The cerebral hemisphere contains four lobes: the frontal lobe which is involved in motor functions, the parietal lobe which processes sensory information, the temporal lobes which are involved in hearing, and the occipital lobe which processes visual information. Each lobe contains cortical areas that are responsible for primary sensory and motor functions or higher-level association functions. The lobes are supplied by arteries on the surface of the brain and are separated by grooves and gyri.