Randomized trial on the effects of an EMDR intervention on traumatic and obsessive symptoms during the COVID-19 quarantine: a psychometric study.

Introduction: It has been suggested that the COVID-19 pandemic was a potentially traumatic occurrence that may have induced generalized anxiety and discomfort, particularly in susceptible populations like individuals with mental illnesses. The therapeutic approach known as eye movement desensitization and reprocessing (EMDR) has been shown to be successful in helping patients process traumatic events and restore wellbeing. Nevertheless, little is known about the precise processes through which EMDR fosters symptom recovery. Methods: In order to disentangle these issues, we conducted a randomized controlled trial (ClinicalTrials.gov Identifier NCT06110702) with 107 participants who were selected from university hospitals as a sample of investigation. Random assignments were applied to the participants in order to assign them to the experimental and control groups. The experimental group, but not the control group, underwent an 8-week EMDR intervention. Body perception, disgust, and emotions of guilt and shame, as well as mental contamination and posttraumatic and obsessive-compulsive symptoms, were investigated before and after the EMDR intervention. Results: The EMDR intervention was able to improve all of the variables investigated. Path analysis showed that body perception was able to predict both disgust and emotions of guilt and shame. Disgust was able to predict both mental contamination and obsessive-compulsive symptoms, while guilt and shame were able to predict post-traumatic symptoms. Conclusions: EMDR is an effective therapy for the treatment of post-traumatic and obsessive symptoms that acts through the promotion of improvement of the emotions of guilt/shame and disgust, respectively. Implications for clinical practice are examined. Clinical trial registration: https://www.clinicaltrials.gov, identifier NCT06110702.

Italian validation of the body odor disgust scale.

Introduction: Disgust sensitivity to body odors plays a role in a set of psychological mechanisms supposedly evolved to avoid pathogens. To assess individual differences in body odor disgust, we previously developed the body odor disgust scale (BODS) and validated it in English. The BODS presents six scenarios where disgust could be evoked by smells coming from an internal source and an external source. The present study aimed to validate the BODS in the Italian population and to find further evidence for its structural, construct, and criterion validity. Methods: We used two large samples (N = 1,050, F = 527; and N = 402, F = 203, respectively) that were representative of the Italian population for sex and age. Results: Across these two studies, we confirmed the hypothesized bifactor structure, with all the items loading onto a general body odor disgust sensitivity factor, and on two specific factors related to the internal structure. In terms of construct validity, we found that the BODS converged with pathogen disgust sensitivity of the three-domain disgust scale (TDDS) but was distinct from a general propensity to experience negative emotions. The BODS showed criterion validity in predicting the behavioral intentions toward COVID-19 avoidance behavior, although it did not seem to be incrementally valid when compared to the TDDS pathogen subscale. We also established scalar measurement invariance of the BODS regarding gender and found that women display higher levels of BODS. Discussion: Results from the Italian version of the BODS indicate its structural, construct, nomological and criterion validity. Furthermore, our result on sex differences in disgust sensitivity are consistent with previous literature, and we discuss them in the broader context of cross-cultural and primate findings that points toward a possible evolutionary explanation of this difference.

Association between Disgust Sensitivity during Pregnancy and Endogenous Steroids: A Longitudinal Study.

The emotion of disgust protects individuals against pathogens, and it has been found to be elevated during pregnancy. Physiological mechanisms discussed in relation to these changes include immune markers and progesterone levels. This study aimed to assess the association between steroids and disgust sensitivity in pregnancy. Using a prospective longitudinal design, we analyzed blood serum steroid concentrations and measured disgust sensitivity via text-based questionnaires in a sample of 179 pregnant women during their first and third trimesters. We found positive correlations between disgust sensitivity and the levels of C19 steroids (including testosterone) and its precursors in the Δ5 pathway (androstenediol, DHEA, and their sulfates) and the Δ4 pathway (androstenedione). Additionally, positive correlations were observed with 5α/ß-reduced C19 steroid metabolites in both trimesters. In the first trimester, disgust sensitivity was positively associated with 17-hydroxypregnanolone and with some estrogens. In the third trimester, positive associations were observed with cortisol and immunoprotective Δ5 C19 7α/ß-hydroxy-steroids. Our findings show that disgust sensitivity is positively correlated with immunomodulatory steroids, and in the third trimester, with steroids which may be related to potential maternal-anxiety-related symptoms. This study highlights the complex relationship between hormonal changes and disgust sensitivity during pregnancy.

