White Matter

White matter is one of the two components of the central nervous system and consists mostly of glial cells and myelinated axons that transmit signals from one region of the cerebrum to another and between the cerebrum and lower brain centers. White matter tissue of the freshly cut brain appears pinkish white to the naked eye because myelin is composed largely of lipid tissue veined with capillaries. Its white color is due to its usual preservation in formaldehyde.

The other main component of the brain is grey matter (actually pinkish tan due to blood capillaries), which is composed of neurons. A third colored component found in the brain that appears darker due to higher levels of melanin in dopaminergic neurons than its nearby areas is the substantia nigra.

Note that white matter can sometimes appear darker than grey matter on a microscope slide because of the type of stain used.

White matter, long thought to be passive tissue, actively affects how the brain learns and dysfunctions. Whilst grey matter is primarily associated with processing and cognition, white matter modulates the distribution of action potentials, acting as a relay and coordinating communication between different brain regions.

Read more about White MatterMyelinated Axon Length, Function, Location, Types of Astrocytes, Clinical Relevance

Other articles related to "white matter, matter, white":

White Matter - Clinical Relevance
... Multiple Sclerosis (MS) is one of the most common diseases which affect white matter ... Changes in white matter known as amyloid plaques are associated with Alzheimer's disease and other neurodegenerative diseases ... White matter injuries ("axonal shearing") may be reversible, while gray matter regeneration is less likely ...
Leukoencephalopathy With Vanishing White Matter - Neuropathology
... The gray matter remains normal in all characteristics while the white matter changes texture, becoming soft and gelatinous ... Rarefaction of the white matter is seen through light microscopy and the small number of axons and U-fibers that were affected can also be seen ... Numerous small cavities in the white matter are also apparent ...
Leukoaraiosis
... Leukoaraiosis describes the nonspecific changes in the cerebral white matter frequently seen on CT and MRI in aged individuals ... in 1986 as a descriptive term for rarefaction ("araiosis") of the white matter, showing up as decreased density on CT and increased signal intensity on T2/FLAIR sequences performed as part of ... These white matter changes are also commonly referred to as periventricular white matter disease, or white matter hyperintensities (WMH) due to their bright white appearance on T2 MRI scans ...
Pathophysiology Of Multiple Sclerosis - Blood–brain Barrier Disruption - In Vivo BBB Study
... As lesions appear (using MRI) in "Normal-appearing white matter" (NAWM), the cause that finally triggers the BBB disruption is supposed to be there ... The damaged white matter is known as "Normal-appearing white matter" (NAWM) and is where lesions appear ... They appear in active white matter lesions, and gray matter in SPMS ...
Leukoencephalopathy With Vanishing White Matter - Diagnosis - MRI
... These MRIs display a very characteristic reversal of signal intensity of the white matter in the brain ... Recovery sequences and holes in the white matter are also visible ... at showing rarefaction and cystic degeneration of the white matter as it is replaced by fluid ...

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