Whenever I get new software, or a new book that I'm really interested in (the last one I got was http://www.edwardtufte.com/tufte/books_be "Beautiful Evidence" by Edward Tufte), I start reading and in about one half hour I get really really tired and fall asleep. This seems to happen everytime. When I wake up I remember everything I read, and even if I misunderstood it, it's like it's locked in my mind forever--because if I DID misunderstand it, I have problems not remembering it incorrectly from that point on.
The most recent software I bought was an upgrade from Photoshop 7.0 to Photoshop CS3 Extended. Everytime I start to experiment with the new stuff, I get really exhausted.
I wonder if this happens to anyone else; is this phenomonon known or studied, I wonder.