Thinking out loud...

Some aspects of PD are a common element amongst ourselves and even with "normal" folks. The damage to the SN is an example. The conventional wisdom is that we all have it. The CW also is that a normal who develops such damage will develop PD.

Some aspects are a common element with other conditions. There is an element of neuropathy, for example, that we share with diabetics. This neuropathy and other problems worsen with time, as does the movement element. So PD is an ongoing process. It doesn't seem to stop.

When does it begin? There are reports of children with PD. Polls on this forum have shown that half of us remember constipation - a PD related factor - as being a big deal in our childhood.

Our reaction to stress, however, is near unique. Is there any other disease where the simplest of stressors quickly renders one helpless? If this response is indeed unique, isn't it sensible to think there may be a key there?