title: Complementary codes for odor identity and intensity in olfactory cortex.
abstract: The ability to represent both stimulus identity and intensity is fundamental for perception. Using large-scale population recordings in awake mice, we find distinct coding strategies facilitate non-interfering representations of odor identity and intensity in piriform cortex. Simply knowing which neurons were activated is sufficient to accurately represent odor identity, with no additional information about identity provided by spike time or spike count. Decoding analyses indicate that cortical odor representations are not sparse. Odorant concentration had no systematic effect on spike counts, indicating that rate cannot encode intensity. Instead, odor intensity can be encoded by temporal features of the population response. We found a subpopulation of rapid, largely concentration-invariant responses was followed by another population of responses whose latencies systematically decreased at higher concentrations. Cortical inhibition transforms olfactory bulb output to sharpen these dynamics. Our data therefore reveal complementary coding strategies that can selectively represent distinct features of a stimulus.
authors.affiliation: Department of Neurobiology, Duke University Medical School, Durham, United States.
authors.forename: Kevin A
authors.identifier: 0000-0002-2271-5280
authors.initials: KA
authors.lastname: Bolding
authors.affiliation: Department of Neurobiology, Duke University Medical School, Durham, United States.
authors.forename: Kevin M
authors.identifier: 0000-0002-6386-9518
authors.initials: KM
authors.lastname: Franks
mesh_terms: D000200:Action Potentials; D000818:Animals; D051379:Mice; D009474:Neurons / Q000502:physiology*; D009812:Odorants; D055696:Olfactory Perception; D066195:Piriform Cortex / Q000502:physiology*
keywords: mouse; neuroscience; odor coding; piriform cortex; sensory processing