objective indicators of stress as well as a link between psychosocial stress and various health outcomes. The aim of the present exposure session was to compare different physiological stress responses (systolic and diastolic blood pressure, heart rate, urinary epinephrine and norepinephrine, salivary cortisol) as well as trapezius muscle activity, measured by surface electromyography, during mental and physical stress in 11 women and ten men. The results show significantly increased activity in all measures but cortisol and significant associations between sympathetic arousal and EMG activity. The association between sympathetic arousal and muscle activity is of importance for understanding the high prevalence of musculoskeletal disorders in mentally stressful but physically light work tasks. Men had higher blood pressure and a more pronounced increase in epinephrine output than women, whereas women had higher heart rate. It was concluded that sympathetic activity is more sensitive to moderately intense stress exposure than pituitary adrenocortical (cortisol) activity and that men respond to performance stress with more epinephrine output than women. Although the correlations between the different indicators of sympathetic arousal were high, together they could still only explain 30–70% of the inter-individual variance. Thus, several parameters are needed in order to obtain a reliable measure of sympathetic activity.     

Individual response differences in spider phobia: comparing phobic and non-phobic women of different reactivity levels

In contrast to previous stress research, studies concerning phobic disorders have never systematically investigated individual response differences between phobic participants integrating numerous different response measures. The aim of this article is to clarify the existence of significant individual response differences in psychophysiological responses (e.g., heart rate, skin conductance responses (SCR), corrugator, cortisol), subjective ratings (e.g., valence, arousal), and avoidance behavior in 46 spider phobic and 44 non-phobic women when exposed to 20 phobic and 20 neutral pictures. Previous studies that did not attend to individual response differences showed that, during phobic stimulation, phobic individuals have increased psychophysiological responses (heart rate, SCR, and corrugator responses), more negative valence rating, and more subjective arousal than non-phobic individuals. These results were confirmed by our data. With regard to individual response uniqueness, 1/3-2/3 of spider-phobic women with low responsiveness in heart rate, cortisol, and avoidance behavior were indistinguishable from non-phobic women during phobic stimulation. With SCR, corrugator EMG, and subjective ratings, no individual response uniqueness was found. Based on the findings, exposure therapy might be improved by tailoring interventions to individuals with a therapeutic focus on those psychophysiological measures that show the highest individual responsivity.     

Cardiovascular and neuroendocrine activity in preschool children: Comparison between day-care and home levels

Thirty boys and 30 girls at nine day-care centers were examined at the mean age of 3.5 and 5.5 with regard to systolic and diastolic blood pressure, heart rate and neuroendocrine activity (urinary catecholamines and cortisol) during a day at their day-care center and in their home, respectively. Compared to home levels, day-care was associated with increased heart rate, epinephrine and norepinephrine excretion and decreased cortisol levels. Systolic blood pressure decreased at the day-care centers at the age of 3.5 and increased at the age of 5.5. No significant sex differences were found. The possible role of mental and physical arousal and the dissociation between the sympathetic-adrenal medullary and the pituitary-adrenal cortical responses are discussed.     

Stress impairs acquisition of delay eyeblink conditioning in men and women

In rodents stress impairs delay as well as trace eyelid conditioning in females, but enhances it in males. The present study tested the effects of acute psychosocial stress exposure on classical delay eyeblink conditioning in healthy men and women. In a between subject design, participants were exposed to psychosocial stress using the Trier Social Stress Test (TSST) or a control condition which was followed by a delay eyeblink classical conditioning procedure. Stress exposure led to a significant increase in salivary cortisol and impaired acquisition of conditioned eyeblink responses (CRs). This was evident by a later first CR and an overall lower CR rate of the stress group. The stress-induced acquisition impairment was observed in both women and men. Subjects failing to show a stress-induced cortisol increase (cortisol non-responder) were not impaired in acquisition. Our findings indicate that acute stress, possibly via activation of the hypothalamus–pituitary–adrenal (HPA) axis, reduces the ability to acquire a simple conditioned motor response in humans.     

