title: Neuropathic pain: an evolutionary hypothesis.
abstract: BACKGROUND
  Whereas nociceptive pain has a clear survival value, the evolutionary origins of neuropathic pain remains unexplained.
  
  
  OBJECTIVE
  It is argued that neuropathic pain is an adaptation that has evolved to detect non-specific damage to the nervous system, and that it operates on the same principles of an analogous hypothesis that has been put forward to explain the evolutionary utility of motion sickness. Whereas motion sickness has been proposed to arise from an inappropriate activation of a system evolved to respond to incoherence between vestibular and visual reference frames as an indication of acute neurotoxicity, it is proposed that neuropathic pain arises from the activation of a system evolved to respond to incoherence between proprioceptive and motor outputs as an indication of nerve trauma.
  
  
  CONCLUSIONS
  Evidence that supports this hypothesis is reviewed, followed by conclusions regarding consequences for pain theory and management.
authors.affiliation: Department of Pharmacology & Toxicology, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand. john.ashton@otago.ac.nz
authors.forename: John C
authors.initials: JC
authors.lastname: Ashton
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D005075:Biological Evolution; D004525:Efferent Pathways / Q000503:physiopathology; D006801:Humans; D008959:Models, Neurological; D009437:Neuralgia / Q000209:etiology* / Q000503:physiopathology; D059348:Peripheral Nerve Injuries / Q000150:complications / Q000503:physiopathology; D011434:Proprioception / Q000502:physiology