Effects of Inhibitory Control Training in Eating Behaviors

Study Overview
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Brief Summary
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Overweight and obese individuals will be randomly assigned to a food-specific or generic inhibitory control training. Food intake, weight, and neural indices of inhibitory control will be assessed prior, immediately after the 4-week intervention, and 12-weeks after intervention completion to assess the effectiveness of a mobile inhibitory control training intervention over time for health outcomes.

Detailed Description
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All participants will report to the lab for a baseline session, where their weight, average food intake for three days (using the Automated Self-Administer 24-hour Dietary Recall [ASA24] system), neural indices of inhibitory control (as assessed by the N2 event-related potential component during a food and genetic go/no-go task), appetitive drive toward food (as measured by the Power of Food Scale) and basic demographic information will be assessed. Based off their gender and baseline levels of inhibitory control (indicated by the N2), participants will be assigned to a four week food-specific inhibitory control training or a generic inhibitory control training. Trainings are administered on a mobile device via an app and participants select four our of five business days to complete the trainings on. Immediately after the four weeks, participants will come in for a follow-up session where their weight, food intake, N2, and appetitive drive to food will be assessed again. Finally, participants will have a 12-week waiting period where they do not complete the trainings. After the 12 weeks, they will come in for a final lab visit where their weight, food intake, N2, and appetitive drive to food will be assessed one last time.

Official Title
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The Effects of Food-Specific Inhibitory Control Training on Weight, Diet, and Neural Indices in Overweight and Obese Adults

Conditions
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Overweight and Obesity

Intervention / Treatment
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* Behavioral: Inhibitory Control Training


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Overweight or Obese (BMI > 25 kg/m2) Exclusion Criteria: Diagnosis of a psychological disorder (e.g., major depressive disorder, general anxiety disorder), neurological disorder (e.g., epilepsy, stroke), learning disability, or eating disorder (e.g., anorexia nervosa, bulimia nervosa, binge eating disorder) Metabolic/chronic disease (e.g., cardiovascular disease, Type II diabetes) Pregnant or lactating Current participation in a weight loss diet Food allergies Head injury that resulted in a loss of consciousness Avid exercisers (i.e., participate in at least 20 minutes of vigorous physical activity more than three times a week)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: There are two arms of this study: food-specific inhibitory control training (condition of interest) and a generic inhibitory control training (active control). Given baseline levels of inhibitory control (assessed at baseline visit), participants are randomly assigned to the generic or food-specific month long inhibitory control training. All other protocols, including baseline and follow-up visits and assessment of food intake and weight, are identical and follow the same time line across the two arms.
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Inhibitory Control Training to Food Items<br>Participants complete a 10 minute training task once a day, 4 days a week, for 4 weeks. Task is administered using a mobile app (Paradigm mobile) that is installed on an iPhone or iPad. Participants receive an instruction text/email at 9am on their chosen weekdays with instructions on what task to complete and a reminder text/email at 5pm if the task has not yet been completed. Research team receives an email when the task has been completed. When the task is administered, participants see a picture for 1250ms with an inter-stimulus interval of 1250ms and have to indicate which side of the screen the picture appears (go trials). Participants are instructed to not make a response when the picture is surrounded by a black box (no-go trials). There are 6 blocks with 36 trials each, half being go and half being no-go trials. High-calorie foods are always no-go trials and low-calorie foods are always go trials. | Behavioral: Inhibitory Control Training<br>* Computerized go/no-go task where individuals make responses to certain items (go trials) and withhold responses from certain items (no-go trials, in this case, trials surrounded by a black box). Intervention is designed to target and improve inhibitory control cognitive mechanisms in general (generic arm) or towards high-calorie foods specifically (food arm).<br>|
| Active Comparator: Inhibitory Control Training to Neutral Items<br>Participants complete a 10 minute training task once a day, 4 days a week, for 4 weeks. Task is administered using a mobile app (Paradigm mobile) that is installed on an iPhone or iPad. Participants receive an instruction text/email at 9am on their chosen weekdays with instructions on what task to complete and a reminder text/email at 5pm if the task has not yet been completed. Research team receives an email when the task has been completed. When the task is administered, participants see a picture for 1250ms with an inter-stimulus interval of 1250ms and have to indicate which side of the screen the picture appears (go trials). Participants are instructed to not make a response when the picture is surrounded by a black box (no-go trials). There are 6 blocks with 36 trials each, half being go and half being no-go trials. All pictures are of household items. | Behavioral: Inhibitory Control Training<br>* Computerized go/no-go task where individuals make responses to certain items (go trials) and withhold responses from certain items (no-go trials, in this case, trials surrounded by a black box). Intervention is designed to target and improve inhibitory control cognitive mechanisms in general (generic arm) or towards high-calorie foods specifically (food arm).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Caloric Intake | Using the Automated Self-Administered 24-hour Dietary Recall (ASA24), participants will record their food intake for two weekdays and one weekend, two of which will be randomly assigned and one which will be the day they report to their lab visit. Caloric intake, as quantified by ASA24, will be averaged for the three days and statistically analyzed to see if average caloric intake changes over time due to the inhibitory control training arm. | Three days will be completed at baseline, immediately after the intervention, and at the 12 week follow-up visit (total of 9 recalls) | 
| Weight | Weight will be measured in kilograms using a stadiometer to see if weight changes over the course of the study. | Assessed at baseline, immediately after the intervention, and at the 12-week follow-up visit. | 
| N2 Event-Related Potential Component | The N2 is a negative deflection in the event-related potential waveform occurring 200 to 300 ms after the onset of a stimulus and is larger (i.e., more negative) when an individual has to withhold a dominant response. It is a neural reflection of inhibitory control. The investigators will assess if the N2 amplitude gets larger as a result of inhibitory control training (as individuals will be better at recruiting inhibitory control resources). The investigators will also see if the N2 predicts who is successful at losing weight and reducing caloric intake after the intervention, to better understand the mechanism of action for inhibitory control training. | Assessed at baseline, immediately after the intervention, and at the 12-week follow-up visit. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| No-Go Accuracy | Percent of correct no-go trials during the laboratory go/no-go tasks. The investigators are interested if this improves due to the intervention. | Assessed at baseline, immediately after the intervention, and at the 12-week follow-up visit. | 
| Correct Go Reaction Times | Time in ms to correctly respond to a go trial during the laboratory tasks. The investigators are interested if reaction times get faster due to the intervention. | Assessed at baseline, immediately after the intervention, and at the 12-week follow-up visit. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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inhibitory control training, food, event-related potentials, weight reduction