title: Maintaining accuracy at the expense of speed: stimulus similarity defines odor discrimination time in mice.
abstract: Odor discrimination times and their dependence on stimulus similarity were evaluated to test temporal and spatial models of odor representation in mice. In a go/no-go operant conditioning paradigm, discrimination accuracy and time were determined for simple monomolecular odors and binary mixtures of odors. Mice discriminated simple odors with an accuracy exceeding 95%. Binary mixtures evoking highly overlapping spatiotemporal patterns of activity in the olfactory bulb were discriminated equally well. However, while discriminating simple odors in less than 200 ms, mice required 70-100 ms more time to discriminate highly similar binary mixtures. We conclude that odor discrimination in mice is fast and stimulus dependent. Thus, the underlying neuronal mechanisms act on a fast timescale, requiring only a brief epoch of odor-specific spatiotemporal representations to achieve rapid discrimination of dissimilar odors. The fine discrimination of highly similar stimuli, however, requires temporal integration of activity, suggesting a tradeoff between accuracy and speed.
authors.affiliation: WIN Group of Olfactory Dynamics, Heidelberger Akademie der Wissenschaften and Max-Planck-Institut für medizinische Forschung, Jahnstrasse 29, D-69120 Heidelberg, Germany.
authors.forename: Nixon M
authors.initials: NM
authors.lastname: Abraham
authors.forename: Hartwig
authors.initials: H
authors.lastname: Spors
authors.forename: Alan
authors.initials: A
authors.lastname: Carleton
authors.forename: Troy W
authors.initials: TW
authors.lastname: Margrie
authors.forename: Thomas
authors.initials: T
authors.lastname: Kuner
authors.forename: Andreas T
authors.initials: AT
authors.lastname: Schaefer
mesh_terms: D000818:Animals; D001931:Brain Mapping; D003216:Conditioning, Operant; D004192:Discrimination, Psychological / Q000502:physiology*; D005260:Female; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009812:Odorants; D009830:Olfactory Bulb / Q000502:physiology*; D011930:Reaction Time; D012903:Smell / Q000502:physiology*; D013268:Stimulation, Chemical