Phase-Transitions in Disgust During Self-Initiated Eating Among Adolescents With Anorexia Nervosa and Related Low-Weight Eating Disorders and Matched Controls.

BACKGROUND: Understanding the emotional context of feeding behavior may help identify causal mechanisms of food avoidance among individuals with anorexia nervosa. Although predominant food avoidance models assume fear of fat drives feeding behavior, disgust may be more theoretically and proximally relevant to moment-to-moment experiences of feeding. This study, therefore, aimed to examine affect and food avoidance using automated affect analysis from facial response by measuring time-specific transitions in disgust during a laboratory eating paradigm. We hypothesized that phase transitions in disgust would distinguish temporally self-initiated eating from food avoidance. METHODS: Sixty-three adolescents with anorexia nervosa or another low-weight eating disorder (LWED) and 27 age- and sex-matched controls were recruited as part of a larger study; 45 patients and 22 controls provided data on autonomous eating and facial affect during a laboratory meal. Dynamic structural equation models quantified moment-to-moment relationships between disgust and feeding behavior. RESULTS: Self-initiated eating was associated with greater increases in disgust, but not fear, intensity among those with LWED relative to control participants and greater disgust intensity predicted lower likelihood of self-initiated eating. DISCUSSION: Phasic transitions in disgust provide moment-to-moment evidence of affective influence on self-initiated eating and lend credibility to the hypothesis that disgust contributes to food avoidance and initiation in individuals with LWED.

People who seem disgusting seem more immoral.

Despite unresolved questions about replicability, a substantial number of studies find that disgust influences and arises from evaluations of immoral behavior and people. Departing from prior emphases, the current research examines a novel, related question: Are people who are viewed as disgusting (i.e., people whose habits seem disgusting) perceived as more immoral than typical or unusual people? Four experiments examined this, also exploring the downstream impacts of moral character judgments. Adults who seemed disgusting were regarded as more immoral for purity and non-purity violations (Experiment 1) and less praiseworthy for prosocial acts (Experiment 2). In Experiment 3, an 8-year-old with typical (but seemingly disgusting) habits was rated as "naughtier" and likelier to misbehave than an atypical child who loved vegetables and disliked sweets. Experiment 4 revealed how, when no behavioral information is available, beliefs about target disgust influence beliefs about future behavior, helping explain why seemingly disgusting targets are viewed as more immoral, but not always more punishable for their bad behavior.

Conceptual-level disgust conditioning in contamination-based obsessive-compulsive disorder.

Pavlovian fear conditioning and extinction represent learning mechanisms underlying exposure-based interventions. While increasing evidence indicates a pivotal role of disgust in the development of contamination-based obsessive-compulsive disorder (C-OCD), dysregulations in conditioned disgust acquisition and maintenance, in particular driven by higher-order conceptual processes, have not been examined. Here, we address this gap by exposing individuals with high (HCC, n = 41) or low (LCC, n = 41) contamination concern to a conceptual-level disgust conditioning and extinction paradigm. Conditioned stimuli (CS+) were images from one conceptual category partially reinforced by unconditioned disgust-eliciting stimuli (US), while images from another category served as non-reinforced conditioned stimuli (CS-). Skin conductance responses (SCRs), US expectancy and CS valence ratings served as primary outcomes to quantify conditioned disgust responses. Relative to LCC, HCC individuals exhibited increased US expectancy and CS+ disgust experience, but comparable SCR levels following disgust acquisition. Despite a decrease in conditioned responses from the acquisition phase to the extinction phase, both groups did not fully extinguish the learned disgust. Importantly, the extinction resilience of acquired disgust was more pronounced in HCC individuals. Together, our findings suggest that individuals with high self-reported contamination concern exhibit increased disgust acquisition and resistance to extinction. The findings provide preliminary evidence on how dysregulated disgust learning mechanism across semantically related concepts may contribute to C-OCD.

