I've also noticed that my skill seems to be deteriorating a bit. I worry that I may have f'd my attention span. So I decided to run an experiment and see how high I can count in my head. Not out loud. Just count until you lose the thread as some other thought barges in.
I find that I only seem able to get to the low thousands.
I also find that I'm tired all the time. This condition seems to have developed slowly over the past year or so. I don't know when exactly and I have yet to find a doctor who can tell me why.
So I guess my question to you is, how high can you count in your head?