The role of disgust in faintness elicited by blood and injection stimuli

An ethologically based view into human fear

The quality of the defensive response to a threat depends on the elements that trigger the fear response. The current classification system of phobias does not account for this. Here, we analyze the fear-eliciting elements and discern the different types of fears that originate from them. We propose Pain, Disgust, Vasovagal response, Visual-vestibular and postural interactions, Movement and Speed, Distance and Size, Low and mid-level visual features, Smell, and Territory and social status. We subdivide phobias according to the fear-eliciting elements most frequently triggered by them and their impact on behavior. We discuss the implications of a clinical conceptualization of phobias in humans by reconsidering the current nosology. This conceptualization will facilitate finding etiological factors in defensive behavior expression, fine-tuning exposure techniques, and challenging preconceived notions of preparedness. This approach to phobias leads to surprising discoveries and shows how specific responses bear little relation to the interpretation we might later give to them. Dividing fears into their potentially fear-eliciting elements can also help in applying the research principles formulated by the Research Domain Criteria initiative.

The Impact of Relational and Organizational-Environmental Aspects in Hospital Blood Collection: Clinical and Health Indications and New Training Needs

This study deals with people who underwent a blood test and consequently suffered a fainting episode in the past. This phenomenon affects many people and if not adequately dealt with, it can lead to a perception of the blood test as a serious and traumatic event, which could limit its use as a preventive diagnostic tool. These experiences have been explored by research mainly on the basis of the physiological mechanisms involved in fainting, with a few studies considering the actual lived experience related to the blood test. This study explored how this experience is lived and managed, capturing aspects that could facilitate blood tests and the procedures associated with them, thus it focused on people with vasovagal syncope and was articulated through the semi-structured interview methodology. Among the significant results is the importance of the relational aspects implemented by health staff, the differing organisation of the blood test procedure, the need to make the hospital environment less aseptic and more humanistic, effective actions to counter the anxieties relating to the administration of the blood test and the importance of including the blood test with an inter-disciplinarity perspective.

Different psychophysiological and clinical symptoms are linked to affective versus sensory vicarious pain experiences

For some people, seeing pain in others triggers a pain-like experience in themselves: these experiences can either be described in sensory terms and localized to specific body parts (sensory-localized, or S/L) or in affective terms and nonlocalized or whole-body experiences (affective-general, or A/G). In two studies, it is shown that these are linked to different clinical and psychophysiological profiles relative to controls. Study 1 shows that the A/G profile is linked to symptoms of Blood-Injection-Injury Phobia whereas the S/L profile shows some tendency toward eating disorders. Study 2 shows that the A/G profile is linked to poor interoceptive accuracy (for heartbeat detection) whereas the S/L profile is linked to higher heart-rate variability (HRV) when observing pain, which is typically regarded as an index of good autonomic emotion regulation. Neither group showed significant differences in overall heart rate, systolic blood pressure (SBP), or skin conductance response (SCR) when observing pain, and no overall differences in state or trait anxiety. Overall, the research points to different underlying mechanisms linked to different manifestations of vicarious pain response. Affective-General pain responders have strong subjective bodily experiences (likely of central origin given the absence of major differences in autonomic responsiveness) coupled with a worse ability to read objective interoceptive signals. Sensory-localized pain responders have differences in their ability to construct a multi-sensory body schema (as evidenced by prior research on the Rubber Hand Illusion) coupled with enhanced cardiovagal (parasympathetic) reactivity often indicative of better stress adaptation.

Large-Group One-Session Treatment: A Feasibility Study of Exposure Combined With Applied Tension or Diaphragmatic Breathing in Highly Blood-Injury-Injection Fearful Individuals

Objective: Large-group one-session treatments (LG-OSTs) might represent a promising treatment tool as increasing evidence suggests their effectiveness in individuals with different situational fears. In the present study, we explored feasibility and effectiveness of an exposure-based LG-OST protocol applying applied tension and diaphragmatic breathing as coping strategies in a sample of 40 individuals, highly fearful of blood-injury-injection (BII).

Method: We assessed participants’ BII-fear using questionnaires and a behavioral approach test (BAT) before and after treatment, consisting of a blood-drawing procedure. Stability of treatment effects was assessed via online-survey at 7-month follow-up.

Results: The LG-OST procedure evidenced feasible and effective. Pre-post treatment comparisons showed medium to large treatment effects (d = 0.40–0.93) regarding the questionnaire measures. After being treated, 70% of the individuals successfully underwent a blood drawing. Moreover, participants continued to improve in the post follow-up interval leading to large treatment effects (d = 1.19–1.62).

Conclusion: In treating BII-fear, LG-OSTs might not only serve within a framework of a stepped care approach but also could represent a useful single-treatment option. Additionally, due to their high efficiency and standardization of treatment delivery, LG-OST protocols might foster research at the interface of basic and clinical research.

Is Disgust Proneness Associated With Anxiety and Related Disorders? A Qualitative Review and Meta-Analysis of Group Comparison and Correlational Studies

Research suggests that disgust may be linked to the etiology of some anxiety-related disorders. The present investigation reviews this literature and employs separate meta-analyses of clinical group comparison and correlational studies to examine the association between disgust proneness and anxiety-related disorder symptoms. Meta-analysis of 43 group comparison studies revealed those high in anxiety disorder symptoms reported significantly more disgust proneness than those low in anxiety symptoms. Although this effect was not moderated by clinical versus analogue studies or type of disorder, larger group differences were observed for those high in anxiety symptoms associated with contagion concerns compared to those high in anxiety symptoms not associated with contagion concerns. Similarly, meta-analysis of correlational data across 83 samples revealed moderate associations between disgust proneness and anxiety-related disorder symptoms. Moderator analysis revealed that the association between disgust proneness and anxiety-related disorder symptoms was especially robust for anxiety symptoms associated with contagion concerns. After controlling for measures of negative affect, disgust proneness continued to be moderately correlated with anxiety-related disorder symptoms. However, negative affect was no longer significantly associated with symptoms of anxiety-related disorders when controlling for disgust proneness. The implications of these findings are discussed in the context of a novel transdiagnostic model.