Symptoms of premenstrual dysphoric disorder and cycle phase are associated with enhanced facial emotion detection: An online cross-sectional study.

BACKGROUND: Premenstrual dysphoric disorder is a depressive disorder affecting 5%-8% of people with menstrual cycles. Despite evidence that facial emotion detection is altered in depressive disorders, with enhanced detection of negative emotions (negativity bias), minimal research exists on premenstrual dysphoric disorder. OBJECTIVES: The goal of this study was to investigate the effect of premenstrual dysphoric disorder symptoms and the premenstrual phase on accuracy and intensity at detection of facial emotions. DESIGN: Cross-sectional quasi-experimental design. METHOD: The Facial Emotion Detection Task was administered to 72 individuals assigned female at birth with no premenstrual dysphoric disorder (n = 30), and provisional PMDD (n = 42), based on a retrospective Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition-based measure of premenstrual dysphoric disorder. Facial emotion detection was examined both irrespective of menstrual cycle phase, and as a function of premenstrual phase (yes, no). The task used neutral-to-emotional facial expression morphs (15 images/morph). Participants indicated the emotion detected for each image within the progressive intensity morph. For all six basic emotions (sad, angry, fearful, happy, disgust, and surprise), two scores were calculated: accuracy of responses and the intensity within the morph at which the correct emotion was first detected (image number). RESULTS: Individuals reporting moderate/severe symptoms of premenstrual dysphoric disorder had more accurate and earlier detection of disgust, regardless of cycle phase. In addition, those with provisional premenstrual dysphoric disorder detected sad emotions earlier. A premenstrual dysphoric disorder group × cycle phase interaction also emerged: individuals reporting premenstrual dysphoric disorder symptoms were more accurate at detecting facial emotions during the premenstrual phase compared to the rest of the cycle, with a large effect size for sad emotions. CONCLUSION: The findings suggest enhanced facial emotion processing in individuals reporting symptoms of premenstrual dysphoric disorder, particularly for sadness and disgust. However, replication is required with larger samples and prospective designs. This premenstrual dysphoric disorder premenstrual emotion detection advantage suggests an adaptive cognitive mechanism in premenstrual syndrome/premenstrual dysphoric disorder, and challenges stigma surrounding premenstrual experiences.

Women with Severe Premenstrual Syndrome or Probable Premenstrual Dysphoric Disorder are Better at Identifying Emotional Expressions on People's Faces, Especially During the Premenstrual PhasePremenstrual dysphoric disorder is a depressive disorder affecting women where they experience emotional and physical symptoms during the premenstrual phase (i.e. the week before one's period). It is a severe form of premenstrual syndrome. Research indicates that depression can affect facial emotion recognition. Accurately recognizing other people's emotions is an important skill that helps us develop social connections and keep ourselves and others safe. Quick recognition of facial emotions allows us to understand and support others, and quickly identify dangerous situations by recognizing other people's emotional responses. The goal of this study was to examine how premenstrual dysphoric disorder symptoms and the premenstrual phase may affect the ability of women to recognize and identify emotions on other people's faces. A total of 72 women (42 with premenstrual dysphoric disorder, 30 without premenstrual dysphoric disorder) completed the Facial Emotion Detection Task. This task measured how accurate and early the women were able to detect happiness, sadness, anger, fear, surprise, and disgust in faces. Women with moderate/severe symptoms of premenstrual dysphoric disorder had more accurate and earlier detection of disgust, regardless of where they were in their menstrual cycle. Women with premenstrual dysphoric disorder detected sad emotions earlier. Furthermore, women with premenstrual dysphoric disorder were more accurate at detecting facial emotions when they were tested in the premenstrual phase, and were especially more accurate in detecting sad emotions. The findings suggest that women with premenstrual dysphoric disorder are better at detecting facial emotions and show a premenstrual dysphoric disorder premenstrual emotion detection advantage. This tendency for women with premenstrual dysphoric disorder to better detect emotions in others, particularly when they are in the premenstrual cycle phase, would have benefits. As one of the first reports of a potentially beneficial effect of premenstrual syndrome for women, the findings may help decrease stigma associated with premenstrual dysphoric disorder and premenstrual syndrome. Further research is needed to replicate and extend these findings.

