Research suggests that transient emotional episodes produces sustained effects on psychological functions and brain activity during subsequent resting state. In this fMRI study we investigated whether transient emotions induced by smells could impact brain connectivity at rest in a valence-specific manner. The results suggest a sustained reconfiguration of parts of the default mode network which become more connected with areas implicated in olfactory processing, emotional learning, and action control. We found lingering effects of odorants on subsequent resting state that predominantly involved connections of the precuneus with a network comprising the insula, amygdala, medial orbital gyrus. Unpleasant smells in particular predicted greater coupling between insula, hippocampal structures, and prefrontal cortex, possible reflecting enhanced aversive learning and avoidance motivation. More broadly, our study illustrates a novel approach to characterize the impact of smells on brain function and differentiate the neural signatures of their valence, during task-free rest conditions.

研究表明，短暂的情绪发作在随后的静息状态下会对心理功能和大脑活动产生持续影响。在这项功能磁共振成像研究中，我们调查了由气味引起的短暂情绪是否可以以价态特定的方式影响静止时的大脑连通性。结果表明，默认模式网络的各个部分将持续重新配置，这些部分与嗅觉处理，情绪学习和动作控制相关的区域之间的联系更加紧密。我们发现加味剂对随后的静止状态的挥之不去的影响主要涉及前胎与包括岛突，杏仁核，眶内侧回的网络的连接。特别是难闻的气味预示着岛上，海马结构和前额叶皮层之间的耦合性增强，可能反映出反感学习和回避动机的增强。更广泛地说，我们的研究表明了一种在无任务休息条件下表征气味对脑功能的影响并区分其价的神经信号的新颖方法。