The physiology of the nervous system can be explored at the level of a nerve cell, or [[Neurones - Anatomy & Physiology|'neuron']]. Communication between these cells uses electrical or chemical signals known as [[Neurotransmitters - Anatomy & Physiology|neurotransmitters]]; the cellular response generated in response to this signalling is known as an [[Action Potentials - Anatomy & Physiology|action potential]].