My mother has Parkinson's, and she does not know me. But she always is glad to meet me, as a first encounter as it were, that I am one of her sons, until she forgets yet again, 30 seconds later, that I had some signficance in her life. She has no memory of my father, but sometimes remembers her parents, for a moment or two. She still has a very good vocabulary, which she uses effectively. The mind is a complex instrument. Some things go, and some don't.
Awful. Sounds like she may also be suffering from Alzheimer's as well. Supposedly there is no way to definitively diagnose it until after the patient has died via autopsy. My grandmother died from its effects back in 2001 at 92 (though she didn't rapidly go downhill until after my Aunt and Uncle were forced to remove her from her home a few years beforehand -- it was too dangerous to have her live in that crime-ridden neighborhood in Albuquerque, but my Aunt stuck her in different retirement homes, rather than bring her in (she was actually kicked out of more than 1 because she was very difficult to deal with) -- she couldn't deal with the situation well, and kept threatening my parents with packing her off to us in Nashville). Ah, well... Hopefully in the near future we'll find a cure to these dreadful ailments.
My Dad died last year worn out and totally tired of his Parkinson's. His mind and wit was clear and sharp to the end; his brain's chemistry lab failed him. He was an OB/GYN by profession and missed the symptoms. Just after he retired (18 yrs+/-) a friend of his(businessman) who was diagnosed told him he had Parkinson's. Dad went to a neurologist and was diagnosed. He fought the loss of mobility with a vengance. He loved to play golf; when we finally had to deny him to drive a car was bad. He continued to play although his game was just slapping a ball around the course. He was still walking. He finally hit the wall despite sinemet et al March of 04 and was in his words "doomed" (wheel chair/bed bound). He read all the articles and we discussed options. He never thought that fetal cells should be the point of research. He passed away Mar. 05, just worn out, his mind still sharp. He was so tired of his condition once he couldn't walk; losing driving was bad, not being able to play golf(a shadow of his former game) was devastating, bedridden...
Terrible disease as all neuromusculoskelatal diseases are.
My prayers are with you.