Reward-related decision making in eating and weight disorders: A systematic review and meta-analysis of the evidence from neuropsychological studies

[Anorexia nervosa: An addiction? Application of the addiction model to eating disorders. A narrative commented review]

OBJECTIVES

Addiction offers a framework for the understanding of eating disorders, particularly those characterized by hyperphagia, with growing interest in food addiction. However, the application of the addiction model to anorexia nervosa remains more controversial. In this commented narrative review, we examine and discuss the addictive features of anorexia nervosa.

METHODS

Commented narrative review of the literature.

RESULTS

Anorexia nervosa could be the consequence of the loss of control of several objects of positive reinforcement: food restriction, physical hyperactivity, and food itself. Craving has been little studied in the field of eating disorders. When investigated, studies mainly focus on food cravings and tend to highlight food cravings that are inversely correlated with the restrictive nature of the disorder. This would thus be less found in anorexia nervosa, in which it is nevertheless reported. The existence of a pre-existing food craving, or its appearance secondary to food restriction, is currently under discussion. In the meantime, the question of a craving for food restriction, underpinned by the gratifying effect of fasting, is raised.

CONCLUSIONS

The management of eating disorders has its place within the addiction care sectors. An integrative approach should be favored, for anorexia nervosa, combining, on the one hand, classic nutritional care, and, on the other hand, care within the framework of addiction treatment. Finally, in people with an eating disorder, the search for an addiction to food, food restriction and physical activity, including a systematic assessment of craving, should be systematized.

Functional alterations in overweight/obesity: focusing on the reward and executive control network

Overweight (OW) and obesity (OB) have become prevalent issues in the global public health arena. Serving as a prominent risk factor for various chronic diseases, overweight/obesity not only poses serious threats to people's physical and mental health but also imposes significant medical and economic burdens on society as a whole. In recent years, there has been a growing focus on basic scientific research dedicated to seeking the neural evidence underlying overweight/obesity, aiming to elucidate its causes and effects by revealing functional alterations in brain networks. Among them, dysfunction in the reward network (RN) and executive control network (ECN) during both resting state and task conditions is considered pivotal in neuroscience research on overweight/obesity. Their aberrations contribute to explaining why persons with overweight/obesity exhibit heightened sensitivity to food rewards and eating disinhibition. This review centers on the reward and executive control network by analyzing and organizing the resting-state and task-based fMRI studies of functional brain network alterations in overweight/obesity. Building upon this foundation, the authors further summarize a reward-inhibition dual-system model, with a view to establishing a theoretical framework for future exploration in this field.

Change in motivational bias during treatment predicts outcome in anorexia nervosa

OBJECTIVE

Reward and punishment sensitivity are known to be altered in anorexia nervosa (AN). Most research has examined these constructs separately although motivated behavior is influenced by considering both the potential for reward and risk of punishment. The present study sought to compare the relative balance of reward and punishment sensitivity in AN versus healthy controls (HCs) and examine whether motivational bias is associated with AN symptoms and treatment outcomes.

METHODS

Adolescents and adults with AN (n = 262) in a partial hospitalization program completed the Eating Disorders Examination Questionnaire (EDE-Q), Behavioral Inhibition System/Behavioral Activation System (BIS/BAS) scales, and Sensitivity to Punishment/Sensitivity to Reward Questionnaire (SPSRQ) at admission and discharge. HCs (HC; n = 90) completed the BIS/BAS and SPSRQ. Motivational Bias Scores were calculated to reflect the dominance of reward versus punishment sensitivity.

RESULTS

Individuals with AN demonstrated significantly greater bias toward punishment sensitivity than HC. In AN, a bias toward punishment was associated with higher EDE-Q Global score at admission. Change in motivational bias during treatment predicted EDE-Q Global scores, but not BMI, at discharge, with greater increases in reward sensitivity or greater decreases in punishment sensitivity during treatment predicting lower eating pathology. Similar findings were observed using the BIS/BAS and SPSRQ.

DISCUSSION

Change in motivational bias during treatment is associated with improved outcomes in AN. However, it appears that much of the change in motivational bias can be attributed to changes in punishment sensitivity, rather than reward sensitivity. Future research should examine the mechanisms underlying punishment sensitivity decreases during treatment.

PUBLIC SIGNIFICANCE

Sensitivity to reward and punishment may be important treatment targets for individuals with anorexia nervosa (AN). To date, most research has considered reward and punishment sensitivity separately, rather than examining their relationship to each other. We found that the balance of reward and punishment sensitivity (i.e., motivational bias) differs between healthy controls and those with AN and that this bias is associated with eating disorder symptoms and treatment outcome.

Greater reliance on model-free learning in adolescent anorexia nervosa: An examination of dual-system reinforcement learning

Alterations in learning and decision-making systems are thought to contribute to core features of anorexia nervosa (AN), a psychiatric disorder characterized by persistent dietary restriction and weight loss. Instrumental learning theory identifies a dual-system of habit and goal-directed decision-making, linked to model-free and model-based reinforcement learning algorithms. Difficulty arbitrating between these systems, resulting in an over-reliance on one strategy over the other, has been implicated in compulsivity and extreme goal pursuit, both of which are observed in AN. Characterizing alterations in model-free and model-based systems, and their neural correlates, in AN may clarify mechanisms contributing to symptom heterogeneity (e.g., binge/purge symptoms). This study tested whether adolescents with restricting AN (AN-R; n = 36) and binge/purge AN (AN-BP; n = 20) differentially utilized model-based and model-free learning systems compared to a healthy control group (HC; n = 28) during a Markov two-step decision-making task under conditions of reward and punishment. Associations between model-free and model-based learning and resting-state functional connectivity between neural regions of interest, including orbitofrontal cortex (OFC), nucleus accumbens (NAcc), putamen, and sensory motor cortex (SMC) were examined. AN-R showed higher utilization of model-free learning compared to HC for reward, but attenuated model-free and model-based learning for punishment. In AN-R only, higher model-based learning was associated with stronger OFC-to-left NAcc functional connectivity, regions linked to goal-directed behavior. Greater utilization of model-free learning for reward in AN-R may differentiate this group, particularly during adolescence, and facilitate dietary restriction by prioritizing habitual control in rewarding contexts.

What can functional brain imaging teach us about remission of type 2 diabetes?

AIMS

With a paradigm shift in attitudes towards type 2 diabetes (T2D), 'weight loss responsive' diabetes is now thought of as a curable disease state. As a result, national programmes are being orchestrated to induce T2D remission soon after diagnosis with aggressive dietary interventions-such as very low-calorie diets (VLCD). However, dietary interventions to achieve weight loss and diabetes remission lack the same long-term sustainability and cardiovascular risk reduction evidence as bariatric surgery. This review aims to explore how brain imaging has contributed to our understanding of human eating behaviours and how neural correlates are affected by T2D.

METHODS

We summarise functional MRI (fMRI) studies looking at human eating behaviour and obesity. We explore how these neural correlates are affected by insulin resistance and T2D itself as well as its different treatment approaches. Finally, we comment on the need for more personalised approaches to maintaining metabolic health and how fMRI studies may inform this.

CONCLUSION

fMRI studies have helped to fashion our understanding of the neurobiology of human appetite and obesity. Improving our understanding of the neural implications of T2D that promote disadvantageous eating behaviours will enable prevention of disease as well as mitigation against a vicious cycle of metabolic dysfunction and associated cognitive complications.

Transdiagnostic considerations of the relationship between reward sensitivity and psychopathological symptoms - a cross-lagged panel analysis

BACKGROUND

Reward sensitivity constitutes a potential key mechanism regarding the etiology and maintenance of mental disorders, especially depression. However, due to a lack of longitudinal studies, the temporal dynamics are not clear yet. Although some evidence indicates that reward processing could be a transdiagnostic mechanism of disorders, these observations could be also a product of comorbidity with depression. This study aimed at investigating the temporal dynamics of reward sensitivity and the course of psychopathological symptoms in a longitudinal investigation, while taking a possible mediating role of depression into account.

METHODS

We conducted a three-wave longitudinal online survey with a 4-week interval. A total of N = 453 participants filled out all three questionnaires. Reward sensitivity was assessed with the Positive Valence System Scale-21 (PVSS-21), depression with the Patient Health Questionnaire (PHQ-9), eating disorder symptoms with the Eating Disorder Examination-Questionnaire-8 (EDE-Q-8), social anxiety with the Mini-social phobia inventory (Mini-SPIN) and alcohol consumption with the Alcohol Use Disorders Identification Test-Consumption (AUDIT-C). Cross-lagged panels and mediation analyses were calculated using path analyses.