Individual response differences in spider phobia: Comparing phobic and non-phobic women of different reactivity levels

Abstract

In contrast to previous stress research, studies concerning phobic disorders have never systematically investigated individual response differences between phobic participants integrating numerous different response measures. The aim of this article is to clarify the existence of significant individual response differences in psychophysiological responses (e.g., heart rate, skin conductance responses (SCR), corrugator, cortisol), subjective ratings (e.g., valence, arousal), and avoidance behavior in 46 spider phobic and 44 non-phobic women when exposed to 20 phobic and 20 neutral pictures. Previous studies that did not attend to individual response differences showed that, during phobic stimulation, phobic individuals have increased psychophysiological responses (heart rate, SCR, and corrugator responses), more negative valence rating, and more subjective arousal than non-phobic individuals. These results were confirmed by our data. With regard to individual response uniqueness, 1/3–2/3 of spider-phobic women with low responsiveness in heart rate, cortisol, and avoidance behavior were indistinguishable from non-phobic women during phobic stimulation. With SCR, corrugator EMG, and subjective ratings, no individual response uniqueness was found. Based on the findings, exposure therapy might be improved by tailoring interventions to individuals with a therapeutic focus on those psychophysiological measures that show the highest individual responsivity.     

Lipid reactivity to stress: II. Biological and behavioral influences.

This study examined behavioral and physiological influences on lipid concentrations during acute and chronic stressors. One hundred men (n = 92) and women (n = 8) were tested during a chronic stressor and during 2 acute stressors. During chronic stress, diet, physical activity, exercise, and sleep were examined. During the acute stressors, catecholamines, cortisol, plasma volume, and cardiovascular responses were examined. None of the behavioral influences could explain the lipid response to chronic stress. Responses of the atherogenic lipids to acute stressors were not solely reflecting hemoconcentration of the plasma but were moderately correlated with cardiovascular, epinephrine, and cortisol reactivity. Diastolic blood pressure reactors to the acute stressors had larger lipid responses to the chronic stressor than did nonreactors. Elevations in blood lipids during stress are not artifacts and may be clinically significant.     

Gender differences in cardiovascular and hypothalamic-pituitary-adrenal axis responses to psychological stress in healthy older adult men and women

Gender differences in the neuroendocrine and cardiovascular response to psychological stress may contribute to the gender differences in the prevalence of diseases associated with hypothalamic-pituitary-adrenal (HPA) axis reactivity such as cardiovascular disease (CVD), diabetes and hypertension. We measured plasma ACTH, cortisol, heart rate (HR), and blood pressure (BP) responses in 8 men and 8 women (55-75 years) exposed to the Matt Stress Reactivity Protocol (MSRP), a psychological challenge. The MSRP elicited significant increases in HR, systolic-, and diastolic BP, ACTH and cortisol (all p<0.01). Men had significantly greater cortisol and diastolic BP responses compared to women (p<0.05). Additionally, a positive correlation between the ACTH and cortisol responses was only found in the males (r=0.71, p<0.05). There were no group differences in HR, systolic BP, or ACTH responses. We conclude, that among older adults, men respond to psychological stress with greater increases in cortisol, compared to women. This greater activation of the HPA axis could translate into an elevated risk for CVD, diabetes and hypertension and may be related to the higher prevalence of these diseases in males. Gender differences in brain structures and/or cognitive processes may be responsible for these sexually dimorphic stress responses.     

Chronic stress influences cardiovascular and neuroendocrine responses during acute stress and recovery, especially in men.

This study tests the influence of chronic stress on cardiovascular and neuroendocrine responses to and recovery from acute stressors and whether the effects are gender specific. Sixty-two healthy, middle-aged persons (50% women) performed mental-arithmetic and public-speaking tasks and relaxed thereafter for 1 hr while their cardiovascular and neuroendocrine function was measured. Participants with higher levels of chronic stress showed lower systolic blood pressure (SBP) and epinephrine (E; men only) and marginally lower levels of norepinephrine (NE) responses to the tasks and showed lower levels of cortisol and marginally lower NE responses during recovery. Relative to women, men had high diastolic blood pressure (DBP) responses to the tasks and high SBP, DBP, and E responses during recovery. Gender differences in cardiovascular disease in midlife may be due to gender differences in the inability to recover quickly, in addition to enhanced acute-stress response.     

