Have you ever suddenly found yourself doing something that you didn't even have any intention of doing with no memory of the moments beforehand?
Couple of years ago I was on my computer just reading DiS or something as per usual at about three in the morning and then suddenly I was in the shower. No recollection of walking to the bathroom, getting undressed or even making the decision to do so. I'd never have a shower at that time and wake people up. I had no desire to have a shower.