white matter


Definition of white matter

: neural tissue especially of the brain and spinal cord that consists largely of myelinated nerve fibers bundled into tracts, has a whitish color, and typically underlies the cortical gray matter

Examples of white matter in a Sentence

Recent Examples on the Web The next article in this series focuses on the consequences of such sustained microglial reactivity, particularly in the white matter regions of the brain. William A. Haseltine, Forbes, 1 Aug. 2022 This change in brain health included lower total gray matter volume, abnormal white matter volume, and lower gray matter blood flow. Christina Crawford, Health.com, 19 Apr. 2022 Domenech’s brother Colin, who turns 28 on April 30, was born without the band of white matter that connects the two hemispheres in the brain, a condition called agenesis of the corpus callosum. Edward Lee, Baltimore Sun, 16 Apr. 2022 The study, published this month in Frontiers in Neural Circuits, is the first to detail and investigate structural changes in white matter after space travel. Elizabeth Gamillo, Smithsonian Magazine, 24 Feb. 2022 Their brains showed fluid shifts—our brains are about 80 percent water—and an increase of gray and white matter in the brain, reports David Nield for Science Alert. Elizabeth Gamillo, Smithsonian Magazine, 24 Feb. 2022 In a paper published last year, O’Connor and her colleagues found that brain scans measuring things like the diffusion of water through white matter in the brain could accurately distinguish ADHD with and without prenatal alcohol exposure. Emma Yasinkski, Smithsonian Magazine, 15 Feb. 2022 In addition, white matter, the insulation on axons – long cables that carry electrical impulses between nerve cells – is also less intact in older adults. Jessica Bernard, Scientific American, 22 Sep. 2021 Bell, then 27, had sustained multiple brain bleeds and microscopic tears in his brain’s white matter, a result of shearing that occurred when his brain suddenly shifted directions, said his former wife, Sunrise. New York Times, 4 Jan. 2022 See More

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

First Known Use of white matter

1674, in the meaning defined above

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Time Traveler for white matter

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The first known use of white matter was in 1674

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Statistics for white matter

Last Updated

5 Aug 2022

Cite this Entry

“White matter.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/white%20matter. Accessed 11 Aug. 2022.

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More Definitions for white matter

white matter


Medical Definition of white matter

: neural tissue especially of the brain and spinal cord that consists largely of myelinated nerve fibers bundled into tracts, has a whitish color, and typically underlies the gray matter

More from Merriam-Webster on white matter

Britannica.com: Encyclopedia article about white matter


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