Cardiovascular response of young and older males to mental challenge

Applying psychophysiological coherence training based on HRV-biofeedback to enhance pilots’ resilience and wellbeing

Introduction. The COVID-19 pandemic not only limited pilots’ proficiency in performing routine tasks, but also increased stress levels and operational risk due to new procedures in flight operations related to safety and health regulations. There is, therefore, an increasing need to improve pilots’ mental and physical health to maintain aviation safety

Research question. (1) Does the practice of psychophysiological coherence using heart rate variability (HRV) biofeedback and the Quick Coherence Technique (QCT) improve pilots’ resilience? (2) What effects does psychophysiological coherence practice have on pilots’ resilience and wellbeing?

Method. Eighteen commercial pilots’ perceived stress and wellness were evaluated subjectively by the Perceived Stress Scale (PSS) and Ardell Wellness Self-Assessment (AWSA). They were taught the QCT for facilitating psychophysiological coherence, and their HRV data reflecting automatic nervous system (ANS) activities were collected as they practiced QCT via Inner Balance HRV sensors.

Results. The QCT training improved pilots’ AWSA scores (t = -3.55, p = .002) and decreased PSS scores (t = 6.37, p < .001). Pilots’ post-training HRV were improved with SDNNs higher than pre-training, t = -4.88, p < .001; normalized low frequency (LF) power increased (t = -10.91, p < .001) and low-frequency to high-frequency (LF/HF) ratios increased (t = -3.92, p = .001). Additionally, pilots’ post-training respiration rates were lower than pre-training, t = -2,45, p = .025.

Discussion. Based on the empirical data analysis, HRV-biofeedback QCT can improve psychophysiological coherence and thereby increase pilots’ resilience and wellbeing. Increased post-training SDNNs, normalized LF power, and LF/HF ratio indicate the improvement of ANS control and balance, and stress management capacity. These findings demonstrate the effectiveness of HRV-biofeedback QCT training in improving psychophysiological coherence, which confers real-time and post-practice benefits of optimal energy utility and self-regulation in challenging situations on flight operations and everyday life.

Conclusion. This research demonstrates significant benefits of a short session of HRV-biofeedback QCT on pilots’ resilience and cognitive process by improving psychophysiological coherence. HRV-biofeedback QCT training can be an effective intervention for aviation authorities and airline operators to develop peer support programs for pilots to increase psychological resilience and wellbeing. This may be particularly beneficial given the various challenges presented to pilots in their preparation for return to normal operations.

Age-Related Differences in Cardiac Autonomic Control at Resting State and in Response to Mental Stress

Our goal was to investigate age-related differences in cardiac autonomic control by means of heart rate variability (HRV). For this purpose, 30 healthy older and 34 younger adults were studied during three different conditions: (i) during resting state, (ii) during the execution of two cognitive tasks, and (iii) during the subsequent recovery phase. Mean heart rate and HRV parameters were higher in younger compared to older participants during all three conditions. While the mean heart rate was higher in older adults during the cognitive tasks compared to the resting state, it did not change in younger adults. In contrast, the change in HRV during the three conditions did not differ between age groups. Our results suggest decreased parasympathetic activity reflecting declined cardiac autonomic control with aging. In conclusion, HRV analysis could support the assessment of normal age-related alterations in cardiac autonomic control at resting state and in response to cognitive demands.

Does stress influence the performance of cardiopulmonary resuscitation? A narrative review of the literature

Cardiopulmonary resuscitation represents a major physical and psychological challenge for all involved health care workers because survival of the patients is closely related to the timely and accurate actions of rescuers. Consequently, rescuers may experience high levels of acute mental stress. Stress, in turn, may influence attentional resources and distractibility, which may affect the quality of resuscitation. This narrative review summarizes the current state of research concerning the influence of stress on resuscitation performance. Peer-reviewed studies retrieved in scientific databases were eligible. We found that rescuers experience high levels of stress and some associations of higher levels of stress with lower resuscitation performance. Finally, few interventional studies assessed whether interventions aiming at reducing levels of stress may have a beneficial effect on resuscitation performance, but results are variable. Although the mechanisms linking stress to performance of emergency teams are still not fully understood, factors such as individual experience and self-confidence of rescuers, gender composition and hierarchy within resuscitation teams may play an important role. This review provides a targeted overview of how stress can be defined and measured, how it may influence emergency situations such as a cardiopulmonary resuscitation, and which interventions have the potential to reduce overwhelming stress.

