A network analysis of mechanisms of change during exposures over the course of intensive OCD treatment.

Exposure and response prevention (ERP) is an evidence-based treatment for obsessive-compulsive disorder (OCD). Theories for how it works vary in their emphasis on active mechanisms of change. The current study aimed to clarify mechanisms of change in ERP for OCD using network analysis, comparing ERP networks at the start and end of intensive treatment (partial hospital and residential). In our sample of 182 patients, the most central node in both networks was engagement with exposure, which was consistently related to greater understanding of ERP rationale, higher willingness, and less ritualization, accounting for all other variables in the network. There were no significant differences in networks between the start and end of treatment. These results suggest that nonspecific parameters like facilitating engagement in exposures without ritualizing and providing a clear rationale to clients may be key to effective treatment. As such, it may be useful for clinicians to spend adequate time underscoring the need to eliminate rituals to fully engage in exposure tasks and explaining the rationale for ERP prior to doing exposures, regardless of theoretical orientation. Nonetheless, findings represent group-level statistics and more fine-grained idiographic analyses may reveal individual-level differences with respect to central mechanisms of change. Other limitations include demographic homogeneity of our sample.

Urged to feel certain again: The role of emotion-related impulsivity on the relationships between intolerance of uncertainty and OCD symptom severity.

OBJECTIVES: Obsessive-compulsive disorder (OCD) is a debilitating mental disorder characterized by persistent and intrusive thoughts accompanied by repetitive mental or physical acts. While both intolerance of uncertainty and emotion-related impulsivity have been consistently evidenced as cognitive risk factors of OCD, no studies have considered their joint effects. The current study examined the interaction between intolerance of uncertainty and two forms of emotion-related impulsivity-including both a behavioural and cognitive form-in predicting OCD symptoms. DESIGN: Cross-sectional data were collected online from community-based adult participants. METHODS: Participants (N = 673) completed a battery of self-report measures of OCD symptom severity, intolerance of uncertainty, and emotion-related impulsivity. RESULTS: The behavioural form of emotion-related impulsivity positively moderated the relationship between intolerance of uncertainty and OCD symptoms. Elevated levels of both factors predicted the most severe symptoms, particularly checking, washing, and obsessing. This interaction effect was not found for the cognitive form of emotion-related impulsivity, which still emerged as a unique predictor of OCD symptom severity, specifically obsessing symptoms. CONCLUSIONS: Current findings furthered the understanding of the link between intolerance of uncertainty and OCD symptoms by highlighting the role of emotion-related impulsivity. When uncertainty triggers distress in individuals with high intolerance of uncertainty, the urge to behaviourally alleviate this distress could promote the use of maladaptive obsessions and compulsions, leading to greater OCD symptoms. Results also indicated the potentially differential effects from the behavioural versus cognitive forms of emotion-related impulsivity on different symptom domains, and the mechanistic link here is worthy of further investigation.

Feeling more confident to encounter negative emotions: The mediating role of distress tolerance on the relationship between self-efficacy and outcomes of exposure and response prevention for OCD.

BACKGROUND: While exposure and response prevention (ERP) is the first-line treatment for obsessive-compulsive disorder (OCD), up to half of patients do not effectively respond. In an effort to better understand the mechanisms behind ERP, the inhibitory learning model emphasizes the roles of increasing perceived self-efficacy and distress tolerance. While self-efficacy and distress tolerance have separately been shown to predict OCD symptoms and treatment outcomes, no studies have assessed their joint effects in ERP. The current study examined distress tolerance as a mediator of the relationship between self-efficacy and ERP outcomes. METHODS: Patients in an intensive ERP-based treatment program (N = 116) completed weekly self-report measures. RESULTS: Over the course of treatment, as OCD symptoms reduced, self-efficacy and distress tolerance both significantly increased. Importantly, increases in self-efficacy and distress tolerance mediated each other in explaining symptom reduction, suggesting a possible bi-directional effect. LIMITATIONS: The temporal relationship between changes in self-efficacy and distress tolerance is worthy of further investigation. In addition, the current sample had limited racial diversity and might not be representative of patients receiving lower levels of care. Findings merit replication to be ascertained of their reliability. CONCLUSIONS: Findings suggest that during ERP, patients gain confidence in their abilities both to cope with general challenges and to withstand distress, potentially helping them engage with exposures and overcome initial fears. These findings provide support for the inhibitory learning model and highlight the mechanistic roles of self-efficacy and distress tolerance in ERP. Clinical implications to target both in treatment are discussed.

S1/S0 Potential Energy Surfaces Experience Different Types of Restricted Rotation: Restricted Z/ E Photoisomerization and E/ Z Thermoisomerization by an Out-of-Plane Benzyl Group or In-Plane m-Pyridinium Group?

Any method that can enhance the fluorescence of fluorophores is highly desirable. Fluorescence enhancement accomplished by restricted Z/ E photoisomerization through intramolecular steric hindrance or relatively high bond order of a C═C double bond in a S1 excited state has rarely been studied. In this article, we used green fluorescent protein (GFP) chromophore analogues as a model to get new physical insights into the restricted Z/ E photoisomerization and E/ Z thermoisomerization phenomena. We found that the S1 and S0 potential energy surfaces (PESs) of the GFP chromophore analogues experience two dramatically different types of restricted rotation, and 2b can be a representative example. In its S1 PES, it is not the intramolecular steric hindrance between the out-of-plane benzyl group and the in-plane m-pyridinium group but the relatively high bond order of the I-bond in the S1 excited state of 2b that makes it have a higher barrier for the Z/ E photoisomerization, a smaller Z/ E photoisomerization quantum yield, and a higher fluorescence quantum yield. In its S0 PES, it is not the reduced bond order of the I-bond in the S0 ground state of 2b but the intramolecular steric hindrance between the out-of-plane benzyl group and the in-plane m-pyridinium group that makes it have an extra higher barrier for E/ Z thermoisomerization and a much smaller E/ Z thermoisomerization rate constant.