Influence of Repeated Odor Adaptation Experience on the Olfactory Response

Abstract

Recent studies have reported that essential oils and fragrances sprayed indoors affect psychologica evaluation and intellectual productivity. However, the effects of long-term exposure to fragrances on the human body have not been well studied, and there are still many unresolved issues. Therefore, in this study, the effects of repeated exposure to fragrances on changes in the perception of fragrances as a study for long-term operation of fragrance environments were investigated. In order to investigate the effect of fragrance repetition on threshold and odor perception, a panel experiment with 19 subjects was conducted using rosemary essential oil and scatole. The Rosemary was be exposed and the Scatole was not. The conditions were repetition frequency of adaptation. Regarding thresholds, several panels showed an increase in thresholds for rosemary with exposure and a decrease in thresholds for scatole, indicating a long-term acclimation trend due to repeated exposure to fragrances. As for the subjective evaluation of fragrance, the evaluation of fragrance preference and pleasantness/ unpleasantness tended to change to the neutral side in the case of lower frequency and longer duration. In the future, experiments that tend to increase the number of conditions of the frequencies and duration of repeated exposure will be conducted.