Meta-analysis of the effectiveness of the Trier Social Stress Test in eliciting physiological stress responses in children and adolescents

The Trier Social Stress Test (TSST) is known to reliably induce physiological stress responses in adult samples. Less is known about its effectiveness to elicit these responses in youth samples. We performed a meta-analysis of stress responses to the TSST in youth participants. Fifty-seven studies were included representing 5026 youth participants. Results indicated that the TSST was effective at eliciting stress responses for salivary cortisol (sCort; effect size [ES] = 0.47, p = 0.006), heart rate (HR; ES = 0.89, p < 0.001), pre-ejection period (PEP; ES = -0.37, p < 0.001), heart rate variability (HRV; ES = -0.33, p = 0.028), and systolic blood pressure (ES = 1.17, p < 0.001), as well as negative affect (ES = 0.57, p = 0.004) and subjective anxiety (ES = 0.80, p = 0.004) in youth samples. Cardiac output (ES = 0.15, p = 0.164), respiratory sinus arrhythmia (ES = -0.10, p = 0.064), and diastolic blood pressure (ES = 2.36, p = 0.072) did not reach statistical significance. Overall, effect sizes for the TSST varied based on the physiological marker used. In addition, several physiological markers demonstrated variance in reactivity by youth age (sCort, HR, HRV, and PEP), gender (sCort), type of sample (i.e., clinical versus community sample; sCort and HR), duration of TSST (sCort, HR, HRV, negative affect, and subjective anxiety), number of judges present in TSST (HR and subjective anxiety), gender of judges (sCort), and time of day the marker was assessed (morning versus afternoon/evening; sCort). Overall, the findings provide support for the validity of the TSST as a psychosocial stressor for inducing physiological and psychological stress responses in children and adolescents, but also highlight that some markers may capture the stress response more effectively than others.

Glutamate Within the Marmoset Anterior Hippocampus Interacts with Area 25 to Regulate the Behavioral and Cardiovascular Correlates of High-Trait Anxiety

High-trait anxiety is a risk factor for the development of affective disorders and has been associated with decreased cardiovascular and behavioral responsivity to acute stressors in humans that may increase the risk of developing cardiovascular disease. Although human neuroimaging studies of high-trait anxiety reveals dysregulation in primate cingulate areas 25 and 32 and the anterior hippocampus (aHipp) and rodent studies reveal the importance of aHipp glutamatergic hypofunction, the causal involvement of aHipp glutamate and its interaction with these areas in the primate brain is unknown. Accordingly, we correlated marmoset trait anxiety scores to their postmortem aHipp glutamate levels and showed that low glutamate in the right aHipp is associated with high-trait anxiety in marmosets. Moreover, pharmacologically increasing aHipp glutamate reduced anxiety levels in highly anxious marmosets in two uncertainty-based tests of anxiety: exposure to a human intruder with uncertain intent and unpredictable loud noise. In the human intruder test, increasing aHipp glutamate decreased anxiety by increasing approach to the intruder. In the unpredictable threat test, animals showed blunted behavioral and cardiovascular responsivity after control infusions, which was normalized by increasing aHipp glutamate. However, this aHipp-mediated anxiolytic effect was blocked by simultaneous pharmacological inactivation of area 25, but not area 32, areas which when inactivated independently reduced and had no effect on anxiety, respectively. These findings provide causal evidence in male and female primates that aHipp glutamatergic hypofunction and its regulation by area 25 contribute to the behavioral and cardiovascular symptoms of endogenous high-trait anxiety.SIGNIFICANCE STATEMENT High-trait anxiety predisposes sufferers to the development of anxiety and depression. Although neuroimaging of these disorders and rodent modeling implicate dysregulation in hippocampal glutamate and the subgenual/perigenual cingulate cortices (areas 25/32), the causal involvement of these structures in endogenous high-trait anxiety and their interaction are unknown. Here, we demonstrate that increased trait anxiety in marmoset monkeys correlates with reduced hippocampal glutamate and that increasing hippocampal glutamate release in high-trait-anxious monkeys normalizes the aberrant behavioral and cardiovascular responsivity to potential threats. This normalization was blocked by simultaneous inactivation of area 25, but not area 32. These findings provide casual evidence in primates that hippocampal glutamatergic hypofunction regulates endogenous high-trait anxiety and the hippocampal-area 25 circuit is a potential therapeutic target.

