I'm very glad to hear that you're feeling a little better, Nick.

I think there is something to what you said. I was in a similar situation for awhile--sitting around in the dark just listening to audiobooks. And while to a certain extent I needed to do that because my sensitivites were so bad, once I started gradually adding more activities, I found that I was able to tolerate them if I give myself break periods. I also found that by lifting my mood, some of these activities actually helped me in managing my condition.

Like you said, I think the key is to be very attuned to one's early warning signals (fogginess, headache, whatever it is in your case), and to take breaks as soon as these symptoms start to show up. I'm trying to plan my time so that I'm not committed to any particular activity for more than, say, 2 hours at a time (at the most).

It's a very delicate balance. I've also had situations where I overdid it, even though I didn't notice it at the time, and ended up backsliding for weeks. I think with a lot of trial and error, we become better at identifying our limits. And I agree that it's probably a good idea to try to gradually reintroduce certain activities into one's lifestyle, starting (obviously) with the ones that are least stressful on one's brain.