white matter

noun

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

Returning to Earth helped the gray matter mostly bounce back but seemed to cause shrinkage in white matter, which connects parts of the brain. National Geographic, "What happens to brains in space, and more breakthroughs," 12 June 2019 The researchers also imaged the study participants’ brains to look for differences in brain volumes as well as changes to the white matter that insulates the brain’s biological wiring. Rachel Becker, The Verge, "Don’t stress out yet about stress shrinking your brain," 25 Oct. 2018 In 2014 a study showed that for mice, novel experiences prompt almost immediate changes in white matter—the brain’s connective tissue, or highway system. Susan Pinker, WSJ, "New Skills Build New Brain Architecture, Research Shows," 14 June 2018 When a wild rabbit is in danger, more white matter is needed for faster reflexes and for learning what to be afraid of. Elizabeth Gamillo, Science | AAAS, "Why your pet rabbit is more docile than its wild relative," 25 June 2018 While most business leaders who have spoken out have expressed strong disagreement over the immigration issue, not all view it as a black-and-white matter. Monica Rodriguez, Fortune, "Business Leaders Denounce Family Separations at U.S. Border," 19 June 2018 Eden explains that the image illustrates the white matter pathways in the brain. Lisa Wood Shapiro, WIRED, "The End of Dyslexia," 18 June 2018 After many specialist visits and tests, an MRI found damage to the nerve fibers, or white matter, in her brain. Sumathi Reddy, WSJ, "The ‘Right to Try’ Law Says Yes, the Drug Company Says No," 6 June 2018 Two of these sheets, highly folded, along with their hundreds of millions of wires—the white matter—are crammed into the skull. Christof Koch, Scientific American, "What Is Consciousness?," 8 May 2018

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.

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First Known Use of white matter

1674, in the meaning defined above

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Last Updated

28 Jun 2019

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The first known use of white matter was in 1674

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More Definitions for white matter

white matter

noun

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

Rhyming Dictionary: Words that rhyme with white matter

Britannica.com: Encyclopedia article about white matter

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