Have you ever wondered why you can’t tickle yourself? The scientific explanation...

Some people are more ticklish than others – but it’s almost impossible to tickle yourself...  

Paul Bays of the Institute of Neurology at University College in London says that’s because the brain is constantly predicting what is about to happen. Our reaction to being tickled is actually a defense mechanism that works as a “non-self” detector. The tickle reflex requires a certain amount of surprise. When self-touch is expected, we don’t feel threatened and the reaction is not activated. 

Even if you know you’re about to be tickled by someone or something else – the element of surprise is still there. You can’t predict the exact timing or intensity of the oncoming tickle – and that anticipation can actually intensify the ultimate reflex.