Pilot Study on the Validity of the Metacognitive Hub Model of Craving in Bulimia Nervosa (BN) and Binge Eating Disorders (BED)

Study Overview
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Brief Summary
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Craving is defined as an irrepressible urge to consume certain products and represents one of the key factors in severe substance use disorders, as illustrated by its recent inclusion as a diagnostic criterion in the most recent fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM 5). However, the pathophysiological models of craving remain debated. The metacognitive hub model, a conceptual, experimental and clinical approach to craving, proposes that craving should be considered as the embedded consequence of the interaction between three components (the reflexive, automatic and interoceptive systems), each of which has an implicit and explicit element. This model links the three components by suggesting that metacognitive abilities, the ability to understand one's own cognitive functioning, may be a skill of individuals that allows them to make the three sub-components explicit or not. To date, the conception of eating disorders is increasingly similar to that of addictive disorders. Indeed, there is growing evidence that the symptomatology of bulimia nervosa and binge eating disorder can be considered in part as an food addiction and would fit the diagnostic criteria of an addictive disorder. Bulimia nervosa is an eating disorder (DSM 5) characterized by a cycle of binge eating and compensatory behaviors such as self-induced vomiting that tend to negate or compensate for the effects of the binge eating. Binge eating disorder (DSM 5) is characterized by a cycle of binge eating, but without the compensatory behaviors seen in bulimia nervosa. In addition, there are common neurological aspects as well as similar cognitions between these eating disorders and addictive disorders. Given the importance of craving in addictive pathology, it seems essential to address this issue in bulimia nervosa and binge eating disorder. The cognitive difficulties of patients with bulimia nervosa and binge eating disorder, which are close to the difficulties observed in patients with addictive behaviors, suggest that the metacognitive hub model could provide a clear and measurable theoretical framework of the different dimensions of craving. The overall objective of this project is to explore the relationship between the level of craving induced by food picture exposure and the level of impairment of the reflexive, automatic, interoceptive, and metacognitive systems in women with bulimia nervosa and binge eating disorder and to compare these impairments according to the nature of the eating disorder (i.e., binge eating versus bulimia nervosa). Our hypotheses are: the induction of food craving will affect the reflexive, automatic, and interoceptive systems of patients with bulimia nervosa and binge eating disorder. the magnitude of the effect of food craving induction on implicit craving and explicit craving will be modulated by the participants' metacognitive abilities.

Official Title
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Pilot Study on the Validity of the Metacognitive Hub Model of Craving in Bulimia Nervosa (BN) and Binge Eating Disorders (BED)

Conditions
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Bulimia Nervosa, Binge-Eating Disorder

Intervention / Treatment
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* Behavioral: Food craving induction


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: have been medically diagnosed with binge eating disorder or bulimia nervosa fluent in french able to consent Exclusion Criteria: co-morbid substance use disorder, pregnancy or breastfeeding

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Binge Eating Disorder<br>Participants with a binge eating disorder (DSM-5 criteria) | Behavioral: Food craving induction<br>* Standardized craving induction procedure will be used, based on exposure to food-related images (https://www.lippc2s.fr/food-cal-pictures/). Craving intensity will be measured by visual analogic scale before and after the induction sequence.<br>|
| Bulimia Nervosa<br>Participants with a bulimia nervosa (DSM-5 criteria) | Behavioral: Food craving induction<br>* Standardized craving induction procedure will be used, based on exposure to food-related images (https://www.lippc2s.fr/food-cal-pictures/). Craving intensity will be measured by visual analogic scale before and after the induction sequence.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Attention Network Test (ANT) | The ANT is a task designed to test three attentional networks in children and adults: alerting, orienting, and executive control | 1 hour (after food craving induction) | 
| Dot Probe Task | To test and measure selective attention | 1 hour (after food craving induction) | 
| Water load task | This task was originally developed to induce gastric distension and assess gastrointestinal symptoms in patients with functional digestive disorders. This task stimulates the stomach using a natural distension stimulus (i.e., water ingestion) and without the complex hormonal response of a caloric meal. | 1 hour (after food craving induction) | 
| Live metacognition | live metacognitive assessment will be done by asking the participants to rate their level of confidence on a visual analog scale ranging from 0% (I just guessed) to 100% (completely confident) for each items. | 1 hour (after food craving induction) | 
| Avoidance/Approach task adapted for food craving | In this task, participants are asked to move a joystick that simulates the movement of the food represented in the image. The joystick movements are accompanied by a zoom effect that increases the illusion of movement. | 1 hour (after food craving induction) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Beck Depression Inventory II (BDI-II) | Minimum score : 0; Maximun score : 63; Higher scores mean a worse outcome. | Baseline | 
| State-Trait Anxiety Inventory (STAI) | The questionnaire includes two scales (20 items) consisting of a total of 40 questions. For each scale the minimum score is 0 and the maximun score is 80. Higher scores mean a worse outcome. | Baseline | 
| Eating Disorder Examination Questionnaire (EDE-Q) | The measure provides four attitudinal subscale scores: Restraint (5 items), Eating Concern (5 items), Shape Concern (8 items), and Weight Concern (5 items). An overall Global score is the mean of the four subscale scores. Responses are on a 7-point ordinal response; minimum score : 0, maximun score: 6; higher scores mean a worse outcome. | Baseline | 
| Food Craving Questionnaire State (FCQ-S) | Minimum : 15; Maximun : 75; Higher scores mean a worse outcome. | Baseline | 
| Food Craving Questionnaire Trait (FCQ-T) | Minimum : 39; Maximun : 234; Higher scores mean a worse outcome. | Baseline | 
| Visual Analogic Scale of craving | It represents a continuous visual progression of craving from one extreme to another, from no craving at all to extreme and uncontrollable craving, with patients stating the intensity of their current craving between these two extremes. | Baseline, at 1 hour (after craving induction), at 3 hours (end of the session_ | 
| Schedule for the Assessment of Insight in Eating Disorders (SAI-ED) | Interview-based scale for the multidimensional assessment of insight in eating disorders. It includes three categories: illness awareness, symptom awareness, and treatment engagement. Minimum score : 0, maximun score: 29; Higher scores mean a better outcome. | Baseline | 
| Difficulties in Emotional Regulation Scale (DERS- 18) | Minimum score : 18, maximun score : 90; Higher scores mean a worse outcome. | Baseline | 
| Attentional Control Scale (ACS) | Minimum score : 20, maximun score : 80; Higher scores mean a better outcome. | Baseline | 
| Body Awareness Questionnaire (BAQ) | Minimum score: 18; Maximun score: 126; Higher scores mean a better outcome. | Baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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craving, addiction, metacognition, neurocognition