Hi Sodalas, This is fascinating. I'd never heard of synaesthesia until I read your post. As far as I remember i've always seen letters, and words like the names of the months in color (for me, January is pink, February dark yellow, etc.), and I "see" the months of the year arranged as a sort of triangle, Jan. thru May on one side, June thru Aug. next, and Sept. to Dec., with Dec. 31st "touching" Jan. 1st. Stuff like that.
I now know this is considered a type of synaesthesia. Seems like everything gets labeled sooner or later. I thought by brain was just trying to organize information, and must have created this solution. I think everyone does this, to some degree, don't they?
I can see how it would be frustrating if you feel your thoughts are keeping you from normal daily functioning. A sudden increase in cognitive skills is often a result of increased physical activity (have you started playing soccer or something?) or a change in minerals in the brain.
Have your eating habits changed? Do you eat a lot of fish, or another source of omega-3 fatty acids?
That's so cool, the way you found a way to sleep.
You might talk to a nutritionist about how food affects the brain.
The brain is always learning, trying to process information, make sense out of everything. Too much information too fast sometimes makes me want to "run away" and bury myself in some mundane task, like folding laundry or other housework, till my thoughts calm down.
I would think it is likely for synaesthesia to intensify with time. As we mature and our bodies go thru physical and hormonal changes, our brains have to deal with a lot of changes and incoming stimulus in a relatively short span of time.
I have a sudden urge to go do some gardening. It reminded me that the brain "prunes" neurons that aren't used, or something like that. Maybe, if your brain doesn't prune neurons fast enough, you retain every bit of info you are exposed to. You don't forget anything.
Ahhhh. I'm thinking too much. Anyway, good luck to you.

Honeycomb