Physiology learning for veterinary students: impact of guided practices on students' opinion and physiological parameters

Over recent decades, education has increasingly focused on student-centered learning. Guided practices represent a new way of learning for undergraduate students of physiology, whereby the students turn into teacher-students and become more deeply involved in the subject by preparing and teaching a practical (laboratory) class to their peers. The goal was to assess the students' opinions about guided practices and how physiological parameters change during the activity. For this objective, two experiments were performed. First, a voluntary questionnaire on guided practices was completed by the students during 2 academic years. Students could also write a free text commentary. The positive answers obtained in the questionnaire and the free commentary responses point to the effectiveness of this methodology in students' minds. Negative aspects included the time spent preparing the activity, and the stress that students experienced in the teaching role. Second, information about how the teacher-students felt before teaching the practical class was self-reported, and physiological parameters related to stress (heart rate, pulse rate, blood pressure, arterial oxygen saturation, respiratory rate, and electrocardiogram recorded to evaluate R-R interval and heart rate variability) were measured immediately before and while the practical class was taught. This evaluation reported an increase in stress during the execution of the practice. In conclusion, despite a new and stressful situation, guided practices are of interest for the students as a learning tool and for the acquisition of skills that may be of use in their later professional lives.

Assessment of Adult Age differences in Task Engagement: The Utility of Systolic Blood Pressure

The constructs of effort and engagement are central to many theoretical frameworks associated with the study of aging. Age differences in the effort associated with effortful cognitive operations have been hypothesized to account for aging effects in ability, and shifting goals and motivation have been hypothesized to be associated with differential levels of engagement across situations in younger and older adults. Unfortunately, the assessment of effort and engagement-constructs that we view as relatively synonymous-has suffered in the field of aging due to the lack of well-validated measures. We suggest that systolic blood pressure might provide an easy and valid means for examining age differences in mental effort, and present evidence in support of its usage. Existing findings clearly support its potential utility, but further empirical and theoretical work is necessary.

Developmental differences in the effects of alcohol and stress on heart rate variability

Adolescent rats differ in their responses to stress and ethanol from their adult counterparts, although not much is known about the contribution of the autonomic nervous system (ANS) to these differences. This study assessed the impact of stress, ethanol, and their combination on parameters of heart rate variability (HRV) in adolescent and adult male Sprague-Dawley rats. Animals were habituated to the testing box and neck sensors (MouseOX, STARR Life Sciences Corp.) used for recording heart rate (HR). After 8-10min of baseline recording, animals were restrained for 90min or returned home, followed by intraperitoneal injection of 0, 0.5, 1.0, or 1.5g/kg ethanol. The 8-10min test recording occurred 30min post-injection. Ethanol-related decreases in LF (an index of sympathetic activity) were evident under non-stressed conditions in adolescents but only after stress in adults, perhaps in part due to apparent ethanol-induced sympathetic deactivation in adolescents. Parasympathetic tone, indexed by HF, was unaffected by both ethanol and stress in adolescents, while again both the 1.0 and 1.5g/kg ethanol doses decreased HF in adults following stress. Ethanol also decreased low frequency/high frequency tone (LF/HF), an index of sympathovagal balance, only in adolescents, with no decrease evident in adults. Further, stressed adults, and not adolescents, had significantly lower CORT and PROG values than their non-stressed counterparts. Taken together, these results demonstrate notable age differences in the ANS response to ethanol under stressful vs. non-stressful circumstances, reflected by ethanol-mediated autonomic effects that were more pronounced following stressor exposure in adults but under non-stressed conditions in adolescents.

