Maintaining Accuracy at the Expense of Speed: Stimulus Similarity Defines Odor Discrimination Time in Mice

Neuron. 2004 Dec 2;44(5):865-76. doi: 10.1016/j.neuron.2004.11.017.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brain Mapping
  • Conditioning, Operant
  • Discrimination, Psychological / physiology*
  • Female
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Odorants*
  • Olfactory Bulb / physiology*
  • Reaction Time
  • Smell / physiology*
  • Stimulation, Chemical