Treatment of intra-oral injection phobia: a randomized delayed intervention controlled trial among Norwegian 10- to 16-year-olds

OBJECTIVE

To evaluate the effect of five sessions of cognitive behavioural therapy (CBT) for 10- to 16-year-olds with intra-oral injection phobia.

MATERIAL AND METHODS

This was a randomized delayed intervention controlled trial in 67 patients, fulfilling the DSM-5 criteria for specific phobia. All patients received the same CBT performed by dentists specially trained in CBT. The patients were randomly assigned to either an immediate treatment group (ITG) (34 patients) or a waitlist-control group (WCG) (33 patients). The WCG was put on a waitlist for 5 weeks. After treatment, all patients were combined for post-treatment analyses. Assessments including the psychometric self-report scales Intra-oral injection fear scale (IOIF-s), Children's Fear Survey Schedule-Dental Subscale (CFSS-DS), Injection Phobia Scale for children (IS-c) and Mutilation Questionnaire for children (MQ-c) and a behavioural avoidance test (BAT) followed by a questionnaire on cognitions during the BAT, occurred pre-, post-treatment/waitlist and at a 1-year follow-up.

RESULTS

CBT had a significant effect compared to no treatment (WCG). After treatment, the scores on the psychometric self-report scales were significantly reduced and higher levels in the BAT were achieved. The results were maintained at 1-year follow-up. Of the 67 patients, 70.1% received intra-oral injections during CBT treatment, whereas 69.4% of those completing the CBT, in need for further dental treatment, managed to receive the necessary intra-oral injections at their regular dentist.

CONCLUSIONS

The 10- to 16-year-olds diagnosed with intra-oral injection phobia benefitted positively on CBT performed by specially trained dentists.

Reliability, validity and cutoff score of the Intra-Oral Injection Fear scale

BACKGROUND

A proper assessment tool is needed to gain more knowledge about fear of intraoral injections in children.

AIM

The aims of this study were to evaluate the reliability and validity of the novel Intra-Oral Injection Fear scale (IOIF-s) and to establish a cutoff score for a high level of such fear.

METHODS

Data were obtained from two samples of 10- to 16-year-olds in Hordaland, Norway. Sample I, 1460 pupils attending elementary and high schools, provided questionnaire-based data. The survey instruments used were IOIF-s, Children's Fear Survey Schedule-Dental Subscale (CFSS-DS), Mutilation Questionnaire for Children (MQ-c) and Injection phobia Scale for Children (IS-c). Sample II was 67 patients, diagnosed with intraoral injection phobia at the Center for Odontophobia, Oral Health Center of Expertise in Western Norway-Hordaland, who provided IOIF-s data.

RESULTS

Cronbach's alpha was 0.95. The IOIF-s discriminated between subjects with and without intraoral injection phobia and was associated with the other survey instruments of similar construct. Principal component analysis revealed a two-component solution, characterized as 'Contact Fear' and 'Distal Fear'. Receiver-operating characteristic (ROC) curve indicated that a cutoff score of 38 was appropriate.

CONCLUSION

The IOIF-s showed satisfying psychometric properties in terms of reliability and validity.

Disgust stimuli reduce heart rate but do not contribute to vasovagal symptoms

BACKGROUND AND OBJECTIVES

The vasovagal response demonstrates a unique form of stress response, common in medical settings yet provoked by a variety of blood-injury-injection stimuli. This study aimed to better understand the psychophysiological mechanisms of the vasovagal response..

METHODS

16 undergraduates with and 42 without a self-reported history of fainting watched five 3-5 min videos with different emotional content. One documentary clip (Neutral condition) described a campus environmental project while another (Blood/Injury) depicted portions of an open heart surgery. Three additional clips were also used, including Medical, Threat, and Contamination stimuli. Vasovagal symptoms and physiological variables were assessed during each video.

RESULTS

As predicted, while the disgust-related stimuli (Blood/Injury, Medical, Contamination) were associated with generally lower heart rate, the Blood/Injury video produced the highest symptoms and the only significant difference between previous fainters and non-fainters. The physiological measures also revealed that participants with a fainting history experienced higher stroke volume and lower systolic blood pressure throughout, as well as several main effects of video.

LIMITATIONS

An additional decrease in systolic blood pressure and respiration produced by watching the Blood/Injury video may have been sufficient to trigger symptoms in some, though results also suggest that systemic variables do not entirely explain susceptibility to symptoms. More careful evaluation of regional blood flow may be required.

CONCLUSIONS

Participants who had previously experienced strong vasovagal responses displayed what appeared to be an anticipatory response to the Blood/Injury video. Finally, disgust stimuli may reduce heart rate but do not appear to contribute to vasovagal symptoms.

Media Discourse on the Social Acceptability of Fecal Transplants

Advances in human microbiome research have generated considerable interest in elucidating the role of bacteria in health and the application of microbial ecosystem therapies and probiotics. Fecal transplants involve the introduction of gut microbes from a healthy donor's stool to the patient and have been documented as effective for treating Clostridium difficile infections (CDIs) and some other gastrointestinal disorders. However, the treatment has encountered regulatory hurdles preventing widespread uptake. We examined dominant representations of fecal transplants in Canadian media and found that fecal transplants are often represented as being inherently disgusting or distasteful (the "ick factor"). This "ick factor" is used to construct different messages about the treatment's social acceptability and legitimacy. We conclude that an over-emphasis on the "ick factor" constrains public discourse from a more nuanced discussion of the social challenges, scientific concerns, and regulatory issues surrounding the treatment.

