2020 年 27 巻 1 号 p. 109-119
The orthonasal and retronasal aromas are thought to affect odor-taste interactions differently. Many possible candidates can be postulated as cues for the identification of these aromas, and one of them is the kinetic sensation of breathing. However, in the previous study that investigated the relationship between breath and odor-taste interaction, the spout for presenting the odor stimulus was placed in the oral cavity during exhalation and the front of the nose during inhalation. This difference in placement results in significant differences in odor intensity between conditions. In addition, a tube in the oral cavity prevents food consumption and only allows participants to undergo experiments on the effects of odor while drinking. To investigate breath and odor-taste interaction, there is a need for a methodology that allows participants to stably smell when they are both breathing in and breathing out is needed. We placed the tube for presenting the odor stimulus in the nasal cavity and blocked the gap between the tube and the nostril. Participants consistently experienced smell stimuli during both inhalation and exhalation. We found that if the gap between the tube and the nostril are completely blocked, a insertion of less than 1cm of tubing is sufficient. Our novel methodology enabled the presentation of the smell perceived during exhalation and inhalation through a single nostril tube. More studies would be required to clarify whether the odor presented during exhalation in the present study was similar to the retronasal odor evaluated in previous studies.
