I have a touch of what I call "Parkinson's brain". It's been acting up lately. I can't remember things! It's really frustrating. Losing my short-term memory was one of my first Parkinson's symptoms. It's worse on days when I'm tired, or when I'm stressed.
I've found this wonderful on-line brain trainer. I play it at least three times a day. I highly recommend it even if you don't have Parkinson's! it's called "Lumosity" and it's an app. You can get their iPad/iPhone version called "Brain Trainer". Check it out! www.lumosity.com.