bioRxiv preprint doi: https://doi.org/10.1101/754374; this version posted March 31, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Odor Mixtures in Dogs’ Brains Decoding Odor Mixtures in the Dog Brain: An Awake fMRI Study 1 Ashley Prichard1, Raveena Chhibber1, Jon King1, Kate Athanassiades1, Mark Spivak2,3, & 2 Gregory S. Berns1* 3 1Psychology Department, Emory University, Atlanta, GA 30322 4 2Comprehensive Pet Therapy, Inc., Sandy Springs, GA 30328 5 3Dog Star Technologies, LLC, Sandy Springs, GA 30328 6 * Correspondence: 7 Corresponding Author: Gregory S. Berns 8
[email protected] 9 Keywords: Dog, odor, mixture, fMRI, RFC, MVPA, decoding, brain 10 Abstract 11 In working and practical contexts, dogs rely upon their ability to discriminate a target odor from 12 distracting odors and other sensory stimuli. Few studies have examined odor discrimination using 13 non-behavioral methods or have approached odor discrimination from the dog’s perspective. Using 14 awake fMRI in 18 dogs, we examined the neural mechanisms underlying odor discrimination 15 between two odors and a mixture of the odors. Neural activation was measured during the 16 presentation of a target odor (A) associated with a food reward, a distractor odor (B) associated with 17 nothing, and a mixture of the two odors (A+B). Changes in neural activation during the presentations 18 of the odor stimuli in individual dogs were measured over time within three regions known to be 19 involved with odor processing: the caudate nucleus, the amygdala, and the olfactory bulbs.