Pain pp 25-28 | Cite as

Segmental and Brain Stem Mechanisms

  • Sherif ZakyEmail author
  • Christine S. Zaky
  • Alaa Abd-Elsayed


There are different mechanisms that modify or modulate a pain signal along its pathway. Pain modulation occurs peripherally or centrally at the level of the spinal cord or supraspinal structures. Sensitization of the receptors can lead to hyperalgesia. Peripheral hyperalgesia can be primary or secondary. Sensitization can also occur centrally due to segmental and spinal cord mechanisms leading to facilitation of transmission of the pain signal. Central hypersensitization is commonly referred to as the “Wind-up” phenomenon. Changes in neurochemistry of the dorsal horn due to repetitive stimulation as well as recruitment of non-neuronal cells, such as astrocytes and microglial cells, are believed to play an important role in central sensitization. Inhibition occurs at both spinal and supraspinal levels due to different mechanisms. Gate control theory, concomitant release of inhibitory neurotransmitters, and descending inhibitory pathways are different mechanisms that lead to inhibition.


Pain modulation Pain processing Pain pathways 


  1. 1.
    Fields HL. Central nervous system mechanisms for control of pain transmission. In: Fields HL, editor. Pain. New York: McGraw-Hill; 1987. p. 99.Google Scholar
  2. 2.
    Dray A. Inflammatory mediators of pain. Br J Anesth. 1995;75:125–31.CrossRefGoogle Scholar
  3. 3.
    Bonica JJ. Anatomic and physiologic basis of nociception and pain. In: Bonica JJ, editor. The management of pain. 2nd ed. Philadelphia: Lea and Febiger; 1990. p. 128.Google Scholar
  4. 4.
    Cook AJ, Woolf CJ, Wall PD. Dynamic receptive field plasticity in rat spinal cord dorsal horn following C-primary afferent input. Nature. 1987;325:151.CrossRefGoogle Scholar
  5. 5.
    Wall PD, Woolf CJ. The brief and prolonged facilitatory effects of unmyelinated afferent input on the rat spinal cord are independently influenced by peripheral nerve section. Neuroscience. 1986;17:1199.CrossRefGoogle Scholar
  6. 6.
    Schnitzler M, Kilbride M, Senagone A. Effect of epidural analgesia on colorectal anastomotic healing and colonic motility. Reg Anesth. 1997;59:6–9.Google Scholar

Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Sherif Zaky
    • 1
    • 2
    Email author
  • Christine S. Zaky
    • 3
  • Alaa Abd-Elsayed
    • 4
  1. 1.Pain Management Services, Firelands Regional Medical CenterSanduskyUSA
  2. 2.Ohio UniversityAthensUSA
  3. 3.Department of Biological Sciences, Dietrich School of Arts and SciencesUniversity of PittsburghPittsburghUSA
  4. 4.Department of AnesthesiologyUniversity of Wisconsin School of Medicine and Public HealthMadisonUSA

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