The Olfactory System: Basic Anatomy and Physiology for General Otorhinolaryngologists

다국어 초록 (Multilingual Abstract)

Olfaction is one of the five basic human senses, and it is known to be one of the most primitive senses. The sense of olfac-tion may have been critical for human survival in prehistoric society, and although many believe its importance has dimin-ished over time, it continues to have an impact on human interaction, bonding, and propagation of the species. Even if weare unaware of it, the sense of smell greatly affects our lives and is closely related to overall quality of life and health. None-theless, olfaction has been neglected from a scientific perspective compared to other senses. However, olfaction has recent-ly received substantial attention since the loss of smell and taste has been noted as a key symptom of severe acute respira-tory syndrome coronavirus 2 (SARS-CoV-2) infection. Studies investigating olfaction loss in association with coronavirusdisease 2019 (COVID-19) have revealed that olfactory dysfunction can be both conductive and sensorineural, possiblycausing structural changes in the brain. Olfactory training is an effective treatment for olfactory dysfunction, suggesting thereorganization of neural associations. A reduced ability to smell may also alert suspicion for neurodegenerative or psychiat-ric disorders. Here, we summarize the basic knowledge that we, as otorhinolaryngologists, should have about the sense ofsmell and the peripheral and central olfactory pathways for managing and helping patients with olfactory dysfunction.

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