Olfaction as an Active Sense: Sniffing and Odor Coding
Animals actively acquire odor information by sniffing - a complex behavior that changes rapidly depending on the task at hand, the behavioral context and an animal's internal state. We are interested in how the act of sniffing shapes the initial representation of odors as well as how odor information is processed by the brain. We approach this question using novel methods for imaging activity in the awake animal as it performs odor-guided tasks. We have found that sniffing shapes the temporal dynamics, the intensity, and even the identity of receptor neuron inputs to the olfactory bulb, and so plays a key role in shaping odor coding and - perhaps - odor perception. This raises many new questions, for example: how is odor information processed differently during different sniffing behaviors? what are the mechanisms by which the parameters of a sniff alter odor representations? how and when are different sniffing behaviors expressed by the animal, and how do these behaviors adaptively shape odor representations? We are addressing these questions using imaging in the awake and anesthetized animal, electrophysiological methods, behavioral assays and computational studies.
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