Cognitive and psychophysiological correlates of disgust in obsessive-compulsive disorder

Comparison between Physical Activity and Stress-Related Lifestyle between Orthorexic and Non-Orthorexic University Students: A Case-Control Study

(1) Background: The literature regarding orthorexia nervosa (ON) has well documented the association with other mental disorders, such as obsessive-compulsive and eating disorders. However, the research has not taken into account stress-related behavior and the conduction of physical activity (PA), both structured and unstructured. (2) Methods: In this cross-sectional study, 165 students of the University of Parma (92 females and 74 males) aged between 18 and 49 years old (mean = 24.62 ± 4.81) were consecutively recruited. The ORTO-15 questionnaire was used to divide the total sample into a group without orthorexia (score > 40) and a group with orthorexia (score < 40). All subjects completed the P Stress Questionnaire, and specific items were extrapolated from the Eating Habits Structured Interview (EHSI) to investigate lifestyle, including structured and unstructured PA. (3) Results: Subjects with orthorexia represented 83% of the total sample and reported higher levels of stress-related risk behaviors (i.e., sense of responsibility (t = -1.99, p = 0.02), precision (t = -1.99, p = 0.03), stress disorders (t = -1.38, p = 0.05), reduced spare time (t = -1.97, p = 0.03), and hyperactivity (t = -1.68, p = 0.04)) and a higher frequency of PA (i.e., hours spent training in structured PA, daily (t = -1.68, p = 0.05), weekly (t = -1.91, p = 0.03), and monthly (t = -1.91, p = 0.03), the tendency to carry out physical exercise even if tired (t = -1.97, p = 0.02), and to adhere to unstructured PA (i.e., moving on foot or by bike rather than using transport (t = 1.27, p = 0.04)). (4) Conclusions: The results confirmed the presence of hyperactivity at a motor and behavioral level in people with orthorexia. Further studies are necessary to highlight the causality between ON, stress, and physical activity but it may be possible to hypothesize that "obsessive" physical exercise may not generate the benefits generally known by the literature.

Can immorality be contracted? Appraisals of moral disgust and contamination fear

While extant research underlines the role of disgust in obsessive-compulsive disorder (OCD) with contamination fear, less research attention has been devoted to moral disgust. This study endeavored to examine the types of appraisals that are elicited by moral disgust in comparison to core disgust, and to examine their associations with both contact and mental contamination symptoms. In a within-participants design, 148 undergraduate students were exposed to core disgust, moral disgust, and anxiety control elicitors via vignettes, and provided appraisal ratings of sympathetic magic, thought-action fusion and mental contamination, as well as compulsive urges. Measures of both contact and mental contamination symptoms were administered. Mixed modeling analyses indicated that core disgust and moral disgust elicitors both provoked greater appraisals of sympathetic magic and compulsive urges than anxiety control elicitors. Further, moral disgust elicitors elicited greater thought-action fusion and mental contamination appraisals than all other elicitors. Overall, these effects were greater in those with higher contamination fear. This study demonstrates how a range of contagion beliefs are evoked by the presence of 'moral contaminants', and that such beliefs are positively associated with contamination concerns. These results shed light on moral disgust as an important target in the treatment of contamination fear.

A Systematic Review of Clinical Psychophysiology of Obsessive-Compulsive Disorders: Does the Obsession with Diet Also Alter the Autonomic Imbalance of Orthorexic Patients?

(1) Background: A new mental illness is attracting the attention of researchers and mental health professionals. Orthorexia nervosa (ON) is a possible new mental disorder, the main symptom of which is an obsessive and insecure focus on healthy foods and consequent compulsive behaviors. There is a common consensus among researchers that ON is considered partly overlapping with obsessive-compulsive disorders (OCDs). (2) Methods: MEDLINE and Scopus were searched for articles published in the last 10 years regarding the psychophysiological aspects of OCD and ON. Eight studies met the eligibility criteria. The inclusion criteria encompassed adults diagnosed with OCD and/or ON. However, only studies involving OCD patients were found. (3) Results: Some research groups have shown that OCD disorders can be considered among anxiety disorders because they are characterized by anxious hyper activation. Other research, however, has shown profiles characterized by low psychophysiological reactivity to stressful stimuli. Despite this, there seems to be a consensus on the poor inhibition abilities, even when activation is low, and the dissociation between cognitive and psychophysiological activation emerged. (4) Conclusions: However discordant, some points seem to bring the researchers to agreement. In fact, there is consensus on conducting a multidimensional assessment that can measure all of the aspects of suffering (cognition, emotion, and behavior) and highlight the poor body-mind integration. This clinical approach would make it possible to propose interventions aimed at treating some mental illnesses such as food obsession that can paradoxically impair the psychophysical balance. Nevertheless, the applied systematizing approach to existing studies on ON is very much needed for better understanding of the psychophysical nature of this new mental illness and its implications for prevention and treatment.

