Correlations between psychological and physiological responses to acute flight phobia stress

Interventions to reduce adult state anxiety, dental trait anxiety, and dental phobia: A systematic review and meta-analyses of randomized controlled trials

This review evaluates randomized controlled trials (RCTs) intervening on adult state anxiety (fear and emotional distress during dental treatment), chronic dental (trait) anxiety or dental phobia (disproportionately high trait anxiety; meeting diagnostic criteria for specific phobia). Seven online databases were systematically searched. 173 RCTs met inclusion criteria, of which 67 qualified for 14 pooled analyses. To alleviate state anxiety during oral surgery, moderate-certainty evidence supports employing hypnosis (SMD=-0.31, 95 %CI[-0.56,-0.05]), and low-certainty evidence supports prescribing benzodiazepines (SMD=-0.43, [-0.74,-0.12]). Evidence for reducing state anxiety is inconclusive regarding psychotherapy, and does not support virtual reality exposure therapy (VRET), virtual reality distraction, music, aromatherapy, video information and acupuncture. To reduce trait anxiety, moderate-certainty evidence supports using Cognitive Behavioral Therapy (CBT; SMD=-0.65, [-1.06, -0.24]). Regarding dental phobia, evidence with low-to-moderate certainty supports employing psychotherapy (SMD=-0.48, [-0.72,-0.24]), and CBT specifically (SMD=-0.43, [-0.68,-0.17]), but not VRET. These results show that dental anxieties are manageable and treatable. Clinicians should ensure that interventions match their purpose-managing acute emotions during treatment, or alleviating chronic anxiety and avoidance tendencies. Existing research gaps underscore the necessity for future trials to minimize bias and follow CONSORT reporting guidelines.

Review of Psychophysiological and Psychotherapeutic Studies of Stress Using Virtual Reality Technologies

This review addresses the use of virtual reality technologies in the psychophysiology and psychotherapy of stress. Studies using virtual reality both to introduce subjects into a state of stress and to help reduce stress reactions are reviewed. Methods developed for treating patients suffering from stress-related disorders (in particular, PTSD and phobias) are described. In many cases, reductions in stress reactions with the help of virtual reality systems are achieved not only at the self-report (experiential) level, but also at the level of central and peripheral nervous system measures. This allows virtual reality to be regarded as a modern, inexpensive, and effective method, firstly, for introducing subjects into a state of stress with the aim of testing various hypotheses in psychophysiology and, secondly, to reduce stress reactions.

The Effects of Visual Displays in Attenuating Discrepancies Between Self-Reported and Physiological Indexes of Stress

Abstract. This study examined whether the relationship between subjective and physiological outcomes of stress, and the responsivity to stressors, are affected by whether participants can see a visual display of their physiological output. Participants were randomly assigned to have a visible view of their physiological output readings, or to a condition in which physiological output readings were out of view. Participants individually completed a 30-min laboratory study including the modified Trier Social Stress Task. Both physiological markers of stress (heart rate and blood pressure) and subjective evaluations of stress (visual analog scale) were measured. Results found little congruency across subjective and physiological measures of stress. The visible visual display condition had elevated physiological arousal, while no group differences were observed in self-reported stress. Findings from the study provide insight into the use of visual physiological displays and hold practical implications for both the measurement of stress in research, and the development of wearable technologies without accompanying response strategies.

Synchronous change in subjective and physiological reactivity during flight as an indicator of treatment outcome for aviophobia: A longitudinal study with 3-year follow-up

BACKGROUND AND OBJECTIVES

Emotion can be seen as the organizing process that coordinates response systems to deal effectively with challenges and opportunities. Synchronous change in subjective and physiological reactivity is regarded as an indication of this organizing process. Synchrony is expected to increase with the intensity of emotional stimuli. Conversely, adaptive emotional functioning could be indicated by progressive synchrony upon increasing demands, and the magnitude of synchrony could be an indication of progress during therapy.

METHODS

We examined whether synchronous change in subjective and physiological reactivity over repeated exposures increased from watching a flight video through simulated flight to actual flight, and whether the magnitude of synchronous change predicted favourable short- and long-term treatment outcome within a group of 77 aviophobic participants during CBT.

