Neurobiology of placebo effect in Parkinson's disease: What we have learned and where we are going

@article{Quattrone2018NeurobiologyOP,
  title={Neurobiology of placebo effect in Parkinson's disease: What we have learned and where we are going},
  author={Aldo Quattrone and Gaetano Barbagallo and Antonio Cerasa and A. Jon Stoessl},
  journal={Movement Disorders},
  year={2018},
  volume={33}
}
The placebo effect is a phenomenon produced when an inert substance administered like a regular treatment improves the clinical outcome. Parkinson's disease (PD) is one of the main clinical disorders for which the placebo response rates are high. The first evidence of the neurobiological mechanisms underlying the placebo effect in PD stems from 2001, when de la Fuente‐Fernandez and colleagues demonstrated that a placebo injection led to the release of dopamine in the striatal nuclei of PD… 
Placebo responses in Parkinson's disease.
  • J. Lou
  • Psychology, Medicine
    International review of neurobiology
  • 2020
What is the role of placebo in neurotherapeutics?
TLDR
The biological mechanisms and the clinical implications of placebo effects with particular emphasis on neurology and psychiatry, for example in pain, movement disorders, depression, are described.
Maximizing placebo response in neurological clinical practice.
Psycho-Neuro-Endocrine-Immunological Basis of the Placebo Effect: Potential Applications beyond Pain Therapy
TLDR
This review integrates current knowledge about the psycho-neuro-endocrine-immune basis of the placebo effect and its possible clinical applications and suggests a relationship between the placebo response and the opioid, cannabinoid, and monoaminergic systems.
Molecular Mechanisms and Therapeutic Strategies for Levodopa-Induced Dyskinesia in Parkinson’s Disease: A Perspective Through Preclinical and Clinical Evidence
TLDR
The present study is focused on discussing the recent updates in molecular mechanisms and therapeutic approaches for the effective management of LID in PD patients.
Cerebral differences between dopamine-resistant and dopamine-responsive Parkinson's tremor.
TLDR
The hypothesis that dopamine-resistant resting tremor may be explained by increased contributions of non-dopaminergic brain regions, such as the cerebellum, is tested and suggests that this region is less susceptible to the inhibitory effects of dopamine.
Expectations of Benefit in a Trial of a Candidate Disease‐Modifying Treatment for Parkinson Disease
TLDR
How well study participants understand the concept of slowing disease progression and how their expectations of benefit are shaped in related clinical trials is not well known.
Expectancy and affective response to challenging balance practice conditions in individuals with Parkinson’s disease
TLDR
Regression analyses revealed that self‐efficacy increase from initial practice predicted performance at the end of practice and at retention, highlighting the potential contribution of psychological factors on motor function and rehabilitation in individuals with PD.
...
...

References

SHOWING 1-10 OF 73 REFERENCES
How Placebos Change the Patient's Brain
TLDR
Data indicate that different social stimuli, such as words and rituals of the therapeutic act, may change the chemistry and circuitry of the patient's brain, which suggests a cognitive/affective interference with drug action.
Effects of expectation on placebo-induced dopamine release in Parkinson disease.
TLDR
The strength of belief of improvement can directly modulate dopamine release in patients with PD and the importance of uncertainty and/or salience over and above a patient's prior treatment response in regulating the placebo effect is demonstrated.
The placebo treatments in neurosciences
TLDR
Dopaminergic pathways mediating reward may underlie PL-mediated improvement in Parkinson disease and diseases lacking major “top-down” or cortically based regulation may be less prone to PL-related improvement.
Expectation and Dopamine Release: Mechanism of the Placebo Effect in Parkinson's Disease
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.
Molecular Mechanisms of Placebo Responses In Humans
TLDR
The formation of biological placebo effects is now being linked to the concept of resiliency mechanisms, partially determined by genetic factors, and uncovered by the cognitive emotional integration of the expectations created by the therapeutic environment and its maintenance through learning mechanisms.
Placebo effect of medication cost in Parkinson disease
TLDR
Examining the effect of cost, a traditionally “inactive” trait of intervention, as contributor to the response to therapeutic interventions provides Class III evidence that perception of cost is capable of influencing motor function and brain activation in Parkinson disease.
Immediate Placebo Effect in Parkinson’s Disease – Is the Subjective Relief Accompanied by Objective Improvement?
TLDR
The results suggest that placebo interventions in PD may have an immediate subjective sensation of improvement but result in no significant objective motor changes compared with levodopa treatment.
Another face of placebo: The lessebo effect in Parkinson disease
TLDR
This study shows that the use of a placebo can be associated with a clinically significant reduction in the magnitude of change of the mUPDRS after an active treatment in RCTs for PD.
The placebo-reward hypothesis: dopamine and the placebo effect.
...
...