Exposure and Response Prevention in Virtual Reality for Patients with Contamination-Related Obsessive-Compulsive Disorder: a Case Series

Exposure therapy in virtual reality is successful in treating anxiety disorders. Studies on exposure and response prevention in virtual reality (VERP) in obsessive-compulsive disorder (OCD) are rare, and it is unclear whether distress associated with other emotions than anxiety (e.g., disgust) can be evoked. The present study aimed to investigate whether distress can be induced during VERP in patients with contamination-related OCD (C-OCD) and a primary feeling of disgust. We treated eight female patients with C-OCD with the primary emotion of disgust over six weeks with VERP and assessed their OC symptoms before and after the intervention period with the Y-BOCS. We measured subjective units of distress (SUD), heart rate and skin conductivity (arousal), sense of presence, and simulator sickness during four consecutive exposure sessions. VERP was able to induce distress and arousal. The qualitative feedback was heterogeneous and sense of presence moderate. Patients' OC symptoms reduced over the treatment period with medium to large effect sizes, but only two patients were considered responders; two patients discontinued treatment due to lack of treatment success. Although VERP was able to induce distress and arousal associated with disgust and evoked a moderate sense of presence, the low rate of symptom reduction diminishes the positive results. Possible reasons for the heterogeneous results and implications are discussed. Trial registration: German Registry for Clinical Studies (DRKS00016929), 10.04.2019.

The Role of Disgust in Eating Disorders

PURPOSE OF REVIEW

In current review, we evaluate the current literature examining the role of disgust in eating disorders (EDs), and provide a theoretical model designed to inform the study and treatment of disgust-based symptoms in EDs.

RECENT FINDINGS

Findings from this review suggest that aberrant disgust-conditioning processes represent promising but understudied mechanisms that may contribute to the risk and maintenance of core eating disorder (ED) psychopathology. In addition, preliminary evidence supports the use of interventions designed to target aversive disgust cues and disrupt maladaptive disgust-based conditioning that may maintain eating pathology. However, experimental studies designed to elucidate the role of disgust and aversive learning processes remain limited. Disgust is a promising risk and maintenance factor in EDs. Future systematic investigation is needed to examine disgust-based processes at a mechanistic level in order to better understand the links between disgust, avoidance behaviors, and EDs. Further investigation of the mechanistic role of disgust in EDs is warranted.

Presenting new stimuli to study emotion: Development and validation of the Objects-on-Hands Picture Database

A long-standing goal shared by researchers has been to design optimal experimental procedures, including the selection of appropriate stimuli. Pictures are commonly used in different research fields. However, until recently, researchers have relied mostly on line-drawings, which can have poor ecological validity. We developed a set of high quality standardized photographs of objects from six different categories, recorded under two camera viewpoints, and five presentation conditions (on its own, held by clean hands, and by hands covered with different substances: sauce, chocolate and mud). These various staging conditions can be used to induce different emotional states while maintaining the object of interest constant. We first report normative data on the objects’ name agreement and familiarity collected from North American and Portuguese participants. Results showed high name agreement and familiarity in both samples. Next, arousal, disgust and valence ratings were collected for the stimuli under either an emotional-activating or a neutral context. Subjective ratings varied according to the staging condition and the context, confirming that the same items can effectively be used in different emotional conditions. This database allows researchers to select more ecologically-valid stimuli according to their research purposes while considering several variables of interest and avoiding item-selection problems commonly present when comparing responses to neutral and emotional items.