RESULTS

Results did not show a relationship between the intensity of the phobic stimuli and the magnitude of synchronous change in subjective and physiological reactivity. Moreover, synchronous change across both response systems did not predict treatment outcome.

LIMITATIONS

By design this study had no control group. Additional treatment or life events between end of treatment and 3-year follow-up were not assessed.

CONCLUSION

The results provide only weak support for the functionalistic view that successful treatment of anxiety disorders is indicated by synchronous change in reactivity across emotional response systems. The relationship between these systems is likely to be affected by many intervening variables including higher order cognitive processes.

The efficacy of stress reappraisal interventions on stress responsivity: A meta-analysis and systematic review of existing evidence

BACKGROUND

The beliefs we hold about stress play an important role in coping with stressors. Various theoretical frameworks of stress point to the efficacy of reframing stress-related information through brief reappraisal interventions in order to promote adaptive coping.

PURPOSE

The goal of the current meta-analysis and systematic review is to substantiate the efficacy of reappraisal interventions on stress responsivity compared to control conditions. Differences in experimental methodologies (e.g., type of stressor used, timing of reappraisal intervention, and content of intervention instructions) will be examined to further delineate their effects on intervention outcomes.

METHODS

The literature searches were conducted on May 16, 2018 using PsycINFO, ProQuest Dissertations and Theses, and PILOTS databases with no date restriction. The search terms included stress, reframing, reappraisal, mindset and reconceptualising. A total of 14 articles with 36 independent samples were included in the meta-analysis, while 22 articles with 46 independent samples were included in the systematic review. Random-effects model was used to test the null hypothesis using two-tailed significance testing. Fisher's Z value was reported for each corresponding test. Heterogeneity tests are reported via Cochran's Q-statistics.

RESULTS

Findings from both the meta-analysis and systematic review revealed that overall, reappraisal interventions are effective in attenuating subjective responsivity to stress. Standard differences in means across groups are 0.429 (SE = 0.185, 95% CI = 0.067 to 0.791; z = 2.320, p = .020). However, reappraisal intervention groups did not outperform control groups on measures of physiological stress, with standard differences of -0.084 (SE = 0.135, 95% CI = -0.349 to 0.180; z = -0.627, p = .531). Moderator analysis revealed heterogeneous effects suggesting large variability in findings.

CONCLUSIONS

On one hand, findings may suggest a promising avenue for the effective management of self-reported stress and optimization of stress responses. However, more research is needed to better elucidate the effects, if any, of reappraisal interventions on stress physiology. Implications for the use of reappraisal interventions on stress optimization are discussed in the context of theoretical frameworks and considerations for future studies.

Psychological Distress and Physiological Reactivity During In Vivo Exposure in People With Aviophobia

OBJECTIVES

Exposure is regarded to be a crucial component of therapies for phobias. According to emotional processing theory, the success of exposure therapy is predicted by activation of subjective and physiological fear responses and their within-session habituation and between-session adaptation. This study tested this prediction for aviophobia.

METHODS

Seventy-nine participants following a highly standardized treatment program for aviophobia provided self-reported and physiological (heart rate, respiratory sinus arrhythmia and pre-ejection period) measurements of fear activation, within-session habituation, and between-session adaptation during exposure to flight-related stimuli, a flight simulator, and during two real flights. Multiple regression analyses were conducted to examine whether these measurements predicted therapy outcome up to 3 years after finishing therapy, including number of flights flown in this period.

RESULTS

Both subjective and physiological arousal measurements indicated strong fear activation and large within-session habituation and between-session adaptation during exposure. Flight anxiety measures showed large improvements up to 3 years after treatment (η between 0.72 and 0.91). Lower self-reported anxiety during flight exposure was associated with lower flight anxiety after exposure (R = 0.15) and more flights flown (R = 0.14). Within-flight habituation or between-session adaptation of self-reported anxiety had no relationship with treatment outcome. Within-flight habituation of HR reactivity (R = 0.10) and respiratory sinus arrhythmia reactivity (R = 0.11) was associated with lower flight anxiety directly after the flight, but not on flight anxiety 3 years after finishing therapy or on long-term flying behavior.

CONCLUSIONS

The results provide only weak support for emotional processing theory. Low self-reported anxiety during in vivo flight exposure was the best predictor of successful long-term therapy outcome.

