Brain Teaser

The other day I was talking to my kids about cough suppressants and explaining that they work by affecting a part of your brain, instead of affecting your throat, when you get that little tickle. In the medula of the brain there is a "cough center" that the antitussive works on to suppress the cough.
So after explaining this to them, Josh asks me, "I can cough on purpose, does that mean I can tickle my brain?"
That is quite possibly the funniest thing he's ever asked me.