The cerebral cortex is gray matter, consisting mainly of cell bodies (with astrocytes being the most abundant cell type in the cortex as well as the human brain as a whole) and capillaries.It contrasts with the underlying white matter, consisting mainly of the white myelinated sheaths of neuronal axons.he cerebral cortex plays a key role in memory, attention, perception, awareness, thought, language, and consciousness. The human cerebral cortex is 2 to 4 millimetres (0.079 to 0.157 in) thick. In large mammals, the cerebral cortex is folded, giving a much greater surface area in the confined volume of the skull.