Extinction in multiple contexts reduces the return of extinguished responses: A multilevel meta-analysis

Extinguished responses have been shown to reappear under several circumstances, and this reappearance is considered to model behaviors such as relapse after exposure therapy. Conducting extinction in multiple contexts has been explored as a technique to decrease the recovery of extinguished responses. The present meta-analysis aimed to examine whether extinction in multiple contexts can consistently reduce the recovery of extinguished responses. After searching in several databases, experiments were included in the analysis if they presented extinction in multiple contexts, an experimental design, and an adequate statistical report. Cohen's d was obtained for each critical comparison and weighted to obtain the sample's average weighted effect size. Analyses were then performed using a multilevel meta-analytic approach. Twenty-five studies were included, with a total sample of 37 experiments or critical comparisons. The analyses showed a large effect size for the sample, moderated by the length of conditioned stimulus exposure, type of experimental subject, and type of recovery. The robust effect of extinction in multiple contexts on relapse should encourage clinicians to consider extinction in multiple contexts as a useful technique in therapy and research.

Is disgust more resistant to extinction than fear? A meta-analytic review of laboratory paradigms

Disgust can be acquired via evaluative conditioning; a process by which a neutral stimulus (conditioned stimulus; CS) comes to be evaluated as disgusting due to its pairing with an inherently disgusting stimulus (unconditioned stimulus; US). Research has shown that conditioned disgust responses are resistant to extinction which may have implications for disorders (i.e., contamination-based obsessive-compulsive disorder, specific phobias, and post-traumatic stress disorder) in which heightened disgust has been implicated. Importantly, extinction is the primary mechanism by which exposure therapies are thought to achieve symptom reduction for these disorders. Exposure therapies were originally modeled on fear extinction, whereas disgust extinction was largely overlooked until recently. Accordingly, differences in the degree to which learned disgust and fear can be attenuated via extinction learning remains unclear. The present investigation was a meta-analysis directly comparing the degree of extinction of conditioned disgust (n = 14) and conditioned fear (n = 14) in laboratory paradigms. Extinction was operationalized as the standardized mean difference (SMD) in evaluative ratings between the CS+ (the CS paired with the US) and CS- (the unpaired CS) after extinction training. Results of a subgroup analysis indicated that disgust (SMD = 0.52) was significantly more resistant to extinction than fear (SMD = 0.37). Additionally, a series of meta-regression analyses indicated that extinction was not influenced by important study characteristics (e.g., sex, age, number of conditioning and extinction trials). The findings suggest that extinction-based approaches may be less effective at attenuating learned disgust and research is needed to better optimize treatments for disgust-related disorders.

Treatment of disgust in specific emotional disorders

Although conditioning approaches have highlighted potential characteristics of disgust in anxiety disorders, obsessive-compulsive disorder (OCD), and posttraumatic stress disorder (PTSD), these findings have yet to be translated into evidence-based treatments. Examination of the literature suggests various indicators of disgust that predict treatment outcome in these disorders. However, mechanisms remain unclear because studies examining disgust during the course of treatment are limited. Increasingly, the field has moved toward experimental investigation of strategies that reduce disgust. While cognitive reappraisal and imagery techniques appear promising, such techniques have yet to be examined as anxiety disorder treatments in large-scale randomized clinical trials. The literature also points to novel approaches to treating disgust, ranging from an inhibitory-informed approach to exposure therapy to transcranial direct current stimulation. However, the development of novel treatment approaches will require more rigorous experimental psychopathology approaches that can further elucidate processes that contribute to the etiology and/or maintenance of disorders of disgust.

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.