Gum chewing modulates heart rate variability under noise stress

OBJECTIVE

Gum chewing may relieve stress, although this hypothesis has not been proven. Heart-rate variability (HRV) is commonly used to measure stress levels. However, it is not known if gum chewing modulates HRV under acute stress. The aim of this study was to investigate the effects of gum chewing on HRV under acute stress.

MATERIALS AND METHODS

A cross-over study involving 47 non-smoking healthy subjects, aged 22-27 years, was carried out. The subjects received a stress procedure with gum chewing (GS group) and without gum chewing (S group). Additionally, the other 20 subjects were allocated to the gum chewing without stress group (G group). The GS and S groups were exposed to noise for 5 min (75 dBA) as stress. Before and after stress exposure/gum chewing, participants completed the state portion of the State-Trait Anxiety Inventory (STAI-s) and a single Stress Visual Analogue Scale (VAS) measurement. HRV measurement was performed before and during stress/gum chewing for 5 min.

RESULTS

After the stress procedure, VAS score significantly increased in the GS and S groups. During the stress procedure, the GS group showed a significantly lower level of high frequency (HF) and higher levels of low frequency (LF) and LF/HF than the S group. However, there were no significant differences in the scores of the state portion of the State-Trait Anxiety Inventory (STAI-s) and VAS between the two stress groups.

CONCLUSIONS

These findings suggest that gum chewing modulates HRV, but may not relieve acute stress caused by noise.

Dynamics and association of different acute stress markers with performance during a simulated resuscitation

AIM

Whether mental stress negatively impacts team performance during cardio-pulmonary resuscitation (CPR) remains controversial; this may partly be explained by differences in stress measures used in previous studies. Our aim was to compare self-reported, biochemical and physiological stress measures in regard to CPR performance.

METHODS

This prospective, observational study was conducted at the simulator center of the University Hospital Basel, Switzerland. Self-reported (feeling stressed and overwhelmed [stress/overload]), biochemical (plasma cortisol) and physiological (heart rate, heart rate variability) stress measures were assessed in 28 residents (teams of 2) before, during and after resuscitation. Team performance was defined as time to start CPR and hands-on time during the first 180 s.

RESULTS

At baseline, significant negative correlations of heart rate variability with stress/overload and heart rate, as well as positive correlations of heart rate and cortisol were found. During resuscitation, self-reported, biochemical and physiological stress measures did not correlate significantly. There was no association of baseline stress measures with performance. During CPR, stress/overload was significantly associated with time to start CPR (regression coefficient 12.01 (95% CI 0.65, 23.36), p=0.04), while heart rate was negatively associated with time to start CPR (regression coefficient -0.78 (95% CI -1.44, -0.11), p=0.027) and positively with hands-on time (regression coefficient 2.22 (95% CI 0.53, 3.92), p=0.015).

CONCLUSIONS

Self-reported stress (stress/overload) was the only predictor for low CPR performance. Biochemical measures showed no association, and physiological measures (heart rate) showed an inverse association, which may be due to physical activity, limiting its value as a mental stress marker in this acute setting.

Relationship between malocclusion and heart rate variability indices in young adults: a pilot study

OBJECTIVES

Heart rate variability (HRV) has been used to assess sympathetic and parasympathetic modulation of heart rate. Chronic stress relates to reduced HRV. Malocclusion has effects on quality of life, which can lead to chronic stress. Therefore, we hypothesized that malocclusion, as chronic stress, may contribute to reduced HRV. The aim of this study was to investigate the relationship between malocclusion and HRV indices in healthy young adults.