Explaining Vampirism: Two Divergent Attractors of Dead Human Concepts

This paper explores the cognitive foundations of vampirism beliefs. The occurrence of beliefs of the dead rising from graves and returning to harm the living across many cultures indicates that this concept has features that make it successful in the process of cultural transmission. Comparing ghost- and vampire-like beliefs, it is argued that bodiless agents and animated but dead bodies represent two divergent cognitive attractors concerning concepts of dead humans. The inferential potential of the classic idea of a bodiless ghost is based on intuitions produced by the mental system of Theory of Mind, while the traditional concepts of a vampire attribute to the dead only minimal intentionality. The inferential potential of a vampire is based on the system of disease avoidance and the emotion of disgust related to the dead body. Vampirism beliefs represent a cognitively attractive combination of a hazard and relevant actions to eliminate it: they postulate a threat of an animated corpse and relevant behavioral reaction, namely fatal interventions on vampire’s body.

Cardiovascular activity in blood-injection-injury phobia during exposure: evidence for diphasic response patterns?

Exposure to feared stimuli in blood-injection-injury (BII)-phobia is thought to elicit a diphasic response pattern, with an initial fight-flight-like cardiovascular activation followed by a marked deactivation and possible fainting (vasovagal syncope). However, studies have remained equivocal on the importance of such patterns. We therefore sought to determine the prevalence and clinical relevance of diphasic responses using criteria that require a true diphasic response to exceed cardiovascular activation of an emotional episode of a negative valence and to exceed deactivation of an emotionally neutral episode. Sixty BII-phobia participants and 20 healthy controls were exposed to surgery, anger and neutral films while measuring heart rate, blood pressure, respiratory pattern, and end-tidal partial pressure of carbon dioxide (as indicator of hyperventilation). Diphasic response patterns were observed in up to 20% of BII-phobia participants and 26.6% of healthy controls for individual cardiovascular parameters. BII-phobia participants with diphasic patterns across multiple parameters showed more fear of injections and blood draws, reported the strongest physical symptoms during the surgery film, and showed the strongest tendency to hyperventilate. Thus, although only a minority of individuals with BII phobia shows diphasic responses, their occurrence indicates significant distress. Respiratory training may add to the treatment of BII phobia patients that show diphasic response patterns.

[Blood-injection-injury phobia: Physochophysiological and therapeutical specificities]

INTRODUCTION

Seventy-five percent of patients with blood-injection-injury phobia (BII-phobia) report a history of fainting in response to phobic stimuli. This specificity may lead to medical conditions remaining undiagnosed and untreated, incurring considerable cost for the individual and society. The psychophysiology of BII-phobia remains poorly understood and the literature on effective treatments has been fairly sparse. Aims of the systematic review: to synthesize the psychophysiology of BII-phobia and to propose a systematic review of the literature on effectiveness of different treatments evaluated in this indication.

RESULTS

Firstly, the most distinct feature of the psychophysiology of BII-phobia is its culmination in a vasovagal syncope, which has been described as biphasic. The initial phase involves a sympathetic activation as is typically expected from fear responses of the fight-flight type. The second phase is characterized by a parasympathetic activation leading to fainting, which is associated with disgust. Subjects with syncope related to BII-phobia have an underlying autonomic dysregulation predisposing them to neurally mediated syncope, even in the absence of any blood or injury stimulus. Many studies report that BII-phobic individuals have a higher level of disgust sensitivity than individuals without any phobia. Secondly, behavioral psychotherapy techniques such as exposure only, applied relaxation, applied tension, and tension only, have demonstrated efficacy with no significant difference between all these techniques. The disgust induction has not improved effectiveness of exposure.

CONCLUSION

We have explained the psychophysiology of BII-phobia, the understanding of which is required to study and validate specific techniques, in order to improve the prognosis of this disorder, which is a public health issue.

The effects of blood-draw and injection stimuli on the vasovagal response

Vasovagal reactions (VVR) are common, complicating and deterring people from various medical procedures. A recent perspective (R. R. Diehl, ) suggests that VVR developed from the adaptive process of hemorrhagic fainting, perhaps as a means of preparing for anticipated blood loss. The primary goal of this study was to compare vasovagal symptoms during intravenous-injection and blood-draw videos. Sixty-two young adults watched the videos. Vasovagal symptoms were assessed with self-report, blood pressure, and heart rate variability. As predicted, participants reported more vasovagal symptoms and anxiety following the blood-draw video. Sympathetic nervous system activity (low- to high-frequency ratio) decreased during both videos but significantly more during the blood-draw video, although this could be reversed by the Applied Tension technique. Results are discussed in terms of the relevance of specific stimuli and emotions in VVR.

The relation between disgust-sensitivity, blood-injection-injury fears and vasovagal symptoms in blood donors: disgust sensitivity cannot explain fainting or blood donation-related symptoms

BACKGROUND AND OBJECTIVES

Page's (1994) prominent theory for the explanation of fainting in blood-injection-injury situations holds that disgust sensitivity contributes to syncopal reactions. We investigated if blood donation-related vasovagal symptoms (1) or fainting related to blood donations (2) are associated with disgust sensitivity.

METHODS

In an online sample of 361 blood donors, we assessed blood-injection-injury fears, disgust sensitivity, history of blood donation related fainting and retrospective self-ratings of vasovagal symptoms. For the assessment of blood-injection-injury fears we used the BII-Q which has excellent psychometric properties and does not confound disgust and anxiety sensitivity. Vasovagal symptoms were measured by the Blood Donation Reactions Inventory (BDRI) which captures mild and strong vasovagal symptoms and has been used in previous studies with blood donors.

