Repeated Food Exposure Via the Olfactory and Gustatory Systems

Increasing exposure to a single orosensory cue without ingestion of additional energy may promote an increased rate of habituation, more rapid satiation, and reduced intake. This exposure can occur via smell (olfactory) and taste (gustatory) systems.It is not clear if repeated exposure via the combined olfactory and gustatory systems increases the rate of habituation more so than repeated exposure through one of these systems. Thus, the purpose of this investigation is to examine the amount of salivation occurring in 12 trials of exposure to a food via the olfactory, gustatory, and combined olfactory and gustatory systems. 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.

Study Overview

• Status: Completed
• Conditions: Habituation
• Intervention / Treatment: Other: Habituation

Detailed Description

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

• Study Type: Interventional
• Enrollment (Actual): 27
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Tennessee
    • Knoxville, Tennessee, United States, 37996
      • Healthy Eating and Activity Lab, University of Tennessee

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 30 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

Description

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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Single Group Assignment
• Masking: Single

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Olfactory; Habituation of olfactory response	Other: Habituation; Habituation will be measured for each the conditions (olfactory, gustatory, olfactory and gustatory) of the study.
Experimental: gustatory; Habituation of gustatory response.	Other: Habituation; Habituation will be measured for each the conditions (olfactory, gustatory, olfactory and gustatory) of the study.
Experimental: olfactory and gustatory; Habituation of olfactory and gustatory response	Other: Habituation; Habituation will be measured for each the conditions (olfactory, gustatory, olfactory and gustatory) of the study.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Amount of Salivation	12 trials (90 minutes)

Collaborators and Investigators

• Sponsor: The University of Tennessee, Knoxville
• Investigators: Principal Investigator: Hollie A Raynor, PhD RD LDN, University of Tennessee

Study record dates

Study Major Dates

• Study Start: July 1, 2012
• Primary Completion (Actual): December 1, 2015
• Study Completion (Actual): December 1, 2015

Study Registration Dates

• First Submitted: July 24, 2012
• First Submitted That Met QC Criteria: July 25, 2012
• First Posted (Estimate): July 26, 2012

Study Record Updates

• Last Update Posted (Actual): April 5, 2018
• Last Update Submitted That Met QC Criteria: April 3, 2018
• Last Verified: April 1, 2018

More Information

Terms related to this study

• Keywords: gustatory response; olfactory response
• Other Study ID Numbers: 8879B