RESULTS

Depressive and eating disorder symptoms predicted reward insensitivity at later points in time. Effects were larger from T2 to T3. A bidirectional relationship concerning social anxiety was found. Higher alcohol consumption predicted higher reward sensitivity. Depression at T2 fully mediated the association between psychopathological symptoms at T1 and reward sensitivity at T3 for social anxiety and eating disorder symptoms.

CONCLUSIONS

Our findings imply that reduced reward sensitivity seems to be a consequence rather than an antecedent of psychopathological symptoms. Comorbid depression plays a crucial role in other mental disorders regarding observed hyposensitivity towards rewards. Therefore, our results do not support a transdiagnostic notion of reward sensitivity, but they indicate a potential role of reward sensitivity for symptom persistence.

TRIAL REGISTRATION

The study was preregistered at the Open Science Framework (OSF) ( https://archive.org/details/osf-registrations-6n3s8-v1 ; registration DOI https://doi.org/10.17605/OSF.IO/6N3S8 ).

Dysfunctional decision-making in binge-eating disorder: A meta-analysis and systematic review

Binge-Eating Disorder (BED) involves anticipatory craving and urges, subjective loss-of-control during binge-eating episodes, and post-feeding psychological distress and guilt. Evidence indicates neurocognitive dysfunctions contribute to BED onset, maintenance, and treatment response. However, an integrated understanding of how cognitive processes underpin BED symptomology is lacking. We utilised a multi-stage decision-making model defining ten cognitive processes underpinning Preference Formation, Choice Implementation, Feedback Processing, and Flexibility/Shifting, to comprehensively review research published since 2013. We used preregistered PICOS criteria to assess 1966 articles identified from PubMed, PsycInfo, and Scopus database searches. This yielded 50 studies reporting behavioural cognitive tasks outcomes, comparing individuals with BED to controls with normal and higher weight. Meta-analyses revealed a unique profile of cognitive dysfunctions that spanned all decision-making stages. Significant deficits were evident in Uncertainty Evaluation, Attentional Inhibition, Choice Consistency, and Cognitive Flexibility/Set-shifting. We propose a novel model of dysfunctional decision-making processes in BED and describe their role in binge-eating behaviour. We further highlight the potential for cognitive interventions to target these processes and address the significant treatment gap in BED.

Integrating aspects of affect, reward, and cognition to develop more comprehensive models of binge-eating pathology

Reward-related processes are an increasing focus of eating disorders research. Although evidence suggests that numerous distinct reward processes may contribute to eating pathology (e.g., reward learning and delay discounting), existing etiological models of reward dysfunction tend to focus on only a limited number of reward processes, and frequently lack specificity when identifying the individual reward processes hypothesized to contribute to dysregulated eating behavior. Moreover, existing theories have been limited in their integration of reward-related processes with other demonstrated risk and maintenance factors for eating disorders (e.g., affect and cognition), potentially contributing to underdeveloped models of eating pathology. In this article, we highlight five distinct reward processes with theorized or demonstrated relevance to eating disorders involving binge-eating, followed by a review of two well-established risk/maintenance factors for binge-eating pathology. We then introduce two novel models of binge eating onset and maintenance that integrate these factors (i.e., the Affect, Reward, Cognition models), and discuss methods for testing each of the models in future research. Ultimately, we hope that the proposed models provide a springboard for the continued evolution of more precise and comprehensive theories of reward dysfunction in the eating disorders, as well as the development of novel intervention approaches. PUBLIC SIGNIFICANCE STATEMENT: Eating disorders are associated with abnormalities in multiple domains of reward functioning. However, models of reward dysfunction within the eating disorders have not been well-integrated with prominent models of affect and cognition. This article presents two novel models of onset and maintenance for binge-eating pathology, which attempt to integrate observed reward abnormalities with other affective and cognitive processes implicated in binge-type eating disorders.

Association of minimally processed and ultra-processed food daily consumption with obesity in overweight adults: a cross-sectional study

INTRODUCTION

food type represents higher odds of having obesity (OB), especially in overweight (OW) subjects. Minimally and ultra-processed foods can be associated with the odds of having OB in OW subjects.

OBJECTIVE

to investigate the association of minimally and ultra-processed food consumption with OB in OW adults.

METHODS

we included 15,024 participants (9,618 OW [25.0-29.9 kg/m2], 5,406 OB [≥ 30 kg/m2]) with ages ranging from 18 to 59 years from the 2019 baseline survey of the Surveillance of Risk Factors and Protection for Chronic Diseases by Telephone Survey (VIGITEL, Brazil). Minimally and ultra-processed food daily consumption scores and confounding variables (age, sex, scholarly, physical activity, hypertension, and diabetes) were measured. Binary logistic regression analyzes the association of minimally and ultra-processed food consumption scores with OB (odds ratio [OR]).

RESULTS

minimally processed food consumption score quartiles (1st = 1[food-score/day]; 2nd = 6[food-score/day]; 3rd = 7[food-score/day]; 4th = 8[food-score/day]) presented higher values compared to ultra-processed food (1st = 1[food-score/day]; 2nd = 1[food-score/day]; 3rd = 2[food-score/day]; 4th = 4[food-score/day]). For each score of minimally processed food consumed, there was a -5.9 % odds of OB. Thus, the higher quartile (4th) of minimally processed food consumption score represents less odds of OB (OR: -47.2 %; p < 0.001). Each ultra-processed food score consumed presented odds of 3.7 % of OB. Therefore, higher consumption of ultra-processed food (4th quartile) shows higher odds of OB (OR: +14.8 %; p < 0.001). All associations remained significatively even after being adjusted by the confounders.

CONCLUSION

the consumption scores of minimally processed and ultra-processed foods presented a magnitude capable of impacting OW adults' odds of OB, even when controlled by sociodemographic factors, physical activity, hypertension, and diabetes.

Food-related reward sensitivity across the spectrum of body weight and impulsive eating: Pilot findings from a multi-method approach

Overweight with and without comorbid binge-eating disorder (BED) has been associated with increased reward sensitivity, though evidence is heterogeneous. To disentangle this heterogeneity and gain insights into mechanisms of impaired reward processing, this study applied multi-method neuro-behavioural techniques. Reward sensitivity was investigated in N = 49 participants allocated to three subgroups: overweight individuals with BED (BED+, n = 17), overweight individuals without BED (BED-, n = 15), and normal-weight controls (NWC, n = 17). Applying a free exploration paradigm (food vs. non-food stimuli), eye tracking and electroencephalographic data were gathered. A valid cue before stimulus onset indicated the position of food, and the end points analysed after the cue and stimulus onset were attentional approach, attention allocation, and conflict processing (e.g., conflict between looking at the potentially rewarding food stimulus or not). The effect of negative mood was tested using mood induction. The study's main hypothesis was that individuals with overweight, particularly under negative mood, would have increased food-related reward sensitivity. All participants showed increased food-specific attentional approach (p < .001). BED + allocated more attention to food stimuli than non-food stimuli compared to the healthy control (p = .045). For individuals with overweight but without BED (BED-), results indicate that conflict processing might be prolonged after the stimulus onset (p = .011). No group-specific effect of negative mood was found. Preliminary results in overweight individuals with and without comorbid BED suggest that food stimuli are generally rewarding stimuli, but even more so for participants with binge eating psychopathology. Prolonged conflict processing during the confrontation with competing food and non-food stimuli was solely found in the BED- sample and might indicate a compensation mechanism. Replication is warranted. The multi-method approach seems to be promising to give indications for the development of psychotherapeutic treatment.

Testing reward processing models of obesity using in-the-moment assessments of subjective enjoyment of food and non-food activities

OBJECTIVE

Although altered reward processing is proposed to play a key role in obesity maintenance, the role of food enjoyment and enjoyment of non-food naturally rewarding activities ("non-food enjoyment") in obesity maintenance remains unknown. This study examined how food and non-food enjoyment were associated with baseline body mass index (BMI) and weight loss (WL) following year-long behavioral WL treatment.

