Heh, me too :(
just recently i've been posting here trying to help people, and now I became one of them.
To set things straight - this is not depersonalization. I remember how dr/dp feels like, but this is different. It feels as though I became dumber, I lose track of words that I read. I also have troubles going to sleep.
This is how I explain this. Personally in my case, it might've been caused by stress. I'm a graduating senior (getting done this june). Over the few last semesters, i've had to work harder than anybody else, partly because I don't enjoy studying but still have to get good grades, and partly because I mismanaged my curriculum plan earlier. At the end of the previous semester, I ended up having to study and understand an entire book of advanced math, in order for me to pass the class. I haven't slept for days, and was in constant fear of failing the class.
The class is over now, I didn't fail it. But I think the prolonged stress finally got me, and I snapped.
I quit smoking. I quit eating junk. I'm planning to start exercising regularly once i'm through college, which is soon.
This "foggy brain" condition is weird, and it used to cause severe panic attacks in me. Not anymore. I'm kinda used to it now, basically I feel like I didn't sleep for one night.
If you people figure out what it is, let us all know. Also, the guy who decided to fix the condition with regular exercise - keep us posted. Back in the day I used to lift weights, and it helped a lot my mental and emotional wellbeing. Now unfortunately, the circumstances keep me from taking good care of me, so i'm coping temporarily.