white matter


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Related to white matter: gray matter

matter

 [mat´er]
1. physical material having form and weight under ordinary conditions; called also substance.
2. pus.
gray matter areas of the nervous system where the nerve fibers are unmyelinated (not enveloped by a myelin sheath); it contains the bodies of the nerve cells. Tissue composed of myelinated fibers is called white matter. The cerebral cortex is entirely composed of gray matter and the cerebellum also contains some deep-seated masses of it. The spinal cord has a central core of gray matter surrounded by white matter; in cross section, its gray matter is shaped approximately like the letter H. Called also substantia grisea and gray substance.
white matter areas of the nervous system composed mostly of myelinated nerve fibers (those having myelin sheaths) constituting the conducting portion of the brain and spinal cord. Tissue composed of unmyelinated fibers is called gray matter. Called also substantia alba and white substance.

white mat·ter

[TA]
those regions of the brain and spinal cord that are largely or entirely composed of nerve fibers and contain few or no neuronal cell bodies or dendrites.

white matter

n.
Whitish nerve tissue, especially of the brain and spinal cord, consisting chiefly of myelinated nerve fibers.

white mat·ter

(wīt mat'ĕr) [TA]
Those regions of the brain and spinal cord that are largely or entirely composed of nerve fibers and contain few or no neuronal cell bodies or dendrites.
Synonym(s): substantia alba, white substance.

white matter

Those parts of the central nervous system that appear white on section because they consist mainly of myelinated nerve fibres. Compare grey matter which consists mainly of nerve cell bodies.

white matter

the tissue of the CENTRAL NERVOUS SYSTEM, lying outside the GREY MATTER in the spinal cord but internal to grey matter in the brain of some vertebrates, and which contains the myelinated AXONS of nerves. The MYELIN SHEATHS give the tissue its white appearance.
References in periodicals archive ?
Reneman also said the results couldn't be generalized to mean that girls with ADHD would experience the same white matter changes from the drug, "as girls differ considerably in brain white matter development."
van der Knaap, "Leukoencephalopathy with vanishing white matter: from magnetic resonance imaging pattern to five genes," Journal of Child Neurology, vol.
On the other hand, schizophrenia patients may also show white matter disintegrity even in very early stages (9), and some of these white matter changes were also reported to correlate with clinical measures as neurocognitive symptoms and negative symptoms (10, 11).
Our findings indicate the need for suspecting neurobrucellosis as a cause of epilepsy and white matter disease in immunocompromised patients in disease-endemic areas.
With respect to cortical regions in uncomplicated alcoholism, various methods have shown significant, widespread shrinkage of both cortical gray and white matter with corresponding increases in CSF-filled spaces (Cardenas et al.
Table 2 shows the total volumes for gray and white matter. As can be seen no significant differences were found between OCD and NCC in the total gray t (28)= -1.13, p= .266 or white matter volumes t (28)= -.46, p= .643.
The General Epidemiology of White Matter Injury after Hypertensive ICH.
Brain MRI often showed pronounced changes involving cerebral and cerebellar white matter and the deep gray nucleus.
The crude model also found that both diabetes groups had significantly lower white matter volume than did the healthy subjects.
Alexander's disease with Megalencephaly and Periventricular T2 white matter hyperintensities in the bilateral frontal region was seen in one case.
The team then calculated how white matter volume related to age across the two groups.
By looking at weight and measuring their white matter through MRI scans-and taking variables like gender and self-reported health issues into account-the researchers found those with extra pounds had less white matter than their leaner peers.