Does an unconditioned stimulus memory devaluation procedure decrease disgust memories and conditioned disgust? Results of two laboratory studies

Research has demonstrated that disgust can be installed through classical conditioning by pairing neutral conditioned stimuli (CSs) with disgusting unconditioned stimuli (USs). Disgust has been argued to play an important role in maintaining fear-related disorders. This maintaining role may be explained by conditioned disgust being less sensitive to extinction (i.e., experiencing the CS in the absence of the US). Promising alternatives to extinction training are procedures that focus on the devaluation of US memory representations. In the current study, we investigated whether such devaluation procedures can be successful to counter conditioned disgust. We conducted two laboratory studies (N = 120 and N = 51) in which disgust was conditioned using audio-visual USs. Memory representations of the USs were devalued by having participants recall these USs while they performed a taxing eye-movement task or executed one of several control tasks. The results showed successful conditioned disgust acquisition. However, no strong evidence was obtained that an US memory devaluation procedure modulates disgust memory and diminishes conditioned disgust as indicated by subjective, behavioral, or psychophysiological measures. We discuss the relevance of our results for methodological improvements regarding US memory devaluation procedures and disgust conditioning.

On the Origin of Shame: Does Shame Emerge From an Evolved Disease-Avoidance Architecture?

Shame and disgust are believed to be evolved psychological solutions to different adaptive challenges. Shame is thought to promote the maintenance of social hierarchies (Gilbert, 1997; Fessler, 2004), whereas disgust is believed to encourage disease avoidance (Curtis et al., 2004; Oaten et al., 2009). Although shame and disgust are often treated as orthogonal emotions, they share some important similarities. Both involve bodily concerns, are described as moral emotions, and encourage avoidance of social interaction. The purpose of the current research was to examine whether shame is uniquely related to disgust and pathogen avoidance. To rule out an association due to the negative valence of both emotions, guilt was also examined. In Study 1, disgust sensitivity and fear of contamination were positively correlated with shame, but not guilt, even after controlling for negative affect. In Study 2, a disgust induction increased shame, but not guilt, for individuals who were sensitive to disgust. The current research provides preliminary evidence for unique relation between shame and disgust.

Divergent strategies in faeces avoidance between two cercopithecoid primates

Parasites constitute a major selective pressure which has shaped animal behaviour through evolutionary time. One adaption to parasites consists of recognizing and avoiding substrates or cues that indicate their presence. Among substrates harbouring infectious agents, faeces are known to elicit avoidance behaviour in numerous animal species. However, the function and mechanisms of faeces avoidance in non-human primates has been largely overlooked by scientists. In this study, we used an experimental approach to investigate whether aversion to faeces in a foraging context is mediated by visual and olfactory cues in two cercopithecoid primates: mandrills (Mandrillus sphinx) and long-tailed macaques (Macaca fascicularis). Visual and olfactory cues of faeces elicited lower food consumption rates in mandrills and higher food manipulation rates in long-tailed macaques. Both results support the infection-avoidance hypothesis and confirm similar tendencies observed in other primate species. More studies are now needed to investigate the divergence of avoidance strategies observed in non-human primates regarding food contamination.

Evidence for Persistence of Sexual Evaluative Learning Effects

INTRODUCTION

Several studies demonstrated that genital arousal and enhanced positive affect toward neutral stimuli due to sexual conditioning did not extinguish during a brief extinction phase, but other studies showed contrasting results. Possible resistance to extinction of conditioned human sexual response has, however, not been studied using extensive extinction trials.

AIM

To study resistance to extinction of conditioned sexual response in men and women.

METHODS

Healthy sexually functional men (N = 34) and women (N = 32) participated in a differential conditioning experiment, with neutral pictures as conditioned stimuli (CSs) and genital vibrostimulation as unconditioned stimulus. Only one CS (the CS+) was followed by the unconditioned stimulus during the acquisition phase.

MAIN OUTCOME MEASURE

Penile circumference and vaginal pulse amplitude were assessed, and ratings of affective value and subjective sexual arousal were obtained. In addition, a stimulus response compatibility task was included to assess automatic approach and avoidance tendencies.

RESULTS

Men and women rated the CS+ as more positive than the CS- during all 24 extinction trials and demonstrated a slight tendency to approach the CS+ directly after the extinction procedure. Participants rated the CS+ as more sexually arousing than the CS- during 20 extinction trials. No evidence was found for conditioned genital sexual response.

CLINICAL IMPLICATIONS

Learned sexual evaluations may be difficult to modify through an extinction procedure; therefore, unwanted but persistent subjective sexual evaluations may be better targeted by interventions such as the deployment of emotion regulation strategies.

