WHOLE-BRAIN ENCODING OF OPPOSITE-SEX ODORS IN LABORATORY AND WILD MICE

Sexual imprinting is a form of learned mate preference in which individuals develop attraction (positive) or avoidance (negative) to traits observed during their early social environment. These preferences shape adult mate choice. In rodents, olfaction is the major sensory modality and plays an important role in regulating social behaviors, particularly in mate selection. Here, we performed whole-brain analyses of females reared with and without their fathers and then exposed to familiar (father-exposed) and unfamiliar (novel) olfactory stimuli. We also measured females’ behavior during stimulus exposure, to correlate brain activation with behavioral performance. For generalisation and ecological validation, we compared C57BL/6J laboratory females with wild house mice.Neuronal activity was measured using whole-brain immunolabeling for the immediate early gene c-Fos. Brains were cleared, imaged by light-sheet fluorescence microscopy, and registered to a brain atlas for whole-brain analysis.Our results show clear differences between laboratory and wild mice in both recruited brain areas and behavior. Laboratory mice actively interact with stimuli, whereas wild mice show less interaction overall, with increased contact toward familiar compared to novel odor cues. Differences in behavior correlate with differences in brain activation. Although there is an overall overlap in recruited macro-regions between experimental groups, wild mice show reduced activation levels and selective recruitment of distinct subregions. Brain activation correlates well with behavioral performance in laboratory and wild mice, revealing distinct strategies for odor-driven social decision-making and providing insight into the neural basis of learned mate preferences.