SINCE 1828
sympathetic nervous system
nounDefinition of sympathetic nervous system
: the part of the autonomic nervous system that contains chiefly adrenergic fibers and tends to depress secretion, decrease the tone and contractility of smooth muscle, and increase heart rate — compare parasympathetic nervous system
Examples of sympathetic nervous system in a Sentence
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The sympathetic nervous system makes sure the small blood vessels in your body’s tissue maintain a baseline level of constriction. — Anne R. Crecelius, The Conversation, "Why do people faint?," 20 June 2019 That's when your sympathetic nervous system triggers your brain to release of a bunch of hormones, including adrenaline and noradrenaline, that rev your body up. — Stephanie Dolgoff, Good Housekeeping, "Is It an Anxiety Attack or a Panic Attack? Here’s How to Know, According to Experts," 14 June 2019 The whole idea is to move from the sympathetic nervous system, fight or flight, to the parasympethic system, rest and digest. — Nina Sovich, WSJ, "The New Outdoor Getaway: Landscapes That Have Been ‘Rewilded’," 20 Sep. 2018 Every part of you, from your head to your stomach to your feet, has nerves to regulate important processes, which is why your sympathetic nervous system’s stress response can be so far-reaching. — Brittany Risher, SELF, "This Is When to See a Mental Health Professional About Your Anxiety," 2 Feb. 2018 Sympathetic tone refers to the activation of the sympathetic nervous system, which also results in the constriction of blood vessels. — Mark Lieber, CNN, "Brain effects of 'hottest pepper in the world' put man in hospital," 9 Apr. 2018 This produces a stress response in your body—specifically, your brain’s hypothalamus triggers your sympathetic nervous system to release norepinephrine (aka adrenaline) and cortisol (a stress hormone) to get you out of harm’s way. — Brittany Risher, SELF, "This Is When to See a Mental Health Professional About Your Anxiety," 2 Feb. 2018 Your sympathetic nervous system, which causes blood vessels to narrow, is the source of this mechanism. — Zahra Barnes, SELF, "Raynaud’s Disease: Why Your Hands and Feet Hurt So Badly When They’re Cold," 15 Dec. 2017 Most researchers agree that rest is a physiological state during which your innate fight-or-flight stress response, or sympathetic nervous system, subsides in favor of a more relaxed condition. — Brad Stulberg, The Cut, "How to Actually Get Some Rest for Once," 4 Oct. 2017These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sympathetic nervous system.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
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