Brain's Response to Chocolate

Study Overview
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Brief Summary
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The purpose of this study is to test how the brain responds when individuals eat enjoyable foods such as chocolate. Eating certain foods can make one want to keep eating even when feeling full, caused by dopamine in the brain. The researchers believe this dopamine response can be measured by looking at the individual's eye.

Detailed Description
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With obesity at an all-time high, understanding eating behavior beyond physical need is a priority. Food reinforcement is driven by central dopamine activity. However, objective measurement of brain dopamine-related behavioral events is hindered by the lack of non-invasive, accessible techniques that are amenable to testing in a naturalistic environment. The goal of this project is to develop a non-invasive, accessible methodology to measure dopaminergic responses to food in a natural setting. This research will use a novel, hand-held electroretinograph (ERG) that does not require eye dilation and uses a skin electrode to measure retinal dopamine activity. Previous work establishes that retinal dopamine activity can be used as a proxy for central dopamine function. The ability to assess both subjective behavioral variables and central dopaminergic responses simultaneously will provide an ideal approach for innovative studies of the control of eating behavior.

Official Title
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Behavioral Assessment of the Brain Response to Bioactive Food Components Using Electroretinography (Brain's Response to Chocolate)

Conditions
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Overweight, Obesity

Intervention / Treatment
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* Other: Chocolate


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: body mass index 20-30 kg/m2 free of any major illness or disease Exclusion Criteria: food allergies participation in a weight loss diet or exercise program pregnancy lactation metabolic illness or disease (diabetes, renal failure, thyroid illness, hypertension) eye illness or disease (narrow angle glaucoma, macular degeneration, retinal detachment, cataracts) psychiatric, neurological or eating disorders (schizophrenia, depression, Parkinson's Disease, Huntington's Disease, cerebral palsy, stroke, epilepsy, anorexia nervosa or bulimia nervosa) take prescription medications except for oral contraceptives or antihyperlipidemia agents

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 50 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 |
| --- | --- |
| Chocolate<br>Participants will be asked to taste commercially available chocolate varying in sugar, fat and percent cocoa (milk, 70%, 85% and 90% cocoa). | Other: Chocolate<br>* Participants will be asked to taste commercially available chocolate varying in sugar, fat and percent cocoa (milk, 70%, 85% and 90% cocoa).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Retinal dopamine response to oral stimuli | Electroretinograph beta wave amplitude will increase in response to increases in the amount of sugar in the chocolate | 30 minutes | 
| Psychoactive Effects Questionnaire in response to oral stimuli | The number of positive responses on the Psychoactive Effects Questionnaire will increase in response to increases in the sugar content of the chocolate | 30 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Scores on the Binge Eating Scale will correlate with the retinal dopamine and Psychoactive Effect Questionnaire responses | Individual changes in the retinal dopamine response and the number of positive responses on the Psychoactive Effects Questionnaire will correlate with individual scores on the Binge Eating Scale | 30 minutes |