Binges and Neural Variability

Study Overview
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Brief Summary
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People who suffer from binge eating disorder experience recurrent episodes of binge eating.During these episodes, they consume an unusually large amount of food in a short amount of time and experience loss of control over eating. However, why such binge eating episodes occur is still largely unknown. This makes it difficult to develop targeted treatments. In this project, the experimenters are investigating the brain mechanisms that give rise to the disorder. They hypothesize that the binge eating episodes are due to an increased variability in reward processing, which they will assess repeatedly over days. They will test this hypothesis using mathematical models based on behavioural and MRI measurements that are related to the processing of rewards.

Official Title
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What is Driving the Binge in Binge Eating Disorder? Variability in Brain Response to Reward and the Escalation of Consumption

Conditions
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Binge-Eating Disorder

Intervention / Treatment
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* Diagnostic Test: fMRI


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Binge eating disorder diagnosis Subsyndromal binge eating (control) Exclusion Criteria: high risk of suicide co-occurring psychotic, bi-polar disorders, alcohol/substance dependence within the past six months lack of capacity for consent medical disorders that would affect weight and ability to participate insufficient German language skills (assessment will be in German) taking medication that would affect weight MRI exclusion criteria irremovable metal attached to the body (e.g. piercings) irremovable medical devices (e.g. pacemakers) any trauma or surgery which may have left ferromagnetic material in the body large tattoos pregnancy claustrophobia

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 69 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

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 (BED) patients<br>Individuals with BED diagnosis. | Diagnostic Test: fMRI<br>* (Imaging while) performing reward related tasks.<br>|
| non-BED controls<br>Individuals that do not experience binges | Diagnostic Test: fMRI<br>* (Imaging while) performing reward related tasks.<br>|
| subsyndromal BED controls<br>individuals that experience binges but do not fulfill the requirements for BED diagnosis. | Diagnostic Test: fMRI<br>* (Imaging while) performing reward related tasks.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Variability in blood-oxygen-level dependent (BOLD) signalling in the NAcc during effort allocation task | Variability of BOLD signal in the nucleus accumbens (NAcc) over time and between trials while performing an effort allocation task. The signal is measured through functional magnetic resonance imaging (fMRI) and variability is determined through model residuals. | 100 min | 
| Trial-to-trial variability in reward seeking in an effort allocation task | Variability of performance is an intra-individual measure, that is defined by the residuals of a linear mixed effects model of trial-to-trial performance on the effort allocation task. | 40 min | 
| Variability in BOLD signalling in the NAcc for food-cue reactivity | Variability of BOLD signal in the NAcc between blocks of food pictures. The signal is measured through fMRI and variability is determined through model residuals. | 15 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Variability in BOLD signalling in the NAcc during non-food-cue reactivity | Variability of BOLD signal in the NAcc between blocks of non-food pictures. The signal is measured through fMRI and variability is determined through model residuals. | 5 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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reward sensitivity, neuroimaging, variability, ecological momentary assessment (EMA)