Elevated Neurobehavioral Responses to Negative Social Interactions in Women With Bulimia Nervosa.

BACKGROUND: Bulimia nervosa (BN) is a complex psychiatric illness that includes binge-purge behaviors and a belief that one's value as a person depends on body shape and weight. Social pressure strongly influences the development and maintenance of BN, but how this manifests neurobiologically within an individual remains unknown. We used a computational psychiatry approach to evaluate neural mechanisms underlying social interactions in BN. METHODS: Behavioral and functional magnetic resonance imaging data were collected from 24 women with BN and 26 healthy comparison women using an iterated social exchange game. Data were sorted round by round based on whether the mathematically computed social signals indicated an improving (positive reciprocity) or deteriorating (negative reciprocity) relationship for each participant. RESULTS: Social interactions with negative reciprocity resulted in more negative behavioral responses and stronger neural activations in both cortical and subcortical regions in women with BN than healthy comparison women. No behavioral or neural differences were observed for interactions demonstrating positive reciprocity, suggesting a very specific form of psychopathology in BN: amplification of negative self-relevant social interactions. Cortical activations (e.g., temporoparietal junction and dorsolateral prefrontal cortex) did not covary with mood symptoms, while subcortical activations (e.g., amygdala and dorsal striatum) were associated with acute psychopathology. CONCLUSIONS: These data provide a first step toward a mechanistic neuropsychological model of aberrant social processing in BN, demonstrating how a computational psychiatric approach can elucidate neural mechanisms for complex psychiatric illnesses. Future treatments for BN may include targeting neural regions that support these negative biases in social perceptions.

Neural processes related to negative self-concept in adult and adolescent anorexia nervosa.

OBJECTIVE: Negative self-concept is characteristic of anorexia nervosa (AN), but the neural processes mediating this component of AN is unknown. These studies investigated how valence and social perspectives impact neural processing in both adults and adolescents with AN. METHOD: In an fMRI task, participants evaluated positive and negative adjectives from three social perspectives. Two studies were completed, one in 59 women (healthy, with AN, recovered from AN) and one in 42 adolescents (healthy, with AN). Neural regions of interest (ROIs) related to valence were identified and activations compared across groups and social perspectives. RESULTS: Behaviourally, both adult and adolescent cohorts with AN were less positive during self-evaluations. In the adult study, neural differences related to clinical group and condition were observed in ROIs more responsive to positive social stimuli (medial prefrontal cortex, precuneus, left temporoparietal junction) but not in ROIs more responsive to negative social stimuli. No neural differences in relation to clinical group were observed in the adolescents. CONCLUSIONS: Behavioural differences related to negative self-concept are present in both adolescents and adults with AN, and neural differences, selective for positive social stimuli, were also observed in adults. AN may interfere with neurodevelopmental processes involved in positive self-concept.

Violence From a Sexual Partner is Significantly Associated With Poor HIV Care and Treatment Outcomes Among Female Sex Workers in the Dominican Republic.

BACKGROUND: Female sex workers (FSWs) experience high rates of violence from their sexual partners. Although violence is associated with HIV risk behaviors among FSWs, there is limited evidence on the association between violence and HIV treatment outcomes. METHODS: We analyzed data from a socio-behavioral survey with a cohort of FSWs living with HIV in the Dominican Republic (n = 268) to describe the burden of violence from a sexual partner in the last 6 months. We assessed the relationship between violence and HIV treatment outcomes, comparing findings across 2 types of sexual partners: intimate partners and clients. RESULTS: Nearly one-fifth of women (18.3%) experienced violence in the last 6 months. More women experienced violence from an intimate partner (12.3%) than a client (8.3%), with some (2.6%) reporting both. Although violence from an intimate partner was significantly associated with not currently being on antiretroviral treatment [ART; adjusted odds ratio (AOR): 4.05, 95% confidence interval (CI): 1.00 to 16.36] and missing an ART dose in the last 4 days (AOR: 5.26, 95% CI: 1.91 to 14.53), violence from a client was associated with never having received HIV care (AOR: 2.85, 95% CI: 1.03 to 7.92) and ever interrupting ART (AOR: 5.45, 95% CI: 1.50 to 19.75). CONCLUSIONS: Violence from a sexual partner is associated with poor HIV treatment outcomes among FSWs. Different patterns by type of partner reflect how relationship dynamics may influence these associations. Violence prevention and support services should be tailored based on type of partner. Violence screening and referrals should be integrated into HIV care services for FSWs to improve their health and reduce ongoing transmission.