While the brain is the master controller, the nervous system also has local control points. For example, a burn reflex travels to and from the spinal cord so that you withdraw your hand before your brain knows what happened.
Nerves carry messages differently than copper wire carries electricity.
Like a string of interlinked batteries, each nerve is chained to others and normally only has to send a signal a short distance to a neighbor. The neighbor then fires the message along the line to another. These messages can be transferred up to 400 feet per second throughout the body. The nervous system includes about 28 billion cells. The basic function of the nervous system is to trigger and monitor all communication processes in the body.