Erroneously Disgusted: fMRI Study Supports Disgust-Related Neural Reuse in Obsessive-Compulsive Disorder (OCD)

Objective: fMRI scans of patients with obsessive-compulsive disorder (OCD) consistently show a hyperactivity of the insular cortex, a region responsible for disgust-processing, when confronted with symptom-triggering stimuli. This asks for an investigation of the role of disgust and the insula in OCD patients.

Methods: Seventeen inpatients with OCD and 17 healthy controls (HC) underwent fMRI scanning. Whole-brain contrasts were calculated for “Disgust vs. Neutral” for both groups, plus an analysis of variance (ANOVA) to assess the interaction between group and condition. Additionally, the emotional dimensions of valence and arousal, along with the ability to cope, were assessed by picture ratings.

Results: The picture ratings confirmed the patients’ heightened sensitivity to disgust with higher values for arousal and inability to cope, but not for valence. fMRI scans revealed no hyperactivity of the insula in patients compared to controls for the condition “Disgust vs. Neutral,” indicating no basic hypersensitivity to disgusting stimuli. Increased activity in the precuneus in controls for this condition might correspond to the downregulation of arousal.

Conclusions: The absent differences in neural activity of the insula in patients compared to controls for the disgust-condition, but heightened activity for symptom-provoking conditions, suggests that the illness is due to an erroneous recruitment of the insula cortex for OCD-stimuli. The finding is interpreted within the framework of the neural reuse hypothesis.

Disgust in Anxiety and Obsessive-Compulsive Disorders: Recent Findings and Future Directions

PURPOSE OF REVIEW

In the past 20 years, the role of disgust in anxiety disorders and obsessive-compulsive disorder (OCD) has been investigated with increasing precision. In this review, we examine recent evidence implicating disgust in anxiety and OCD, highlighting recent measurement and methodological improvements. Specific emphasis is placed on understanding the mechanisms that may account for the role of disgust in OCD and related disorders.

RECENT FINDINGS

Recent developments include clarification of the role of distinct disgust-relevant vulnerabilities in the etiology of anxiety and OCD, an improved understanding of the neurobiology of disgust processing in OCD, and an increased focus on disgust-related mechanisms that contribute to psychopathology, such as disgust-based learning and emotion regulation. Disgust proneness is increasingly linked with symptoms of anxiety and OCD. However, further examination of the mechanisms that account for the roles of distinct disgust-relevant vulnerabilities is needed, and studies that directly examine disgust during the course of treatment are limited. Increasingly, the field has moved toward experimental investigation of specific disgust-relevant mechanisms that influence the etiology and treatment of OCD and related anxiety disorders.

OCD: obsessive-compulsive … disgust? The role of disgust in obsessive-compulsive disorder

Recent research has identified the important role of disgust in the symptomatology of obsessive-compulsive disorder (OCD). Exaggerated and inappropriate disgust reactions may drive some of the symptoms of OCD, and in some cases, may even eclipse feelings of anxiety. This paper reviews behavioural and neuroimaging research that recognizes the prominent role of disgust in contributing to OCD symptoms, especially contamination-based symptoms. We discuss how elevated behavioural and biological markers of disgust reported in OCD populations support the need for alternative clinical treatment strategies and theoretical models of OCD.

Obsessive compulsive and related disorders: comparing DSM-5 and ICD-11

Obsessive-compulsive disorder (OCD) has been recognized as mainly characterized by compulsivity rather than anxiety and, therefore, was removed from the anxiety disorders chapter and given its own in both the American Psychiatric Association (APA) Diagnostic and Statistical Manual of Mental Disorders (DSM-5) and the Beta Draft Version of the 11th revision of the World Health Organization (WHO) International Classification of Diseases (ICD-11). This revised clustering is based on increasing evidence of common affected neurocircuits between disorders, differently from previous classification systems based on interrater agreement. In this article, we focus on the classification of obsessive-compulsive and related disorders (OCRDs), examining the differences in approach adopted by these 2 nosological systems, with particular attention to the proposed changes in the forthcoming ICD-11. At this stage, notable differences in the ICD classification are emerging from the previous revision, apparently converging toward a reformulation of OCRDs that is closer to the DSM-5.