RESULTS

Disgust sensitivity did not significantly contribute to the explanation of self-reported vasovagal symptoms in a regression model with gender, blood-injection-injury fear and disgust sensitivity as predictors. We did not find any significant group differences in disgust sensitivity for blood donors with or without a fainting history (statistical power = 0.95) and a Bayesian model selection procedure showed that it is more likely that both groups are equally disgust sensitive than it is that the fainters are more disgust sensitive.

LIMITATIONS

Further research is required to confirm the findings in prospective studies.

CONCLUSION

Our results indicate that disgust sensitivity is not relevant for the development of vasovagal syncopes.

Effects of experienced disgust on habituation during repeated exposure to threat-relevant stimuli in blood-injection-injury phobia

Despite growing evidence implicating disgust in the etiology of blood-injection-injury (BII) phobia, the relevance of disgust for exposure-based treatment of BII phobia remains largely unknown. Individuals with BII phobia were randomly assigned to a disgust (view vomit videos) or neutral activation (view waterfall videos) condition. They were then exposed to 14 videotaped blood draws, during which fear and disgust levels were repeatedly assessed. Participants then engaged in a behavioral avoidance test (BAT) consisting of exposure to threat-relevant stimuli. Examination of outcome comparing the identical first and last blood-draw clips revealed that fear and disgust toward blood draws was significantly reduced in both groups. Disgust levels were also found to be more intense for the video stimuli relative to fear levels whereas the opposite was true for BAT stimuli. Contrary to predictions, the disgust induction did not enhance reductions in negative responses to the target video or reduce behavioral avoidance. Growth curve analyses did show that individuals with BII phobia exposed to the disgust induction showed greater initial fear levels during repeated exposure than those in the neutral condition. However, this effect was not consistently observed across different analytic approaches. Changes in fear during exposure were also found to be independent of changes in disgust but not vice versa, and greater initial fear levels during repeated exposure to threat was associated with fear and disgust levels during the BAT. The implications of these findings for conceptualizing the role of disgust in etiology and treatment of BII phobia are discussed.

Development and Initial Validation of the Medical Fear Survey–Short Version

The present investigation employs item response theory (IRT) to develop an abbreviated Medical Fear Survey (MFS). Application of IRT analyses in Study 1 ( n = 931) to the original 50-item MFS resulted in a 25-item shortened version. Examination of the location parameters also resulted in a reduction of the Likert-type scaling of the MFS by removing the last response category (“Terror”). The five subscales of the original MFS were highly correlated with those of the MFS–short version. The short version also displayed comparable convergent and discriminant validity with the original MFS in relation to measures of fear, disgust, and anxiety. Confirmatory factor analysis in Study 2 revealed that the five-factor structure of the MFS–short form fit the data well in U.S. ( n = 283) and Dutch ( n = 258) samples. The short form also had comparable convergent and discriminant validity with the original MFS in relation to domains of disgust in both samples. Receiver operating characteristic (ROC) analysis in Study 3 demonstrated that the subscales of the short version were comparable with the original MFS in classifying participants high ( n = 40) and low ( n = 40) in blood/injection phobia. Last, structural equation modeling in Study 4 ( n = 113) revealed that the MFS–short form demonstrated excellent convergent/discriminant validity with strong associations with injection fear and no association with spider fear. These findings suggest that the MFS–short form has considerable strengths, including decreased assessment time, while retaining sound psychometric properties.

Fear-related predictors of vasovagal symptoms during blood donation: it's in the blood

A recent theory proposes that emotional fainting developed from an earlier adaptive characteristic, fainting in response to hemorrhage. Despite potential loss of consciousness, a dramatic decrease in blood pressure improves chances of survival in animals with severe wounds by reducing blood loss and facilitating clotting. Humans may have developed the characteristic of emotional fainting as a response to anticipated blood loss. This idea suggests that people with stronger fears of blood should be especially susceptible to fainting and milder vasovagal symptoms such as dizziness and lightheadedness. Two samples of young adult blood donors (N = 276 and 663) who completed the Medical Fears Survey (MFS) were studied. Items from the MFS related to fears of blood, needles, and mutilation were used to predict self-reported dizziness and nurse-initiated treatment for vasovagal reactions. In both samples, fears of experiencing or seeing blood loss were more closely associated with both subjective and objective measures of vasovagal reactions, despite the fact that other fears (e.g., fears related to needles) were more common overall. Better understanding of the mechanisms of vasovagal reactions has both theoretical and clinical implications, such as improving means of coping with invasive medical procedures.

The Multi-Dimensional Blood/Injury Phobia Inventory: its psychometric properties and relationship with disgust propensity and disgust sensitivity

The Multi-Dimensional Blood Phobia Inventory (MBPI; Wenzel & Holt, 2003) is the only instrument available that assesses both disgust and anxiety for blood-phobic stimuli. As inflated levels of disgust propensity (i.e., tendency to experience disgust more readily) are often observed in blood phobia, the MBPI appears a promising instrument for disgust research. First, we examined its psychometric properties. Next, it was examined whether disgust sensitivity (i.e., considering experiencing disgust as something horrid) had added predictive value compared to disgust propensity in blood phobia. Therefore, students and university employees (N = 616) completed the MBPI, indices on blood phobia, disgust propensity and sensitivity. The MBPI proved to be reliable and valid. Further, it correlated moderately to high with disgust propensity and sensitivity. Additionally, disgust propensity and sensitivity were both significant predictors for blood phobia. In conclusion, the MBPI appears a valuable addition to the currently available arsenal of indices to investigate blood phobia.