METHODS

Thirty-seven non-smoking healthy subjects, aged 22 to 25 years, were examined. Malocclusion was defined by Angle classification. HRV indices included root mean square of successive differences, low frequency (LF), high frequency (HF) and ratio of LF to HF. The effects of malocclusion on quality of life and mental health were assessed using self-reported questionnaires, the condition-specific Oral Impacts on Daily Performances index (CS-OIDP) and the Hopkins Symptoms Checklist (HSCL), respectively.

RESULTS

Significantly lower score of HF and higher heart rate (HR) level and CS-OIDP score were observed in subjects with malocclusion (n = 17) compared to those in the control subjects (n = 20) ( P <0.05). There was a positive correlation between HR and score of "anxiety" in HSCL ( P <0.05).

CONCLUSIONS

The data showed an association between malocclusion and lower HRV. Based on our results, orthodontic treatment might contribute not only to improvement of oral esthetic and functional problems but also to improvement of stress and HRV indices.

Are older adults less or more physiologically reactive? A meta-analysis of age-related differences in cardiovascular reactivity to laboratory tasks

In this meta-analytic review of 31 laboratory studies, we examined if relatively older adults showed lower or higher cardiovascular reactivity compared with relatively younger adults. Results revealed that age was associated with lower heart rate reactivity but higher systolic blood pressure (SBP) reactivity during emotionally evocative tasks. Consistent with the predictions of dynamic integration theory, the result for SBP was moderated by the degree of task activation. These data are discussed in light of existing self-regulatory models and important future research directions.

Heart rate recovery predicts memory performance in older adults

The current study examined cardiovascular reactivity and recovery during memory testing in a sample of 28 younger and 28 older adults. Heart rate (HR) levels were measured before, during, and after a memory test (word list recall). Contrary to prediction, older adults did not have a blunted cardiovascular response to memory tasks compared to younger adults. Word list recall performance was predicted by both Age and an Age x HR recovery interaction. As expected, younger adults performed better on the word list task than older adults. In addition, older adults with better posttest HR recovery performed significantly better than older adults with poor posttest HR recovery, whereas HR recovery differences in younger adults were inconsequential. These relationships were not affected by subjective appraisals of anxiety and task difficulty. Overall, cardiac dysregulation, seen here as low HR recovery, represents an important, potentially modifiable, factor in memory performance in older adults. In addition to being beneficial to overall health, interventions designed to help older adults regulate their HR responses may help offset certain memory declines.

Effects of stress on heart rate complexity--a comparison between short-term and chronic stress

This study examined chronic and short-term stress effects on heart rate variability (HRV), comparing time, frequency and phase domain (complexity) measures in 50 healthy adults. The hassles frequency subscale of the combined hassles and uplifts scale (CHUS) was used to measure chronic stress. Short-term stressor reactivity was assessed with a speech task. HRV measures were determined via surface electrocardiogram (ECG). Because respiration rate decreased during the speech task (p<.001), this study assessed the influence of respiration rate changes on the effects of interest. A series of repeated-measures analyses of covariance (ANCOVA) with Bonferroni adjustment revealed that short-term stress decreased HR D2 (calculated via the pointwise correlation dimension PD2) (p<.001), but increased HR mean (p<.001), standard deviation of R-R (SDRR) intervals (p<.001), low (LF) (p<.001) and high frequency band power (HF) (p=.009). Respiratory sinus arrhythmia (RSA) and LF/HF ratio did not change under short-term stress. Partial correlation adjusting for respiration rate showed that HR D2 was associated with chronic stress (r=-.35, p=.019). Differential effects of chronic and short-term stress were observed on several HRV measures. HR D2 decreased under both stress conditions reflecting lowered functionality of the cardiac pacemaker. The results confirm the importance of complexity metrics in modern stress research on HRV.

