High-precision mapping reveals the structure of odor coding in the human brain.
High-precision mapping reveals the structure of odor coding in the human brain.
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高精度绘图揭示了人脑中气味编码的结构。
DOI：
10.1038/s41593-023-01414-4
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发表时间：
2023
影响因子：
25
通讯作者：
Kahnt,Thorsten
中科院分区：
文献类型：
--
作者：
Sagar,Vivek;Shanahan,LauraK;Zelano,ChristinaM;Gottfried,JayA;Kahnt,Thorsten
气味感知本质上是主观的。先前的研究表明，气味分子在嗅觉皮层中唤起了分布的活动模式，但这些模式如何映射到主观气味感知尚不清楚。在本研究中，我们收集了3名受试者对160种气味的神经成像反应（每个受试者18小时），以探索特异气味感知的神经编码机制。我们发现，眼窝前额皮质（OFC）的活动代表了对气味的细粒度感知身份，而这种差异在梨状皮质（PirC）和杏仁核中不那么明显。此外，感知编码模型的实现使我们能够预测嗅觉功能磁共振成像对新气味的反应，揭示编码感知空间的维度从PirC到OFC增加。低阶维的编码具有普遍性，而高阶维的编码具有特殊性。这些结果为气味编码的皮层机制提供了新的见解，并表明主观嗅觉感知存在于OFC。
Odor perception is inherently subjective. Previous work has shown that odorous molecules evoke distributed activity patterns in olfactory cortices, but how these patterns map on to subjective odor percepts remains unclear. In the present study, we collected neuroimaging responses to 160 odors from 3 individual subjects (18 h per subject) to probe the neural coding scheme underlying idiosyncratic odor perception. We found that activity in the orbitofrontal cortex (OFC) represents the fine-grained perceptual identity of odors over and above coarsely defined percepts, whereas this difference is less pronounced in the piriform cortex (PirC) and amygdala. Furthermore, the implementation of perceptual encoding models enabled us to predict olfactory functional magnetic resonance imaging responses to new odors, revealing that the dimensionality of the encoded perceptual spaces increases from the PirC to the OFC. Whereas encoding of lower-order dimensions generalizes across subjects, encoding of higher-order dimensions is idiosyncratic. These results provide new insights into cortical mechanisms of odor coding and suggest that subjective olfactory percepts reside in the OFC.