SPLTRAK Abstract Submission
Odor Identification in the Presence of Novel Backgrounds 
Yan Li, Tianyu She, Asiyah Rahman , Asim Ahmed , Jason Wu, Daniel Mogel , Gonzalo Otazu
Department of Biomedical Sciences, College of Osteopathic Medicine, New York Institute of Technology , Old Westbury, NY, United States

Rodents identify odors of interest (target odors) in natural olfactory scenes. Animals can learn to identify odors in the presence of known background odors after multiple exposures. However, it is unclear if an animal trained to recognize an odor in one background would be able to generalize this task in the presence of a different background odor or would require multiple exposures before being able to correctly identify the target odor. In order to test the generalization capability of mice, we presented awake head-fixed mice with target odors in the presence of background odors. We used intrinsic optical imaging to record dorsal glomerular activation patterns to these odor combinations (training set) and used those data to create a linear classifier for detecting the target odors. We tested the learned linear classifier with odor mixtures that included a novel background odor (test set) and found that the linear classifier performance varied between 65% and 90% accuracy for a set of 9 background odors.  We trained 9 head-fixed mice to perform a go/no-go task using the training set. Mice reached 90% performance after 8-10 days of training. We then tested the detection capability using the test set that included the novel odors.  Mice sniff rate increased when they were presented with the novel background odor indicating that the novel background was perceived as a novel odor. Mice correctly identified the target odors with the novel background odors at a rate that was consistent with the imaging data. Mice required an extra sniff to respond to the target odor and mice response times were slower in the novel odor environment compared to the responses to the training set. Our data indicates that animals are able to immediately generalize to novel odor environments.