METHODS

At baseline, participants (MAge = 51.81; 73.8 % White, N = 279) with overweight/obesity completed a 7-day ecological momentary assessment (EMA) protocol inquiring about pleasure/enjoyment derived from eating and non-food activities over the past few hours. Participants also completed retrospective self-report measures of food/non-food enjoyment. With linear regressions, associations between EMA food/non-food enjoyment and BMI and post-treatment WL were examined. Race was included as a covariate.

RESULTS

EMA and retrospective food/non-food enjoyment measures had modest concordance, providing preliminary psychometric support for the EMA measures. Partially consistent with hypotheses, greater EMA food enjoyment was associated with lower BMI (B = -1.03, p = .01) and with greater WL, though the latter association was not statistically significant (B = 1.15, p = .07). Exploratory analyses suggested that race was associated with food enjoyment (non-White participants had greater food enjoyment than White participants, d = 0.81, p = .005), and that race may have affected associations between food enjoyment and weight outcomes. Associations between non-food enjoyment and weight outcomes were small and nonsignificant (ps > .93).

CONCLUSIONS

Results suggest enjoyment from food, but not from non-food domains, is associated with weight outcomes.

Altered Reinforcement Learning from Reward and Punishment in Anorexia Nervosa: Evidence from Computational Modeling

OBJECTIVES

Anorexia nervosa (AN) is associated with altered sensitivity to reward and punishment. Few studies have investigated whether this results in aberrant learning. The ability to learn from rewarding and aversive experiences is essential for flexibly adapting to changing environments, yet individuals with AN tend to demonstrate cognitive inflexibility, difficulty set-shifting and altered decision-making. Deficient reinforcement learning may contribute to repeated engagement in maladaptive behavior.

METHODS

This study investigated learning in AN using a probabilistic associative learning task that separated learning of stimuli via reward from learning via punishment. Forty-two individuals with Diagnostic and Statistical Manual of Mental Disorders (DSM)-5 restricting-type AN were compared to 38 healthy controls (HCs). We applied computational models of reinforcement learning to assess group differences in learning, thought to be driven by violations in expectations, or prediction errors (PEs). Linear regression analyses examined whether learning parameters predicted BMI at discharge.

RESULTS

AN had lower learning rates than HC following both positive and negative PE (p < .02), and were less likely to exploit what they had learned. Negative PE on punishment trials predicted lower discharge BMI (p < .001), suggesting individuals with more negative expectancies about avoiding punishment had the poorest outcome.

CONCLUSIONS

This is the first study to show lower rates of learning in AN following both positive and negative outcomes, with worse punishment learning predicting less weight gain. An inability to modify expectations about avoiding punishment might explain persistence of restricted eating despite negative consequences, and suggests that treatments that modify negative expectancy might be effective in reducing food avoidance in AN.

Disinhibited Eating and Executive Functioning in Children and Adolescents: A Systematic Review and Meta-Analysis

A growing body of research suggests disinhibited eating and weaker executive function (EF) are two risk factors for pediatric obesity. Emerging brain imaging and behavioral findings support the notion that EF skills impact eating regulation. However, a major gap in the current literature is a synthesis of the association between various EF skills and disinhibited eating patterns across child development. To address this gap, a systematic review and meta-analysis was conducted to examine the effect of EF skills on disinhibited eating behaviors among youth ages 3-18 years old. PubMed and PsychINFO databases were utilized and data from 15 studies with a total sample of 4909 youth were included. A random effects meta-analysis revealed a small negative effect of overall EF skills on disinhibited eating behavior, r = -0.14, p < 0.01. Analysis of individual EF skills found working memory had an overall medium negative effect on disinhibited eating behavior, r = -0.25, p < 0.05. Taken together, findings from this meta-analysis support an inverse relationship between EF abilities and disinhibited eating patterns in children and adolescents, such that poorer EF abilities are associated with higher levels of disinhibited eating. Given the effect on eating behavior, future research is needed to assess whether EF difficulties may be a barrier to effective weight management in youth. Specifically, research is needed to examine whether EF skills may be a key target to consider for effective obesity prevention and treatment in children and adolescents.

Do Overweight People Have Worse Cognitive Flexibility? Cues-Triggered Food Craving May Have a Greater Impact

Background: Overweight people have been revealed to have poor cognitive flexibility. Cognitive flexibility reflects proactive and reactive control abilities. However, the impairment had not been explicitly positioned at the cognitive stage. Therefore, this study provides increased support for impairment of cognitive flexibility due to overweight. Method: The study included 34 overweight and 35 normal-weight participants. They were required to complete the food and flower target AX-continuous performance test (AX–CPT), including the resting-state fMRI and cue-triggered food craving subscales. We compared the performance difference between the two tasks. Furthermore, we investigated whether the cue-triggered food cravings and the corresponding brain regions mediated the effect of overweight on the two control mechanisms. Result: Significant differences were found only in the food target AX-CPT task, where overweight participants performed worse. Cue-triggered food cravings mediated this relationship. Additionally, we found that the brain regions associated with cue-triggered food cravings (bilateral SFG) can completely mediate the relationship between BMI and the z-value of the fat mass index and sensitivity to proactive control. Conclusion: In the food target task, overweight participants performed worse in both control mechanisms. Moreover, we also revealed the potential mechanism by which being overweight might affect the two control mechanisms through cue-triggered food cravings.

Beyond Description and Deficits: How Computational Psychiatry Can Enhance an Understanding of Decision-Making in Anorexia Nervosa

PURPOSE OF REVIEW

Despite decades of research, knowledge of the mechanisms maintaining anorexia nervosa (AN) remains incomplete and clearly effective treatments elusive. Novel theoretical frameworks are needed to advance mechanistic and treatment research for this disorder. Here, we argue the utility of engaging a novel lens that differs from existing perspectives in psychiatry. Specifically, we argue the necessity of expanding beyond two historically common perspectives: (1) the descriptive perspective: the tendency to define mechanisms on the basis of surface characteristics and (2) the deficit perspective: the tendency to search for mechanisms associated with under-functioning of decision-making abilities and related circuity, rather than problems of over-functioning, in psychiatric disorders.

RECENT FINDINGS

Computational psychiatry can provide a novel framework for understanding AN because this approach emphasizes the role of computational misalignments (rather than absolute deficits or excesses) between decision-making strategies and environmental demands as the key factors promoting psychiatric illnesses. Informed by this approach, we argue that AN can be understood as a disorder of excess goal pursuit, maintained by over-engagement, rather than disengagement, of executive functioning strategies and circuits. Emerging evidence suggests that this same computational imbalance may constitute an under-investigated phenotype presenting transdiagnostically across psychiatric disorders. A variety of computational models can be used to further elucidate excess goal pursuit in AN. Most traditional psychiatric treatments do not target excess goal pursuit or associated neurocognitive mechanisms. Thus, targeting at the level of computational dysfunction may provide a new avenue for enhancing treatment for AN and related disorders.

Reward-related decision-making deficits in internet gaming disorder: a systematic review and meta-analysis

AIMS

To estimate the aggregated effect sizes of reward-related decision-making deficits in internet gaming disorder (IGD) and to explore potential moderators on the variability of effect sizes across studies.

DESIGN

Review of peer-reviewed studies comparing reward-related decision-making performance between IGD and control participants identified via PubMed, Web of Science and ProQuest databases. Random-effects modeling was conducted using Hedge's g as the effect size (ES). The effects of decision-making situation, valence, sample type, testing environment, IGD severity and self-reported impulsivity on decision-making differences were examined by moderator analyses.

SETTING

No restrictions on location.

PARTICIPANTS

Twenty-four studies (20 independent samples) were included in the meta-analysis, resulting in 604 IGD and 641 control participants and 35 ESs.

MEASURES

Reward-related decision-making differences between IGD and control groups.

FINDINGS

The overall ES for decision-making deficits in IGD was small (g = -0.45, P < 0.01). The effects were comparable across risky, ambiguous and inter-temporal decision-making. Larger aggregate ESs were identified for pure-gain and mixed compared with pure-loss decision-making. Studies based on clinical and community samples showed similar effects. No significant difference between behavioral studies and those with extra measurements was observed. Decision-making alterations were not closely associated with IGD severity or self-reported impulsivity differences at the study level.

CONCLUSIONS

Internet gaming disorder appears to be consistently associated with reward-related decision-making deficits.

