Causes, mechanisms and consequences of binge eating: understanding maladaptive reward memory processes in young people who binge eat

1. Motor approach bias to highly palatable foods as assessed by changes in performance on a food Go/No-Go task from pre-manipulation on Day 1 (baseline) to post-intervention on Day ~14 (test). Approach bias is demonstrated by faster ‘go’ responses and more commission errors to binge food images than low-palatability and control images in a Go/No-Go CBM task.
2. Changes in oculomotor approach to highly palatable foods as assessed by eyetracking in dot-probe/ attentional bias task, performed pre-intervention on Day 1 (baseline) and post-intervention on Day ~14 (test).
3. Binge frequency and daily food consumption. This is logged via an online app (MyFitnessPal). Experimenters will extract frequency of subjective binges and objective consumption information (caloric volume of binge foods and non-binge foods consumed). Outcomes from this measure will thus be 1) frequency of subjective binge episodes in the pre-intervention on Day 1 (baseline) period, post-intervention Day ~14 (test) period and at follow-up periods of ~28 days, 3 months, 6 months and 9 months post-intervention 2) average (mean, or median if high skew is present) corresponding macronutrient intake over these same periods.
4. Binge Eating Scale (BES), a questionnaire-based measure of specific binge eating symptomatology severity is used at pre-intervention on Day 1 (baseline), post-intervention Day ~14 (test) and at follow-up periods of ~28 days, 3 months, 6 months and 9months post-intervention.
5. Eating Disorders Examination-Questionnaire (EDE-Q) is used to assess disordered eating at pre-intervention on Day 1 (baseline), post-intervention Day ~14 (test) and at follow-up periods of ~28 days, 3 months, 6 months and 9 months post-intervention.
6. Food Craving Questionnaire State/Trait (FCQ-T/FCQ-S) will be used to assess momentary craving evoked by exposure to binge food images and in-vivo high-palatability food at pre-intervention on Day 1 (baseline), post-intervention Day ~14 (test) and at follow-up periods of ~28 days, 3 months, 6 months and 9 months post-intervention.
7. A subjective, self-rated ‘surprise’ rating is collected to assess the efficacy of the prediction-error generation procedure during memory reactivation. This is a single-item 11-point scale utilised on the second (intervention) day of the study following the binge food memory reactivation or non-binge food memory reactivation procedure.
8. Adherence to task requirements is assessed by measuring performance accuracy during the CBM and sham CBM procedures on the intervention day. Accuracy will be formalised as d’ (d-prime), a normalised measure that takes into account the hit and false alarm rate for binary responses.

1. Height/weight and BMI, resting heart rate, blood pressure, and blood glucose are assessed in-lab at Day 1 (baseline), Day 2 (intervention day) and at Day ~14 post-intervention (test) using high-accuracy scales, an Omron heart rate/blood pressure cuff, and through finger-prick glucose oxidase with an SDCheck monitor, respectively.
2. Basic information, Family History of Eating Disorders and Typical Binge Foods List are recorded pre-intervention on Day 1 (baseline).
3. Depression via the Beck Depression Inventory (BDI), Trait Anxiety via the Spielberger Trait Anxiety Index, Trait Impulsivity via the Barratt Impulsiveness Scale (BIS), Trait Behavioural Inhibition and Activation via the BIS/BAS scale, temporal discounting via the Kirby Delay-Discounting Task (DDT), tolerance for distress via the Distress Tolerance Scale, and disgust via the Disgust Propensity and Sensitivity Scale-Revised, are assessed pre-intervention on Day 1 (baseline) and post-intervention on Day ~14 (test).
4. Food Addiction Symptomatology are assessed using the Yale Food Addiction Scale (Y-FAS), Three Factor Eating Questionnaire-revised (TFEQ-r), and the Power of Food Scale (PFS), at pre-intervention on Day 1 (baseline) period, post-intervention Day ~14 (test) period.
5. Calorie consumption and satiety are assessed via a Timeline Follow-Back (TLFB) and Hunger Scale, respectively, at pre-intervention on Day 1 (baseline) and post-intervention on Day ~14 (test).
6. Anxiety via a Visual Analogue scale, and affect via the Positive and Negative Affect Scale are assessed on Day 2 (intervention), pre and post intervention.
7. The YFAS, BES, FCQT, PFS, TFEQ-r, EDE-Q, and TLFB are used again at follow-up periods of ~28 days, 3 months, 6 months and 9 months post-intervention.
8. Electroencephalography (EEG) in response to binge food images. We will assess neural correlates of successful and unsuccessful response inhibition to binge food images at baseline and test (Day 1 vs. Day ~14). We will also record neural oscillatory activity during the binge memory reactivation/non-reactivation and CBM/sham CBM manipulations on the second study day (intervention day). EEG data is recorded using an EEGo Sports 64 channel amplifier with WaveGuard electrode caps (ANT Neuro).