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Open Access

Single scale for odor intensity in rodent olfaction

  • Yevgeniy Sirotin1
Flavour20143(Suppl 1):O10

Published: 16 April 2014

Central to understanding the neural basis of perception is the relationship between stimulus identity and intensity. In olfaction, odor identity can signal a food source or a predator, while intensity can provide information about its proximity or quantity. The relative intensities of odors are therefore important in guiding behavioral decisions. It is however not known how animals compare quantities of different odors. Using a novel behavioral assay assessing perceived odor intensity in rats, we found that rats measure the intensity of different odors using a common perceptual scale. Position of an odor along this intensity scale was determined by three factors: concentration, molecular weight, and the adaptation state of the animal. Our results imply that the olfactory system separates intensity and identity, forming a common intensity scale for making quantitative comparisons between different odors.

Authors’ Affiliations

Shelby White and Leon Levy Center for Mind, Brain and Behavior, Rockefeller University


© Sirotin; licensee BioMed Central Ltd. 2014

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver ( applies to the data made available in this article, unless otherwise stated.