The cortex organizes sensory information to enable discrimination and generalization 1 – 4 . As systematic representations of chemical odour space have not yet been described in the olfactory cortex, it remains unclear how odour relationships are encoded to place chemically distinct but similar odours, such as lemon and orange, into perceptual categories, such as citrus 5 – 7 . Here, by combining chemoinformatics and multiphoton imaging in the mouse, we show that both the piriform cortex and its sensory inputs from the olfactory bulb represent chemical odour relationships through correlated patterns of activity. However, cortical odour codes differ from those in the bulb: cortex more strongly clusters together representations for related odours, selectively rewrites pairwise odour relationships, and better matches odour perception. The bulb-to-cortex transformation depends on the associative network originating within the piriform cortex, and can be reshaped by passive odour experience. Thus, cortex actively builds a structured representation of chemical odour space that highlights odour relationships; this representation is similar across individuals but remains plastic, suggesting a means through which the olfactory system can assign related odour cues to common and yet personalized percepts. Both piriform cortex and its sensory inputs from the olfactory bulb represent chemical odour relationships, but cortex reshapes relational information inherited from the sensory periphery to enhance odour generalization and to reflect experience.

中文翻译：

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气味空间皮层表征的结构和灵活性

皮层组织感觉信息以实现辨别和概括 1 – 4 。由于尚未在嗅觉皮层中描述化学气味空间的系统表征，因此尚不清楚气味关系如何编码以将化学上不同但相似的气味（例如柠檬和橙子）归入感知类别，例如柑橘 5 – 7。在这里，通过结合小鼠的化学信息学和多光子成像，我们表明梨状皮质及其来自嗅球的感觉输入通过相关的活动模式代表化学气味关系。然而，皮质气味编码与球茎中的不同：皮质更强烈地将相关气味的表征聚集在一起，选择性地重写成对气味关系，并更好地匹配气味感知。灯泡到皮层的转变取决于起源于梨状皮层的联想网络，并且可以通过被动的气味体验进行重塑。因此，皮层积极构建化学气味空间的结构化表征，突出气味关系；这种表现形式在个体之间是相似的，但仍然具有可塑性，这表明嗅觉系统可以通过这种方式将相关的气味线索分配给常见但个性化的感知。梨状皮质及其来自嗅球的感觉输入都代表化学气味关系，但皮质重塑从感觉外围继承的关系信息，以增强气味泛化和反映经验。因此，皮层积极构建化学气味空间的结构化表征，突出气味关系；这种表现形式在个体之间是相似的，但仍然具有可塑性，这表明嗅觉系统可以通过这种方式将相关的气味线索分配给常见但个性化的感知。梨状皮质及其来自嗅球的感觉输入都代表化学气味关系，但皮质重塑从感觉外围继承的关系信息，以增强气味泛化和反映经验。因此，皮层积极构建化学气味空间的结构化表征，突出气味关系；这种表现形式在个体之间是相似的，但仍然具有可塑性，这表明嗅觉系统可以通过这种方式将相关的气味线索分配给常见但个性化的感知。梨状皮质及其来自嗅球的感觉输入都代表化学气味关系，但皮质重塑从感觉外围继承的关系信息，以增强气味泛化和反映经验。提出了一种方法，嗅觉系统可以通过这种方法将相关的气味线索分配给常见但个性化的感知。梨状皮质及其来自嗅球的感觉输入都代表化学气味关系，但皮质重塑从感觉外围继承的关系信息，以增强气味泛化和反映经验。提出了一种方法，嗅觉系统可以通过这种方法将相关的气味线索分配给常见但个性化的感知。梨状皮质及其来自嗅球的感觉输入都代表化学气味关系，但皮质重塑从感觉外围继承的关系信息，以增强气味泛化和反映经验。