There are a number of likely causes of Parkinson's disease. In our last
daily update we discussed that some brain cells die because they cannot
get rid of the poisons that build up within them. The mechanisms that
are responsible for removing waste products and toxins break down.
Another likely cause of PD is excitotoxicity.

The first half of the word excito indeed mean excite. The second half,
toxicity, mean poisoned to death. Cells that get overstimulated or
overexcited can burn themselves out and die.

Researchers suspect that an abundant brain chemical glutimate,
contributes to this overstimulation. Glutimate stimulates neurons. If
there is too much glutimate, cells can wear out too quickly. It would
be like asking a marathon runner to sprint through the race. They would
not last very long at such a brisk pace.