The story…
Why are we ticklish?
Learn language related to…
the body’s reactions
Need-to-know language
tickling sensation – tingling feeling on or under your skin
nerve endings – points on nerves that send messages to your brain
electrical signals – messages nerves send to the brain
defence mechanism – reaction from the body to protect itself from danger
Answer this…
Why isn’t being tickled always enjoyable?
Transcript
Professor Sukhi Shergill, Psychiatry and Systems Neuroscience, King’s College London
Tickling: love it, or hate it? Or even a bit of both… It’s a strange phenomenon.
There are two types of tickling sensation. Knismesis – a mildly annoying feeling caused by light movement like this. And there’s gargalesis – which is caused by a deeper pressure on your skin.
When your skin is touched, the nerve endings underneath send electrical signals to the brain. We laugh when we’re tickled because the sensation is picked up in two areas of the brain at once – the part which analyses touch, but also the part that creates pleasure.
But of course, being tickled isn’t always enjoyable.
In fact, it also affects the part of the brain that makes you feel panic in the face of danger.
So, strange as it may seem, laughing when you’re tickled could be a sort of primitive defence mechanism – giving a signal to show our submission to a predator.
So, why can’t we tickle ourselves? We think it’s to do with the brain’s cerebellum that monitors our movement. It can tell the difference between expected and unexpected sensations. In other words, it already knows what you’re doing and is too clever to react.
Did you get it?
Why isn’t being tickled always enjoyable?
Because it affects two parts of the brain, including one that makes us feel panic.