Faculty Bibliography

Hoarding disorder (HD) is a new psychiatric diagnosis in Diagnostic and Statistical Manual of Mental Disorders-Fifth edition and preliminary evidence suggests that cognitive-behavioral treatments are effective in treating this condition. However, it has been demonstrated that individuals with HD generally display poor compliance during treatment, which may lead to poor outcomes. Treatment compliance can be conceptualized as either within-session or between-session compliance, but currently there are no validated measures of within-session or between-session compliance specifically for HD. The aim of this study was to provide an initial validation of the CBT Compliance Measure and the Patient Exposure/Response Prevention Adherence Scale for Hoarding in a sample of participants with HD who were undergoing group cognitive behavioral therapy (CBT) for HD (N = 70). Both measures, which were administered at each relevant treatment session, demonstrated a unidimensional structure, good reliability, as well as predictive validity, and are thus promising in the measurement of within-session and between-session compliance with CBT for HD.

Disrupted interoceptive processes are present in a range of psychiatric conditions, and there is a small but growing body of research on the role of interoception in obsessive-compulsive disorder (OCD). In this review, we outline dimensions of interoception and review current literature on the processing of internal bodily sensations within OCD. Investigations in OCD utilizing objective measures of interoception are limited and results mixed, however, the subjective experience of internal bodily sensations appears to be atypical and relate to specific patterns of symptom dimensions. Further, neuroimaging investigations suggest that interoception is related to core features of OCD, particularly sensory phenomena and disgust. Interoception is discussed in the context of treatment by presenting an overview of existing interventions and suggesting how modifications aimed at better targeting interoceptive processes could serve to optimize outcomes. Interoception represents a promising direction for multi-method research in OCD, which we expect, will prove useful for improving current interventions and identifying new treatment targets.

BACKGROUND:Recent evidence suggests that repetitive transcranial magnetic stimulation (rTMS) might be effective in treating generalized anxiety disorder (GAD). Cognitive models of GAD highlight the role of intolerance of uncertainty (IU) in precipitating and maintaining worry, and it has been hypothesized that patients with GAD exhibit decision-making deficits under uncertain conditions. Improving understanding of the neural mechanisms underlying cognitive deficits associated with IU may lead to the identification of novel rTMS treatment targets and optimization of treatment parameters. The current report describes two interrelated studies designed to identify and verify a potential neural target for rTMS treatment of GAD. METHODS:Study I explored the integrity of prefrontal cortex (PFC) and amygdala neural networks, which underlie decision making under conditions of uncertainty, in GAD. Individuals diagnosed with GAD (n = 31) and healthy controls (n = 20) completed a functional magnetic resonance imaging (fMRI) gambling task that manipulated uncertainty using high versus low error rates. In a subsequent randomized-controlled trial (Study II), a subset of the GAD sample (n = 16) completed the fMRI gambling task again after 30 sessions of active versus sham rTMS (1 Hz, right dorsolateral prefrontal cortex) to investigate the modulation of functional networks and symptoms. RESULTS:In Study I, participants with GAD demonstrated impairments in PFC-PFC and PFC-amygdala functional connectivity (FC) mostly during the high uncertainty condition. In Study II, one region of interest pair, dorsal anterior cingulate (ACC) - subgenual ACC, showed "normalization" of FC following active, but not sham, rTMS, and neural changes were associated with improvement in worry symptoms. CONCLUSIONS:These results outline a possible treatment mechanism of rTMS in GAD, and pave the way for future studies of treatment optimization.

Generalized anxiety disorder (GAD) and social anxiety disorder (SAD) are currently considered distinct diagnostic categories. Accumulating data suggest the study of anxiety disorders may benefit from the use of dimensional conceptualizations. One such dimension of shared dysfunction is emotion regulation (ER). The current study evaluated dimensional (ER) and categorical (diagnosis) neurocorrelates of resting-state functional connectivity (rsFC) in participants with GAD and SAD and healthy controls (HC). Functional magnetic resonance imaging (fMRI) rsFC was estimated between all regions of the default mode network (DMN), salience network (SN), and bilateral amygdala (N = 37: HC-19; GAD-10; SAD-8). Thereafter, rsFC was predicted by both ER, (using the Difficulties in Emotion Regulation Scale [DERS]), and diagnosis (DSM-5) within a single unified analysis of covariance (ANCOVA). For the ER dimension, there was a significant association between impaired ER abilities and anticorrelated rsFC of amygdala and DMN (L.amygdala-ACC: p = 0.011, beta = -0.345), as well as amygdala and SN (L.amygdala-posterior cingulate cortex [PCC]: p = 0.032, beta = -0.409). Diagnostic status was significantly associated with rsFC differences between the SAD and HC groups, both within the DMN (PCC-MPFC: p = 0.009) and between the DMN and SN (R.LP-ACC: p = 0.010). Although preliminary, our results exemplify the potential contribution of the dimensional approach to the study of GAD and SAD and support a combined categorical and dimensional model of rsFC of anxiety disorders.

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.