Assessment of direct knowledge of the human olfactory system.

The olfactory system is highly conserved across mammalian species (Ache and Young, 2005; Gelperin, 1999; Hildebrand and Shepherd, 1997; Laurent, 2002). In particular, the human and rodent olfactory systems share numerous common traits, including the basic organization of the olfactory central nervous system, aspects of odor guided behaviors, the nature of odorant receptor proteins, and processing at the molecular and synaptic levels (Fig. 1). These shared characteristics make rodents an excellent model for use in understanding the human olfactory system and has led to widespread use of rodents in olfactory studies. As a result, knowledge of the rodent olfactory system is expansive, and has been the primary guide to human olfactory research for decades. Though the olfactory systems of the two species are highly similar (Ache and Young, 2005), some differences are apparent (Mainland et al., 2014; Maresh et al., 2008; McGann, 2017; Trimmer et al., 2019), and direct data from humans is lacking. Our current understanding of the human olfactory system relies substantially on inferences from direct knowledge obtained in rodents. Inferring from rodents is well justified, and has moved the field of human olfaction forward. However, within the growing human olfaction literature, it is often unclear which statements are inferred from rodent work, and which are directly from human data. In a field dominated by rodent studies, and in order to avoid confusion and compounded misstatements, there arises a periodic need to assess the state of direct knowledge of the human olfactory system. Our goal here is to provide a thorough review of olfactory literature in order to assess and clarify our current direct knowledge of the human olfactory system, as compared to the rodent olfactory system.

• Publication year

  2020

• Venue

  Experimental Neurology

• Publication date

  2020-04-09

• Fields of study

  Biology, Medicine

• Identifiers
  DOI 10.1016/j.expneurol.2020.113304PMID 32278646PMCID PMC8063173
• External record

  Open on Semantic Scholar

• Source metadata

  Semantic Scholar, PubMed

• No claims are published for this paper.

• No concepts are published for this paper.

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