Thomas Shey
Legend
I'm 60 and don't see any decline. I'm still able to learn, understand and play new games regularly. Some people can't integrate new rule sets at my age. The brain is a muscle; keep exercising it, and all should be fine. (Let's not talk about the dreaded disease we should not name lest it manifests.)
I seem to have lost some of my multitasking capability (I'm now 68), but some other elements are hard to tease out: I've always had cruddy memory (as in, back when I was 15) so has it gotten worse? Sometimes I lose focus, but is it a standalone problem, or just a side effect of not having all the energy I once did?
It can be really hard to say.