Intermittent essential oil diffusion in learning spaces: Exploring olfactory responses and cognitive effects
Narae Choi, Toshio Yamanaka, Akihisa Takemura, Tomohiro Kobayashi, Masato Hirano
Abstract
This study explored the use of intermittent aroma diffusion as a strategy to utilize the psychological benefits of essential oils while minimizing exposure and addressing olfactory adaptation. Given the hypothetical effects of essential oils in reducing stress and enhancing cognitive performance, our research specifically targeted learning spaces. Initially, we examined olfactory responses to intermittent aroma diffusion of sweet orange essential oil at intervals of 5 and 10 min, compared to continuous exposure. Key parameters such as odor intensity, preference, and acceptability were evaluated in these intermittent aroma environments. Subsequently, we investigated the impact of this intermittent diffusion on students' mood and attention. Based on the perceived odor intensity, olfactory responses were classified into three types: sensitive, invariable, and variable. The findings revealed that diffusion at a 10-min interval led to a more acute perception of odor changes and higher levels of preference and acceptability than the 5-min interval, suggesting an effective balance between enhancing odor perception and mitigating olfactory adaptation. However, this condition did not significantly influence students’ mood and performance during attention and concentration tasks. Future research should examine a broader range of essential oils and diffusion intervals to fully realize the benefits of intermittent aroma environments.