Anxiety sensitivity moderates the relationship of changes in physiological arousal with flight anxiety during in vivo exposure therapy

Physiological sensations and discomfort constitute the major symptoms reported by aviophobics. Anxiety sensitivity (AS) seems to moderate the relationship between self-reported somatic sensations and flight anxiety, and AS has been identified as a vulnerability factor for flight phobia. In this study we examined whether AS moderates the effects of somatic sensations and autonomic nervous system reactivity on flight anxiety induced by real flight. In fifty aviophobics participating in Cognitive Behaviour Group Therapy (CBGT), flight anxiety, somatic sensations and autonomic nervous system reactivity were assessed during a guided return flight. Results indicate that physiological reactivity interacted with AS. Changes in heart rate and parasympathetic activity were more strongly associated with changes in reported flight anxiety for high AS participants, and less for participants low on AS. Results did not indicate a moderating effect of AS on the relationship between self-reported somatic sensations and flight anxiety. Our results suggest that therapy for flight phobia might benefit from addressing the physical effect of anxiety, by means of cognitive restructuring and exposure to interoceptive stimuli, particularly in aviophobics high in AS.

The psychology of fear of flying (part I): a critical evaluation of current perspectives on the nature, prevalence and etiology of fear of flying

Fear of flying, its nature, prevalence, etiology and treatment, has been the subject of a substantial quantity of research over the past 30 years. With the exception of a dated review of treatment methods however, there has been no evaluation of this expanding body of evidence, its contribution to theory and influence on clinical practice. Published research has also generally failed to apply developments in the understanding and treatment of anxiety disorders generally to fear of flying. This review provides a critical evaluation of the existing literature and what it reveals about theory and practice. It does this from the perspective of Cognitive Behavioural Therapy. The evidence reviewed demonstrates that fear of flying is a heterogeneous phenomenon which is acquired under the influence of complex psychological, social and physiological factors unique to each affected individual. Effective psychological interventions must therefore be founded on a comprehensive functional assessment of each individual, a finding which is considered in detail in the second part of this review.

Physiological reactivity to phobic stimuli in people with fear of flying

OBJECTIVE

The nature of the relationship between physiological and subjective responses in phobic subjects remains unclear. Phobics have been thought to be characterized by a heightened physiological response (physiological perspective) or by a heightened perception of a normal physiological response (psychological perspective).

METHOD

In this study, we examined subjective measures of anxiety, heart rate (HR), and cardiac autonomic responses to flight-related stimuli in 127 people who applied for fear-of-flying therapy at a specialized treatment center and in 36 controls without aviophobia.

RESULTS

In keeping with the psychological perspective, we found a large increase in subjective distress (eta(2)=.43) during exposure to flight-related stimuli in the phobics and no change in subjective distress in the controls, whereas the physiological responses of both groups were indiscriminate. However, in keeping with the physiological perspective, we found that, within the group of phobics, increases in subjective fear during exposure were moderately strong coupled to HR (r =.208, P=.022) and cardiac vagal (r =.199, P=.028) reactivity. In contrast to predictions by the psychological perspective, anxiety sensitivity did not modulate this coupling.

CONCLUSION

We conclude that subjective fear responses and autonomic responses are only loosely coupled during mildly threatening exposure to flight-related stimuli. More ecologically valid exposure to phobic stimuli may be needed to test the predictions from the physiological and psychological perspectives.

Psychoendokrinologie der Angst

Zusammenfassung. Ätiologie, Symptomatik und Verlauf von Angststörungen sind multikausal zu erklären. Ein Teilaspekt der psychobiologischen Erklärungsansätze von Angststörungen sind endokrine Auffälligkeiten, anhand derer bestimmte Unterformen pathologischer Angst charakterisiert werden können. Vor allem die Hypothalamus-Hypophysen-Nebennierenrinde-Achse und das sympathiko-adrenomedulläre System werden im Zusammenhang mit Emotionsregulation und pathologischer Angst untersucht. Beide Hormonsysteme spielen bei der Anpassung an individuelle Belastungssituationen eine bedeutende Rolle und beeinflussen die psychobiologische Anpassung an angstauslösende Situationen nachhaltig. In dieser Überblicksarbeit werden endokrine Dysregulationen der o.g. Hormonsysteme für verschiedene Unterformen von Angststörungen aufgezeigt und bzgl. ihrer ätiologischen Bedeutsamkeit, auch unter Berücksichtigung genetischer Befunde, diskutiert. Darüber hinaus werden erste therapeutische Ansätze, bei denen psychoendokrinologische Methoden genutzt werden, aufgezeigt.

