Department of Biology, Georgetown University, Washington, DC, United States.
Department of Biological Sciences and Neuroscience & Mental Health Institute, University of Alberta, Edmonton, Canada.
Elife. 2022 Sep 21;11:e79107. doi: 10.7554/eLife.79107.
Learning and memory storage is a complex process that has proven challenging to tackle. It is likely that, in nature, the instructive value of reinforcing experiences is acquired rather than innate. The association between seemingly neutral stimuli increases the gamut of possibilities to create meaningful associations and the predictive power of moment-by-moment experiences. Here, we report physiological and behavioral evidence of olfactory unimodal sensory preconditioning in fruit flies. We show that the presentation of a pair of odors (S1 and S2) before one of them (S1) is associated with electric shocks elicits a conditional response not only to the trained odor (S1) but to the odor previously paired with it (S2). This occurs even if the S2 odor was never presented in contiguity with the aversive stimulus. In addition, we show that inhibition of the small G protein , a known forgetting regulator, facilitates the association between S1/S2 odors. These results indicate that flies can infer value to olfactory stimuli based on the previous associative structure between odors, and that inhibition of lengthens the time window of the olfactory 'sensory buffer', allowing the establishment of associations between odors presented in sequence.
学习和记忆存储是一个复杂的过程，证明具有挑战性。在自然界中，强化经验的指导价值可能是后天获得的，而不是先天的。看似中性的刺激之间的关联增加了创建有意义的关联的可能性范围，并提高了即时经验的预测能力。在这里，我们报告了果蝇中嗅觉单模态感觉前条件作用的生理和行为证据。我们表明，在其中一种气味（S1 和 S2）之前呈现一对气味（S1 和 S2）会引起条件反应，不仅对训练气味（S1），而且对先前与它配对的气味（S2）产生条件反应。即使 S2 气味从未与厌恶刺激同时出现也是如此。此外，我们还表明，抑制小 G 蛋白，一种已知的遗忘调节剂，可促进 S1/S2 气味之间的关联。这些结果表明，苍蝇可以根据气味之间先前的联想结构推断出嗅觉刺激的价值，并且抑制作用会延长嗅觉“感觉缓冲区”的时间窗口，从而允许在连续呈现的气味之间建立关联。
