The external layer of gray matter that covers the human brain hemispheres. This gray surface has a thickness varying from 1 to 4 mm. Its largest part is composed of neurons, which receive and transmit electrical impulses from and to other brain regions and bony parts. The cerebral cortex is the part of the brain in which thought processes take place. In Alzheimer’s disease, nerve cells in the cerebral cortex die.
The outermost layer of gray matter of the cerebral hemisphere.
The outer layer of grey matter which covers the cerebrum.
Thin layer of gray matter, with many folds on the surface of the cerebrum, that is the center for higher mental functions, perception, behavioral responses, and other functions. It is classified into many areas, each with specific functions (e.g., speech center).
Outer layer of the cerebrum.
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 neurons. 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 areas. Within, and continuous with it, lies the white matter, through which connection is made with the rest of the nervous system.
The thin, convoluted surface layer of gray matter of the cerebral hemispheres (the cerebrum), consisting principally of cell bodies of neurons arranged in layers, as well as numerous fibers. Most of the cerebral cortex has six histologically distinct horizontal cortical layers. From superficial to deep they are: 1. molecular layer (horizontal axons, Golgi type II cells, dendrites of underlying pyramidal cells); 2. external granular layer (closely packed small granule cells); 3. external pyramidal layer (pyramidal neurons, granule cells, Martinotti cells); 4. internal granular layer (closely packed stellate cells); 5. internal pyramidal layer (pyramidal neurons, granule cells, Martinotti cells); and 6. multiform (fusiform) layer (spindle-shaped cells).
Deep within the intricate folds of our cerebral landscape, a remarkable domain emerges—a sanctuary dedicated to the realms of reason, mood, and perception. This distinguished realm, known as the frontal cortex, assumes a commanding role in the delicate orchestration of our cognitive faculties, the subtle nuances of our emotional tapestry, and the wondrous realm of sensory interpretation. It stands as a testament to the awe-inspiring complexity and profound capabilities of the human brain.