Raps, D. A.; Pierce, G. M.; Papiani, G.; Wu, L.; Arroyave, R.; Brann, J. H.; Pfister, P.

How complex, multifaceted perceptual odor qualities of volatile chemicals are encoded by the olfactory system is poorly understood. We explore the receptive fields of individual odorant receptors and show how potent agonists share a consistent perceptual quality despite chemical diversity. This supports the idea that the olfactory neural connectome maintains peripheral information like odor quality through the distinct layers of the system, akin to a labeled line regime present in other sensory structures. We further observe that simple combinatorial activation of odorant receptors can generate a perceptual sum. Human olfaction may thus be shaped by the orthogonal and elemental encoding of olfactory features detected by receptor selectivity and activity. These results provide novel insights into how the brain processes olfactory information and more broadly into neural encoding during sensory processing.