Emily L. Belleau

How related are hair pulling disorder (trichotillomania) and skin picking disorder? A review of evidence for comorbidity, similarities and shared etiology

Hair pulling disorder (HPD; trichotillomania) and skin picking disorder (SPD) are relatively common and potentially severe psychiatric conditions that have received limited empirical attention. Researchers are increasingly recognizing the similarities and co-occurrence of HPD and SPD, and several authors have suggested that the two disorders should be categorized together in the DSM-5. In the present article, we critically examined the evidence for comorbidity of HPD and SPD, and reviewed a diverse literature pertaining to shared risk factors and similarities in clinical characteristics. Evidence suggests that the two disorders co-occur more often than can be expected by chance, have substantial similarities in a variety of clinical characteristics (e.g., symptom presentation and course of illness) and may have some distal risk factors in common (e.g., genetic vulnerabilities). Implications for classification in the DSM-5, clinical management and research on etiology were discussed.

Imbalance of default mode and regulatory networks during externally focused processing in depression

Attentional control difficulties likely underlie rumination, a core cognitive vulnerability in major depressive disorder (MDD). Abnormalities in the default mode, executive and salience networks are implicated in both rumination and attentional control difficulties in MDD. In the current study, individuals with MDD (n = 16) and healthy controls (n = 16) completed tasks designed to elicit self-focused (ruminative) and externally-focused thinking during fMRI scanning. The MDD group showed greater default mode network connectivity and less executive and salience network connectivity during the external-focus condition. Contrary to our predictions, there were no differences in connectivity between the groups during the self-focus condition. Thus, it appears that when directed to engage in self-referential thinking, both depressed and non-depressed individuals similarly recruit networks supporting this process. In contrast, when instructed to engage in non-self-focused thought, non-depressed individuals show a pattern of network connectivity indicative of minimized self-referential processing, whereas depressed individuals fail to reallocate neural resources in a manner consistent with effective down regulation of self-focused thought. This is consistent with difficulties in regulating self-focused thinking in order to engage in more goal-directed behavior that is seen in individuals with MDD.

Aberrant executive attention in unaffected youth at familial risk for mood disorders

BACKGROUND Aberrant attentional processes in individuals with mood disorders - bipolar disorder (BD) and major depressive disorder (MDD) - have been well documented. This study examined whether unaffected youth at familial risk for mood disorders would exhibit poor alerting, orienting, and executive attention relative to age-matched controls. METHODS A sample of youth (8-17 years old) having one parent with either BD or MDD (Mood-Risk, n=29) and youth having healthy parents (HC, n=27) completed the Attention Network Test-Short version (ANT-S), which assesses alerting, orienting, and executive attention. RESULTS Relative to HCs, the Mood-Risk group had significantly slower reaction times on an index of executive attention, but no differences on indices of alerting or orienting. There were no differences between the two at-risk groups (i.e., youth with BD parent vs. youth with MDD parent) on any ANT-S measure. LIMITATIONS The current study is limited by its cross-sectional design, small sample size, and failure to control for familial environmental factors. CONCLUSIONS The findings extend previous results indicating that altered executive attention may represent an endophenotype for mood disorders in at-risk youth.

Negatively Biased Emotion Perception in Depression as a Contributing Factor to Psychological Aggression Perpetration: A Preliminary Study

ABSTRACT Based on research linking depressive symptoms and intimate partner aggression perpetration with negatively biased perception of social stimuli, the present authors examined biased perception of emotional expressions as a mechanism in the frequently observed relationship between depression and psychological aggression perpetration. In all, 30 university students made valence ratings (negative to positive) of emotional facial expressions and completed measures of depressive symptoms and psychological aggression perpetration. As expected, depressive symptoms were positively associated with psychological aggression perpetration in an individuals current relationship, and this relationship was mediated by ratings of negative emotional expressions. These findings suggest that negatively biased perception of emotional expressions within the context of elevated depressive symptoms may represent an early stage of information processing that leads to aggressive relationship behaviors.

The effects of stimulus novelty and negativity on BOLD activity in the amygdala, hippocampus, and bed nucleus of the stria terminalis

Abstract The amygdala responds to stimulus novelty, which may correspond to an evaluation of novel stimuli for potential threat, and trait anxiety may modulate this response. The bed nucleus of the stria terminalis (BNST) may also be sensitive to novelty as it responds to both uncertainty and threat. If so, a BNST novelty response may also be affected by trait anxiety and interact with stimulus negativity. We presented participants with novel and repeated negative and neutral images while measuring brain activity via fMRI, and assessed participants’ self-reported trait anxiety. We expected to replicate past findings of novelty responses in the hippocampus and amygdala that are independent of stimulus negativity. We also expected BNST novelty-sensitivity and that trait anxiety would predict greater sensitivity to both novelty and negativity in the amygdala and BNST, but not the hippocampus. Our a priori analyses replicated past findings of a novelty response that was independent of valence in the hippocampus and amygdala. The BNST exhibited a novelty response for negative, but not neutral, images. Trait anxiety did not modulate the response to novelty or negativity in any of the ROIs investigated. Our findings suggest that the BNST plays a role in the detection of novelty. Key words: novelty; bed nucleus of the stria terminalis; BNST; amygdale; fMRI; BST

