The olfactory vector hypothesis of neurodegenerative disease: is it viable?

Ann Neurol. 2008 Jan;63(1):7-15. doi: 10.1002/ana.21327.


Environmental agents, including viruses, prions, and toxins, have been implicated in the cause of a number of neurodegenerative diseases, most notably Alzheimer's and Parkinson's diseases. The presence of smell loss and the pathological involvement of the olfactory pathways in the formative stages of Alzheimer's and Parkinson's diseases, together with evidence that xenobiotics, some epidemiologically linked to these diseases, can readily enter the brain via the olfactory mucosa, have led to the hypothesis that Alzheimer's and Parkinson's diseases may be caused or catalyzed by agents that enter the brain via this route. Evidence for and against this concept, the "olfactory vector hypothesis," is addressed in this review.

Publication types

  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Alzheimer Disease / chemically induced
  • Alzheimer Disease / physiopathology
  • Alzheimer Disease / virology
  • Animals
  • Axonal Transport
  • Disease Progression
  • Dyskinesia, Drug-Induced / physiopathology
  • Hazardous Substances / toxicity
  • Humans
  • Neurodegenerative Diseases / chemically induced*
  • Neurodegenerative Diseases / physiopathology
  • Neurodegenerative Diseases / virology*
  • Olfaction Disorders / chemically induced*
  • Olfaction Disorders / physiopathology
  • Olfaction Disorders / virology*
  • Olfactory Mucosa / drug effects
  • Olfactory Mucosa / physiopathology
  • Olfactory Mucosa / virology
  • Parkinson Disease / physiopathology
  • Parkinson Disease / virology
  • Virus Diseases / physiopathology


  • Hazardous Substances