Kupers Ron, Dousteyssier Océane, Delforge Jérôme, Gonnot Vanessa, Kantono Kevin, Blerot Bernard, Pêtre Arnaud, Dricot Laurence, Heinecke Armin
Institute of Neuroscience (IoNS), UCLouvain, Brussels, Belgium.
Department of Neuroscience, Panum Institute, University of Copenhagen, Copenhagen, Denmark.
Front Neurosci. 2025 Jun 10;19:1555922. doi: 10.3389/fnins.2025.1555922. eCollection 2025.
Most brain imaging studies on olfaction focus on short-term odorant stimuli, with few examining long-lasting odor exposure or its after-effects. In this study, we utilized resting-state fMRI (rsfMRI) to investigate the effects of prolonged odor exposure to lavender on brain activity and whether these persist post-exposure.
Fourteen healthy women underwent two fMRI sessions, conducted one week apart, in a randomized order. Both sessions included rsfMRI scans before, during, and up to 2 h after a 14 min exposure to either lavender essential oil or a non-odorant control.
An Independent Component Analysis identified the salience network (SAL) and default mode network (DMN) as the most consistent resting-state networks. A two-factorial ANOVA revealed significant time-varying interaction effects between the SAL and DMN. During odor exposure, functional connectivity (FC) increased within the SAL, and a negative correlation between the SAL and DMN appeared, which intensified immediately after exposure. Two hours post-exposure, the FC between SAL and DMN turned positive.
These findings suggest that prolonged odorant exposure to lavender can induce long-lasting brain effects detectable up to 2 h afterwards in women. This proof-of-concept study should be extended to other odorants and to men, and offers new possibilities for exploring the effects of aromatherapy or other odor exposure interventions on brain activity.
大多数关于嗅觉的脑成像研究聚焦于短期气味刺激，很少有研究考察长期气味暴露或其后续影响。在本研究中，我们利用静息态功能磁共振成像（rsfMRI）来探究长时间暴露于薰衣草气味对大脑活动的影响，以及这些影响在暴露后是否持续存在。
14名健康女性以随机顺序接受两次功能磁共振成像检查，两次检查间隔一周。两次检查均包括在暴露于薰衣草精油或无气味对照物14分钟之前、期间以及之后长达2小时的rsfMRI扫描。
独立成分分析确定突显网络（SAL）和默认模式网络（DMN）为最一致的静息态网络。双因素方差分析显示SAL和DMN之间存在显著的随时间变化的交互作用。在气味暴露期间，SAL内的功能连接（FC）增加，SAL和DMN之间出现负相关，且在暴露后立即增强。暴露后两小时，SAL和DMN之间的FC变为正相关。
这些发现表明，长时间暴露于薰衣草气味可在女性中诱发长达2小时后仍可检测到的持久脑效应。这项概念验证研究应扩展到其他气味以及男性，并为探索芳香疗法或其他气味暴露干预对大脑活动的影响提供了新的可能性。
