Brian, I'd like to hear more about your last sentence, "You may not suffer any noticeable effects, but this may be because you are on the 'learner slopes' of PD, and damage may still be occuring, and will show up in later stages of PD." In particular, I'd like to hear a description of the 'learner slope' and where someone might go from there and the second item is regarding the 'damage'. Are we refering to our old friend the free radical? Terry Brennan