Late cortical positivity and cardiac responsitivity in female dental phobics when exposed to phobia-relevant pictures

OBJECTIVES

Dental phobia is currently classified as a specific phobia of the blood-injection-injury (BII) subtype. In another subtype, animal phobia, enhanced amplitudes of late event-related potentials have consistently been identified for patients during passive viewing of disorder-relevant pictures. However, this has not been shown for BII phobics, and studies with dental phobics are lacking. Findings on cardiac responses in BII phobia during exposure are heterogeneous, as some studies showed a diphasic pattern of heart rate acceleration and deceleration, whereas others observed pure acceleration. In contrast, heart rate increase has consistently been shown for dental phobics, resembling the reaction of animal phobics. Moreover, the BII subtype is characterized by elevated disgust reactivity whereas the role of habitual disgust proneness in dental phobia is unclear.

METHODS

We recorded the electroencephalogram and the electrocardiogram from 18 dental phobic and 18 healthy women while they watched pictures depicting dental treatment, disgust, fear and neutral items.

RESULTS

Phobics relative to controls showed an enhanced late positive potential (300-700 ms) and heart rate acceleration towards phobic material, reflecting motivated attention and fear. Affective ratings revealed that dental phobics experienced significantly higher levels of fear than disgust during exposure to phobia-relevant material. Patients' elevated habitual disgust proneness was restricted to specific domains, such as the oral incorporation of offensive objects.

CONCLUSION

The psychophysiology of dental phobia resembles the fear-dominated subtypes of specific phobia reported in earlier studies. Future studies should continue to investigate whether the current classification of this disorder as BII phobia needs to be reconsidered.

Disgust, anxiety, and vasovagal syncope sensations: a comparison of injection-fearful and nonfearful blood donors

Although research has implicated disgust in the fainting response observed in blood-injection-injury (BII) phobia, this finding has not been consistently observed in the literature. The present study further examines the relationship between disgust and fainting symptoms among injection-fearful (n=108) and nonfearful (n=338) blood donors. Volunteers from community blood drives provided pre-donation levels of anxiety and disgust towards giving blood and completed a standardized measure of vasovagal reactions (fainting) to blood donation after giving blood. As predicted, injection-fearful participants reported significantly more pre-donation anxiety and disgust compared to nonfearful participants. Injection-fearful donors also reported experiencing more fainting symptoms during blood donation and found the donation experience more unpleasant than did nonfearful participants. Although pre-donation disgust and anxiety levels each uniquely predicted fainting symptoms among nonfearful donors, only pre-donation anxiety uniquely predicted fainting symptoms among injection-fearful donors. Implications of these findings for conceptualizing the disgust-faint relationship in BII phobia are discussed.

The psychophysiology of blood-injection-injury phobia: looking beyond the diphasic response paradigm

Blood-injection-injury (BII) phobia is an anxiety disorder that may be accompanied by vasovagal fainting during confrontation with the feared stimuli. The underlying pattern of autonomic regulation has been characterized as a diphasic response, with initial increases in heart rate and blood pressure that are typical of a fight-flight response, and subsequent drops in blood pressure and/or heart rate that may precipitate vasovagal fainting. Tensing skeletal muscles of the arms, legs, and trunk (applied tension) has been proposed as a technique to cope with this dysregulation. This review critically examines the empirical basis for the diphasic response and its treatment by applied tension in BII phobia. An alternative perspective on the psychophysiology of BII phobia and vasovagal fainting is offered by focusing on hypocapnia that leads to cerebral blood flow reductions, a perspective supported by research on neurocardiogenic and orthostatically-induced syncope. The evidence may indicate a role for respiration-focused coping techniques in BII phobia.

Is disgust associated with psychopathology? Emerging research in the anxiety disorders

Recent evidence indicates that the propensity towards experiencing disgust may contribute to the development and maintenance of some anxiety disorders. This article summarizes the empirical evidence with emphasis on illuminating potential mediators, moderators, and mechanisms of the disgust-anxiety disorder association that may inform the development of an integrative conceptual model. Early research using neuroimaging methods suggest that disgust processing is associated with activation of the insula. This research has the potential to facilitate progress in developing an empirically informed psychobiological theory on the causal role of disgust in the anxiety disorders.

Dissociation Following Traumatic Stress

We postulate that the cascade “Freeze-Flight-Fight-Fright-Flag-Faint” is a coherent sequence of six fear responses that escalate as a function of defense possibilities and proximity to danger during life-threat. The actual sequence of trauma-related response dispositions acted out in an extremely dangerous situation therefore depends on the appraisal of the threat by the organism in relation to her/his own power to act (e.g., age and gender) as well as the perceived characteristics of threat and perpetrator. These reaction patterns provide optimal adaption for particular stages of imminence. Subsequent to the traumatic threats, portions of the experience may be replayed. The actual individual cascade of defense stages a survivor has gone through during the traumatic event will repeat itself every time the fear network, which has evolved peritraumatically, is activated again (i.e., through internal or external triggers or, e.g., during exposure therapy).When a parasympathetically dominated ‘‘shut-down’’ was the prominent peri-traumatic response during the traumatic incident, comparable dissociative responses may dominate responding to subsequently experienced threat and may also reappear when the traumatic memory is reactivated. Repeated experience of traumatic stress forms a fear network that can become pathologically detached from contextual cues such as time and location of the danger, a condition which manifests itself as posttraumatic stress disorder (PTSD). Intrusions, for example, can therefore be understood as repetitive displays of fragments of the event, which would then, depending on the dominant physiological response during the threat, elicit a corresponding combination of hyperarousal and dissociation. We suggest that trauma treatment must therefore differentiate between patients on two dimensions: those with peritraumatic sympathetic activation versus those who went down the whole defense cascade, which leads to parasympathetic dominance during the trauma and a corresponding replay of physiological and dissociative responding, when reminded. The differential management of dissociative stages (“fright” and “faint”) has important treatment implications.

