Dopamine is an organic chemical produced by a healthy brain. It is a neurotransmitter--a chemical released by neurons (or nerve cells) to send signals to other nerve cells. There are several pathways dopamine travels. One of the pathways is directly connected to the component of reward-motivated behavior. The anticipation of any type of reward increases the level of dopamine in the brain, often causing a euphoric response.
The other pathways dopamine uses are involved in motor control and the release of various hormones. The latter pathways are of course, why Parkinson's sufferers (whose brains produce far less of the chemical) have trouble with movement, elimination control, body temperature and a myriad of other bodily functions.
In order to obtain informational research for any neurological disease, blind studies are conducted. Because PD patients are dopamine-deprived, their research data becomes skewed. For instance, if a PD test subject believes he has been given a placebo, his dopamine levels may drop because he is saddened or anticipating a negative outcome (placebo effect). Or, if the subject believes he has been given life-saving medication, his diminished dopamine levels might climb (noncebo effect). Because Parkinson's is a dopamine-based disease, results can be easily misunderstood. Parkinson's is the only disease, Neuro or otherwise, to experience these issues in trials. To say testing is a challenge is a vast understatement.
PD researchers have had to take another tact to finding a cure. One of the avenues they are investigating is the question of why a PD tremor stops when the patient is in REM sleep. All tremor stops during deep sleep mode and they are still unsure why. If scientists can find an answer to that question, they might well be on their way to finding a cure, or at the very least, a possible solution to essential tremor. So, be assured researchers are working diligently even when we don't feel like they're moving fast enough.
Parkinson's is a unique and puzzling disease, and the challenges are enormous. But, as we wait for progress we can pray, give financially, and/or participate in a study. All of these things add to the arsenal of data for a Parkinson's cure!
