The body and the arch create a vertebral canal through which the spinal cord courses down to the level of the second lumbar vertebra. The intervertebral disks between the vertebral bodies act as elastic buffers to absorb mechanical shocks. It is composed of two major structures, the cerebrum and the basal ganglia . Its surface is made up of convolutions called gyri , which are separated by shallow and deep grooves called sulcus and fissure respectively. Although every human brain shares the presence of certain sulcus and fissure, no two brains have exactly the same pattern.
Some axons pass from one hemisphere to the other in bundles such as the large corpus callosum .
Some pass from lobe to lobe from gyrus to gyrus in the same hemisphere. Many axons , however, descend from the cortex to other areas of the central nervous system such as the spinal cord passing through an area called the internal capsule . The basal ganglia , the area for crude motor activity, are buried deep in the cerebral hemisphere. The diencephalon is located in the middle of the brain, between the two cerebral hemispheres. The hypothalamus is the area concerned with temperature, appetite and various other hormonal control.