Neurofeedback During Eating for Bulimia Nervosa

Study Overview
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Brief Summary
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The purpose of this study is to examine the effects of noninvasive prefrontal cortex (PFC) neurofeedback during eating in women with bulimia nervosa (BN) using a wearable brain imaging device, functional near-infrared spectroscopy (fNIRS). The investigators will examine how this training may influence inhibitory control and BN symptoms.

Detailed Description
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The purpose of this study is to examine the effects of PFC neurofeedback during eating in women with bulimia nervosa (BN) using fNIRS. Specifically, the study aims 1) to demonstrate ventrolateral PFC (vlPFC) neurofeedback target engagement in women with BN using fNIRS; and 2) to link changes in PFC activation to changes in inhibitory control and eating-related symptoms. Data will be collected from women with BN who will be randomly assigned to one of two group conditions (real or sham-control neurofeedback during eating). Participation includes a phone screening assessment, psychodiagnostic assessment, one in-person evaluation, one neurofeedback session, behavioral tasks, online questionnaires before and after the neurofeedback session, and a remote follow-up assessment.

Official Title
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Neurofeedback During Eating: A Novel Mechanistic Treatment for Bulimia Nervosa

Conditions
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Bulimia Nervosa

Intervention / Treatment
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* Other: Real fNIRS Neurofeedback
* Other: Sham-Control fNIRS Neurofeedback


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: Female Aged 18 to 35 years Meet diagnostic criteria for bulimia nervosa Currently between 85 and 130% of the expected weight for height English-speaking Exclusion criteria: Ongoing medical treatment, major medical condition, or psychiatric disorder that may interfere with study variables or participation Current psychotherapy focused primarily on eating disorder symptoms Pregnancy or planned pregnancy, or lactation during the study period Allergy to ingredients in the standardized meal or in the shake

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 35 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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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Participants will be assigned to one of two conditions, either the experimental or sham neurofeedback arm.
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Real fNIRS Neurofeedback Arm<br>Participants assigned to the experimental arm will see their true, real-time brain activation (i.e., active real-time neurofeedback) during the neurofeedback session. This activation will be displayed to the participant as a thermometer that will increase as brain activation in the target region increases. | Other: Real fNIRS Neurofeedback<br>* Participants will be instructed to use real-time fNIRS neurofeedback to non-invasively regulate neural activation associated with symptoms in individuals with bulimia nervosa. During the training, participants will view images on a computer screen, listen to sounds, and consume a shake.<br>|
| Sham Comparator: Sham-Control fNIRS Neurofeedback Arm<br>Participants assigned to the sham-control arm will see false feedback (or a fake signal) that is not connected to their right vlPFC activation during the neurofeedback session. | Other: Sham-Control fNIRS Neurofeedback<br>* Participants will be instructed to use sham real-time fNIRS neurofeedback to non-invasively regulate neural activation associated with symptoms in individuals with bulimia nervosa. During the training, participants will view images on a computer screen, listen to sounds, and consume a shake.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Functional near-infrared spectroscopy (fNIRS)-measured neural activation and connectivity | The investigators will evaluate changes in PFC neural activation and connectivity as a function of neurofeedback. | approximately 1 hour | 
| Go/no-go task performance | Participants will complete a go/no-go task 1 week before and 1 week after the neurofeedback session to measure inhibitory control. Participants behavioral performance on the go/no-go task will be determined by the percentage of incorrect responses made as they are prompted to react to different pictorial stimuli. Participants' percentages of error can range from 0% to 100%. A higher percentage indicates a lower behavioral performance on the task. | 2 weeks | 
| Number of loss-of-control eating and purging episodes | Frequency of loss-of-control eating and purging episodes. Participants will self-report on how often loss-of-control eating and purging episodes occur using electronic daily diaries in the week before and the week after the neurofeedback session. | 2 weeks | 
| Severity of loss-of-control eating scale | Severity of loss-of-control eating. Participants will rate the severity of their feelings of control over eating and purging episodes on a Likert-type scale from 0-10. Higher score indicates greater severity of loss of control. | 2 weeks |