Neuropsychological functioning in adult anorexia nervosa: A meta-analysis

Several studies have conceptualized neuropsychological dysfunction as part of the core pathology and defining behaviors seen in the eating disorder anorexia nervosa (AN). The aim of the current review was to synthesize the differences in neuropsychological test performance between individuals with AN and healthy controls, quantify and explain their heterogeneity. The search and screening procedures resulted in fifty studies that comprised 186 neuropsychological test results. Utilizing random-effects meta-analyses, the results revealed evidence for significant, moderate underperformance in people with AN in overall neuropsychological functioning (g¯ = -0.43, 95 % CI [-0.50, -0.36]). Weighted mean effect sizes ranged from g¯ = -0.53 for visuospatial abilities to g¯ = -0.10 for planning. Study and participant characteristics, including body mass index (BMI) and age, had significant moderator effects, especially on executive function, memory, and visuospatial abilities. The findings from the current study provide an extensive and comprehensive overview of the possible impairments in neuropsychological functioning in adult patients diagnosed with AN.

Attentional and executive functions in children and adolescents with developmental coordination disorder and the influence of comorbid disorders: A systematic review of the literature

Developmental coordination disorder (DCD) is a neurodevelopmental disorder affecting primarily motor skills, but attentional and executive impairments are common in affected individuals. Moreover, the presence of neurodevelopmental comorbidities is frequent in this population, which certainly influences the cognitive profile of the children concerned. Previous studies have reported deficits in visuospatial/nonverbal and planning tasks. This systematic review of the literature aims to determine if impairments can be found in other attentional and executive functions as well. The type of cognitive tasks, the tasks’ modality (verbal/nonverbal), and the influence of comorbid disorders on attentional and executive profiles are systematically considered. Forty-one studies were identified through the PubMed/Medline and PsycINFO databases according to pre-established eligibility criteria. The results reveal weaknesses in inhibitory control, working memory, planning, nonverbal fluency, and general executive functioning in children with DCD. The presence of comorbid disorders seemingly contributes to the verbal working memory difficulties findings. This review contributes to a better understanding of the cognitive impairments in DCD and of the needs of children with this disorder, allowing to optimize practitioners’ therapeutic interventions.

Impulsive behaviors and clinical outcomes following a flexible intensive inpatient treatment for eating disorders: findings from an observational study

PURPOSE

The aim of the study was to assess the differences between impulsive and non-impulsive patients in response to a multidisciplinary intensive inpatient treatment for eating disorders (EDs).

METHODS

320 patients with EDs were consecutively recruited in an eating disorders unit (EDU). They were assessed by clinical interviews and self-reported questionnaires. The treatment was characterized by a patient-centric approach and included both an intensive and comprehensive standardized multidisciplinary program based on cognitive-behavioral therapy and a flexible and personalized component according to the needs and the history of each patient.

RESULTS

Impulsive ED patients showed greater improvement in specific psychopathological areas, in particular: interpersonal sensitivity of Symptom Checklist-90 (SCL-90) (p = 0.007); Eating Disorder Examination Questionnaire (EDE-Q) Global Score (p = 0.009), EDE-Q eating concern (p < 0.001) and EDE-Q shape concern (p = 0.025). The two groups also showed a different pattern on the Body Uneasiness Test, with impulsive patients uniquely showing improvement on Global Severity Index (p = 0.006), body image concern (p = 0.008), compulsive self monitoring (p = 0.002), and weight phobia (p = 0.037).

DISCUSSION

Results support the hypothesis that patients with impulsive behaviors might benefit from treatments characterized by a standardized cognitive behavioral therapy implemented by third-wave interventions according to each patient's clinical profile. Personalized treatment approaches could be an answer to the complexity of ED, addressing individual psychopathology. Further studies are needed to confirm these preliminary findings.

LEVEL OF EVIDENCE

III, cohort or case-control analytic studies.

Executive Functions in Predicting Weight Loss and Obesity Indicators: A Meta-Analysis

While previous studies have suggested that there exists a relationship between obesity and executive function (EF), the mechanisms and causal relationship between them remain unclear. There are important clinical implications of determining whether EF can predict and treat obesity. We conducted a multilevel meta-analysis of randomized controlled trials (RCTs) and longitudinal studies. Specifically, we investigate (a) whether EF interventions have an effect on weight loss, (b) whether baseline EF can be a predictor of future weight loss through obesity intervention, and (c) whether early-life EF can predict future weight loss. Eight RCTs and 17 longitudinal studies with a total of 11,393 participants were identified. We found that (a) EF interventions may not have an effect on weight loss, (b) baseline inhibition (β = 0.259, p = 0.03) and delay discounting (β = −0.17, p = 0.04) significantly predict future weight loss through obesity intervention, (c) age (F = 13.666, p = 0.005) moderates the relationship between working memory and weight loss through intervention, but not weight status, type of intervention, and percentage of female, and (d) early life inhibition (β = 0.185, p = 0.07) is a marginally significant predictor of future weight loss. Our results seem to support the assumption that the relationship between EF and obesity is not direct, and a higher-order factor, such as genes, may link obesity and EF. Building on the preliminary findings, further studies focusing on EF and obesity are needed in the future.

Decision-Making in Gambling Disorder, Problematic Pornography Use, and Binge-Eating Disorder: Similarities and Differences

Purpose of Review

The present review attempts to provide a comprehensive and critical overview of the neurocognitive mechanisms of gambling disorder (GD), problematic pornography use (PPU) and binge-eating disorder (BED), focusing specifically on decision-making processes.

Recent findings

GD, PPU and BED have been associated with decision-making impairments both under risk and ambiguity. Features such as intelligence, emotions, social variables, cognitive distortions, comorbidities, or arousal may condition decision-making processes in these individuals.

Summary

Impairments in decision-making seem to be a shared transdiagnostic feature of these disorders We also hypothesized the EG relative to the NEG group would demonstrate weaker relationships between problem-gambling severity and health/functioning measures (e.g., substance use) and gambling behaviors (e.g., more time spent gambling) given that EG would account for some of the variance in the relationships between ARPG and these measures. However, there is varying support for the degree to which different features may affect decision-making. Therefore, the study of decision-making processes can provide crucial evidence for understanding addictions and other disorders with addiction-like symptomatology.

Reward Learning Through the Lens of RDoC: a Review of Theory, Assessment, and Empirical Findings in the Eating Disorders

PURPOSE OF REVIEW

Reward-related processes may represent important transdiagnostic factors underlying eating pathology. Using the NIMH Research Domain Criteria as a guide, the current article reviews theories, behavioral and self-report assessments, and empirical findings related to reward learning in the eating disorders.

RECENT FINDINGS

Data from behavioral tasks suggest deficits in reinforcement learning, which may become more pronounced with increasing disorder severity and duration. Self-report data strongly implicate positive eating and thinness/restriction expectancies (an element of reward prediction error) in the onset and maintenance of eating pathology. Finally, self-report measures of habit strength demonstrate relationships with eating pathology and illness duration; however, behavioral task data do not support relationships between eating pathology and a propensity towards general habit development. Existing studies are limited, but provide preliminary support for the presence of abnormal reward learning in eating disorders. Continued research is needed to address identified gaps in the literature.

The Mediating Effect of Self-Control on Depression and Tendencies of Eating Disorders in Adolescents

Self-control is very important for the adaptation among adolescents. It is associated with depression and tendencies of eating disorders. This study aimed to investigate the relationship between the two and the mediating role of self-control for adolescents. In total, 1,231 adolescents (11-18 years) participated in this study. Self-control, depression, and tendencies of eating disorders were evaluated using the Dual-Mode of Self-Control Scale (DMSC-S), 11-item Kutcher Adolescent Depression Scale (KADS-11), and Eating Attitudes Test (EAT-26). The correlations among these factors were analyzed using mediating effect models. Girls had higher scores on the both subscales (impulse system and control system) of DMSC-S (P < 0.001). Those between 15-18 years had higher scores on impulse system than those between 11-14 years (P < 0.001). A significant mediating effect (12.8%) of the impulse system was observed between depression and tendencies of eating disorders in adolescents.

