reversible brain damage

Recently I learned that I like reading graduate-level mathematical physics textbooks, and they're better with loud classical music in the background. So far I recognize lots of equations and things, but trying to do the problems at the end of the first chapter feels like touch typing on a keyboard where someone has moved only some of the keys. I'll be chugging along ok until I can't remember something really basic and have to move on to something else, and then two hours later I'll be chatting with the really, really sick lady, and she'll get to hear about it when the missing equation pops into my head. (She, like many people, really has no use for stray physics equations, but she's very nice about it.)

I had to start with math books because I tried starting on a signal processing book so riddled with errors that I spent all my time re-deriving things and then doubting my results, even though they at least had the right coefficients in them, as opposed to the ones in the book. (Note to Ashfaq A. Khan -- you had an editor, but you needed a nerdy editor who would call it when you used N and K interchangeably or had a's where you should have had b's, or had nothing at all. I'd help, but I understand no one budgets for nerdy editors.)

So it's been like learning to walk after five years of broken legs, and this person who's stumbling around appears to like playing the fiddle (also stumblingly), and classical music. I attribute this improvement in my health to two things: some new supplements, and something a friend passed along ("God doesn't want us to be sick"), which helped me let some things go, and the less anxious you are, the better you feel. The only downside here is that now I feel like I woke up with some amnesia after five years of some nice-enough imposter (also me) holding down the fort, and it's kind of upsetting.