Incidence of cardiac events in hypertensive men related to adaptive behavior in stressful encounters

The Serial Color Word Test was administered at baseline to 253 hypertensive men participating in the prospective cohort study of cardiovascular diseases "Men born in 1914" in Malmö, Sweden. This test of psychological adaptation to a stressful encounter was used to investigate whether susceptibility to stress moderates the risk of a cardiac event in association with hypertension. Adaptive behavior, as measured by test performance, can be categorized in two dimensions. The regression dimension refers to linear change of time spent in the test session whereas the variability dimension refers to nonlinear change. Both dimensions consist of four different patterns. At follow-up (mean time = 8.2 +/- 3.5 years), the risk of a cardiac event varied between men with different adaptive patterns. One pattern, the Cumulative-Dissociative pattern of the variability dimension, characterized by a discontinuous and fluctuating time-consumption, was associated to an almost three-fold risk of a cardiac event during follow-up (relative risk [RR], 2.99; 95% confidence interval [CI], 1.33 - 6.70, p = .010) after adjustment for medical-, socioeconomic-, and lifestyle-related factors. No association existed between adaptive patterns and overall mortality.

Aging and cardiovascular reactivity to stress: longitudinal evidence for changes in stress reactivity

Although age differences in cardiovascular function are well documented, little research has provided longitudinal evidence for age-related changes in cardiovascular reactivity to stress. In this study, the authors report such data from a follow-up of their prior work (B. N. Uchino, D. Uno, J. Holt-Lunstad, & J. B. Flinders, 1999) with participants between the ages of 30 to 70 (n=108, mean follow-up=10 months, range=7 to 16 months). Results revealed longitudinal evidence for an age-related increase in systolic blood-pressure reactivity and parasympathetic withdrawal to acute stress. The implications of these findings are discussed in light of the increased cardiovascular disease risk with age, as well as the links between aging, emotions, and physiology.

Differential heart rate reactivity and recovery after psychosocial stress (TSST) in healthy children, younger adults, and elderly adults: The impact of age and gender

In addition to numerous reports about psychophysiological stress responses to acute stressors, there are few data available on gender differences of stress-induced heart rate responses in multiple age groups applying the same psychological stressor. Second, the assessment of poststress recovery appears to be neglected in the empirical literature. For this study, data from 5 independent studies were reanalyzed to investigate the impact of age and gender on heart rate responses and poststress recovery to a standardized psychosocial stress task (Trier Social Stress Test; TSST) in 28 children, 34 younger adults, and 26 older adults. As expected, prestressor baselines correlated significantly with chronological age (r = -.27, p =.01). There was a marked age-related decrease in the heart rate stress response (p =.0003) with children and younger adults showing significantly higher increases than elderly persons. The analysis of gender effects showed that girls had higher heart rate increases during the stress exposure than boys (p =.03). In younger adults, stress responsivity was also higher in women (p =.03). Peak heart rate responses were comparable in older men and women, with only men returning to prestressor baselines during the observation period. In sum, this reanalysis revealed differential heart rate responses and recovery after exposition to the TSST in healthy children, younger adults, and elderly adults.

Cardiovascular response of trained preadolescent boys to mental challenge

PURPOSE

To compare the cardiovascular reactivity response to mental challenge of aerobically trained and untrained preadolescent boys.

METHODS

Heart rate (HR) and blood pressure, as well as stroke volume, total peripheral resistance, rate pressure product, and cardiac contractility response in 15 aerobically trained (10.3 yr) and 15 untrained (9.5 yr) subjects during and recovering from the Stroop task and a computer game (Tetris) were examined. Cardiac vagal activity was also assessed using time series analysis of heart period variability (HPV(ts)).