Effects of pre-learning stress on memory for neutral, positive and negative words: Different roles of cortisol and autonomic arousal

Stress can have enhancing or impairing effects on memory. Here, we addressed the effect of pre-learning stress on subsequent memory and asked whether neutral and emotionally valent information are differentially affected by specific stress components, autonomic arousal and stress-induced cortisol. Ninety-six healthy men and women underwent either a stressor (modified cold pressor test) or a control warm water exposure. During stress, participants showed comparable autonomic arousal (heart rate, blood pressure), while 60 percent showed an increase of cortisol (responders vs. 40 percent non-responders). Ten minutes after the cold pressor test neutral, positive and negative words were presented. Free recall was tested 1 and 24 h later. Overall, positive and negative words were better recalled than neutral words. Stress enhanced the recall of neutral words independently of cortisol response. In contrast, the free recall of negative words was enhanced in cortisol responders in the 1-h but not 24-h test which might suggest different effects of cortisol on consolidation and reconsolidation processes. Recall for positive words was unaffected by stress-induced cortisol. To summarize, (i) pre-learning stress can enhance memory for neutral words independently of cortisol and (ii) stress effects on memory for negative words appear to rely on stress-induced cortisol elevations, the absence of this effect for positive words might be at least partly due to differences in arousal evoked by positive vs. negative words.     

Stress reactivity and exercise training in premenopausal and postmenopausal women.

Examined the influence of ovarian function on psychophysiological stress responses and determined if aerobic exercise reduced stress reactivity. Fifty premenopausal and postmenopausal women initially were subjected to a public speaking task and an ice-on-the-forehead procedure, during which time their blood pressure and heart rate were monitored and continuous blood samples were obtained. Subjects also underwent aerobic fitness evaluations with a maximum-exercise treadmill test. Subjects were then randomly assigned to a 12-week exercise program of either aerobic exercise (e.g., walking and jogging at a prescribed exercise intensity) or non-aerobic strength and flexibility training and were then reevaluated. Results indicated that postmenopausal women exhibited lower resting epinephrine levels but greater epinephrine reactivity to the speaking task compared to the premenopausal women. There were no differences between premenopausal and postmenopausal women with respect to cardiovascular or catecholamine responses during the cold challenge. Premenopausal and postmenopausal women also achieved comparable improvements in aerobic fitness. However, results of the mental stress testing were complex and provided only partial support for the role of aerobic exercise in reducing stress responses.     

Gender Differences in Biobehavioral Aftereffects of Stress on Eating,Frustration, and Cardiovascular Responses1

Eating, persistence, and cardiovascular responses were evaluated after exposure to a 25‐min noise stressor with or without perceived control. Participants were healthy men (n = 29) and women (n = 34), aged 21 to 45 years. There were no group differences in cognitive task performance or blood pressure during the stressor. However, perceived control resulted in lower mean blood pressure and heart rate after cessation of the stressor for men and women. Women without perceived control displayed greater frustration levels following the stressor, and frustrated women ate more bland food than did nonfrustrated women. Perceived control and frustration did not affect food consumption among men following the stressor. These findings indicate that there are health‐relevant gender differences in biobehavioral responses that occur in the aftermath of stressor exposure. In addition, perceived control was especially important for women to attenuate the behavioral and biological effects of stressor exposure.     

Women with diarrhoea-predominant irritable bowel syndrome show an increased pressure response to 35% carbon dioxide stress challenge

The responses to inhalation of 35% carbon dioxide (CO(2)) as a stressor were compared in female irritable bowel syndrome (IBS) patients and healthy controls to assess potential differences in cardiovascular, neuroendocrine and behavioural responses to stress. A total of 22 women (12 patients with ROME II defined diarrhoea-predominant IBS and 10 aged-matched controls) were challenged with a single vital capacity breath of 35% CO(2) (with 65% oxygen). Beat-to-beat blood pressure and heart rate were recorded prior to, during and after the inhalation. Serum cortisol concentration and behavioural ratings were measured pre- and post-inhalation. A typical pattern of responses to CO(2) was observed, characterised by a reduction in heart rate and increases in serum cortisol and anxiogenic symptoms; however, these responses did not differ between groups. Both groups also demonstrated an increase in systolic blood pressure; however, this response was significantly enhanced in IBS patients compared to healthy controls (P < 0.05). These findings demonstrate that females with diarrhoea-predominant IBS have an exaggerated pressor response to 35% CO(2) stress challenge, suggesting a more stress-responsive sympathetic nervous system.     

