I ran across some interesting reading this afternoon. Apologies to our senior members for any redundancies...

Interesting anecdotes about the failed efficacy of Levodopa in clinical trials. Apparently, the clinical trials did not meet outcomes due to placebo effect (much like Ceregene) back in the 60's when the drug was first introduced. Yet, today it is our gold standard. An interesting history on clinical trials of levodopa and the problems of motor fluctuations...Clinical Trials in Neurology. Roberto J. Guiloff. 2001.

The Power of Mind and the Promise of Placebo. World Research Foundation

Why Parkinson's drug trials should abandon Placebo...

Brain Mechanisms Underlying the Placebo Effect in Neurological Disorders.
Functional Neurology. Cavenna, et al. 2007

Expectation and Dopamine Release: Mechanism of the Placebo Effect in Parkinson's Disease. Science. Fuente-Fernandez, et al. 2001

Researchers found that the placebo provided benefits comparable to a therapeutic dose of levodopa. PET scans substantiated the results.