Frontotemporal neural systems supporting semantic processing in Alzheimer’s disease

We hypothesized that semantic memory for object concepts involves both representations of visual feature knowledge in modality-specific association cortex and heteromodal regions that are important for integrating and organizing this semantic knowledge so that it can be used in a flexible, contextually appropriate manner. We examined this hypothesis in an fMRI study of mild Alzheimer’s disease (AD). Participants were presented with pairs of printed words and asked whether the words matched on a given visual–perceptual feature (e.g., guitar, violin: SHAPE). The stimuli probed natural kinds and manufactured objects, and the judgments involved shape or color. We found activation of bilateral ventral temporal cortex and left dorsolateral prefrontal cortex during semantic judgments, with AD patients showing less activation of these regions than healthy seniors. Moreover, AD patients showed less ventral temporal activation than did healthy seniors for manufactured objects, but not for natural kinds. We also used diffusion-weighted MRI of white matter to examine fractional anisotropy (FA). Patients with AD showed significantly reduced FA in the superior longitudinal fasciculus and inferior frontal-occipital fasciculus, which carry projections linking temporal and frontal regions of this semantic network. Our results are consistent with the hypothesis that semantic memory is supported in part by a large-scale neural network involving modality-specific association cortex, heteromodal association cortex, and projections between these regions. The semantic deficit in AD thus arises from gray matter disease that affects the representation of feature knowledge and processing its content, as well as white matter disease that interrupts the integrated functioning of this large-scale network.     

Top Ten Questions Male Sexual Abuse Survivors Want to Know from Health Care Research

Sexual abuse is an often overlooked public health issue for boys and men. Given its prevalence and well-documented connection to mental and physical health disorders, the relevance of male survivor input and engagement in health care research is profound. Using a community-based participatory research design, an in-person focus group with male survivors of sexual abuse and researchers was conducted. This paper describes the top ten research questions male sexual abuse survivors would like to have answered. Survivors were most interested in knowing how sexual abuse and assault impact men’s emotional and sexual functioning, what factors are involved in preventing and treating sexual assault-related emotional distress, and what can be done to prevent sexual abuse of boys and men. The fact that some of the questions survivors expressed an interest in knowing about have actually previously been investigated by researchers suggests a disconnect in translating evidence-based findings. Clinical and research implications include designing outreach interventions and gender-specific psychoeducation to increase engagement and access to care for men.     

Taking religion to heart: the relationship between the Five Factor Model and the New Indices of Religious Orientation among religious students

The relationship between religious orientation and personality has been investigated using several different measures and diverse samples. As part of a larger study, 114 undergraduate students were given the Duke University Religion Index (DUREL) to include only those participants who were considered religious. The final sample of 80 participants were given the NEO Personality Inventory-Revised (NEO PI-R) and the New Indices of Religious Orientation (NIRO). Based on the results of the bivariate correlations, higher levels of intrinsic religious orientation were associated with greater Agreeableness and Conscientiousness. Multivariate analyses further revealed that Agreeableness was the most important personality variable when predicting intrinsic and quest religious orientations, with higher levels of Agreeableness predicting greater intrinsic and lower quest orientations. While lower levels of Neuroticism predicted greater intrinsic orientation, higher levels of Neuroticism predicted greater quest orientations. Higher Conscientiousness predicted greater intrinsic and lower quest orientations. Implications of these findings are discussed.     

On the relation between theory of mind and executive functioning: A developmental cognitive neuroscience perspective

Theory of mind (ToM) and executive functioning (EF) show marked interrelatedness across childhood, and developmental psychologists have long been interested in understanding the nature of this association. The present review addresses this issue from a cognitive neuroscience perspective by exploring three hypotheses regarding their functional overlap: (1) ToM relies on EF (EF→ToM); (2) EF relies on ToM (ToM→EF); and (3) ToM and EF are mutually related, owing to shared neural structures or networks (ToM?EF). Drawing on evidence from normative brain development, neurodevelopmental and neurodegenerative diseases, patient lesion studies, and brain-imaging studies, we suggest that only a strict version of the ToM?EF proposal of complete neural overlap can be confidently ruled out on the basis of existing evidence. The balance of evidence suggests that separable neurobiological mechanisms likely underlie ToM and EF, with shared mechanisms for domain-general processing that support both abilities. We highlight how future studies may empirically substantiate the nature of the ToM–EF relationship using various biobehavioral approaches.     

