Sinding C, Hummel T, Béno N, Prescott J, Bensafi M, Coureaud G, Thomas-Danguin T
Centre des Sciences du Goût et de l'Alimentation, INRAE, CNRS, AgroSup Dijon, Université Bourgogne Franche-Comté, F-21000, Dijon, France.
Smell & Taste Clinic, Department of ORL, University of Dresden Medical School, Dresden, Germany.
Behav Brain Res. 2021 Mar 26;402:113088. doi: 10.1016/j.bbr.2020.113088. Epub 2021 Jan 6.
Blending aromatic mixtures components naturally fuse to form a unique odor - a configuration- qualitatively different from each component's odor. Repeated exposure to the components either in the mixture or separately, favors respectively, configural and elemental processings. The neural bases of such processes are still unknown. We examined the brain correlates of the experienced-induced configural processing of a well-known model of binary blending odor mixture, the aromatic pineapple blending (AB, ethyl maltol + ethyl isobutyrate). Before fMRI recording, half of the participants were repeatedly exposed to the mixture (AB, group Gmix), with the other half exposed to its separate components (A and B; Gcomp). During the fMRI recording, all participants were stimulated with the mixture (AB) and the components (A and B). Finally, participants rated the number of odors perceived for each stimulus. Gmix perceived the AB mixture as less complex than did Gcomp. While Gcomp perceived the mixture as more complex than its components, Gmix did not. These results show the presence of experience-induced configural or elemental processing of the AB mixture in each group. Contrasting the brain activity of Gcomp and Gmix, when stimulated with AB, revealed higher activation in the left orbital part of the inferior frontal gyrus. This result sheds light on this area's function, commonly found activated in olfactory studies, and closely connected with the lateral orbitofrontal cortex. We discuss the role of this area as a mediator of configural percepts between temporal and orbitofrontal areas involved in configural memory processes.
混合香料成分自然融合形成独特气味——一种在性质上与每种成分气味不同的组合。反复接触混合物中的成分或单独接触这些成分，分别有利于构型加工和元素加工。此类加工的神经基础仍不清楚。我们研究了大脑与一种著名的二元混合气味模型——芳香菠萝混合气味（AB，乙基麦芽酚+异丁酸乙酯）的经验诱导构型加工之间的关联。在功能磁共振成像（fMRI）记录之前，一半参与者反复接触混合物（AB，Gmix组），另一半接触其单独成分（A和B；Gcomp组）。在fMRI记录期间，所有参与者都受到混合物（AB）和成分（A和B）的刺激。最后，参与者对每种刺激所感知到的气味数量进行评分。Gmix组认为AB混合物比Gcomp组所认为的更不复杂。虽然Gcomp组认为混合物比其成分更复杂，但Gmix组并非如此。这些结果表明每组中都存在经验诱导的AB混合物构型加工或元素加工。对比Gcomp组和Gmix组在受到AB刺激时的大脑活动，发现额下回左侧眶部有更高的激活。这一结果揭示了该区域的功能，在嗅觉研究中通常发现该区域被激活，并且与外侧眶额皮质紧密相连。我们讨论了该区域作为参与构型记忆过程的颞叶和眶额区域之间构型感知中介的作用。
