Short answer: Your brain knows you are about to be tickled when you do it yourself. This cancels out the normal tickling response.
Have you ever tried to tickle yourself? Go ahead and try it. It doesn’t work. Why is that? In order to understand that, we first need to understand what tickling is.
According to neuroscientists at the University of London, there are two parts of the brain responsible for how tickling is processed. These regions work together to trigger the tickling response when someone is tickling you.
But, why do we laugh when tickling isn’t always a pleasurable feeling? According to a 2013 study by researchers from Eberhard Karls University, this happens because a joke and a tickle both trigger the same part of your brain. Our ancestors might have submitted to aggression by laughing. It’s likely that our brain is processing being tickled as a threat. Hence, the tickling response.
So, why can’t we tickle ourselves? It appears to come down to our cerebellum (part of the brain) being able to predict it, therefore, canceling the effect out.
In other words, your cerebellum knows your hand is going to try and tickle you. Because of this, the sensation doesn’t take effect. It’s no longer a surprise, so the brain processes it differently.
If you spend a lot of time alone but really love being tickled, you can always get a tickling robot. 🙂
Have you ever tried tickling yourself?