The origin of sympathetic outflow in heart failure: the roles of angiotensin II and nitric oxide

The regulation of sympathetic nerve activity in chronic heart failure (CHF) has been an area of renewed investigation. Understanding the central mechanisms that are responsible for sympatho-excitation in this disease state may help in reducing the deleterious effects of chronic sympatho-excitation. This review will summarize our understanding of abnormal reflex control of the circulation in CHF. The roles of the arterial baroreflex, the chemoreflex, the cardiac sympathetic afferent reflex and the cardiopulmonary reflex are discussed. New experimental techniques that allow genetic manipulation of substances such as nitric oxide synthase in discrete areas of the brain aid in clarifying the role of NO in the modulation of sympathetic tone in the CHF state. Lastly, clinical implications of this work are discussed.

Sympathetic reactivity in agoraphobic patients with and without personality disorders

OBJECTIVE

To compare sympathetic activity in agoraphobic patients with and without personality disorders before and after 11 weeks inpatient treatment.

METHODS

Agoraphobic patients (n=38), 84% with panic disorder and 47% with personality disorders underwent cold pressure test (CPT), mental stress test (MST), and a specific anxiety test (SAT). Psychological assessments were done by the Bodily Sensations Questionnaire (BSQ), the Agoraphobic Cognitions Questionnaire (ACQ), Spielberger STAI-1 and -2, and a Stress Test Anxiety (STA) questionnaire. Sympathetic activity was measured by blood pressure, heart rate, epinephrine, and norepinephrine.

RESULTS

The sympathetic activity did not differ significantly between patient groups, and the reactivity to stress was very low. The sympathetic reactivity remained unchanged after treatment, whereas psychiatric symptoms decreased. Correlations between sympathetic activity and psychological distress were not significant.

CONCLUSION

Interpretation of bodily signals seems to be more important than the actual sympathetic activity in agoraphobic patients.

Stress-induced hormonal and mood responses in scuba divers

The majority of injuries in scuba-divers are attributable to inappropriate behavior under stressful diving conditions, predominantly involving panic reactions emerging from elevated levels of anxiety. Divers with an elevated level of anxiety and poor coping are at higher risk of developing panic reactions than those possessing more adequate stress-coping-mechanisms. In the comparison of two extreme groups of seven divers each with opposite stress coping strategies, prolactin was found to be a hormonal marker with a significant increase in the sub-group of the stress-controllers. This hormonal response was observed in a recreational and a stressful dive, and in the latter with a more distinct elevation. Along with the self-reported emotional conditions under immersion, these data suggest that an increased prolactin level reflects a state of elevated physical and mental activation and vigilance. Facing a stressful situation subjects with more emotional concern and the tendency to surrender react by "blunted responses" and show significantly lower elevations of the prolactin levels in contrast to subjects with the very opposite psychological features. The other observed somatic parameters (epinephrine, norepinephrine) showed significant increases during and after dives (with the exception of saliva cortisol), however without any significant group difference.

