Parts of the brain, notably the cortex (shell) of the cerebral hemispheres, composed of nerve cells "insulated" with a coating of myelin
is central nervous tissue that is largely composed of myelinated axons These fibers are organized into fasciculi, capsules, peduncles and tracts
Regions of the central nervous system containing few neuronal cell bodies and many myelinated axons The myelin sheaths are opaque compared to surrounding regions containing mostly neuronal cell bodies (gray matter)
nerve fibers that are the site of MS lesions and underlie the gray matter of the brain and spinal cord
Whitish nerve tissue, especially of the brain and spinal cord, consisting chiefly of myelinated nerve fibers
tissue in the brain and spinal cord which appears white on gross section White matter is composed of nerve fibers sheathed in myelin
nerve tissue that is paler in color than gray matter because it contains nerve fibers with large amounts of insulating material (myelin) The white matter does not contain nerve cells In the brain, the white matter lies within the gray layer of the cerebral cortex