Cognitive and emotional impairments in obsessive-compulsive disorder: Evidence from functional brain alterations

There is a common agreement on the existence of dysfunctional cortico-striatal-thalamus-cortical pathways in OCD. Despite this consensus, recent studies showed that brain regions other than the CSTC loops are needed to understand the complexity and diversity of cognitive and emotional deficits in OCD. This review presents examples of research using functional neuroimaging, reporting abnormal brain processes in OCD that may underlie specific cognitive/executive (inhibitory control, cognitive flexibility, working memory), and emotional impairments (fear/defensive, disgust, guilt, shame). Studies during resting state conditions show that OCD patients have alterations in connectivity not only within the CSTC pathways but also in more extended resting state networks, particularly the default mode network and the fronto-parietal network. Additionally, abnormalities in brain functioning have been found in several cognitive and emotionally task conditions, namely: inhibitory control (e.g., CSTC loops, fronto-parietal networks, anterior cingulate); cognitive flexibility (e.g., CSTC loops, extended temporal, parietal, and occipital regions); working memory (e.g., CSTC loops, frontal parietal networks, dorsal anterior cingulate); fear/defensive (e.g., amygdala, additional brain regions associated with perceptual - parietal, occipital - and higher level cognitive processing - prefrontal, temporal); disgust (e.g., insula); shame (e.g., decrease activity in middle frontal gyrus and increase in frontal, limbic, temporal regions); and guilt (e.g., decrease activity anterior cingulate and increase in frontal, limbic, temporal regions). These findings may contribute to the understanding of OCD as both an emotional (i.e., anxiety) and cognitive (i.e., executive control) disorder.

Changes in disgust and heart rate during exposure for Obsessive Compulsive Disorder: A case series

BACKGROUND AND OBJECTIVES

The emotion of disgust has been suggested as a factor contributing to a poor response to Cognitive Behaviour Therapy (CBT) in the treatment of Obsessive Compulsive Disorder (OCD). However, only limited information is available about the phenomenology of disgust in clinical OCD and the physiological mechanisms involved. This case series was designed to explore the phenomenology of OCD and the physiological activity associated with the emotion of disgust.

METHODS

State disgust and heart rate was measured in eleven participants attending treatment for OCD during exposure relevant to their individual formulation.

RESULTS

All participants with contamination and most patients with blood and injury related fears experienced a prominent increase in state disgust during exposure. These participants also had absent heart rate acceleration during exposure. Disgust response correlated with heart rate response (r = -0.63, p < 0.01) and Root Mean Square of Successive Differences (RMSSD) (r = 0.52, p < 0.01).

LIMITATIONS

The design using ecologically valid stimuli and the limited number of participants did not allow between subject comparisons or more detailed analysis of relationship between trait and state disgust and between disgust and severity of OCD.

CONCLUSIONS

Our findings show that a large proportion of our case series with OCD experience prominent disgust with signs of increased vagal tonus during their exposure. Such experiences differ from the concept of adrenergic activation used for psychoeducation in CBT and appraisals of harm and this may result in poorer therapeutic outcome.

Two systems for empathy in obsessive-compulsive disorder: mentalizing and experience sharing

Objective:

To investigate empathic abilities in patients with obsessive-compulsive disorder (OCD) compared to control subjects. OCD is characterized by persistent obsessions and compulsions. Previous studies have proposed specific emotion recognition deficits in patients with OCD. The ability to recognize emotion is part of the broad construct of empathy that incorporates mentalizing and experience-sharing dimensions.

Methods:

Twenty-four subjects with a diagnosis of OCD and 23 control subjects underwent empathic measures.

Results:

Patients with OCD compared to control subjects showed deficits in all mentalizing measures. They were incapable of understanding the mental and emotional states of other people. On the other hand, in the sharing experience measures, the OCD group was able to empathize with the emotional experience of other people when they expressed emotions with positive valence, but were not able to do when the emotional valence was negative.

Conclusion:

Our results suggest that patients with OCD show a difficulty in mentalizing ability, whereas the deficit in sharing ability is specific for the negative emotional valence.