Exploring Neural Mechanisms Related to Cognitive Control, Reward, and Affect in Eating Disorders: A Narrative Review of FMRI Studies

Studies using functional magnetic resonance imaging (fMRI) have contributed to our understanding of possible neural abnormalities among individuals with eating disorders. Many of these studies have focused on three domains: 1) cognitive control, 2) reward processing, and 3) affective processing. This review attempts to summarize the recent fMRI findings across these domains among the most well-characterized eating disorders: anorexia nervosa (AN), bulimia nervosa (BN), and binge eating disorder (BED). Though the literature is a bit murky, a few major themes have emerged. Cognitive control systems are affected among individuals across eating disorder diagnoses, but effects seem least pronounced in AN. Specifically, individuals with all eating disorders appear to show decreased prefrontal activation during cognitive control, but there is less evidence in AN linking decreased prefrontal activation with behavior. There is some evidence that the reinforcing value of food is reduced in AN, but individuals with BN and BED show hyperactivation to rewarding food-related stimuli, suggesting the reinforcing value of food may be enhanced. However, more complex reward processing paradigms show that individuals with BN and BED exhibit hypoactivation to reward anticipation and provide mixed results with regards to reward receipt. There are fewer neuroimaging findings related to affective processing, yet behavioral findings suggest affective processing is important in understanding eating disorders. Though the extant literature is complicated, these studies represent a foundation from which to build and provide insight into potential neurobiological mechanisms that may contribute to the pathophysiology of eating disorders.

Depressive symptoms rather than executive functioning predict group cognitive behavioural therapy outcome in binge eating disorder

Executive functions play an important role in mediating self-control and self-regulation. It has been suggested that the inability to control eating in Binge Eating Disorder (BED) may indicate inefficiencies in executive functioning. This study investigated whether executive functioning predicted cognitive behavioural therapy outcome in BED while accounting for other possible predictors: depressive symptoms, interpersonal factors, eating disorder psychopathology, and self-esteem. Executive functioning and other predictors were assessed in 91 patients with BED by means of neuropsychological tests and questionnaires at baseline. Eating disorder (ED) symptoms were assessed during treatment at variable time points. Potential predictor variables were investigated using multivariate Cox regression models. Recovery was defined by means of two different indicators based on the Eating Disorder Examination-Questionnaire: (a) showing a 50% reduction in baseline symptom ED severity and/or reaching the clinical significance cut-off; and (b) achieving abstinence of objective binge eating. Severity of depressive symptoms was a significant predictor for outcome on both indicators. Patients with no or mild depressive symptoms recovered faster (i.e., 50% reduction in ED symptoms and abstinence of objective binge eating) than those with severe depressive symptoms, which is in line with previous studies. Executive functioning was not related to treatment outcome in this study.

Core Neuropsychological Measures for Obesity and Diabetes Trials: Initial Report

Obesity and diabetes are known to be related to cognitive abilities. The Core Neuropsychological Measures for Obesity and Diabetes Trials Project aimed to identify the key cognitive and perceptual domains in which performance can influence treatment outcomes, including predicting, mediating, and moderating treatment outcome and to generate neuropsychological batteries comprised of well-validated, easy-to-administer tests that best measure these key domains. The ultimate goal is to facilitate inclusion of neuropsychological measures in clinical studies and trials so that we can gather more information on potential mediators of obesity and diabetes treatment outcomes. We will present the rationale for the project and three options for the neuropsychological batteries to satisfy varying time and other administration constraints. Future directions are discussed. Preprint version of the document is available at https://osf.io/preprints/nutrixiv/7jygx/.

The psychology of obesity: An umbrella review and evidence-based map of the psychological correlates of heavier body weight

Psychological factors may explain why some people develop obesity and others remain a normal weight during their life course. We use an umbrella review approach to build an evidence-based map of the psychological correlates of heavier body weight. Synthesising findings from 42 meta-analyses that have examined associations between psychological factors and heavier body weight, we assessed level of evidence for a range of cognitive, psychosocial and mental health individual difference factors. There is convincing evidence that impaired mental health is associated with heavier body weight and highly suggestive evidence that numerous cognitive factors are associated with heavier body weight. However, the relatively low methodological quality of meta-analyses resulted in lower evidential certainty for most psychosocial factors. Psychological correlates of heavier body weight tended to be small in statistical size and on average, people with obesity were likely to be more psychologically similar than different to people with normal weight. We consider implications for understanding the development of heavier body weight and identifying effective public health interventions to reduce obesity.

Cognitive improvement following weight gain in patients with anorexia nervosa: A systematic review

OBJECTIVE

Anorexia nervosa (AN) has been associated with cognitive impairment. While re-nutrition is one of the main treatment targets, the effect on cognitive impairments is unclear. The aim of this review was to examine whether cognitive functions improve after weight gain in patients with AN.

METHOD

A systematic review was performed following Preferred Reporting Items for Systematic Reviews and Meta-analyses statement guidelines (PROSPERO CRD42019081993). Literature searches were conducted May 20^th , 2019 in PubMed, EMBASE, PsychINFO and Cochrane Library. Pairs of reviewers screened reports independently based on titles/abstracts (N = 6539) and full texts (N = 378). Furthermore, they assessed the quality of reports, including whether practice effects were accounted for.

RESULTS

Twenty-four longitudinal reports were included featuring 757 patients and 419 healthy controls. Six studies examined children and adolescents. Four out of four studies found processing speed to improve above and beyond what could be assigned to practice effects and three out of four studies found that cognitive flexibility was unaffected after weight gain in children and adolescents. Results from studies of adults were inconclusive.

DISCUSSION

The literature on cognitive change in patients with AN following weight gain is sparse. Preliminary conclusions can be made only for children and adolescents, where weight gain appeared to be associated with improved processing speed.

Relating goal-directed behaviour to grazing in persons with obesity with and without eating disorder features

BACKGROUND

Both obesity and eating disorders (ED) have been associated with reductions in purposeful, flexible goal-directed behaviour, and with an overreliance on more rigid habitual behaviour. It is currently unknown whether grazing, an eating style which is common in both conditions, is related to goal-directed behaviour. The current study therefore aimed to relate grazing to goal-directed behaviour in a group of participants with obesity with and without ED features, compared to a healthy-weight control group.

METHODS

Participants (N = 87; 67.8% women, mean age 28.57 years), of whom 19 had obesity and significant eating disorder features, 25 had obesity but without marked eating disorder features, and 43 were age- and sex-matched healthy-weight controls, completed two instrumental learning tasks assessing action-outcome contingency sensitivity and devaluation sensitivity, as well as demographic and eating disorder-related questionnaires. Gamma and Ordinary Least Squares regressions were performed to examine the effect of group and grazing on goal-directed behaviour.

RESULTS

Lower action-outcome contingency sensitivity was found in the group with obesity and with eating disorder features than in the group with obesity but without eating disorder features or in healthy controls. No group differences in devaluation sensitivity were found. A small but significant relationship was found between grazing severity and contingency sensitivity in the group with obesity and eating disorder features, such that increasing grazing severity was associated with less diminished contingency sensitivity.

CONCLUSIONS

There is some indication that in persons with obesity and eating disorder features instrumental behaviour is less flexible and adaptive; furthermore, within this group grazing may represent a goal-directed behaviour, despite unhelpful long-term implications of grazing.

A Randomized Study of Food Pictures-Influenced Decision-Making Under Ambiguity in Individuals With Morbid Obesity

BACKGROUND AND AIMS

In addition to craving responses to salient food cues, the anticipation of short-term rewarding consumption of palatable food may overrun the anticipation of long-term negative consequences of obesity. The present investigation addressed the potential interplay of food cravings and decision-making abilities in individuals with obesity.

METHOD

Study 1 included 107 bariatric surgery candidates with class 2/3 obesity (OB-group) and study 2 included 54 individuals with normal weight/pre-obesity (nonOB-group). In both studies, standardized questionnaires concerning food cravings, food addiction, and psychopathology were administered. A cue-reactivity paradigm was used to measure craving responses toward semi-individualized images of highly palatable, processed food/fruit (appetitive food cues) compared to images of raw vegetables (non-appetitive food cues). Decision-making was measured with a modified computerized version of the Iowa Gambling Task (IGT) with food pictures. Both groups were divided into two subgroups that were randomized to different IGT conditions. In one IGT condition the advantageous IGT card decks were covered by pictures of palatable, processed food or fruit and the disadvantageous decks by images of raw vegetables (= congruent condition), and in the other IGT condition vice versa.