Enhancing effects of acute psychosocial stress on priming of non-declarative memory in healthy young adults

Social stress affects cognitive processes in general, and memory performance in particular. However, the direction of these effects has not been clearly established, as it depends on several factors. Our aim was to determine the impact of the hypothalamus-pituitary-adrenal (HPA) axis and sympathetic nervous system (SNS) reactivity to psychosocial stress on short-term non-declarative memory and declarative memory performance. Fifty-two young participants (18 men, 34 women) were subjected to the Trier Social Stress Task (TSST) and a control condition in a crossover design. Implicit memory was assessed by a priming test, and explicit memory was assessed by the Rey Auditory Verbal Learning Test (RAVLT). The TSST provoked greater salivary cortisol and salivary alpha-amylase (sAA) responses than the control task. Men had a higher cortisol response to stress than women, but no sex differences were found for sAA release. Stress was associated with an enhancement of priming but did not affect declarative memory. Additionally, the enhancement on the priming test was higher in those whose sAA levels increased more in response to stress (r(48)?=?0.339, p?=?0.018). Our results confirm an effect of acute stress on priming, and that this effect is related to SNS activity. In addition, they suggest a different relationship between stress biomarkers and the different memory systems.     

Stress exposure and affective modulation of aggressive behavior in men and women

To study differences in the effects of stress exposure and affective responding on aggression in men and women, the authors examined the effects of an acute stressor (air blast) on subsequent aggressive behavior, measured as the intensity of shocks men and women delivered to a putative employee. The authors measured participants' affective responding using the startle reflex. Results showed that although men and women did not differ in their startle responses to the actual stressor, high stress led to contrasting patterns of subsequent aggressive behavior. Women under high stress responded with less aggression than women under low stress, whereas men exposed to high stress exhibited increases in aggression relative to those under low stress. Affective responding during the stressor differentially modulated aggression in men and women: Startle responses predicted increasing levels of aggression in men and less aggression in women. These findings suggest that although men and women show similar basic affective processing in response to stressors, the behavioral profiles associated with stress differ in men and women. These findings have implications for understanding gender differences in the prevalence of internalizing and externalizing psychopathology.     

Biological basis of the stress response.

Chronic, as well as acute emotional arousal, is a consequence of various types of social interaction, i.e., those between mother and infant and between controlling dominant and less effective subordinate. The neurohumoral accompaniments of this social stress include the sympathetic adrenal medullary and hypothalamic pituitary adrenal responses. A common ensuing pathophysiological state involves a chronic increase of blood pressure. Although Selye's General Adaptation Syndrome presupposed the same response to a variety of stimuli; recent work shows that specific perceptions of control result in different patterns of neuroendocrine activation. A challenge perceived as easy to handle will elicit an active coping response and release of the neurosympathetic system's norepinephrine. Testosterone will rise as the subject savors success. With increasing anxiety this active coping shifts to a more passive mode and the behavior becomes less assured as the animal loses control. The norepinephrine/epinephrine ratio decreases as epinephrine, prolactin, renin and fatty acids rise. As the outcome becomes still less certain and distress grows, adrenocorticotropic hormone and cortisol levels arise. Thus, the effort required on the one hand and the degree of frustration conflict and uncertainty on the other, determine the ratio of catecholamines to corticoids. With severe emotional trauma, brain dysfunction may occur. These effects can be lasting, and corticoids paradoxically return to normal as the behavior changes to that of post-traumatic stress disorder. Repression and denial set in and the organism responds with decreased concern of impaired attachment and increased irritability.     

Biological basis of the stress response

Chronic, as well as acute emotional arousal, is a consequence of various types of social interaction, i.e., those between mother and infant and between controlling dominant and less effective subordinate. The neurohumoral accompaniments of this social stress include the sympathetic adrenal medullary and hypothalamic pituitary adrenal responses. A common ensuing pathophysiological state involves a chronic increase of blood pressure. Although Selye’s General Adaptation Syndrome presupposed the same response to a variety of stimuli; recent work shows that specific perceptions of control result in different patterns of neuroendocrine activation. A challenge perceived as easy to handle will elicit an active coping response and release of the neurosympathetic system’s norepinephrine. Testosterone will rise as the subject savors success. With increasing anxiety this active coping shifts to a more passive mode and the behavior becomes less assured as the animal loses control. The norepinephrine/epinephrine ratio decreases as epinephrine, prolactin, renin and fatty acids rise. As the outcome becomes still less certain and distress grows, adrenocorticotropic hormone and cortisol levels arise. Thus, the effort required on the one hand and the degree of frustration conflict and uncertainty on the other, determine the ratio of catecholamines to corticoids. With severe emotional trauma, brain dysfunction may occur. These effects can be lasting, and corticoids paradoxically return to normal as the behavior changes to that of post-traumatic stress disorder. Repression and denial set in and the organism responds with decreased concern of impaired attachment and increased irritability.     

