Dedicated odor-taste stimulation design for fMRI flavor studies

Area of Science:

• Neuroscience
• Sensory Science
• Biophysics

Background:

• Flavor perception involves integrating taste and odor signals in the brain.
• Brain imaging techniques like fMRI are valuable for studying flavor processing.
• Delivering stimuli, especially liquids, during fMRI in a supine position presents challenges for odorant release timing.

Purpose of the Study:

• To investigate in vivo odorant release via the retronasal pathway during supine stimulation.
• To assess methods for improving odorant release, such as delayed swallowing and velum open training (VOT).
• To determine the optimal timing of odorant release for brain imaging of flavor perception.

Main Methods:

• Utilized proton transfer reaction mass spectrometry (PTR-MS) to measure in vivo odorant release.
• Administered retronasal odor-taste stimulation in a supine position.
• Evaluated the impact of avoiding/delaying swallowing and VOT on odorant release.

Main Results:

• Odorant release was detected during retronasal stimulation in a supine position, prior to swallowing.
• Velum open training (VOT) did not enhance odorant release.
• Odorant release timing during stimulation was more suitable for fMRI BOLD signal acquisition than post-swallowing release.

Conclusions:

• The developed method enables optimal in vivo odorant release during the stimulation phase for brain imaging.
• This approach facilitates high-quality fMRI studies of flavor processing by minimizing swallowing-related motion artifacts.
• Findings contribute to a better understanding of the neural mechanisms underlying flavor perception.