Search results
Results from the WOW.Com Content Network
White matter is the tissue through which messages pass between different areas of grey matter within the central nervous system. The white matter is white because of the fatty substance (myelin) that surrounds the nerve fibers (axons). This myelin is found in almost all long nerve fibers, and acts as an electrical insulation.
White matter tracts within a human brain, as visualized by MRI tractography Rendering of a group connectome based on 20 subjects. Anatomical fibers that constitute the white matter architecture of the human brain are visualized color-coded by traversing direction (xyz-directions mapping to RGB colors respectively). Visualization of fibers was ...
The adult human brain is estimated to contain 86±8 billion neurons, with a roughly equal number (85±10 billion) of non-neuronal cells. [41] Out of these neurons, 16 billion (19%) are located in the cerebral cortex, and 69 billion (80%) are in the cerebellum.
Brain at the U.S. National Library of Medicine Medical Subject Headings (MeSH) (view tree for regions of the brain) BrainMaps.org; BrainInfo (University of Washington) "Brain Anatomy and How the Brain Works". Johns Hopkins Medicine. 14 July 2021. "Brain Map". Queensland Health. 12 July 2022.
The uncinate fasciculus is a white matter association tract in the human brain that connects parts of the limbic system such as the temporal pole, anterior parahippocampus, and amygdala in the temporal lobe with inferior portions of the frontal lobe such as the orbitofrontal cortex.
The external capsule is a series of white matter fiber tracts in the brain. These fibers run between the most lateral (toward the side of the head) segment of the lentiform nucleus (more specifically the putamen) and the claustrum. The white matter of the external capsule contains fibers known as corticocortical association fibers.
White matter is composed mainly of myelinated axons, and takes its color from the myelin. White matter includes all of the nerves, and much of the interior of the brain and spinal cord. Gray matter is found in clusters of neurons in the brain and spinal cord, and in cortical layers that line their surfaces.
The mammalian cerebral cortex, the grey matter encapsulating the white matter, is composed of layers. The human cortex is between 2 and 3 mm thick. [11] The number of layers is the same in most mammals, but varies throughout the cortex. 6 layers can be recognized in the neocortex, although many regions lack one or more layers.