Impaired memory retrieval correlates with individual differences in cortisol response but not autonomic response

Stress can enhance or impair memory performance. Both cortisol release and sympathetic nervous system responses have been implicated in these differential effects. Here we investigated how memory retrieval might be affected by stress-induced cortisol release, independently of sympathetic nervous system stress responses. Thirty-two healthy participants (16 women) learned emotionally arousing and neutral words. One hour later, half of the participants underwent a stressor (cold pressor test) and the other half, a control warm water exposure, both followed by a delayed free recall task. The stressed participants were split into those who did (responders, N = 8) and those who did not (nonresponders, N = 6) show a cortisol response. Both responders and nonresponders showed comparable sympathetic nervous system activity (skin conductance level) during the cold pressor. The cortisol responders recalled significantly fewer words compared to nonresponders, and compared to control participants; this effect was most pronounced for moderately arousing words (compared to highly arousing and neutral words). These results suggest that individual differences in cortisol reactivity affect memory retrieval performance, and help to explain the differential effects of stress on memory.     

Stress,sex, and satisfaction in marriage

Using data from 198 couples, this study examines whether associations between stress occurring outside of the dyad and key indicators of relationship functioning are mediated by stress arising within the dyad. Findings suggest that relationship satisfaction and sexual activity are governed by hassles and problems experienced within the dyad that are in turn related to stress arising outside the dyad. Associations between external stress and relationship functioning are stronger for daily hassles than for critical life events. Higher levels of daily stress predicted less sexual activity for maritally dissatisfied women and more sexual activity for maritally dissatisfied men. Self‐reports of stress covaried with self‐reported indexes of satisfaction and sexuality, suggesting that contextual influences are broadly influential in intimate relationships.     

Differentiating the impact of episodic and chronic stressors on hypothalamic-pituitary-adrenocortical axis regulation in young women.

OBJECTIVE: The goal of this study was to examine the impact of episodic stress and chronic interpersonal stress on indices of HPA regulation. To explore the potential downstream consequences of altered HPA dynamics, the authors also assessed indicators of metabolic control and systemic inflammation. DESIGN: One hundred four medically healthy women between the ages of 15 and 19 participated. Following an in-depth interview of life stress, a sample of blood was drawn through antecubital venipuncture. Over the course of the next 2 days, participants gathered salivary cortisol samples. MAIN OUTCOME MEASURES: Cortisol morning response, cortisol daily output, glucocorticoid receptor (GR) mRNA, C-reactive protein (CRP), insulin, and glucose. RESULTS: The simple presence of episodic stress or chronic interpersonal stress was not reliably associated with cortisol output, GR mRNA, insulin, or glucose. When women were exposed to an episodic stressor in the midst of chronic stress they showed increased cortisol output and reduced expression of GR mRNA. By contrast, when women had low levels of chronic stress, episodic events were associated with decreased cortisol output and increased GR mRNA. Episodic and chronic stress also interacted to predict CRP, but not insulin or glucose. CONCLUSIONS: The impact of episodic stress is accentuated in the midst of chronic interpersonal stress and diminished in its absence. Simultaneous exposure to episodic and chronic stress may create wear and tear on the body, whereas exposure to episodic stress in the context of a supportive environment may toughen the body, protecting it against subsequent stressors.     

Gender Differences in Cardiovascular Reactivity and Game Performance Related to Sensory Modality in Violent Video Game Play1

This study examined the gender‐specific cardiovascular and performance responses to playing the violent video game “DOOM” with and without the soundtrack. Men and women equally rated the game as more violent with the soundtrack. Men performed the game about twice as well with the soundtrack. Women's performance did not change at all. Only men's heart rates were significantly greater with the soundtrack, indicative of arousal. Only women's systolic and diastolic blood pressures were significantly greater with the soundtrack, indicative of stress. The game seemed to appeal more to men than to women. Moreover, women may possibly avoid violent video games, in part because they represent an undesirable stressor.