Le piu' recenti ricerche ricerca hanno rivelato che i cosiddetti placebo inducono cambiamenti biochimici e cellulari nel cervello di un paziente molto simili a quelle indotte da farmaci. Questo nuovo modo di pensare può avere profonde implicazioni sia per la sperimentazione clinica che per la pratica medica.

Curr Pain Headache Rep. 2010 vol. 14(2) pp. 124-31

Unravelling the mystery of pain, suffering, and relief with brain imaging.

Lee MC, Tracey I

In humans, the experience of pain and suffering is conveyed specifically by language. Noninvasive neuroimaging techniques now provide an account of neural activity in the human brain when pain is experienced. Knowledge gleaned from neuroimaging experiments has shaped contemporaneous accounts of pain. Within the biopsychosocial framework, nociception is undoubtedly required for survival, but is neither necessary nor sufficient for the consciousness of pain in humans. Pain emerges from the brain, which also exerts a top-down influence on nociception. In the brains of patients with chronic pain, neuroimaging has revealed subtle but significant structural, functional, and neurochemical abnormalities. Converging evidence suggests that the chronic pain state may arise from dysfunction of the frontal-limbic system. Further research in the clinical pain population will continue to identify neural mechanisms that contribute to the experience and consequence of pain, which may then be targeted therapeutically.

Nat. Med. 2010 vol. 16(11) pp. 1277-83

Getting the pain you expect: mechanisms of placebo, nocebo and reappraisal effects in humans.

Tracey I

The perception of pain is subject to powerful influences. Understanding how these are mediated at a neuroanatomical and neurobiological level provides us with valuable information that has a direct impact on our ability to harness positive and minimize negative effects therapeutically, as well as optimize clinical trial designs when developing new analgesics. This is particularly relevant for placebo and nocebo effects. New research findings have directly contributed to an increased understanding of how placebo and nocebo effects are produced and what biological and psychological factors influence variances in the magnitude of the effect. The findings have relevance for chronic pain states and other disorders, where abnormal functioning of crucial brain regions might affect analgesic outcome even in the normal therapeutic setting.

Nonopioid placebo analgesia is mediated by CB1 cannabinoid receptors

Nature Medicine

17,

1228–1230

(2011)

doi:10.1038/nm.2435

Received: 09 November 2010
Accepted: 07 July 2011
Published online: 02 October 2011

:::::: Creato il : 16/10/2011 da Magarotto Roberto :::::: modificato il : 16/10/2011 da Magarotto Roberto ::::::