Molecular Imaging and Biology

, Volume 9, Issue 4, pp 176–185 | Cite as

Understanding the Placebo Effect: Contributions from Neuroimaging

Review Article

Abstract

Neuroimaging studies have provided a major contribution to our understanding of the mechanisms of the placebo effect in neurological and psychiatric disorders. Expectation of symptom improvement has long been believed to play a critical role in the placebo effect, and is associated with increased endogenous striatal dopamine release in Parkinson’s disease and increased endogenous opioid transmission in placebo analgesia. Evidence from positron emission tomography and functional magnetic resonance imaging studies suggests that expectations of symptom improvement are driven by frontal cortical areas, particularly the dorsolateral prefrontal, orbitofrontal, and anterior cingulate cortices. The ventral striatum is involved in the expectation of rewarding stimuli and, together with the prefrontal cortex, has also been shown to play an important role in the placebo-induced expectation of therapeutic benefit. Understanding the mechanisms of the placebo effect has important implications for treatment of several medical conditions, including depression, pain, and Parkinson’s disease.

Key words

Placebo effect Positron emission tomography Parkinson’s disease Dopamine Reward Expectation Depression Pain 

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Copyright information

© Academy of Molecular Imaging 2007

Authors and Affiliations

  • Sarah C. Christine Lidstone
    • 1
  • A. Jon Stoessl
    • 2
  1. 1.Pacific Parkinson’s Research Centre and Graduate Program in NeuroscienceUniversity of British ColumbiaVancouverCanada
  2. 2.Pacific Parkinson’s Research CentreUniversity of British ColumbiaVancouverCanada

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