RESULTS

Participants in the OB-group admitted on average higher craving responses toward palatable, processed food or fruit cues compared to pictures of raw vegetables. This was not the case in the nonOB-group. Contrary to our hypothesis, decision-making performance in both groups was worse when pictures of palatable, processed food or fruit were associated with advantageous IGT card decks compared to performance when those pictures were linked to the disadvantageous decks. The interference effect of food pictures processing on advantageous decision-making has been observed particularly in those individuals of the OB-group who exhibited high craving responses toward palatable, processed food cues or high levels of food addiction.

DISCUSSION

The results indicate that food pictures processing interferes with decision-making, regardless of weight status. Opposed to the hypothesis, stronger tendencies to avoid than to approach pictures presenting processed, tasty food were observed. Further research should examine how cognitive avoidance tendencies toward processed, high energy food and approach tendencies toward healthy food can be transferred to real life situations.

Somatic symptoms and binge eating in women's daily lives

OBJECTIVE

The present study aimed to determine whether the momentary severity of women's somatic symptoms was concurrently and prospectively associated with their engagement in binge eating in naturalistic settings.

METHOD

Thirty women (M_age = 34.13, SD = 13.92) who had engaged in binge eating at least once over the month prior to study entry completed a 14-day ecological momentary assessment (EMA) protocol. During each of the 14 days, participants received five semi-random surveys via text message that assessed momentary somatic symptom severity (i.e., headaches, stomachaches/pain, chest/heart pain, faintness/dizziness, shortness of breath, fatigue) and disordered eating behaviors. Generalized estimating equations were used to determine whether momentary somatic symptoms were concurrently and prospectively (i.e., by participants' next assessment) associated with the occurrence of binge eating behavior, while controlling for age and body mass index.

RESULTS

At the within-person level, more severe stomachaches/pain, faintness/dizziness, shortness of breath, and fatigue were concurrently associated with an increased likelihood of engaging in binge eating. Further, at the between-person level, more severe stomachaches/pain, chest/heart pain, shortness of breath, and fatigue in general were associated with binge eating across the EMA protocol. Momentary stomachache/pain severity also prospectively predicted women's engagement in binge eating behavior at the next assessment.

CONCLUSIONS

The present results provide initial evidence that multiple somatic symptoms may serve as momentary correlates or proximal antecedents of binge eating behavior in women's daily lives. Somatic symptoms may consequently prove useful to target in eating disorder treatments, perhaps via interoceptive exposure interventions.

Increased anticipatory brain response to pleasant touch in women remitted from bulimia nervosa

Bulimia nervosa (BN) is characterized by affective instability and dysregulated behaviors (binge eating, fasting, self-induced vomiting) that disrupt bodily homeostasis. Mechanisms underlying dysregulation in BN are unclear, although altered reward responsivity, anticipatory processing of environmental cues, and interoception (detection and integration of body-state signals to regulate behavior) have been implicated in BN pathophysiology. We aimed to determine whether BN is associated with ineffectively predicting body state or integrating predicted experience with actual experience by examining neural response to anticipation and experience of affective touch, a pleasant interoceptive stimulus that acts on sensory and emotional systems to guide behavior. During fMRI, we administered soft strokes to the palm and forearm in women remitted from BN (RBN; N = 23) and control women (CW; N = 25). A Group (RBN/CW) × Condition (anticipation/touch) interaction was found in the right dorsal caudate; both CW and RBN had increased activation during touch compared with anticipation, with RBN demonstrating marginally greater anticipatory response than CW. For RBN, those individuals who showed greater anticipatory response in the dorsal caudate also reported higher levels of harm avoidance. RBN individuals relative to CW showed greater activation in left putamen and insula during the anticipation but not when experiencing an affective touch. This increase during anticipation rather than the actual experience of the affective touch is consistent with a top-down preparatory process which is associated with harm avoidance and is similar to what has been observed in anxious individuals. This aberrant signal integration could disrupt feedback processing, serving to maintain disordered behavior.

Case report: cognitive performance in an extreme case of anorexia nervosa with a body mass index of 7.7

BACKGROUND

Studies show that adult patients with anorexia nervosa display cognitive impairments. These impairments may be caused by illness-related circumstances such as low weight. However, the question is whether there is a cognitive adaptation to enduring undernutrition in anorexia nervosa. To our knowledge, cognitive performance has not been assessed previously in a patient with anorexia nervosa with a body mass index as low as 7.7 kg/m2.

CASE PRESENTATION

We present the cognitive profile of a 35-year-old woman with severe and enduring anorexia nervosa who was diagnosed at the age of 10 years. She was assessed with a broad neuropsychological test battery three times during a year. Her body mass index was 8.4, 9.3, and 7.7 kg/m², respectively. Her general memory performance was above the normal range and she performed well on verbal and design fluency tasks. Her working memory and processing speed were within the normal range. However, her results on cognitive flexibility tasks (set-shifting) were below the normal range.

CONCLUSIONS

The case study suggests that it is possible to perform normally cognitively despite extreme and chronic malnutrition though set-shifting ability may be affected. This opens for discussion whether patients with anorexia nervosa can maintain neuropsychological performance in spite of extreme underweight and starvation.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02502617. Registered 20 July 2015.

Exploring Changes in Event-Related Potentials After a Feasibility Trial of Inhibitory Training for Bulimia Nervosa and Binge Eating Disorder

In a feasibility trial comparing two forms of combined inhibitory control training and goal planning (i.e., food-specific and general) among patients with bulimia nervosa (BN) and binge eating disorder (BED), we found evidence of symptomatic benefit, with stronger effects among participants receiving a food-specific intervention. The aim of the present study was to examine changes in behavioral outcomes and event-related potentials (ERPs; N2 and P3 amplitudes) from baseline to post-intervention that might suggest the mechanisms underpinning these effects. Fifty-five participants completed go/no-go tasks during two electroencephalography (EEG) sessions, at baseline and post-intervention. The go/no-go task included "go" cues to low energy-dense foods and non-foods, and "no-go" cues to high energy-dense foods and non-foods. Datasets with poor signal quality and/or outliers were excluded, leaving 48 participants (N = 24 BN; N = 24 BED) in the analyses. Participants allocated to the food-specific, compared to the general intervention group, showed significantly greater reductions in reaction time to low energy-dense foods, compared to non-foods, by post-intervention. Commission errors significantly increased from baseline to post-intervention, regardless of stimulus type (food vs. non-food) and intervention group (food-specific vs. general). There were no significant changes in omission errors. P3 amplitudes to "no-go" cues marginally, but non-significantly, decreased by post-intervention, but there was no significant interaction with stimulus type (high energy-dense food vs. non-food) or intervention group (food-specific vs. general). There were no significant changes in N2 amplitudes to "no-go" cues, N2 amplitudes to "go" cues, or P3 amplitudes to "go" cues from baseline to post-intervention. Training effects were only marginally captured by these event-related potentials. We discuss limitations to the task paradigm, including its two-choice nature, ease of completion, and validity, and give recommendations for future research exploring ERPs using inhibitory control paradigms.

Negative Social Evaluation Impairs Executive Functions in Adolescents With Excess Weight: Associations With Autonomic Responses

BACKGROUND

Adolescents with excess weight suffer social stress more frequently than their peers with normal weight.

PURPOSE

To examine the impact of social stress, specifically negative social evaluation, on executive functions in adolescents with excess weight. We also examined associations between subjective stress, autonomic reactivity, and executive functioning.

METHODS

Sixty adolescents (aged 13-18 years) classified into excess weight or normal weight groups participated. We assessed executive functioning (working memory, inhibition, and shifting) and subjective stress levels before and after the Trier Social Stress Task (TSST). The TSST was divided into two phases according to the feedback of the audience: positive and negative social evaluation. Heart rate and skin conductance were recorded.

RESULTS

Adolescents with excess weight showed poorer executive functioning after exposure to TSST compared with adolescents with normal weight. Subjective stress and autonomic reactivity were also greater in adolescents with excess weight than adolescents with normal weight. Negative social evaluation was associated with worse executive functioning and increased autonomic reactivity in adolescents with excess weight.

CONCLUSIONS

The findings suggest that adolescents with excess weight are more sensitive to social stress triggered by negative evaluations. Social stress elicited deterioration of executive functioning in adolescents with excess weight. Evoked increases in subjective stress and autonomic responses predicted decreased executive function. Deficits in executive skills could reduce cognitive control abilities and lead to overeating in adolescents with excess weight. Strategies to cope with social stress to prevent executive deficits could be useful to prevent future obesity in this population.

