Does Sweet Taste Potentiate Nicotine Cue Reactivity?
Condition: Healthy
Study type: Interventional
Phase: Phase 1

Summary: 
      The investigators' aim is to test the prediction that sweet taste perception enhances the
      ability of nicotine to induce neural plastic changes in brain reward circuits to increase the
      saliency, liking and brain reactivity to the sight and vaporized flavor of electronic
      cigarettes (e-cigarettes).
    

Detailed description: 
      Alternative tobacco products are becoming increasingly available in the US market and are
      promoted as potentially less deleterious compared to cigarettes. These products are
      increasing in usage as either a substitution for cigarette smoking or in addition to smoking.
      One particular appeal is that they often combine nicotine with sweet taste and flavors, which
      are themselves reinforcing. The primary goal of this project is to determine if sweet taste
      can potentiate the reinforcing properties of nicotine. Similar to nicotine, cues predicting
      the availability of carbohydrates can stimulate intake, even in the absence of hunger. The
      investigators have developed a novel flavor-nutrient conditioning paradigm to study the
      reinforcing properties of carbohydrates. Novel flavors are paired with 0 or 113 kcal
      carbohydrate and increases in flavor-cue reactivity (change in liking and brain response)
      when later sampled in the absence of the carbohydrate provide a measure of the reinforcing
      potency. For smokers, the aroma of tobacco is a potent cue that can promote smoking behavior.
      Using a modified version of our conditioning paradigm, our specific aim is to test the
      prediction that sweet taste perception enhances the ability of nicotine to induce neural
      plastic changes in brain reward circuits to increase the saliency, liking and brain
      reactivity to the sight and vaporized flavor of electronic cigarettes (e-cigarettes).
      Participants will smoke e-cigarettes that contain nicotine and an unsweetened vaporized
      flavor, nicotine and a sweet vaporized flavor or only a sweet vaporized flavor (no nicotine).
      The investigators predict that response in the nucleus accumbens and hypothalamus to the
      sight and vaporized flavor of the e-cigarette that was paired with nicotine and sweet taste
      will be greater than the responses to the sight and vaporized flavors associated with the
      other e-cigarettes. The investigators further predict that liking and wanting will increase
      more for the sight and vaporized flavor associated with both nicotine and sweet taste. This
      finding would provide strong evidence that sweet taste potentiates the reinforcement potency
      of nicotine and could therefore promote use.
    

Intervention name(s): flavor and sweetener; flavor and nicotine; flavor, nicotine and sweetener; flavor
Intervention type(s): Device; Device; Device; Device
Intervention description(s): maltol added as sweetener to e-cigarette with flavor; 12 mg of nicotine added to e-cigarette with flavor; 12 mg nicotine and maltol (sweetener) added to e-cigarette with flavor; flavored e-cigarette stand alone without added nicotine and maltol (sweetener)
Intervention MeSH terms: Nicotine
Allocation: Non-Randomized
Intervention model: Factorial Assignment
Masking: Double (Participant, Investigator)
Primary purpose: Basic Science
Keywords: Perception; brain response; nicotine; taste