Mouse olfactory system acts as anemo-detector and anemo-discriminator

Airflow detection while smelling is a fundamental requirement for olfaction, yet the mechanisms underlying such multimodal processing in the olfactory system remain unknown. We report here that mice can accurately discriminate airflow in the absence of whiskers. Modulated sniffing and refined calcium signaling in the olfactory bulb inhibitory network during olfactory anemo-discriminations confirmed the orthonasal airflow information processing. Genetic perturbation of AMPAR function and optogenetic control bidirectionally shifted the anemo-discrimination learning pace, with contrasting phenotypes observed for odor learning, engagement of inhibitory circuits, and setting the optimal inhibition level for stimulus refinement. Enhanced learning caused by multimodal odor-airflow stimuli at subthreshold levels confirmed the heightened olfactory perception by mechanical stimuli. Our results thus explain the multimodality of olfaction and reveal the unexplored dimensionality of odor perception.