Incremental specificity of disgust propensity and sensitivity in the prediction of health anxiety dimensions

The present study sought to determine the incremental specificity of disgust propensity and sensitivity in the prediction of symptoms of health anxiety in a large nonclinical sample (N=498). Exploratory factor analysis identified Illness Likelihood, Illness Severity, and Body Vigilance as dimensions of health anxiety symptoms that significantly correlated with disgust propensity and sensitivity. Negative affect and the fear of contamination were also significantly correlated with the three health anxiety symptom dimensions. Regression analyses did show that disgust propensity and sensitivity predicted overall health anxiety symptoms independent of negative affect and fear of contamination. However, the unique association between disgust propensity and sensitivity and symptoms of health anxiety was specific to the Body Vigilance dimension. These findings suggest that disgust propensity and sensitivity may be a unique vulnerability for the vigilance for bodily sensations/changes aspect of health anxiety but not necessarily other (perceived probability/severity of having a serious illness) aspects of health anxiety. The clinical and research implications of these findings for conceptualizing disgust propensity and sensitivity as a vulnerability for excessive health anxiety are discussed.

Evaluative conditioning of fear and disgust in blood-injection-injury phobia: specificity and impact of individual differences in disgust sensitivity

The present study examines whether the repeated pairing of neutral facial expressions with phobic-relevant stimuli differentially influences evaluative ratings of fear and disgust between analogue blood-injection-injury (BII) phobic (n=40) and non-phobic (n=40) participants. Consistent with prior research, BII phobics reported greater disgust sensitivity than non-phobic participants even after controlling for between group differences in anxiety symptoms. Results from the evaluative conditioning experiment indicated that pre- to posttest increases in fear ratings were only marginally greater for phobic compared to non-phobic participants. However, increases in disgust from pre- to posttest were greater for phobic compared to non-phobic participants and greater for neutral expressions that were paired with threat-relevant stimuli compared to stimuli not paired with threat-relevant stimuli. Subsequent analysis also indicated that pre- to posttest increases in disgust ratings of neutral expressions that were paired with threat-relevant stimuli was moderated by disgust sensitivity levels among phobic and non-phobic participants. Heightened fear and disgust ratings were subsequently reduced by an extinction procedure. Implications of present findings in understanding the role of fear and disgust in BII phobia are discussed.

Cardiovascular dynamics in blood phobia: evidence for a key role of sympathetic activity in vulnerability to syncope

This study was aimed at clarifying the mechanism predisposing people with blood phobia to syncope by investigating the complete hemodynamic response pattern and the underlying autonomic control. Blood phobics and controls were shown 3 film-clips: phobia-related, phobia-unrelated, and neutral. Hemodynamic responses were recorded using impedance cardiography and Finapres. Preejection period and respiratory sinus arrhythmia were employed as indices of cardiac sympathetic and parasympathetic activity. Self-ratings of emotion were also collected. Blood phobics displayed global heart rate and cardiac output increases to the phobic film, mediated by augmented cardiac sympathetic activity. Systolic blood pressure and total peripheral resistance markedly declined, with no evidence of diphasic reaction or parasympathetic activation. An impaired vasomotor response under sympathetic control might be the key mechanism underlying the phobic dysfunctional response.

Behavioral avoidance and self-reported fainting symptoms in blood/injury fearful individuals: an experimental test of disgust domain specificity

This study examined the specificity of disgust in predicting avoidance in blood/injury (BI) phobia. Participants high (n=38) and low (n=46) in BI fear completed measures of disgust across multiple domains and severity of BI-related fear. They then completed three randomly presented behavioral avoidance tasks (BATs) that consisted of exposure to a 15'' severed deer leg (BI task), a live spider (spider task), and a 'contaminated' cookie (cookie task). Fainting symptoms associated with each BAT were recorded as well. When controlling for gender and BI fear group membership, mutilation disgust contributed unique variance to avoidance on the BI task and animal disgust contributed unique variance to avoidance on the spider task. None of the disgust domains contributed unique variance to avoidance on the cookie task. For the high BI fear group, self-reported fainting symptoms were more pronounced during the BI and spider BAT than during the cookie BAT. Although mutilation disgust was significantly associated with self-reported fainting symptoms on the BI task among the high BI fear group, this relationship became nonsignificant when controlling for BI-related fear severity. Implications of the domain specificity of disgust and its relevance for understanding fainting responses in BI phobia are discussed.

The Disgust Propensity and Sensitivity Scale-Revised: psychometric properties and specificity in relation to anxiety disorder symptoms

The present study examined the factor structure and psychometric properties of the Disgust Propensity and Sensitivity Scale-Revised (DPSS-R) in a nonclinical sample (N=340). Principal components analysis of the DPSS-R revealed a two-factor structure consisting of Disgust Propensity and Disgust Sensitivity. Although the two-factor structure converged well with prior research, four of the 16 DPSS-R items did not load onto the predicted factor. The DPSS-R demonstrated good reliability and validity. The DPSS-R and its two factors were moderately correlated with spider fear and contamination fear and mildly correlated with injection fear. The relation between the DPSS-R and these anxiety disorder symptoms remained largely intact after controlling for negative affect. Regression analyses also revealed that the two DPSS-R factors demonstrate specificity in the prediction of anxiety disorder symptoms. These findings are discussed in terms of promoting a more valid and reliable assessment of disgust in anxiety disorders.

