Neurons are found within the nerves of the brain, the spinal cord, parts of the peripheral nervous system, and the central nervous system. They are responsible for transmitting electric and chemical impulses within synapses found in several parts of he body. Without neurons, our bodies won't be able to react to both internal and external stimuli. Neurons are all electrically excitable and in the adult brain, they do not undergo cell division. This is partly the reason why as people age, they tend to become forgetful because of the degeneration of neuron synapses found within the brain.