The brain is the centre of all conscious awareness. The brain’s outer layer, the cerebral cortex, is highly developed in humans and is what distinguishes our higher mental functions from those of animals. The brain is divided into two hemispheres.
The spinal cord is an extension of the brain. It is responsible for reflex actions (e.g. pulling your hand away from a hot plate). It also passes messages to and from the brain and connects nerves to the PNS.
