The cerebral cortex, also known as the cerebrum, is the largest portion of the brain, located right under the forehead and it is divided into two parts, a right and a left hemisphere.They in turn have a total of four lobes – the frontal, parietal, temporal and occipital lobes.he cerebral cortex, also known as the cerebrum, is the largest portion of the brain, located right under the forehead and it is divided into two parts, a right and a left hemisphere.