- Cerebral cortex
- The outer portion of the cerebrum, a key part of the brain, consisting of layers of nerve cells and the nerve pathways that connect them. The cerebral cortex is responsible for the processes of thought, perception and memory. Nerve cells in the cerebral cortex die in Alzheimer's disease and in a number of other brain disorders. The word "cortex" is Latin for the bark of a tree. The plural of cortex is cortices. The adjective is cortical.
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cerebral cortex n the convoluted surface layer of gray matter of the cerebrum that functions chiefly in coordination of sensory and motor information called also pallium see neocortex* * *
the intricately folded outer layer of the cerebrum, making up some 40% of the brain by weight and composed of an estimated 15 thousand million neurones (see grey matter). This is the part of the brain most directly responsible for consciousness, with essential roles in perception, memory, thought, mental ability, and intellect, and it is responsible for initiating voluntary activity. It has connections, direct or indirect, with all parts of the body. The folding of the cortex provides a large surface area, the greater part lying in the clefts (sulci), which divide the upraised convolutions (gyri). On the basis of its microscopic appearance in section, the cortex is mapped into Brodmann areas; it is also divided into functional regions; including motor cortex, sensory cortex, and association area. Within, and continuous with it, lies the white matter, through which connection is made with the rest of the nervous system.* * *
cortex cerebri [TA] the thin (about 3 mm) layer or mantle of gray substance covering the surface of each cerebral hemisphere, folded into gyri that are separated by sulci. It is responsible for the higher mental functions; for visceral functions; for motor and sensory functions; for perception and behavioral reactions; and for the association and integration of these functions. Many classifications have been suggested: it has been divided into archicortex, paleocortex, and neocortex according to supposed phylogenetic and ontogenetic differences; into functional areas such as motor areas, primary receptive or receiving areas, and association areas; and into areas according to the presence of six cell layers (the isocortex) or of variable numbers and arrangements of cell and fiber layers (the allocortex). Called also pallium. See also layers of cerebral cortex.
Medical dictionary. 2011.