Neuronal and Behavioral Effects of Implicit Priming in Obese Individuals
Study Overview
Status
Conditions
Intervention / Treatment
Detailed Description
One factor that may contribute to susceptibility to obesity is a high responsivity to high-calorie foods in terms of cognitive factors such as emotional associations, reward value or reinforcing properties of food. Many of these processes involve learned associations thought to develop via classical conditioning through repeated pairings with external stimuli, which can influence food preferences and intake. As such, improving our understanding of the neuronal mechanisms underlying these processes and attempting to modify them may be a useful strategy to promote weight loss and maintenance. Therefore, the proposed study aims to investigate the effects of altering food perception on neuronal responses and food intake behaviors by using implicit priming, in which positively or negatively valenced images are presented immediately prior to food images, but are not consciously perceived.
The project goals are to determine the impact of the implicit priming intervention on both brain responses to food cues and on food intake behaviors in overweight/obese individuals. Food image ratings were assessed before and after either (a) an active implicit priming intervention or (b) a control intervention. One group of participants (n = 47; "MRI sample") completed the intervention during an fMRI scan and completed a visual food cues task both before and after the intervention (during fMRI), to assess intervention-related change in neuronal responses to food cues. In this group, food intake measures were also taken following fMRI. In a separate group of participants (n = 45; "Behavioral-only sample"), the primary outcome measure was the change in food image ratings from pre- to post-intervention; fMRI and measures of food intake were not assessed in this group.
Study Type
Enrollment (Actual)
Phase
- Not Applicable
Contacts and Locations
Study Locations
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Colorado
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Aurora, Colorado, United States, 80045
- University of Colorado Anschutz Medical Campus
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-
Participation Criteria
Eligibility Criteria
Ages Eligible for Study
Accepts Healthy Volunteers
Genders Eligible for Study
Description
Inclusion Criteria:
- Overweight/obese adults
- Healthy weight adults
Exclusion Criteria:
- Vegetarian, vegan, or having other wide-ranging food restrictions
- Currently dieting
- MRI exclusion criteria, if in MRI sample (e.g., claustrophobia, metal in the body)
Study Plan
How is the study designed?
Design Details
- Primary Purpose: Treatment
- Allocation: Randomized
- Interventional Model: Parallel Assignment
- Masking: Triple
Arms and Interventions
Participant Group / Arm |
Intervention / Treatment |
|---|---|
|
Experimental: Active Implicit Priming (MRI sample)
Participants will complete active implicit priming, in which food images are implicitly primed (i.e., below conscious awareness) with images of positive or negative affect.
In addition to measures of food image ratings, this group completed a visual food cues scan during fMRI to assess change in neuronal response to food cues.
They also completed a measure of food intake post-intervention.
|
A 10-minute implicit priming intervention, associating food images with images of positive or negative valence.
|
|
Placebo Comparator: Control Implicit Priming (MRI sample)
Participants will complete a control implicit priming intervention, which matches the active intervention, but with neutral stimuli as primes.
In addition to measures of food image ratings, this group completed a visual food cues scan during fMRI to assess change in neuronal response to food cues.
They also completed a measure of food intake post-intervention.
|
A 10-minute implicit priming intervention, associating food images with images of neutral valence.
|
|
Experimental: Active Implicit Priming (Behavioral-only sample)
Participants will complete active implicit priming, in which food images are implicitly primed (i.e., below conscious awareness) with images of positive or negative affect.
|
A 10-minute implicit priming intervention, associating food images with images of positive or negative valence.
|
|
Placebo Comparator: Control Implicit Priming (Behavioral-only sample)
Participants will complete a control implicit priming intervention, which matches the active intervention, but with neutral stimuli as primes.
|
A 10-minute implicit priming intervention, associating food images with images of neutral valence.
|
What is the study measuring?
Primary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
|---|---|---|
|
Change in Food Image Ratings
Time Frame: Baseline to within 10 minutes post-intervention
|
Food image ratings (high-calorie foods) change from baseline, measured within 10 minutes post-intervention.
Food images are rated on "desire to eat" by visual analogue scale (0-100; higher scores mean greater desire to eat).
Negative values indicate reduced scores post-intervention compared to baseline, with greater numbers indicating greater reduction.
|
Baseline to within 10 minutes post-intervention
|
|
Neuronal Response to Food Cues
Time Frame: Baseline to post-intervention
|
Neuronal response while viewing visual food cues will be measured using functional magnetic resonance imaging (fMRI).
Primary outcome was insula response change from baseline, as measured within 20 minutes after the intervention.
A bilateral region of interest (ROI) for the insula was defined anatomically, with mean difference from baseline to post-intervention (% BOLD signal change) calculated across all voxels for that ROI.
A positive number indicates a reduced response (with higher numbers indicating greater change) and a negative number indicates an increased response.
|
Baseline to post-intervention
|
Secondary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
|---|---|---|
|
Food Intake
Time Frame: 1 hour post-intervention
|
Food intake during ad-lib lunch (kcals)
|
1 hour post-intervention
|
Collaborators and Investigators
Sponsor
Investigators
- Principal Investigator: Jason R Tregellas, PhD, University of Colorado - Anschutz Medical Campus
- Principal Investigator: Kristina T Legget, PhD, University of Colorado - Anschutz Medical Campus
Publications and helpful links
General Publications
- Legget KT, Cornier MA, Erpelding C, Lawful BP, Bear JJ, Kronberg E, Tregellas JR. An implicit priming intervention alters brain and behavioral responses to high-calorie foods: a randomized controlled study. Am J Clin Nutr. 2022 Apr 1;115(4):1194-1204. doi: 10.1093/ajcn/nqac009.
- Legget KT, Cornier MA, Rojas DC, Lawful B, Tregellas JR. Harnessing the power of disgust: a randomized trial to reduce high-calorie food appeal through implicit priming. Am J Clin Nutr. 2015 Aug;102(2):249-55. doi: 10.3945/ajcn.115.106955. Epub 2015 Jun 24.
Study record dates
Study Major Dates
Study Start (Actual)
Primary Completion (Actual)
Study Completion (Actual)
Study Registration Dates
First Submitted
First Submitted That Met QC Criteria
First Posted (Estimate)
Study Record Updates
Last Update Posted (Actual)
Last Update Submitted That Met QC Criteria
Last Verified
More Information
Terms related to this study
Additional Relevant MeSH Terms
Other Study ID Numbers
- 13-1786
- R21DK102052 (U.S. NIH Grant/Contract)
- P30DK048520 (U.S. NIH Grant/Contract)
Plan for Individual participant data (IPD)
Plan to Share Individual Participant Data (IPD)?
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