Animal Pain pp 27-39 | Cite as

Neurophysiological Mechanisms of Nociception

  • Ainsley Iggo


It can be confidently predicted that neurophysiological mechanisms of nociception in the central nervous system incorporate features consistent with the specialization of the peripheral sensory receptor mechanisms described by Dr. Kruger in chapter one of this book. However, the issue is still debated; in my opinion there is increasing evidence that a specialized pain-signaling mechanism exists within the spinal cord, although there is clearly no simple “private-line” mechanism. Furthermore I strongly maintain that pain is a sensory experience, and thus occurs with certainty in conscious humans with a functional cerebral cortex. The subcortical mechanisms are aspects of nociception—the response of the nervous system (e.g., spinal cord, brain stem, thalamus) to excitation of peripheral nociceptors. Differentiation between nociception and pain aids rational discussion of the relevant mechanisms, in part by clearly delimiting the factors to be considered.


Spinal Cord Dorsal Horn Afferent Fiber Afferent Input Dorsal Column 
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Copyright information

© American Physiological Society 1983

Authors and Affiliations

  • Ainsley Iggo
    • 1
  1. 1.Department of Veterinary PhysiologyUniversity of EdinburghEdinburghScotland

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