"could be." It could also be _completely normal_ losing one's ability over time by not practicing, and one could get it back by just... doing more practice. I'

"could be." It could also be _completely normal_ losing one's ability over time by not practicing, and one could get it back by just... doing more practice. I'm in my mid-20's and I can't do mental math as well as I used to. Why? I don't spend as much time on it now, as I did when I was in school some years ago.