Electrophysiological Correlates of Amplified Emotion-Related Cognitive Processing Evoked by Self-Administered Disgust Images.

In the processing of emotions, the brain prepares and reacts in distinctive manners depending upon the negative or positive nuance of the emotion elicitors. Previous investigations showed that negative elicitors generally evoke more intense neural activities than positive and neutral ones, as reflected in the augmented amplitude of all sub-components of the event-related potentials (ERP) late posterior positivity (LPP) complex, while less is known about the emotion of disgust. The present study aimed to examine whether the LPP complex during the processing of disgust stimuli showed greater amplitude than other emotion elicitors with negative or positive valences, thus confirming it as a neural marker of disgust-related negativity bias at earlier or later stages. Thus, in the present study, we leveraged the ERP technique during the execution of an affective self-administered visual stimuli task to disentangle the neural contributions associated with images of positive, negative, disgust, or neutral emotions. Crucially, we showed that handling with disgust elicitors prompted the greatest neural activity and the highest delay during self-administration. Overall, we demonstrated progressive neural activities associated with the unpleasantness of the emotion elicitors and peculiar processing for disgust compared with all other emotions.

Infection risk associated with carnivore carcasses may govern trophic interactions between maggots and insectivorous passerine birds.

Infection risk by pathogenic agents motivates hosts to avoid using resources with high risks. This, in turn, results in increased availability of these resources for other species that are more tolerant of infections. For instance, carcasses of mammalian carnivores are frequently avoided by conspecific or closely related carnivores, allowing them to be almost exclusively used by maggots. This may lead to novel interactions with other species. This study investigated the consumption of maggots from carnivore carcasses by non-corvid passerines. We successfully monitored 66 raccoon carcasses in Hokkaido, Japan, from 2016 to 2019. Vertebrates only scavenged 14 carcasses before maggot dispersal; the other 52 carcasses produced abundant maggots that regularly fed at least 12 species of non-corvid passerines. Surprisingly, predation occurred at a distance from the carcasses, mainly after maggot dispersal for pupation, despite the higher efficiency of feeding on maggot masses on the carcasses. Birds are likely to reduce the potential risk of infection from the carcass and/or from maggots on the carcasses. Overall, only 1% of maggots were consumed. Our results suggest that necrophagous flies could benefit from the infection risk associated with carnivore carcasses, which may decrease scavenging by other carnivores and constrain maggot consumption by insectivorous birds.

Virtual Reality Exposure Therapy for Treating Fear of Contamination Disorders: A Systematic Review of Healthy and Clinical Populations.

Virtual Reality Exposure Therapy (VRET), particularly immersive Virtual Reality Exposure Therapy (iVRET), has gained attraction as an innovative approach in exposure therapy (ET), notably for some anxiety disorders with a fear of contamination component, such as spider phobia (SP) and obsessive-compulsive disorder (OCD). This systematic work investigates iVRET's effectiveness in modulating disgust emotion-a shared aberrant feature across these disorders. Recent reviews have evaluated VRET's efficacy against in vivo ET. However, emerging evidence also highlights iVRET's potential in diminishing atypical disgust and related avoidance behaviors, expanding beyond traditional fear-focused outcomes. Our systematic synthesis, adhering to PRISMA guidelines, aims to fill this gap by assessing iVRET's efficacy in regulating disgust emotion within both clinical and at-risk populations, identified through standardized questionnaires and subjective disgust ratings. This research analyzes data from eight studies on clinical populations and five on healthy populations, offering an insight into iVRET's potential to mitigate the aberrant disgust response, a common transdiagnostic feature in varied psychopathologies. The findings support iVRET's clinical relevance in disgust management, providing evidence for a broader therapeutic application of iVRET and pointing out the need for more focused and complete investigations in this emergent field.

Edible Insects in Slavic Culture: Between Tradition and Disgust.

