Scientists discover why you can't tickle yourself
Oh gee, probably after spending millions of dollars of confiscated tax money, the pointy-heads reached the conclusion that being tickled has a lot to do with anticipation.
*sigh* This is Govco science at its finest. Hell, as an amateur physiological experimenter and inveterate, sadistic, unrepentant tickler of hapless women and children, I could have told them that it's all about the anticipation, and saved them their likely ridiculous budget allocation! If you want to increase the power of a tickle, increasing the anticipation has a very large influence on the perceived sensation, often almost as much as varying the type and location of the physical stimulus itself.