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Animals can assign novel odours to a known category

Wright, Hannah F., Wilkinson, Anna, Croxton, Ruth, Graham, Deanna K., Harding, Rebecca C., Hodkinson, Hayley L., Keep, Benjamin, Cracknell, Nina R. and Zulch, Helen E. (2017) Animals can assign novel odours to a known category. Scientific Reports, 7 (1). ISSN 2045-2322

Item Type: Article


The ability to identify a novel stimulus as a member of a known category allows an organism to respond appropriately towards it. Categorisation is thus a fundamental component of cognition and an essential tool for processing and responding to unknown stimuli. Therefore, one might expect to observe it throughout the animal kingdom and across sensory domains. There is much evidence of visual categorisation in non-human animals, but we currently know little about this process in other modalities. In this experiment, we investigated categorisation in the olfactory domain. Dogs were trained to discriminate between 40 odours; the presence or absence of accelerants formed the categorical rule. Those in the experimental group were rewarded for responding to substrates with accelerants (either burnt or un-burnt) and inhibit responses to the same substrates (either burnt or un-burnt) without accelerants (S+ counterbalanced). The pseudocategory control group was trained on the same stimuli without the categorical rule. The experimental group learned the discrimination and animals were able to generalise to novel stimuli from the same category. None of the control animals were able to learn the discrimination within the maximum number of trials. This study provides the first evidence that non-human animals can learn to categorise non-biologically relevant odour information.

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Depositing User: Ruth Croxton


Item ID: 16566
Identification Number:
ISSN: 2045-2322
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ORCID for Ruth Croxton: ORCID iD

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Date Deposited: 27 Feb 2024 08:55
Last Modified: 27 Feb 2024 09:00


Author: Ruth Croxton ORCID iD
Author: Hannah F. Wright
Author: Anna Wilkinson
Author: Deanna K. Graham
Author: Rebecca C. Harding
Author: Hayley L. Hodkinson
Author: Benjamin Keep
Author: Nina R. Cracknell
Author: Helen E. Zulch

University Divisions

Faculty of Health Sciences and Wellbeing > School of Psychology


Sciences > Chemistry

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