Understanding the Placebo Effect: Contributions from Neuroimaging

@article{Lidstone2007UnderstandingTP,
  title={Understanding the Placebo Effect: Contributions from Neuroimaging},
  author={Sarah C. Lidstone and A. Jon Stoessl},
  journal={Molecular Imaging and Biology},
  year={2007},
  volume={9},
  pages={176-185}
}
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… 
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References

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Understanding the Placebo Effect: Contributions from Neuroimaging
TLDR
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 Placebo Response as a Reward Mechanism
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TLDR
The results indicate that caffeine expectation induces dopaminergic placebo effects, and that these effects are similar to previous findings with oral caffeine, and suggest that caffeine and placebo caffeine may share some dopamine mechanisms of action.
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TLDR
fMRI experiments found that placebo analgesia was related to decreased brain activity in pain-sensitive brain regions, including the thalamus, insula, and anterior cingulate cortex, and was associated with increased activity during anticipation of pain in the prefrontal cortex, providing evidence that placebos alter the experience of pain.
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TLDR
In vivo evidence is provided for substantial release of endogenous dopamine in the striatum of PD patients in response to placebo, indicating that the placebo effect in PD is powerful and is mediated through activation of the damaged nigrostriatal dopamine system.
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TLDR
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TLDR
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