Blood-injection-injury fears: harm- vs. disgust-relevant selective outcome associations

There is increasing evidence that blood-injection-injury (BII) phobia is qualitatively different from the other specific phobias in the sense that phobic distress takes the form of disgust rather than (threat-induced) fear. Following this, we tested the relative importance of harm and disgust-related associative biases in BII-fear. High (n=25) and low (n=27) fearful individuals saw a series of fear-relevant (blood-related) and fear-irrelevant (rabbit and flower) slides which were randomly paired with either a harm-related outcome, a disgust-related outcome, or nothing. Preexperimentally, participants expected blood-related slides to be followed by both disgust- and harm-relevant outcomes. These selective preexperimental outcome expectancies were readily corrected during the experiment. Neither low nor high fearful participants showed a postexperimental covariation bias. The absence of differential effects between high and low fearful participants does not support the idea that disgust- or harm-relevant associative biases play a role in the maintenance of BII-fears. The results corroborate the previous finding of Pury and Mineka [1997. Covariation bias for blood-injury stimuli and aversive outcomes. Behaviour Research and Therapy, 35, 35-47] that people are generally liable to selectively associate BII-stimuli with aversive outcomes.

Structural differentiation of disgust from trait anxiety in the prediction of specific anxiety disorder symptoms

Research has begun to implicate the role of disgust in the etiology of specific phobias and obsessive-compulsive disorder (OCD). However, it remains unclear if the association between disgust and specific anxiety disorder symptoms is an artifact of trait anxiety or a potential mechanism through which trait anxiety effects specific anxiety disorder symptoms. The present study employed structural equation modeling to differentiate disgust from trait anxiety in the prediction of four types of specific anxiety disorder symptoms in a non-clinical sample (N=352). Results indicate that disgust and trait anxiety latent factors were independently related to spider fears, blood-injection-injury (BII) fears, general OCD symptoms, and OCD washing concerns. However, when both variables were simultaneously modeled as predictors, latent disgust remained significantly associated with the anxiety disorder symptoms, whereas the association between latent trait anxiety and the anxiety disorder symptoms became non-significant or was substantially reduced. Statistical tests of intervening variable effects converged in support of disgust as a significant intervening variable between trait anxiety and spider fears, BII fears, and OCD symptoms (particularly washing concerns). The relevance of these findings for future research investigating the role of disgust in specific anxiety disorders is discussed.

Examination of the decline in fear and disgust during exposure to threat-relevant stimuli in blood-injection-injury phobia

In the present study, participants (N=22) displaying marked fear of blood-injection-injury (BII) stimuli were provided 30 min of in vivo exposure to threat-relevant stimuli, during which time their fear and disgust levels were repeatedly assessed. Growth curve analyses were then conducted to examine the decay slopes in both fear and disgust and their relationship. Results indicated that exposure led to significant declines in fear and disgust across trials. However, the decay slope observed for fear was significantly greater than that for disgust. Further analyses revealed that the decline in fear across trials remained significant after accounting for the changes in disgust. However, the effect of trial on disgust was no longer significant after controlling for the reduction in fear. Global disgust sensitivity levels prior to exposure did not moderate the level of fear activation or fear reduction during exposure. BII-specific digust sensitivity was also not associated with initial levels of fear. However, levels of BII-specific disgust sensitivity were independently negatively associated with fear decline. Theoretical and clinical implications of the findings are discussed.

Disgust and psychiatric illness: have we remembered?

It has been argued that disgust has been forgotten by psychiatry. An overview of recent research on disgust is provided. Findings suggest that disgust is a predictor of the development of specific psychiatric conditions.

Fear of needles and vasovagal reactions among phlebotomy patients

Anxiety associated with blood and injections is a common problem in medical settings and, in severe cases, affects sufferers' ability to receive medically essential treatment. The present study was conducted to examine incidence of adverse reactions to venipunctures among phlebotomy patients, as well as to understand the demographic and psychological characteristics associated with such reactions. A large sample of participants undergoing venipuncture (N=3315) was recruited from hospital-based phlebotomy laboratories. Participants completed a brief questionnaire assessing psychological and physiological reactions to having their blood drawn. Results indicated that a small minority of patients experienced significant anxiety symptoms during venipuncture. Vasovagal reactions and vasovagal syncope were extremely infrequent. A tendency to experience pain, disgust, and fear of fainting during injections was associated with anxious responding to the venipuncture and a probable diagnosis of needle phobia. Theoretical and practical implications are discussed.

Disgust, anxiety and fainting symptoms associated with blood-injection-injury fears: a structural model

The present study examines the structural relations between disgust sensitivity, anxiety symptoms, blood-injection-injury (BII) fears, and fainting symptoms associated with BII fears in 259 nonclinical participants. Results revealed that both disgust and BII fear were independent predictors of fainting symptoms. However, structural equation modeling revealed that the relation between disgust sensitivity and fainting was reduced to negative and non-significance when the path from BII fear to fainting was also introduced. Subsequent analysis indicated that the relation between disgust sensitivity and fainting symptoms was fully mediated by BII fear. It was also found that animal reminder disgust was related to fainting symptoms whereas core disgust was not. However, the relation between animal reminder disgust and fainting was also fully mediated by BII fear. Furthermore, anxiety symptoms did not add directly to the structural model predicting fainting associated with BII fears. Implications of these findings for better understanding the interaction of the emotional mechanisms that mediate fainting responses in BII phobia are discussed.

