Title: unconditioned stimulus
Long Title: IUPAC Gold Book - unconditioned stimulus
DOI: 10.1351/goldbook.12096
Status: current

Definition
Stimulus that automatically elicits a paired response, such as food eliciting salivation in a hungry animal.

Related Terms
- Stimulus: https://goldbook.iupac.org/terms/view/12094
- conditioned stimulus: https://goldbook.iupac.org/terms/view/12095

Source
- PAC, 2015, 87, 841. 'IUPAC Glossary of terms used in neurotoxicology (IUPAC Recommendations 2015)' on page 907 (https://doi.org/10.1515/pac-2015-0103)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/12096/html
- json: https://goldbook.iupac.org/terms/view/12096/json
- xml: https://goldbook.iupac.org/terms/view/12096/xml

Citation: Citation: 'unconditioned stimulus' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.12096
License: The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms.
Collection: If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org .
Disclaimer: The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.
Accessed: 2026-06-30T10:26:50+00:00