Contribution of executive functions to eating behaviours in obesity and eating disorders

BACKGROUND

Patients with eating disorders (ED) or obesity show difficulties in tasks assessing decision-making, set-shifting abilities and central coherence.

AIMS

The aim of this study was to explore executive functions in eating and weight-related problems, ranging from restricting types of ED to obesity.

METHOD

Two hundred and eighty-eight female participants (75 with obesity; 149 with ED: 76 with restrictive eating, 73 with bingeing-purging symptoms; and 64 healthy controls) were administered the Wisconsin Card Sorting Test, the Iowa Gambling Task, and the Group Embedded Figures Test to assess set-shifting, decision-making and central coherence, respectively.

RESULTS

Participants with either obesity or ED performed poorly on tests measuring executive functioning compared with healthy controls, even after controlling for age and intelligence. Both participants with obesity and participants with ED showed a preference for global information processing.

CONCLUSIONS

The findings suggest that treatments for obesity and ED would benefit from addressing difficulties in cognitive functioning, in addition to the more evident clinical symptoms related to eating, body weight and shape.

Strengthened Default Mode Network Activation During Delay Discounting in Adolescents with Anorexia Nervosa After Partial Weight Restoration: A Longitudinal fMRI Study

The capacity of patients with anorexia nervosa (AN) to resist food-based rewards is often assumed to reflect excessive self-control. Previous cross-sectional functional magnetic resonance imaging (fMRI) studies utilizing the delay discounting (DD) paradigm, an index of impulsivity and self-control, suggested altered neural efficiency of decision-making in acutely underweight patients (acAN) and a relative normalization in long-term, weight-recovered individuals with a history of AN (recAN). The current longitudinal study tested for changes in functional magnetic resonance imaging (fMRI) activation during DD associated with intensive weight restoration treatment. A predominately adolescent cohort of 22 female acAN patients (mean age—15.5 years) performed an established DD paradigm during fMRI at the beginning of hospitalization and again after partial weight restoration (≥12% body mass index (BMI) increase). Analyses investigated longitudinal changes in both reward valuation and executive decision-making processes. Additional exploratory analyses included comparisons with data acquired in aged-matched healthy controls (HC) as well as probes of functional connectivity between empirically identified nodes of the “task-positive” frontoparietal control network (FPN) and “task-negative” default-mode network (DMN). While treatment was not associated with changes in behavioral DD parameters or activation, specific to reward processing, deactivation of the DMN during decision-making was significantly less pronounced following partial weight restoration. Strengthened DMN activation during DD might reflect a relative relaxation of cognitive overcontrol or improved self-referential, decision-making. Together, our findings present further evidence that aberrant decision-making in AN might be remediable by treatment and, therefore, might constitute an acute effect rather than a core trait variable of the disorder.

Intact value-based decision-making during intertemporal choice in women with remitted anorexia nervosa? An fMRI study

BACKGROUND

Extreme restrictive food choice in anorexia nervosa is thought to reflect excessive self-control and/or abnormal reward sensitivity. Studies using intertemporal choice paradigms have suggested an increased capacity to delay reward in anorexia nervosa, and this may explain an unusual ability to resist immediate temptation and override hunger in the long-term pursuit of thinness. It remains unclear, however, whether altered delay discounting in anorexia nervosa constitutes a state effect of acute illness or a trait marker observable after recovery.

METHODS

We repeated the analysis from our previous fMRI investigation of intertemporal choice in acutely underweight patients with anorexia nervosa in a sample of weight-recovered women with anorexia nervosa (n = 36) and age-matched healthy controls (n = 36) who participated in the same study protocol. Follow-up analyses explored functional connectivity separately in both the weight-recovered/healthy controls sample and the acute/healthy controls sample.

RESULTS

In contrast to our previous findings in acutely underweight patients with anorexia nervosa, we found no differences between weight-recovered patients with anorexia nervosa and healthy controls at either behavioural or neural levels. New analysis of data from the acute/healthy controls sample sample revealed increased coupling between dorsal anterior cingulate cortex and posterior brain regions as a function of decision difficulty, supporting the hypothesis of altered neural efficiency in the underweight state.

LIMITATIONS

This was a cross-sectional study, and the results may be task-specific.

CONCLUSION

Although our results underlined previous demonstrations of divergent temporal reward discounting in acutely underweight patients with anorexia nervosa, we found no evidence of alteration in patients with weight-recovered anorexia nervosa. Together, these findings suggest that impaired valuebased decision-making may not constitute a defining trait variable or “scar” of the disorder.

IMPULS: Impulsivity-Focused Group Intervention to Reduce Binge Eating Episodes in Patients with Binge Eating Disorder - A Randomised Controlled Trial

BACKGROUND

Impulsivity is a risk factor for binge eating disorder, and binge eating (BE) equates to impulsive eating behaviour. Hence, we developed IMPULS, a cognitive behavioural group intervention focusing on impulsive eating.

METHODS

We randomised 41 patients to the IMPULS group and 39 to the control group. The IMPULS group participated in the IMPULS treatment, while both groups completed weekly self-observations. We compared both groups concerning BE episodes in the past 4 weeks at the end of treatment (primary outcome). As secondary outcomes, we investigated eating pathology, depression, general impulsivity and body mass index (BMI) at the end of treatment and in a 3-month follow-up.

RESULTS

The primary outcome failed, because BE episodes in the past 4 weeks were reduced in both groups at the end of treatment. At follow-up, the IMPULS group showed further improvement, contrary to the control group. The BE days/episodes in the 2 months before were overall reduced in both groups. Eating pathology was reduced in the IMPULS group at the end of treatment and partly in both groups at the follow-up. Depression was only reduced in the IMPULS group. General impulsivity and BMI did not change.

CONCLUSIONS

The IMPULS study has a negative primary outcome. However, secondary outcomes indicate that the IMPULS treatment might be promising, as BE, eating pathology and depression were reduced in the IMPULS group. The initially reduced BE in the control group might represent a short-term effect from the self-observations. General impulsivity and BMI might need a longer time or more intensive treatment to change.

Scrutinizing Domains of Executive Function in Binge Eating Disorder: A Systematic Review and Meta-Analysis

BACKGROUND

Cognitive deficits are implicated in theoretical explanatory models for binge eating disorder (BED). Furthermore, evidence suggest that alterations in executive function may underlie symptoms in BED. The current systematic review and meta-analysis provides an update on executive functioning in individuals with BED.

METHODS

Literature searches (up to November 2019) were conducted in electronic databases combining binge eating or BED with executive functions. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement guidelines was used. Studies of any design comparing adults with BED with those without BED in executive function domains were selected. Methodological quality of studies was based on the Newcastle-Ottawa scale.

RESULTS

Of 1,983 citations identified, 28 case-control studies met inclusion criteria for this review. Six meta-analyses that examined four domains (decision-making, cognitive flexibility, inhibitory control, and working memory) were conducted. The only meta-analysis to show a significant difference in executive functioning between BED and obese controls was working memory (SMD = 0.32, 95% IC: -0.60, -0.03; p = 0.028), with an effect size of small magnitude. Qualitative inspection of the literature indicated mixed findings for control inhibition, decision making and cognitive flexibility in individuals with BED compared to controls (obese or normal weight). In addition, people with BED showed poorer problem solving performance, but similar planning abilities to obese controls.

CONCLUSIONS

Individuals with BED were found to show worse performance on working memory tasks compared to obese individuals without the disorder. The findings did not provide definitive evidence of alterations in other aspects of executive functioning. Interest in executive functioning in people with BED is increasing but is limited by insufficient data from small studies with varied methodology. Future studies should focus on using similar tests and outcome measures, in order to enable more pertinent comparisons across studies.

Combining cognitive bias modification training (CBM) and transcranial direct current stimulation (tDCS) to treat binge eating disorder: study protocol of a randomised controlled feasibility trial

INTRODUCTION

Binge eating disorder (BED) is a common mental disorder, closely associated with obesity. Existing treatments are only moderately effective with high relapse rates, necessitating novel interventions. This paper describes the rationale for, and protocol of, a feasibility randomised controlled trial (RCT), evaluating the combination of transcranial direct current stimulation (tDCS) and a computerised cognitive training, namely approach bias modification training (ABM), in patients with BED who are overweight or obese. The aim of this trial is to obtain information that will guide decision-making and protocol development in relation to a future large-scale RCT of combined tDCS+ABM treatment in this group of patients, and also to assess the preliminary efficacy of this intervention.

