The neural correlates of socio-cognitive factors and eating disorders in young people: A systematic review

A Narrative Review on the Neurocognitive Profiles in Eating Disorders and Higher Weight Individuals: Insights for Targeted Interventions

Background/Objectives: Recent research has increasingly explored the cognitive processes underlying eating disorders (EDs), including anorexia nervosa (AN), bulimia nervosa (BN), binge eating disorder (BED), other specified feeding or eating disorders (OSFEDs), and individuals with higher weight (HW). This critical narrative review focuses on neurocognitive findings derived from mainly experimental tasks to provide a detailed understanding of cognitive functioning across these groups. Where experimental data are lacking, we draw on self-report measures and neuroimaging findings to offer supplementary insights. Method: A search of major databases that prioritized meta-analyses and recent publications (last 10 years) was conducted. Using comprehensive search terms related to EDs, HW, and neurocognition, eligible studies focused on human neurocognitive outcomes (e.g., cognitive flexibility, attentional bias, etc.) published in English were selected. Results: We found that some neurocognitive characteristics, such as cognitive rigidity, impulsivity, emotion processing difficulties, and dysregulated reward processing, appear transdiagnostic, spanning multiple ED subtypes and HW populations. We also revealed neurocognitive features specific to ED subtypes and HW. For instance, individuals with AN demonstrate an enhanced focus on detail, and BN and BED are characterized by a pronounced attentional bias toward food-related stimuli. In individuals with HW, cognitive processes underpin behaviours associated with overeating and weight gain. Conclusions: These findings highlight the critical importance of understanding both the unique and shared neurocognitive patterns across ED subtypes and HW populations. By identifying transdiagnostic factors, such as cognitive rigidity and reward processing, alongside ED subtype/HW-specific vulnerabilities, researchers and clinicians can develop more nuanced, evidence-based interventions that address the core mechanisms driving disordered eating behaviours.

Changes in resting-state functional connectivity of large-scale brain networks in bulimia nervosa: evidence from causal analysis

Bulimia nervosa (BN) has been observationally linked to the functional connectivity (FC) of large-scale brain networks, but the biological mechanisms remain unclear. This study used two-sample Mendelian randomization (MR) with genetic variations as instrumental variables (IVs) to explore potential causal relationships between FC and BN. Summary data from genome-wide association studies (GWAS) involving 2,564 individuals were analyzed to identify genetically predicted BN. Functional magnetic resonance imaging parameters and materials were sourced from the UK Biobank. The variables underwent independent component analysis processing by the database to generate the final GWAS dataset. Various methods, including MR Pleiotropy RESidual Sum and Outlier, MR Egger, and weighted median, were employed to detect heterogeneity and pleiotropy, with inverse variance weighting serving as the principal estimation method (P < 0.05). The FC imaging-derived phenotypes revealed that BN exerted a causal influence on the FC between large-scale networks, including the visual network, default mode network (DMN), frontoparietal network, somatosensory network (SSN), and ventral attention network. Additionally, BN had a causal impact on the within-network FC of both the DMN and SSN. The study provides evidence that BN leads to further changes in FC patterns within and between large-scale brain networks.

Eating disorders: etiology, risk factors, and suggestions for prevention

PURPOSE OF REVIEW

The incidence of eating disorders has increased worldwide. This narrative review gives an overview of research on etiology and risk factors of eating disorders published in 2022-2024.

RECENT FINDINGS

Eating disorders arise from a complex set of risk factors. The recent increase in incidence of eating disorders can be linked to root causes that include sociocultural pressure to conform to unrealistic and gendered body ideals, rise in obesogenic environments, and the global COVID-19 pandemic. Recent studies have shown that screen time and social media intensify sociocultural pressure to look a certain way. Individual-specific risk factors also increase the likelihood of onset of eating disorders. These include sports, stressful and traumatic life events, family factors, and psychological factors, including disgust sensitivity, aversive experiences, low self-esteem, perfectionism, neuroticism, obsessive-compulsive and impulsive features, and emotional dysregulation. Preexisting mental health conditions, particularly anxiety, depression, and posttraumatic stress disorder, and neurodevelopmental conditions, such as autism and attention-deficit hyperactive disorder, are also associated with increased eating disorder risk. Genetic and biological factors contribute both to risk and resiliency.

SUMMARY

The risk factors of eating disorders are well established. Future studies should focus on increasing resilience and preventive interventions.

Appearance-related cyberbullying and its association with the desire to alter physical appearance among adolescent females

Cyberbullying is associated with various mental health concerns in adolescents, including body dissatisfaction and disordered eating behaviours. However, there is a significant research gap concerning the unique effects of appearance-related cyberbullying (ARC) on adolescent mental health. This study examined the prevalence and psychological consequences of ARC among middle to late adolescent females (aged 14-19 years, Mage = 15.98, N = 336). Participants completed an online survey regarding their experiences of ARC, body image variables, and eating disorder symptomology. Findings indicate the widespread occurrence of ARC among adolescent females, with body shape and size emerging as predominant targets. Experiences of ARC-victimisation positively correlated with increased concerns about body shape, body shame, and eating disorder symptomology. Conversely, experiences of ARC-victimisation were negatively correlated with body esteem and body appreciation. Finally, appearance-related cybervictimisation was significantly associated with adolescent females' desire to pursue appearance alterations through methods such as dieting and exercising, altering self-presentation, and undergoing cosmetic procedures due to perceived experiences of ARC. These findings highlight the urgent need for preventative measures, such as age-appropriate social media policies and health promotion programs that encourage positive online behaviour, and strategies to address the impacts of ARC to protect the mental well-being of adolescent females.

Taking better advantage of the activity-based anorexia model

The lack of specific treatments for anorexia nervosa (AN) is partly driven by an inadequate understanding of the neurobiological drivers of the condition. The activity-based anorexia (ABA) model recapitulates key characteristics of AN in rats and mice, and can be used to understand factors that predispose, maintain, and rescue anorectic behaviour. With the rapidly evolving suite of technologies to manipulate and record neural activity during the development of ABA, we are better placed than ever before to take advantage of this unique biobehavioural model in order to develop and refine novel treatments for AN. This will require a collective effort to bridge research disciplines in order to capitalise on knowledge gains from genetics, neurobiology, metabolism, and cognition.