Abstract:
Autism spectrum disorder (ASD or autism) is a neurodevelopmental condition characterized by deficits in verbal and non-verbal communication skills, narrowed interests, and repetitive behaviors. Altered sensory behaviors, such as abnormal eye tracking, temperature insensitivity, and excessive sniffing, which we will refer to as “olfactomotor” behaviors, have been identified as a common symptom in individuals with autism. Olfactomotor responses, such as sniffing, are respiratory, orofacial, and locomotive movements that allow an organism to sample and react to odors (Esquivelzeta Rabell et al., 2017; Findley et al., 2021; Johnson et al., 2003a; Jones & Urban, 2018; Kurnikova et al., 2019; Wesson et al., 2008). Neurotypical individuals modulate their sniffing behavior when presented with aversive odors, but those with ASD do not despite identifying the odors as unpleasant, suggesting an altered unconscious motor response (Rozenkrantz et al. 2015). To investigate the neural mechanisms underlying olfactomotor sampling, we investigated respiratory and orofacial responses to odor using wildtype mice. Wildtype mice were exposed to 2-phenylethanol (attractive odor), 2-methylbutyric acid (aversive odor), alpha-pinene (neutral odor), or clean air over the course of a behavioral session. We recorded respiration with an intranasal thermistor and track orofacial movements using DeepLabCut. Our preliminary results in wildtype mice (n=3) suggest that mice alter their sniffing and nose movement in response to odor stimuli. This work will shed light on active olfaction and establish the framework for testing autism model mice in the future.