Insects are a conventional food in many cultures worldwide. Why therefore are they treated with aversion by the majority of people in Western countries? The aim of this work is to understand cultural norms and historical practices related to insects that can explain why in the countries of the West it is so difficult to accept them as a foodstuff, and why the disgust that they arouse is more common than in other regions of the world. Insects in Western countries are associated with negative experiences resulting from cultural and religious beliefs, traditions, stories, myths and individual experiences. Although there are species of insect that have positive associations, the high number of negative terms popularized the negative image of these creatures in people's minds, as a result of which the concept of insects as a foodstuff arouses disgust in the culture of the West. Understanding the aversion to insects will contribute to the broader understanding of consumer attitudes, cultural influences on consumption, or potential shifts in food choices. It also can help develop strategies or methods that will assist in changing this reluctance and encourage the utilization of insects as a food source.

The experiences of individuals with body dysmorphic disorder: A systematic review and thematic synthesis of qualitative research.

Body Dysmorphic Disorder (BDD) is a distressing psychological condition where an individual is preoccupied by a perceived issue with their appearance. Qualitative studies enable nuanced aspects of BDD phenomenology to be investigated. The current systematic review used thematic synthesis to integrate the findings from the extant qualitative studies. Searches were run on six databases to identify studies that had sought to describe the experience of individuals with BDD. PRISMA guidance was followed and ten articles were identified for inclusion. The quality of each article was appraised and thematic synthesis was conducted to generate novel and summative themes. Three superordinate themes were created: 'self-objectification and the view of self'; 'control and protecting the self'; and 'sociocultural influences and the impact of others in BDD'. Shame and self-disgust emerged as key experiential elements of BDD. The findings of the review suggest that self-objectification theory and possibly models of self-compassion are theoretically relevant to understanding the experience of individuals presenting with BDD. Current interventions may benefit from consideration of these theoretical models when seeking to improve efficacy.

Introduction to the special issue: evolutionary and biopsychosocial perspectives on sickness communication.

Here, we introduce the EMPH special issue on Evolutionary and Biopsychosocial Perspectives on Sickness Communication. This Commentary provides an overview of each article and places them in the wider context of sickness as a social phenomenon with verbal and nonverbal signals. This Commentary, and the special issue, in general, calls for greater attention to these signals that can affect pathogen transmission and may be at the evolutionary root of our caregiving systems and behaviours.

Ghosts of parasites past influence current non-consumptive effects in Drosophila nigrospiracula.

Parasites can indirectly impact hosts through non-consumptive effects (NCEs) via changes in behaviour, morphology, and/or physiology. These responses can be understood in terms of the ecology of fear (ectoparasites) or the ecology of disgust (endoparasites) framework. We tested the hypothesis that NCEs of parasite exposure (e.g., parasite avoidance and defense) trade off with other important behaviours such as feeding and resting. We predicted that when exposed to parasites (without infection), hosts will increase their defensive behaviors at the expense of feeding. We also posited that history of exposure (without infection), or previous infection would impact the expression of these NCEs. The study system involves a cactophilic fruit fly (Drosophila nigrospiracula) and a naturally occurring parasitic mite (Macrocheles subbadius). First, we assessed how prior mite exposure affected fly behaviour in response to current parasite exposure. Mite presence resulted in increased grooming and movement, but exposure history did not affect these behaviours. However, the interaction between previous and current exposure influenced host feeding and resting behaviours. We found that previously exposed flies increased feeding and decreased resting upon a secondary mite exposure. In a second experiment, we tested the role of infection history on current parasite exposure. Compared with naïve flies, previously infected flies were expected to increase defensive behaviours upon secondary exposure. Flies increased defensive and ambulatory behaviour in the presence of mites, and consequently less time was spent resting but feeding was unaffected. None of the behaviours measured were affected by previous infection status. In general, current parasite exposure resulted in NCEs. Moreover, our results showed that previous exposure (without infection) to parasites may have an even stronger effect upon secondary exposure than infection history. Our study highlights the importance of the ecology of fear and the role that exposure and infection history plays in generating NCEs of parasitism.

Facing the Emotional Barriers to Colorectal Cancer Screening. The Roles of Reappraisal and Situation Selection.