STRENGTH & LIMITATIONS

Extensive extinction trials were used; however, only relatively short-term effects within one experimental session were studied and there was no (unpaired) control condition.

CONCLUSION

The results provide evidence that conditioned sexual likes are relatively persistent, also at the behavioral level. Both S, Brom M, Laan E, et al. Evidence for Persistence of Sexual Evaluative Learning Effects. J Sex Med 2020;17:505-517.

Enhancing Inhibitory Learning: The Utility of Variability in Exposure

Exposure therapy has strong empirical support as a treatment for anxiety and related disorders, yet not all participants see clinically meaningful reduction in symptoms, and some experience return of fear. In this review, we examine the theoretical models of exposure therapy, from early precursors to the contemporary inhibitory learning model. The inhibitory learning model is applied to examine one potential method of improving outcomes in exposure therapy: increasing variability in the progression of the exposure hierarchy. We explore mechanisms that support the use of variability in exposure, including the violation of expectancies to enhance learning. In addition, the role of intolerance of uncertainty in anxiety is examined; variable exposure therapy could target this transdiagnostic mechanism in anxiety and related disorders. Suggestions for future research are then offered.

Effects of exposure to erotica on disgust: A preliminary test among contamination-fearful individuals

Disgust has been implicated in the fear of contamination that is commonly observed in obsessive-compulsive disorder (OCD). However, basic and treatment-oriented research has shown that disgust is resistant to extinction among those with a fear of contamination. Consequently, there is growing interest in discovering novel approaches to targeting heightened disgust responding among those with OCD. Recent experimental research suggests that sexual arousal may inhibit disgust responding. Accordingly, the present study examines the effects of exposure to erotica on verbal reports of disgust and behavioral avoidance in a contamination-fearful sample of adults. Participants viewed sexually arousing, positively arousing, or neutral films and participated in a series of sexually relevant and non-sexually relevant behavioral approach tasks. Participants also gave ratings of disgust before and after completing each behavioral task. Although no group differences were observed for the number of steps completed on the behavioral approach tasks, those who viewed sexually arousing films reported significantly less change in disgust throughout the behavioral approach task compared to those who viewed positively arousing and neutral films. The potential clinical implications of the effects of sexual arousal on disgust responding in contamination-based OCD are discussed.

Effect of Partners' Disgust Responses on Psychological Wellbeing in Cancer Patients

The aim of this study was to explore quantitatively the relationship between disgust responses in cancer patients and their partners, and in turn their relationship to patients' psychological well-being. We recruited 50 participants with heterogeneous cancer diagnoses and their partners from cancer-related groups (e.g., charities). Patients completed questionnaires to determine levels of disgust propensity, disgust sensitivity, self-disgust, and symptoms of anxiety and depression. Disgust propensity and sensitivity were also assessed in their partners. Partners' disgust sensitivity was significantly positively correlated with cancer patients' self-disgust, disgust propensity, and depression. Path analyses suggested that patients' self-disgust plays a role in mediating the effect of partners' disgust sensitivity on patients' psychological well-being. This study provides the first quantitative evidence that psychological well-being in cancer patients is contingent on their partners' sensitivity to disgust, and that patients' self-disgust plays a mediating role. Focusing therapeutically on disgust responses could well be beneficial to people with cancer.

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.

Effects of exposure in single and multiple contexts on fear renewal: The moderating role of threat-specific and nonspecific emotionality

BACKGROUND AND OBJECTIVES

The current study examines effects of exposure in multiple contexts on fear reduction and renewal and the moderating effect of baseline threat-specific and nonspecific emotionality.

METHODS

Snake-fearful participants received a negative or neutral emotion induction and were randomized to video exposure to a snake in a single context, multiple context, or a no exposure control group.

RESULTS

Anxiety in response to video presentations of a snake was significantly reduced in the two exposure groups compared to the control group, especially among those with heightened baseline threat-specific emotionality as indicated by snake anxiety ratings at baseline. Although the two exposure groups did not differ in responding when confronted with a novel snake, both exposure groups reported significantly lower snake anxiety and arousal than the control group. Subsequent analysis did show that compared to controls, the single context group demonstrated greater increase in anxiety and arousal from post-exposure to exposure to the novel snake among those with heightened snake anxiety at baseline. Furthermore, the multiple context group was less avoidant and less fearful than the single context group on a post-exposure behavioral test.