RESULTS

Untrained compared with trained subjects made significantly more errors during Stroop, whereas performance on Tetris was similar. Trained subjects had significantly lower (P < 0.05) HR and significantly greater cardiac vagal activity at rest. Both groups had significant increases in HR, peripheral resistance, systolic and diastolic blood pressures, rate pressure product, and a significant decrease in vagal activity during Stroop. In contrast, only diastolic blood pressure increased and vagal activity decreased during Tetris. Cardiac contractility of both groups failed to increase during either stressor. Trained compared with untrained subjects had significantly lower absolute HR during and recovering from Stroop. Also HR and vagal activity change, relative to baseline, was significantly greater for the trained during Stroop. During and recovering from Tetris, absolute HR was significantly less for the trained subjects, but change scores were not significantly different.

CONCLUSIONS

The greater HR and vagal activity change of trained subjects to the Stroop suggests greater cardiac reactivity to mental challenge.

Psychophysiological arousal in older adults: a critical review

In spite of the relatively high prevalence rates of anxiety disorders (AD) and related symptoms, very little is known about the experience, presentation, and assessment of anxiety in later life. Because the physiology of the autonomic nervous system changes with age, an enhanced understanding of how these developmental changes affect the somatic-physiological response patterns to anxiety-evoking stimuli among older adults may help explain whether we can generalize current assessment and treatment practices and procedures for AD from younger to older adults. In this paper, we describe and critically evaluate studies that have employed psychophysiological recording of autonomic arousal to anxiety-arousing or stressful stimuli among samples of younger and older adults. The conclusions one can draw from the review are quite limited by both the paucity of relevant literature and the methodological limitations of the published studies.

Effects of short-term psychological stress on the time and frequency domains of heart-rate variability

The purpose of this study was to test the hypothesis that short-term psychological stress produces significant changes in sympathovagal activity. A simple, noninvasive method was used measuring the timing and frequency of heart-rate variability (HRV). 30 normal healthy subjects were assigned into two age- and sex matched groups. In the experimental condition a 5-min. psychological stress test, predominantly based on the Stroop Word Color Conflict Test, was employed in a competitive setting and included a financial inducement to produce psychological strain. Analysis showed that during psychological stress a significant reduction in the timing and frequency of heart rate variability was observed. The standard deviation of interbeat intervals decreased. A significant increase in heart rate was also observed. Within the frequency domain, a significant reduction in the high frequency component of HRV and a significant increase in the low frequency component were observed. There was also a significant increase in the low frequency to high frequency ratio. Self-evaluation of physical tension and emotional state measured by visual analog scales also showed significant increases following psychological stress. No significant differences were observed on any variables within the control group. The results indicate a shift towards sympathetic predominance as a result of parasympathetic withdrawal and demonstrates that this psychological stress test is effective in provoking a characteristic defence-arousal reaction. This simple, cost-effective method of analysing heart rate variability is suitable for detection of short-term changes in sympathovagal balance.

Physiological and emotional response to psychological stressors in psychiatric and psychosomatic disorders

Deviations from emotional and physiological homeostasis in humans occur under episodic, chronic, or traumatic stress experiences. These dysregulations can provoke emotional and physical disturbances that may result in stress-related psychiatric or psychosomatic disorders. This brief review discusses a variety of both naturally occurring and experimental stressors and the complexity of intervening variables on cardiovascular and hormonal dysregulations of the hypothalamic-pituitary-adrenal (HPA) axis. In addition to the type, intensity, and duration of the stressor, subject variables such as dispositional factors (e.g., age and sex), personality traits, and coping styles are considered. Finally, emotional and physiological stress responses to naturally occurring stressors and psychological challenge tests in depressed patients and anxiety disorder patients are presented and discussed. Stressors in humans induce emotional arousal, which leads to physiological activation of the central nervous system, an increase of hormones of the HPA axis, and coping reactions on the psychological and behavioral level. Depending on the type, intensity, and duration of the stressor, on personal and psychosocial resources of the individual, stressful situations may provoke emotional and physical disturbances. These dysfunctions may result in psychosomatic or psychiatric disorders. The following brief review intends to discuss a variety of stressors that have been examined in humans in order to gain insight into the complex relationship between physiological and behavioral stress reactions and the occurrence or maintenance of stress related psychosomatic and psychiatric disorders.