The neurocircuitry of obsessive-compulsive disorder and disgust

Recent evidence from human research has indicated that discrete regions of the brain control different basic emotions. Whether the recognition and formulation of emotions truly stem from compartmentalized systems or arise from a multidimensional framework has yet to be elucidated, however. Disgust is a basic emotion that has been hypothesized to constitute an evolutionary function of contamination and disease avoidance. Disgust involves the appraisal of objects and events for their potential role in contamination, and OCD conceivably involves a dysfunction of this appraisal process. Disgust sensitivity has been shown to be positively correlated with OCD and to significantly predict contamination fear. Likewise, functional imaging studies of OCD patients with contamination concerns demonstrate activation of the same neural regions with disgust-inducing pictures as symptom relevant stimuli. Therefore, the neurocircuits involved in disgust processing may be relevant to OCD and, in particular, the contamination subtype. This review focuses on describing what is known to date concerning the neurocircuitry of disgust, and its relevance to the apparent neurocircuitry of OCD.

The structural relation between disgust sensitivity and blood-injection-injury fears: a cross-cultural comparison of US and Dutch data

A growing body of literature has implicated the role of disgust sensitivity in blood-injection-injury (BII) phobia. The present study sought to extend this line of research by investigating the structural relation between Rozin et al.'s [(2000). Disgust. In M. Lewis, J.M. Haviland (Eds.), Handbook of emotions. New York: Guilford Publications.] theoretical model of core and animal reminder disgust as they relate to BII fears in US (N = 162) and Dutch (N = 260) samples. Using confirmatory factor analysis (CFA), the hypothesized relation between the theoretical model of disgust and BII fears demonstrated good model fit in both samples. Consistent with previous findings on the differential relation between core and animal reminder disgust and BII fears [de Jong, P. J., & Merckelbach H. (1998). Blood-injection-injury phobia and fear of spiders: Domain specific individual differences in disgust sensitivity. Personality and Individual Differences, 24, 153-158], structural equation modeling (SEM) provided support for a domain specific relationship in both samples: animal reminder disgust was specifically related to the BII latent factor, whereas core disgust was not. The clinical and research implications regarding the relationships between disgust and BII fears across cultures are discussed.

The role of cognitions, trait anxiety and disgust sensitivity in generating faintness around blood-injury phobic stimuli

The effects on blood-injury fear and fainting of scripts concerning pain, nausea, and anger and individual differences in trait anxiety and disgust sensitivity were investigated. Eighteen participants were high in disgust sensitivity and trait anxiety, 11 were low in disgust sensitivity but high in trait anxiety, 10 were high in disgust sensitivity but low in trait anxiety, and 16 were low in disgust sensitivity and trait anxiety. Participants were exposed to pain, nausea, and anger scripts during presentation of blood-injury slides. The ability of the scripts to increase symptoms of fear and faintness, on a state version of the Blood-Injection Symptom Scale (BISS; Page, A. C., Bennett, K. S., Carter, O., Smith, J., & Woodmore, K. (1997). Blood-Injection Symptom Scale (BISS): Assessing the structure of phobic symptomatology elicited by blood and injections. Behaviour Research and Therapy, 35, 457-464) were examined. Analyses indicated that individual differences in trait anxiety and disgust sensitivity interact to generate symptoms of faintness when the pain script was read. That is, disgust sensitive and trait anxious participants reported greater faintness relative to other conditions. The implications for theory and treatment of blood-injury-injection phobia are discussed.

The structure of disgust: domain specificity in relation to contamination ideation and excessive washing

The primary goal of the present study was to employ confirmatory factor analysis to compare two theoretical models regarding the factor structure of disgust (N=307). The two-factor model of Animal Reminder and Core disgust proposed by Rozin et al. (2000) demonstrated superior model fit over a one-factor model that has been implicated in prior research. However, contrary to theoretical predictions, categorizing Hygiene disgust as Core disgust rather than Animal Reminder disgust provided an overall better fit for the two-factor model. The second aim of the study was to investigate the relationship between the empirically derived two-factor model and contamination ideation and excessive washing using structural equation modeling. Findings indicated that the Contamination Ideation and Excessive Washing latent factor was specifically related to Core disgust (domain specific) and negatively related to Animal Reminder disgust. The relevance of these findings in the context of future research investigating the role of disgust in specific anxiety disorders is discussed.

End-tidal pCO2 in blood phobics during viewing of emotion- and disease-related films

OBJECTIVE

Many patients with blood, injection, and injury (BII) phobia respond to specific stimuli with vasovagal dysregulation and fainting. However, little is known about the role of hyperventilation in the distress of these patients. Hyperventilation, defined by subnormal arterial pCO2 levels, induces anxiety and may promote the development of fainting. We studied end-tidal pCO2 in 12 patients with BII phobia and 14 nonanxious controls during presentation of emotional films.

METHOD

Ten film clips were shown, two in each of 5 categories: pleasant, unpleasant, neutral, BII-related (surgery), and asthma-related (portraying labored breathing). For each subject, two subsets were created, each containing one clip from each category. For one subset, the instruction was simply to view the film, and for the other subset, to view the film while tensing the leg muscles. PCO2, heart rate, blood pressure, and leg electromyogram were recorded continuously during viewing, and self-report of symptoms and emotion was collected after each film.

RESULTS

Patients reported the greatest anxiety and disgust during surgery films. PCO2 was relatively stable throughout all categories except surgery films, during which minima were below 30 mm Hg, indicating significant hypocapnia. Cardiovascular variables suggested biphasic patterns in two patients with BII phobia. These patients, together with one additional patient and one control who were close to fainting after or during one surgery film, also showed a marked fall in pCO2) Leg muscle tension raised heart rate and systolic blood pressure for all films, but was not related to near-fainting or endurance in surgery film viewing.

CONCLUSION

Hyperventilation is part of the fear response of patients with BII phobia, but was transitory in experimental fear induction using surgery films. Its role in real-life exposure and fainting deserves further study.