Operationally-deployed canine detectors are often trained on one or a limited number of materials representing a single target odor, and training frequently occurs using materials of a high purity grade in controlled scenarios with minimal other background odors. Conversely, in the field, canine detectors are expected to generalize and identify variations of the target odor, while discriminating from similar extraneous or background odors. This exemplifies the balance between generalization and discrimination required for effective canine detectors. This research explored the tendency for detection canines to generalize or discriminate between similar odorants. Two groups of related odorants were used in two separate studies; (1) odorants of similar functional groups with differing carbon chains, and (2) odorants of similar carbon chain length but differing functional groups. Within each odorant set, the effect of training was addressed by incrementally increasing the number of odorants each canine was trained to detect. Initially, discrimination increased with increasing molecular dissimilarity in both odorant groups. After further training on additional related odorants, generalization increased across the set of odorants of the same carbon chain length, but there were no significant changes in either generalization or discrimination across the set of odorants of the same functional group. The results suggest that the canines in this study were more likely to generalize across compounds of the same chain length with differing functional group than across compounds of the same functional group, but differing chain lengths. Furthermore, some variation in performance between individual canines indicated that the tendency to generalize differed with experience, breed, and other factors affecting olfaction.

中文翻译：

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检测犬中分子相似气味的泛化和鉴别以及训练的影响

操作部署的犬类检测器通常针对一种或有限数量的代表单一目标气味的材料进行训练，并且经常在受控场景中使用高纯度等级的材料进行训练，其他背景气味最小。相反，在现场，犬类检测器有望概括和识别目标气味的变化，同时区分类似的外来或背景气味。这体现了有效犬类检测器所需的泛化和辨别之间的平衡。这项研究探索了检测犬类概括或区分相似气味的趋势。在两个独立的研究中使用了两组相关的气味剂；(1) 具有不同碳链的相似官能团的气味剂，(2) 碳链长度相似但官能团不同的气味剂。在每个气味组中，通过逐渐增加每只犬接受训练检测的气味的数量来解决训练的影响。最初，区分度随着两个气味组中分子差异的增加而增加。在对其他相关气味剂进行进一步培训后，相同碳链长度的气味剂组的泛化性增加，但相同官能团的一组气味剂的泛化性或区分性没有显着变化。结果表明，与具有相同官能团但链长不同的化合物相比，本研究中的犬科动物更有可能在具有不同官能团的相同链长的化合物中进行泛化。此外，