You probably know of certain places on your body where you are more ticklish than others. But if you’ve ever tried to tickle yourself -- even in your very most ticklish spots -- you’ve probably noticed that it doesn’t work!
A tickle is your body’s reaction to a person or thing that is touching it, the feeling of which makes you laugh or squirm or flinch! Most scientists believe that the reason you can’t tickle yourself has to do with the element of surprise that seems to be so important to ticklish reactions. – Your brain keeps track of what your body is doing at all times. So, for example, when you raise your arm into the air, your brain takes note that your arm is now in the air.
If decide to try and tickle yourself, your body will not be surprised to receive the ticklish touch because your brain has already sent out a message that you are moving in on making a tickle! However, the touch of something you aren’t expecting (like a friend with tickly intentions or the brush of a feather) is much more likely to result in a batch of the giggles!