Augmenting treatment efficiency in exposure therapy for PTSD: a randomized double-blind placebo-controlled trial of yohimbine HCl

The alpha-2 adrenergic receptor antagonist, yohimbine, can facilitate fear extinction in animals and humans. One potential mechanism is increased noradrenergic activity and associated arousal in the presence of conditioned stimuli. Accordingly, yohimbine might augment prolonged exposure (PE) therapy for posttraumatic stress disorder (PTSD), where heightened exposure-oriented arousal is a theorized driver and empirical predictor of treatment success. A double-blind placebo-controlled randomized trial (NCT 01031979) piloted yohimbine augmentation in 26 males with combat-related PTSD. Participants were given one-time dose of yohimbine or placebo prior to the first imaginal exposure. Subsequently, both arms completed standard PE. The primary outcome was trauma-cued heart-rate reactivity a week after the drug/exposure visit, a highly specified, objective measure sensitive to incremental change. Secondary outcomes included arousal during the drug/exposure visit and slope of distress, PTSD, and depression over the course of PE. Consistent with hypothesis, yohimbine led to higher objective and subjective arousal during the drug/exposure visit and to lower trauma-cued heart-rate reactivity one-week later. One dose of yohimbine also led to greater between-session habituation and more rapid improvement on depression, but not PTSD, over the course of care. Results of this controlled pilot indicate support for continued investigation of yohimbine-augmented exposure therapy for PTSD.     

Acceptability,Feasibility, and Effectiveness of Internet-Based Cognitive-Behavioral Therapy for Obsessive-Compulsive Disorder in New York

Cognitive-behavioral therapy (CBT), consisting of exposure and response prevention (EX/RP), is both efficacious and preferred by patients with obsessive–compulsive disorder (OCD), yet few receive this treatment in practice. This study describes the implementation of an Internet-based CBT program (ICBT) developed in Sweden in individuals seeking OCD treatment in New York. After translating and adapting the Swedish ICBT for OCD, we conducted an open trial with 40 adults with OCD. Using the RE-AIM implementation science framework, we assessed the acceptability, feasibility, and effectiveness of ICBT. The Yale–Brown Obsessive Compulsive Scale (Y-BOCS) was the primary outcome measure. Of 40 enrolled, 28 participants completed the 10-week ICBT. In the intent-to-treat sample (N = 40), Y-BOCS scores decreased significantly over time (F = 28.12, df = 2, 49, p < . 001). Depressive severity (F = 5.87, df = 2, 48, p < . 001), and quality of life (F = 12.34, df = 2, 48, p < . 001) also improved. Sensitivity analyses among treatment completers (N = 28) confirmed the intent-to-treat results, with a large effect size for Y-BOCS change (Cohen’s d = 1.38). ICBT took less time to implement than face-to face EX/RP and participants were very to mostly satisfied with ICBT. On a par with results in Sweden, the adapted ICBT program reduced OCD and depressive symptoms and improved quality of life among individuals with moderate to severe OCD. Given its acceptability and feasibility, ICBT deserves further study as a way to increase access to CBT for OCD in the United States.     

Strategies in probabilistic categorization: results from a new way of analyzing performance

The "Weather Prediction" task is a widely used task for investigating probabilistic category learning, in which various cues are probabilistically (but not perfectly) predictive of class membership. This means that a given combination of cues sometimes belongs to one class and sometimes to another. Prior studies showed that subjects can improve their performance with training, and that there is considerable individual variation in the strategies subjects use to approach this task. Here, we discuss a recently introduced analysis of probabilistic categorization, which attempts to identify the strategy followed by a participant. Monte Carlo simulations show that the analysis can, indeed, reliably identify such a strategy if it is used, and can identify switches from one strategy to another. Analysis of data from normal young adults shows that the fitted strategy can predict subsequent responses. Moreover, learning is shown to be highly nonlinear in probabilistic categorization. Analysis of performance of patients with dense memory impairments due to hippocampal damage shows that although these patients can change strategies, they are as likely to fall back to an inferior strategy as to move to more optimal ones.