METHODS AND ANALYSIS

66 participants with Diagnostic and Statistical Manual-5 diagnosis of BED and a body mass index (BMI) of ≥25 kg/m² will be randomly allocated to one of three groups: ABM+real tDCS; ABM+sham tDCS or a wait-list control group. Participants in both intervention groups will receive six sessions of ABM+real/sham tDCS over 3 weeks; engaging in the ABM task while simultaneously receiving bilateral tDCS to the dorsolateral prefrontal cortex. ABM is based on an implicit learning paradigm in which participants are trained to enact an avoidance behaviour in response to visual food cues. Assessments will be conducted at baseline, post-treatment (3 weeks) and follow-up (7 weeks post-randomisation). Feasibility outcomes assess recruitment and retention rates, acceptability of random allocation, blinding success (allocation concealment), completion of treatment sessions and research assessments. Other outcomes include eating disorder psychopathology and related neurocognitive outcomes (ie, delay of gratification and inhibitory control), BMI, other psychopathology (ie, mood), approach bias towards food and surrogate endpoints (ie, food cue reactivity, trait food craving and food intake).

ETHICS AND DISSEMINATION

This study has been approved by the North West-Liverpool East Research Ethics Committee. Results will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ISRCTN35717198.

Bidirectional Associations between Obesity and Cognitive Function in Midlife Adults: A Longitudinal Study

The links between obesity and cognition remain equivocal due to a variety of methodological limitations with current research, such as an overreliance on body mass index (BMI) as a measure of obesity, the use of cross-sectional designs, and inadequate specification over the domains of cognitive function to be examined. To address these issues, we used data from the Cognitive Project of the National Survey of Midlife Development in the United States, a large-scale, longitudinal dataset on non-institutionalized midlife adults (N = 2652), which enabled us to examine the long-term bidirectional relations between obesity and two latent factors of cognition-executive function and episodic memory-while controlling for potential confounds. Results showed that, over a span of nine years, an increase in obesity in Time 1 is associated with a decline in episodic memory in Time 2 (but not executive function), while an increase in executive function in Time 1 (but not episodic memory) is associated with a reduction in obesity in Time 2. These results were elucidated when obesity was indexed with waist-to-hip ratio but not with BMI. Our findings highlight important directions for further research, in particular the use of more valid obesity indices and a greater focus on the bidirectional effects between obesity and cognition.

The Role of Self-Control and the Presence of Enactment Models on Sugar-Sweetened Beverage Consumption: A Pilot Study

The objective of the present research was to investigate associations of dispositional and momentary self-control and the presence of other individuals consuming SSBs with the consumption frequency of sugar-sweetened beverages (SSBs) in a multi-country pilot study. We conducted an Ambulatory Assessment in which 75 university students (52 females) from four study sites carried smartphones and received prompts six times a day in their everyday environments to capture information regarding momentary self-control and the presence of other individuals consuming SSBs. Multilevel models revealed a statistically significant negative association between dispositional self-control and SSB consumption. Moreover, having more self-control than usual was only beneficial in regard to lower SSB consumption frequency, when other individuals consuming SSBs were not present but not when they were present. The findings support the hypothesis that self-control is an important factor regarding SSB consumption. This early evidence highlights self-control as a candidate to design interventions to promote healthier drinking through improved self-control.

Alterations in serotonin transporter and body image-related cognition in anorexia nervosa

The serotonin system has been implicated in the pathophysiology of anorexia nervosa (AN). A recent report proposed that body image distortion (BID), a core symptom of AN, may relate to abnormalities of the serotonin system, especially the serotonin transporter (5HTT). Positron emission tomography (PET) studies of underweight patients with active AN reported alterations in serotonin receptors, but not 5HTT. Here, we aimed to disclose the clinicopathophysiology of AN by focusing on 5HTT and cognitive functions, including BID, in groups with active AN. Twenty-two underweight female patients with AN (12 restricting-type AN (ANR); 10 binge-eating/purging-type AN (ANBP)) and 20 age-matched healthy female subjects underwent PET with a 5HTT radioligand [¹¹C]DASB. The binding potential (BP_ND) of [¹¹C]DASB was estimated semiquantitatively, and clinical data from Raven's colored progressive matrices for general intelligence, the Stroop test for focused attention, the Iowa gambling task for decision making and a dot-probe task designed for BID were compared with the levels of BP_ND in different groups. [¹¹C]DASB BP_ND was significantly decreased in the medial parietal cortex in patients with AN and in the dorsal raphe in patients with ANR compared with healthy subjects (p < .05 corrected). Patients with ANR showed a significantly negative correlation between [¹¹C]DASB BP_ND in the dorsal raphe and performance on the dot-probe task (p < .05 corrected). While reduced 5HTT in the medial parietal cortex (the somatosensory association area) is pathophysiologically important in AN in general, additional 5HTT reduction in the dorsal raphe as seen in ANR is implicated for the clinicopathophysiological relevance.

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5HTT decreased in the parietal cortex in patients with AN.

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5HTT decreased in the parietal cortex in patients with ANBP.

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5HTT decreased in the parietal cortex and the dorsal raphe in patients with ANR.

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Patients with AN were poor at responding to the test for body image distortion (BID).

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5HTT in the dorsal raphe was associated with cognitive performance of BID.

Food cue reactivity in food addiction: A functional magnetic resonance imaging study

BACKGROUND

While neuroimaging studies have revealed that reward dysfunction may similarly contribute to obesity and addiction, no prior studies have examined neural responses in individuals who meet the "clinical" food addiction phenotype.

METHODS

Women (n = 44) with overweight and obesity, nearly half of whom (n = 20) met criteria for moderate-to-severe Yale Food Addiction Scale 2.0 (YFAS 2.0) food addiction, participated in a functional magnetic resonance imaging cue reactivity task. Participants viewed images of highly processed foods, minimally processed foods, and household objects while thinking about how much they wanted each item. Differences in neural responses by YFAS 2.0 food addiction to highly processed and minimally processed food cues were investigated.

RESULTS

There was a significant interaction between participant group and neural response in the right superior frontal gyrus to highly versus minimally processed food cues (r = 0.57). Individuals with YFAS 2.0 food addiction exhibited modest, elevated responses in the superior frontal gyrus for highly processed food images and more robust, decreased activations for minimally processed food cues, whereas participants in the control group showed the opposite responses in this region. Across all participants, the household items elicited greater activation than the food cues in regions associated with interoceptive awareness and visuospatial attention (e.g., insula, inferior frontal gyrus, inferior parietal lobe).

CONCLUSIONS

Women with overweight or obesity and YFAS 2.0 food addiction, compared to those with only overweight or obesity, exhibited differential responses to highly and minimally processed food cues in a region previously associated with cue-induced craving in persons with a substance-use disorder. Overall, the present work provides further support for the utility of the food addiction phenotype within overweight and obesity.

The influence of depressive symptoms on executive functioning in binge eating disorder: A comparison of patients and non-obese healthy controls

Executive functions are a set of cognitive processes that are necessary for the cognitive control of behavior. They play a role in mediating self-control, self-regulation and decision-making. It has been suggested that the inability to control eating behavior in binge eating disorder (BED) may indicate deficits in executive functioning. This may be worsened by depressive symptoms. The aim of the present study was to compare executive functioning of patients with BED and no-to-mild depressive symptoms (n = 25), patients with BED and moderate-to-severe depressive symptoms (n = 66), and healthy controls (Body Mass Index <30) (n = 56), matched on age, educational level and gender. The participants were assessed by means of neuropsychological tests and questionnaires. The neuropsychological tests did not show significant differences in executive functioning between the groups. However, eating disorder psychopathology and depressive symptoms are associated with self-reported difficulties in executive functioning in daily life. A self-report questionnaire which evaluates the functional, real-world impact of executive dysfunction expressed in everyday activities seems to be more useful in this population than neuropsychological tests. This study highlights the importance of taking depressive symptoms into account when studying executive functioning in patients with (binge) eating disorders.