What Is the Nervous System? Your nervous system is your body's main communication system. It sends messages from your brain to the rest of your body and helps you respond to changes inside and ...

The sympathetic nervous system becomes more active during times of stress, and for some people, this activation can become excessive or prolonged.

These move towards the central nervous ... system. Receptors are groups of specialised cells. They detect a change in the environment and stimulate electrical impulses in response. Sense organs ...