The external information about our surroundings is sent to the brain via nerve impulses. Our nerve impulses are special signals that travel through our spinal up to our nervous systems and brain when a certain outside force causes our body to react in a certain way. These impulses help code information, and are transmitted at various speeds in respect to the human reflex ability. In short, it is a special wave or transmission of chemical activity that exists along nerve fibers which influences the reaction of a muscle. From the nerve cell, the impulse is transmitted as a signal to an effector in response to an external force.
ex. when we put our hand on a stove, our nerves react by sending impulse signals up to our brain and nervous system which in turn, give us information that our hand is burning and needs to be removed for safety.<span />
