The present studies used the classical method of serial transections of the neuraxis to examine the neural mechanisms of injury-produced pain and morphine analgesia in the formalin test. The results showed that the behavioral response that follows formalin injection is complete within the brainstem, whereas telencephalic structures are critical for morphine to produce analgesia. In contrast, when the tail flick test, a model of noninjurious pain was used, both the behavioral response, and analgesia, were intact in the brainstem transected rat, in keeping with the current model of analgesia for this test. Brain areas classically associated with pain processing were not sufficient for morphine to produce analgesia in the formalin test. Instead, the amygdala, part of the emotion-mediating limbic system, was critical. It is argued that the formalin test may be a model of "dissociative" analgesia, in which reduction of the negative affective consequences of the pain plays a major role.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.39762 |
| Date | January 1992 |
| Creators | Matthies, Brigitte Karin |
| Contributors | Franklin, Keith (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Psychology.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001327318, proquestno: NN87550, Theses scanned by UMI/ProQuest. |
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