I had this for 8 months 24hrs 7days a week when I didn't know that I had AF.
This is the hell of brainfog yes. You live in a depersonalized - uber light sensitive - dream like state. If you turn you'r head you mis a couple of 'frames' from what you are seeing. Half awake, half dreaming.. very very low internal energy to feed the neural parts.
This I hated the most, I got rid of it in less than 2/3 months by quiting everything and do the budwig diet, but that helped for me personally.. I didn't know I had AF yet then. But this turned on the very little energy flows to my brain or something to slowly get rid of this fog hell.
I don't use [extra, only foods en some chlorella] vitamin C at all it does nothing special for me, strange huh.. and I'm healing ;-)