LIMITATIONS

The study used an analogue exposure paradigm with an analogue sample and findings may not be generalizable to a clinical population.

CONCLUSIONS

These findings suggest that baseline threat-specific emotionality influences fear reduction and renewal. The benefits of exposure in multiple contexts are discussed in relation to a distinct pattern of symptom change that is in line with an inhibitory learning approach.

Examining heterogeneity of obsessive-compulsive disorder: Evidence for subgroups based on motivations

Obsessive-compulsive disorder (OCD) is a heterogeneous illness and evidence suggests that different clinical characteristics may relate to varying treatment outcomes. This study was designed to identify subgroups based on core motivational domains in a clinical sample of individuals with OCD, and to compare groups on clinical characteristics. Cluster analyses identified four subgroups including groups with relatively high or low levels of both harm avoidance (HA) and incompleteness (INC) motivations. A subgroup was identified that demonstrated a "traditional profile" marked by high motivation to avoid harm, and elevated levels of beliefs about responsibility/overestimation of threat. The model also contained a subgroup characterized by high incompleteness, low motivation to avoid harm, and higher levels of perfectionistic beliefs and intolerance of uncertainty. Findings reemphasize that current cognitive and behavioral models of OCD may be enhanced by integrating incompleteness/NJREs.

Shaking that icky feeling: effects of extinction and counterconditioning on disgust-related evaluative learning

Learned disgust appears to play an important role in certain anxiety disorders, and can be explained by the process of evaluative conditioning, in which an affective evaluative reaction evoked by an unconditional stimulus (US) is transferred to a conditional stimulus (CS). Much remains unknown about how disgust-related evaluative learning can be effectively eliminated. Study 1 of the present investigation examined the effects of extinction on reducing the negative evaluation of a CS that was acquired during disgust conditioning. Participants completed acquisition trials, with a disgusting picture as US and two neutral pictures as CS (CS+ was paired with the US; CS- was unpaired), followed by extinction trials ("CS only"; experimental condition) or a filler task (control condition). Extinction trials reduced acquired US expectancy to the CS+, but did not extinguish negative evaluations of the CS+. Study 2 examined the effects of counterconditioning on evaluative learned disgust. After disgust acquisition trials, counterconditioning trials followed in which the CS+ was paired with a pleasant US (experimental condition) or a filler task (control condition). Counterconditioning trials reduced acquired US expectancy to the CS+ and reduced evaluative conditioned disgust. Implications of the potential differential effects of extinction and counterconditioning on evaluative learning for exposure-based treatment of specific anxiety disorders are discussed.

Learning to like disgust: neuronal correlates of counterconditioning

Converging lines of research suggest that exaggerated disgust responses play a crucial role in the development and maintenance of certain anxiety disorders. One strategy that might effectively alter disgust responses is counterconditioning. In this study, we used functional magnetic resonance imaging (fMRI) to examine if the neuronal bases of disgust responses are altered through a counterconditioning procedure. One disgust picture (conditioned stimulus: CS+_disg) announced a monetary reward, while a second disgust picture (CS-_disg) was never paired with the reward. Two neutral control pictures (CS+_con/CS-_con) were conditioned in the same manner. Analyses of evaluative conditioning showed that both CS+ were rated significantly more positive after conditioning as compared to the corresponding CS−. Thereby, the CS+_disg and the CS+_con received an equal increase in valence ratings. Regarding the fMRI data, ANOVA results showed main effects of the conditioning procedure (i.e., CS+ vs. CS−) in the dorsal anterior cingulate cortex. Further, main effects of the picture category (disgust vs. control) were found in the bilateral insula and the orbitofrontal cortex. No interaction effects were detected. In conclusion, the results imply that learning and anticipation of reward was not significantly influenced by the disgust content of the CS pictures. This suggests that the affect induced by the disgust pictures and the affect created by the anticipation of reward may not influence the processing of each other.