Odorant Detection and Discrimination in the Olfactory System

  • Simone Pifferi
  • Anna Menini
Conference paper
Part of the Lecture Notes in Electrical Engineering book series (LNEE, volume 91)


The olfactory system excels in both discrimination and detection of odorants. In mammals, it reliably discriminates more than 3000 structurally diverse odorant molecules and has an amazingly high sensitivity that allows the detection of very low amounts of specific odorant molecules. In addition, the olfactory system has the capability to adapt to ambient odorants, allowing the recognition of a broad range of stimuli. The discrimination among different odorants is achieved by using hundreds of receptors, activated with a combinatorial code. Olfactory transduction uses a canonical second messenger system providing two critical attributes: amplification and high signal-to-noise characteristics, giving the system its remarkable detector capabilities. In this review, we present an introduction to the basic molecular mechanisms of olfactory transduction in olfactory sensory neurons.


Olfactory Epithelium Olfactory System Odorant Receptor Olfactory Sensory Neuron Odorant Stimulus 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  1. 1.Scuola Internazionale Superiore di Studi Avanzati, SISSA, and Italian Institute of Technology, SISSA UnitTriesteItaly

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