BACKGROUND: Disgust, embarrassment, and fear can hinder the attendance of colorectal cancer (CRC) screening. However, individuals can respond to these emotions differently. The present study tested whether reappraising a negative stimulus versus avoiding a negative stimulus is associated with age; whether these two emotion regulation strategies (reappraisal and situation selection) moderate the effects of disgust, embarrassment and fear on CRC screening intention; and the efficacy of a message based on participants' preferred emotion regulation strategy. METHODS: We recruited 483 Italian participants (aged 40-84 years) through snowball sampling. Participants were randomly assigned to one of four conditions differing for a message promoting CRC screening with an affective lever, a cognitive lever, both levers or none. Key variables included emotion regulation strategies, emotional barriers and intention to get screened. RESULTS: The preference for reappraisal over situation selection increased with age. Reappraisal neutralized the effect of disgust on CRC screening intention. The combined message with both affective and cognitive levers increased CRC screening intention (b = 0.27, ß = 0.11, SE = 0.13 p = .049), whereas reading the message based only on the affective (b = 0.16, ß = 0.06, SE = 0.14 p = .258) or the cognitive (b = 0.22, ß = 0.09, SE = 0.14 p = .107) lever was not effective. CONCLUSIONS: Communication campaigns should support the activation of a reappraisal strategy of emotion control, and messages promoting CRC screening should highlight both the instrumental (i.e., early detection) and affective (i.e., peace of mind) benefits of attendance.

Contamination-Focussed Vignettes as an Analogue of Infectious Pandemics: An Experimental Validation using the State Disgust and Anxiety Responses in OCD.

Despite infectious pandemics proving particularly detrimental to those with Obsessive-Compulsive Disorder (OCD), the investigation of analogous experimental paradigms is lacking. To address this gap, we conducted two studies employing vignettes that depicted contamination-related situations commonly experienced during a pandemic (e.g., Coughing into hands and failing to use hand sanitizer). We manipulated the salience of these vignettes across three levels: high contamination, low contamination, and a neutral control condition. Our examination of state anxiety and disgust responses in all participants revealed the successful manipulation of the vignettes' impact. Specifically, individuals with more severe OCD symptoms reported significantly higher levels of state disgust and anxiety for both high and low contamination vignettes, in contrast to the group with lower symptom severity. No significant differences were observed in the neutral vignette condition between the high- and low-scoring groups. Interestingly, for those with higher OCD symptoms, high salience contamination-focused vignettes resulted in similarly elevated state disgust and anxiety, regardless of whether the vignettes were situated in public (Study 1) or domestic (Study 2) settings. This suggests that the heightened sensitivity to contamination-related scenarios observed in individuals with OCD symptoms in the present study is not confined to a specific context. These findings support the use of contamination-focused vignettes as analogues for studying infectious pandemics and provide valuable insights into OCD models, interventions, and future research.

Disgust as a basic, sexual, and moral emotion.

Disgust is a basic emotion that increases the organism's survival success by preventing the transfer of pathogens. In this regard, it directs cognitive processes and motivates avoidance behaviors that prevent pathogens from entering the body. Moreover, disgust has many specific characteristics that distinguish it from other basic emotions. Firstly, unlike other basic emotions, it contaminates neutral objects around it and causes difficult-to-change learning. Another specific characteristic of disgust is that it depends on ideational processes. Objects, situations, and behaviors that do not contain pathogens can also cause disgust. In this regard, disgust appears not only as a basic emotion but also as different adaptations in different fields. In this context, two distinct adaptations of disgust stand out: sexual and moral disgust. These two adaptations of disgust benefit from disgust-related behaviors and motivations in different ways. Sexual disgust works as a gene protection mechanism, while moral disgust helps maintain social rules. The specific characteristics of disgust and its effects on cognitive processes such as attention and memory interact. In conclusion, the multifaceted structure of disgust shows that it needs to be studied more in the subfields of psychology. (Strohminger, Philos Compass 9:478-493, 2014) defines disgust as a psychological nebula that needs to be discovered. However, it is observed that disgust has not been adequately addressed. This review aims to comprehensively explore unique characteristics and diverse aspects of disgust, shedding light on its significance from various perspectives. This study underscores the broader understanding of disgust and its pivotal role in psychological research.