Anatomy of the Human Olfactory Bulb and Central Olfactory Pathways

  • M Shipley
  • P Reyes


The olfactory system subserves important functions, including the perception of flavor and smell. Although olfaction has traditionally received limited attention in both normal and pathological conditions in humans, this sensory system is now of considerable interest to neurobiologists and medical practitioners.This interest has been brought about, in part, by neuropathological investigations that described the presence of histological lesions in olfactory-related structures in Alzheimer’s disease (Ferreyra-Moyano 1989, Reyes et al. 1987, Pearson et al. 1985, Esiri and Wilcock 1984), a condition clinically characterized by progressive intellectual decline and behavioral abnormalities. Importantly, olfactory deficits have been demonstrated not only in patients with Alzheimer’s disease (Doty et al. 1987), but in ones with Parkinson’s disease (Doty et al. 1988) and schizophrenia (Hurwitz et al. 1988). These new findings suggest that the olfactory system is compromised in a number of neurodegenerative disorders. Unfortunately, our knowledge of the anatomy and physiology of the olfactory system in humans is limited and based largely on rodent and non-human primate studies. Since significant anatomical and functional variations occur between species, future work on human olfactory pathways are sorely needed.


Granule Cell Olfactory Bulb Granule Cell Layer Apical Dendrite Piriform Cortex 
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© Springer-Verlag Berlin Heidelberg 1991

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  • M Shipley
  • P Reyes

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