Cortical Gyrification Patterns Associated with Trait Anxiety

Dispositional anxiety is a stable personality trait that is a key risk factor for internalizing disorders, and understanding the neural correlates of trait anxiety may help us better understand the development of these disorders. Abnormal cortical folding is thought to reflect differences in cortical connectivity occurring during brain development. Therefore, assessing gyrification may advance understanding of cortical development and organization associated with trait anxiety. Previous literature has revealed structural abnormalities in trait anxiety and related disorders, but no study to our knowledge has examined gyrification in trait anxiety. We utilized a relatively novel measure, the local gyrification index (LGI), to explore differences in gyrification as a function of trait anxiety. We obtained structural MRI scans using a 3T magnetic resonance scanner on 113 young adults. Results indicated a negative correlation between trait anxiety and LGI in the left superior parietal cortex, specifically the precuneus, reflecting less cortical complexity among those high on trait anxiety. Our findings suggest that aberrations in cortical gyrification in a key region of the default mode network is a correlate of trait anxiety and may reflect disrupted local parietal connectivity.

Using the Research Domain Criteria Framework to Track Domains of Change in Comorbid PTSD and SUD.

Objectives: Comorbidity in diagnosis raises critical challenges for psychological assessment and treatment. The Research Domain Criteria (RDoC) Project, launched by the National Institutes of Mental Health, proposes domains of functioning as a way to conceptualize the overlap between comorbid conditions and inform treatment selection. However, further research is needed to understand common comorbidities (e.g., posttraumatic stress disorder [PTSD] and substance use disorder [SUD]) from an RDoC framework and how existing evidence-based treatments would be expected to promote change in the RDoC domains of functioning. To address these gaps, the current study examined change in 3 RDoC domains (Negative Valence Systems, Arousal/Regulatory Systems, and Cognitive Systems) during concurrent prolonged exposure (PE) and substance use treatment. Method: Participants were 85 individuals with co-occurring PTSD and SUD who received PE in a residential substance use treatment facility. They completed an experimental task to assess physiological reactivity to trauma and alcohol cues at pre- and posttreatment. Results: Results showed decreased severity in all 3 RDoC domains of interest across the study period. Pairwise comparisons between domains revealed that Arousal/Regulatory Systems had the lowest severity at posttreatment. Subsequent hierarchical linear regression analyses showed that posttreatment domain scores were associated with posttreatment cue reactivity for trauma and alcohol cues. Conclusions: The findings provide preliminary evidence of how the RDoC domains of functioning may change with evidence-based treatments and are discussed in terms of the assessment and treatment of mental health problems using the RDoC framework.

Pre-treatment predictors of dropout from prolonged exposure therapy in patients with chronic posttraumatic stress disorder and comorbid substance use disorders

Posttraumatic stress disorder (PTSD) and substance use disorders (SUDs) are commonly co-occurring disorders associated with more adverse consequences than PTSD alone. Prolonged exposure therapy (PE) is one of the most efficacious treatments for PTSD. However, among individuals with PTSD-SUD, 35-62% of individuals drop out of trauma-focused exposure treatments. Thus, it is important to identify predictors of PTSD treatment dropout among substance abusers with PTSD in order to gain information about adapting treatment strategies to enhance retention and outcomes. The current study explored pre-treatment predictors of early termination from PE treatment in a sample of 85 individuals receiving concurrent treatment for PTSD and a SUD in a residential treatment facility as part of a randomized controlled trial. The results indicated that less education and more anxiety sensitivity uniquely predicted PE treatment dropout. Demographic variables, PTSD severity, SUD severity, mental health comorbidities, and emotion regulation difficulties did not predict treatment dropout. These results suggest that adding pre-treatment interventions that address anxiety sensitivity, and promote social adjustment and cognitive flexibility, could possibly improve PE retention rates in clients with high anxiety or low education.

Cortico-limbic connectivity changes following fear extinction and relationships with trait anxiety

Abstract Fear extinction is a powerful model of adaptive and anxiety‐related maladaptive fear inhibition. This learning process is dependent upon plastic interactions between the amygdala, the anterior midcingulate cortex (aMCC), the hippocampus, and the ventromedial prefrontal cortex (vmPFC). With regard to the amygdala, the basolateral (BLA) and centromedial amygdala (CMA) serve unique roles in fear extinction. In a large sample (N = 91), the current study examined pre‐ to post‐extinction changes in resting state functional connectivity (RSFC) of fear inhibition and expression pathways. We also examined how trait anxiety and extinction performance were associated with extinction‐related changes within these neural pathways. We found stronger pre‐ to post‐extinction RSFC in pathways known to play a role in the down‐regulation of fear responses (BLA‐hippocampus, aMCC‐hippocampus, CMA‐hippocampus, CMA‐aMCC). We also found that trait anxiety was associated with strengthening of a BLA‐aMCC circuit supporting fear expression following extinction learning. Furthermore, we found that physiological indices of poorer extinction learning were linked to weaker pre‐ to post‐extinction RSFC of a BLA‐hippocampus pathway important for fear extinction consolidation. Our results highlight the network changes that occur during extinction, the separable role of CMA and BLA‐based circuitry and a key pathway linked to risk for anxiety pathology.

Depression is associated with dimensional and categorical effects on white matter pathways

Diffusion tensor imaging (DTI) studies report reduced fractional anisotropy (FA) in major depressive disorder (MDD). However, whether FA covaries with key depressive symptoms, such as anhedonia, is unclear.