The brachial plexus is a network of nerves that originate near the neck and shoulder. These nerves begin at the spinal cord in the neck and control the hand, wrist, elbow, and shoulder. Nerves are the electrical wiring system in all people that carry messages from the brain to the rest of the body. A nerve is like an electrical cable wrapped in insulation.
Motor nerves carry messages from the brain to muscles to make the body move. Sensory nerves carry messages to the brain from different parts of the body to signal pain, pressure, and temperature. The brachial plexus has nerves that are both motor and sensory.