What is Nasal cycle?
[[File:Concha nasalis.gif|thumb|A [[X-ray computed tomography|CT scan]] showing evidence of the nasal cycle. The more open airway is on the right; the swollen turbinates congest the left]] The '''nasal cycle''' is the alternating partial nasal [[congestion]] and decongestion of the [[nasal cavity|nose cavities]]. It occurs in humans and other mammals. The individual is usually not aware that it happens.<ref name=huizing52>{{cite book|last1=Huizing|first1=E. H.|title=Functional reconstructive nasal surgery |url=https://archive.org/details/functionalrecons00huiz|year=2003|publisher=Thieme|isbn=978-1-58890-081-4|pages=[https://archive.org/details/functionalrecons00huiz/page/n67 52]|last2=de Groot |first2=J.A.M.}}</ref><ref name=josephson>Josephson J.S. 2006. ''Sinus relief now: the ground-breaking 5-step program for sinus, allergy, and asthma sufferers''. London, Penguin. pp. 15. ISBN 978-0-39953-298-6</ref> It results in greater airflow through one [[nostril]], and regular alternation between the nostrils. The [[hypothalamus]] selectively activates each half of the [[autonomic nervous system]] in turn. The [[phenomenon]] is quite normal. == What happens == The [[cilia]] of the congested side suspend their motility until that side decongests. The cycle means that, at any time, one side of the nose is moist, and moistens the incoming air. This is one of the three functions of the nose. The other two are the filtration and warming of fresh air before it gets to the lungs.<ref>Thomas Hummel & Antje Welge-Lüssen 2006. ''Taste and smell: an update''. Karger Medical and Scientific Publishers. ISBN 978-3-8055-8123-3</ref> It is not entirely clear what the benefit is of this system. == References == {{reflist}} [[Category:Physiology]] [[Category:Respiratory system]]