It might be your breathing. Stand up, breathe deep and get a bit of oxygenated blood flowing to your brain. Go up and down a few flights of stairs if you can.

It might be your breathing. Stand up, breathe deep and get a bit of oxygenated blood flowing to your brain. Go up and down a few flights of stairs if you can. I find if I focus for an hour or so my breathing gets shallow and it was pushing my blood pressure up, and giving me brain fog. A quick bit if exercise (chores work for me because I work from home) fixes it up