Effect of circulating epinephrine on platelet function and hematocrit

We investigated the effect of raising arterial plasma epinephrine within the lower pathophysiological concentration range on various indicators of blood platelet function and hematocrit. Epinephrine was raised over 60 minutes by a stepwise increasing intravenous infusion in 40 healthy men aged 20 to 40 years. Platelet count increased progressively with increasing arterial epinephrine to a maximal change of 69 +/- 6 x 10(9)/L in EDTA-anticoagulated blood and a maximal change of 42 +/- 6 x 10(9)/L in acid-citrate-dextrose (ACD)-anticoagulated blood, and the weight of circulating platelets increased by 29% (P < .001). Platelet size increased significantly in EDTA and decreased in ACD, and the difference between EDTA and ACD was significant (P < .0001) for both count and size, suggesting that epinephrine not only recruits platelets into the circulation but also induces some microaggregation in vivo or adhesion ex vivo. Aggregation of platelets in vitro induced by epinephrine decreased (P < .003 for delta optical density and P = .038 for maximal optical density) after epinephrine infusion compared with saline but did not change when stimulated with ADP or collagen. These findings suggest a selective downregulation of the epinephrine-activating mechanisms concomitant with a rise in the platelet content of epinephrine by 81% (P < .001) and no change in the platelet sodium-proton membrane exchange. The release of granular content (beta-thromboglobulin and platelet factor 4) to the circulation in response to epinephrine was not significant. Thus, under acute conditions it seems that the platelets may protect themselves against inappropriate overstimulation by epinephrine. The importance of platelet epinephrine uptake is still unknown, but sodium-proton exchange does not seem to be involved in regulating the effects of circulating epinephrine on platelet function. Epinephrine has a pronounced effect on raising hematocrit (maximal change of 1.74 +/- 0.13 x 10(-2), P < .0001).

Extraversion as a modifying factor in catecholamine and behavioral responses to ethanol

Individual differences in catecholamine response to stress and ethanol were tested in extraverts and introverts on the basis of Eysenck's drug postulate claiming that introverts would be less susceptible to sedative drugs like ethanol. Forty-four healthy males received either 0.8 g/kg ethanol mixed into a drink of caffeine-free cola or a respective placebo and were tested with a stressful mental arithmetic task before and 40 min after the intake of the drink. Plasma catecholamines were determined from blood samples drawn at five defined intervals from an indwelling cannula and self-ratings on deactivation, relaxation, and anxiety were obtained as well as quality and quantity of performance in the arithmetic task. Results showed that there was no difference in catecholamine stress responses between introverts (Ex -) and extraverts (Ex +) before the drink, but that the intake of the fluid (both ethanol and placebo) resulted in higher norepinephrine (NE) increases in Ex - than in Ex +. The combined effects of ethanol and stress yielded larger responses of longer durations in Ex - than in Ex +. The concomitant psychological changes showed larger reductions in anxiety and increases in relaxation as well as larger decrements in quality of performance (% errors) in introverts in spite of their higher catecholamine increases. Thus, the predictions on the basis of arousal theory could not be verified experimentally and the drug postulate has to be modified in the sense that introverts probably have a higher depletion of NE in the central nervous system under physical but not under mental stress which is reflected by higher levels in the plasma and respective decreases in performance and activation.

Plasma catecholamine levels during exposure to an environment of hyperbaric oxygen

Plasma catecholamine levels were measured before, during and after hyperbaric oxygen therapy in nine subjects. Adrenaline levels were elevated immediately prior to hyperbaric oxygen therapy, but then fell and stabilized once treatment commenced. No significant fluctuations in plasma dopamine or noradrenaline levels were noted during the treatment period. This study does not support the premise that there is a suppression of endogenous plasma catecholamine levels during hyperbaric oxygen as has been previously reported. The observed initial increase in adrenaline can be attributed to stress/anxiety and the subsequent decline in this stress, rather than the result of the hyperbaric oxygen treatment itself.

Awareness of high blood pressure influences on psychological and sympathetic responses

The aim of the present study was to examine the effects of awareness of hypertension on psychological factors and whether there was an association between psychological and sympathetic responses. To avoid self-selection bias 32 19-yr old white men, all with mean blood pressure of 116 mm Hg were randomized into two groups. One group was informed that the blood pressure was elevated and asked to come to a second examination while the other was invited to take part in a coronary heart disease prevention program. A cold pressor test was undertaken and the subjects completed the Karolinska Scale of Personality (KSP). Assessed by the KSP, the informed group showed lower verbal aggression (p less than 0.01), irritability (p less than 0.05), monotony avoidance (p less than 0.05) and impulsiveness (p less than 0.05), higher detachment (p less than 0.05) but no significant differences in the other subscales like anxiety, psychasthenia or factors of hostility. Information significantly increased resting blood pressure and increments in heart rate and plasma adrenaline responses to cold pressor test. Thus, both psychological and sympathetic responses were influenced by awareness of high blood pressure. There were significant correlations between less assertive behaviour and increased plasma catecholamines.