Repeated Food Exposure Via the Olfactory and Gustatory Systems

Approximately two of every three adults in the U.S. are overweight or obese. The high prevalence of overweight/obesity negatively affects the health of the population, as obese individuals are at increased risk for developing several chronic diseases.

Successful control of body weight depends on effectively regulating eating. Satiation, the process by which an eating bout ends, assists with eating regulation, and factors that quicken the onset of satiation may aid with decreasing intake. One factor believed to influence satiation is the rate of decrease in consummatory response (habituation) to repeated presentations of food orosensory cues. Habituation is a basic form of learning, in which behavioral and physiological responses decrease in response to repeated presentations of a stimulus, with the decrease in response unrelated to sensory adaptation/fatigue or motor fatigue.

In one condition, participants will smell lemon and lime across 12 trials (olfactory exposure), in another condition participants will taste the juices across 12 trials (gustatory exposure), and in the last condition participants will smell and taste the juices across 12 trials (olfactory + gustatory exposure). The primary dependent variable will be the amount of salivation in the 12 trials. It is hypothesized that a more rapid decrease in salivation will occur across trials in the combined olfactory and gustatory exposure as compared to the other two conditions, indicating a more rapid rate of habituation

Inclusion criteria

• Dietary restraint scores of less than or equal to 12 on the Three Factor -
• Eating Questionnaire-Cognitive Restraint scale.
• Have a body mass index (BMI) between 18.5 and 24.9.

Exclusion criteria

• Are taking medications or having an illness which might influence salivation, smell, and taste (i.e. upper respiratory illness, methylphenidate, atropine, Benadryl, Elavil, etc)
• Are currently dieting
• Are a binge eater
• Do not at least moderately like lemon or lime flavor scoring < 50 on a 100 mm visual analogue scale
• Are a regular smoker
• Have any dietary restrictions that will inhibit participation including food allergies