suprachiasmatic nucleus

noun
su·​pra·​chi·​as·​mat·​ic nucleus | \ ˌsü-prə-ˌkī-əz-ˈma-tik- How to pronounce suprachiasmatic nucleus (audio) \

Definition of suprachiasmatic nucleus

: either of a pair of neuron clusters in the hypothalamus situated directly above the optic chiasma that receive photic input from the retina via the optic nerve and that regulate the body's circadian rhythms

Examples of suprachiasmatic nucleus in a Sentence

Recent Examples on the Web Our mastermind’s lair is a compartment of the brain called the suprachiasmatic nucleus (S.C.N.), containing only 50,000 of the 86 billion neurons in our body. New York Times, "Circadian Rhythms: The Conductor of Our Body’s Symphony," 7 May 2020 For years, the cells of the suprachiasmatic nucleus were thought to be alone in having their own clock, controlling all the rhythms in the rest of the body remotely. Quanta Magazine, "How the Body’s Trillions of Clocks Keep Time," 15 Sep. 2015 Just a year later, researchers reported that a tiny patch of cells in the brain called the suprachiasmatic nucleus was necessary for a 24-hour circadian rhythm in mammals. Quanta Magazine, "How the Body’s Trillions of Clocks Keep Time," 15 Sep. 2015 The part of the brain that controls circadian timing is the suprachiasmatic nucleus within the hypothalamus. SELF, "We Asked a Doctor How Much You Need to Care About Your Circadian Rhythm," 4 Sep. 2018 Exposure to bright light stimulates the brain’s master clock — the suprachiasmatic nucleus — to wind back those three-tenths of an hour. Brian Resnick, Vox, "Why being a night owl may lead to earlier death," 27 Apr. 2018 Bright light, meanwhile, is known to alter the rhythms of the suprachiasmatic nucleus, as well as boosting activity in emotion-processing areas of the brain more directly. Linda Geddes, Smithsonian, "A Counterintuitive Idea for Treating Severe Depression: Stay Awake," 23 Jan. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'suprachiasmatic nucleus.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of suprachiasmatic nucleus

1938, in the meaning defined above

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The first known use of suprachiasmatic nucleus was in 1938

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Cite this Entry

“Suprachiasmatic nucleus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/suprachiasmatic%20nucleus. Accessed 9 Aug. 2020.

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More Definitions for suprachiasmatic nucleus

suprachiasmatic nucleus

noun

Medical Definition of suprachiasmatic nucleus

: either of a pair of neuron clusters in the hypothalamus situated directly above the optic chiasma that receive photic input from the retina via the optic nerve and that regulate the body's circadian rhythms abbreviation SCN

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