Mouse olfactory system acts as anemo-detector and -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 learn to accurately discriminate airflow with parallel processing of both mechanical and chemical stimuli revealed by modulated sniffing and refined calcium signaling in the olfactory bulb inhibitory network. Genetic perturbation of AMPAR function and optogenetic control bidirectionally shifted airflow discrimination learning pace, with contrasting phenotypes observed for odor learning, engagement of inhibitory circuits, and setting the optimal inhibition level for stimulus refinement. Multimodal odor-airflow stimuli at subthreshold levels enhanced learning, demonstrating that mechanical stimuli heighten olfactory perception. Our results, thus explain the multimodality of olfaction, and reveal an unexplored dimensionality of odor perception.