Neural correlates of body image processing in binge eating disorder.

Although body image disturbances play a central role in the development, maintenance and relapse of binge eating disorder (BED), studies investigating the neural basis underlying body processing in BED are still missing. To address this gap, we conducted a preregistered (German Clinical Trials Register [Deutsches Register Klinischer Studien; DRKS], Registration DRKS00008107) combined functional magnetic resonance (fMRI)/eye tracking study in which 38 women with BED and 22 healthy controls weight-matched for overall equivalence processed images of their own bodies, an unfamiliar weight-matched body, and visually matched nonbody control stimuli while performing a one-back task. Women with BED responded with higher left fusiform body area (FBA) activity than controls during body image processing. Despite higher levels of self-reported body dissatisfaction, women with BED did not show overactivation in emotion-processing areas in response to their own body. The eye-tracking results indicated that visual attention toward the presented stimuli was associated with increased activity in the extrastriate body area (EBA) and FBA across groups. Our results thus provide evidence for an aberrant neural processing of body images in BED and highlight the importance of controlling for visual attention in future studies assessing neuronal body processing. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Stress effects on the oddball P300 and N2 in males and females.

We examined the effect of psychosocial stress on electrophysiological markers of novelty and deviance processing, the N2 and P300, as well as sex differences therein. Participants underwent the Trier Social Stress Test (TSST) or a control procedure, followed by an oddball paradigm. A physiological stress response was induced in both sexes in the TSST condition. Furthermore, a reduced target P300 amplitude was elicited in the TSST condition in fronto-central electrodes, an effect that did not differ in magnitude between both sexes. By contrast, stressor effects on N2 amplitude differed by sex: In females, N2 amplitude was decreased in the TSST condition, while in males, no stress effects were observed. Exploratory correlational analyses suggested that a stress-induced P300 amplitude reduction, at least in males, could be due to a modulation of adrenergic activity. These results are consistent with sex differences in the manner in which stress affects lower-level, stimulus-driven vs. higher-level, more controlled processing stages.

Gaze behavior is associated with the cortisol response to acute psychosocial stress in the virtual TSST.

BACKGROUND: The Trier Social Stress Test (TSST) is a reliable tool for psychobiological stress induction. Because of its socio-evaluative nature, it has been useful for investigating gaze behavior. It has been shown that healthy people avoid looking toward faces when under stress, a finding that corroborates studies demonstrating avoidance of eye contact in social anxiety disorder. Yet, little is known about the relationship between gaze behavior and the biological stress response. METHODS: In a final sample of 74 healthy males, a virtual reality version of the Trier Social Stress Test (TSST-VR) with an integrated eye tracker was implemented to investigate gaze behavior during acute stress induction. Stress response measures were collected via saliva samples and subjective stress ratings. Additional questionnaires were administered for examining the influence of social anxiety traits. RESULTS: The TSST-VR elicited a significant psychobiological stress response. Overall, higher gaze times on judges compared to surroundings were found in the speech task while this pattern was reversed in the arithmetic task. Critically, there was a significant negative association between gaze time on judges and cortisol output in cortisol responders. CONCLUSIONS: In a non-clinical sample, avoidance of gaze is associated with a stronger cortisol response to acute stress. This study demonstrates the potential of eye tracking to disentangle the effects of acute stress on social interaction, warranting further investigation in clinical populations characterized by high levels of anxiety in social situations, such as social anxiety and autism spectrum disorder.

Looking at the bigger picture: Cortical volume, thickness and surface area characteristics in borderline personality disorder with and without posttraumatic stress disorder.

Borderline personality disorder (BPD) is a severe psychiatric disorder accompanied by multiple comorbidities. Neuroimaging studies have identified structural abnormalities in BPD with most findings pointing to gray matter volume reductions in the fronto-limbic network, although results remain inconsistent. Similar alterations were found in posttraumatic stress disorder (PTSD), a common comorbidity of BPD. Only a small number of studies have investigated structural differences in BPD patients regarding comorbid PTSD specifically and studies conducting additional surface analyses are scarce. We investigated structural differences in women with BPD with and without PTSD and non-patient controls. Automated voxel-based and region-based volumetric analyses were applied. Additionally, four surface-based measures were analyzed: cortical thickness, gyrification index, fractal dimension, and sulcus depth. Analyses did not identify cortical volume alterations in the fronto-limbic network. Instead, hypergyrification was detected in the right superior parietal cortex in BPD patients compared to non-patient controls. No distinction was revealed between BPD patients with and without PTSD. These findings underline the importance of a holistic investigation examining volumetric and surface measures as these might enhance the understanding of structural alterations in BPD.