title: Evolution of pain theories.
mesh_terms: D049673:History, 20th Century; D006801:Humans; D008564:Membrane Potentials; D008962:Models, Theoretical; D009424:Nervous System Physiological Phenomena; D009474:Neurons / Q000502:physiology; D010146:Pain / Q000266:history; D011603:Psychophysiology; D009435:Synaptic Transmission