I'm very ticklish, so why can't I tickle myself

asks sander:
A. The panicky feeling we get when we are tickled is a natural reaction which has evolved as a defence against creepy crawlies and bugs. Tickling makes us goose-pimply and sends us into a state of panic - or uncontrollable laughter .

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Q. Why does it still happen even if we know we're being tickled and not overrun by spiders
A. You tend to be the most panicky and the most ticklish when you are not expecting to be tickled, but even when you know it's coming, the feeling of unease will cause you laugh. If you are especially ticklish, you might even begin laughing before some touches you.

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Q. So why can't we tickle ourselves
A. Researchers looked at the brains of people trying to tickle themselves and discovered that you can't trick yourself into being tickled. One explanation is that the brain can cope with things it expects to happen, and simply ignores them. For example, we aren't aware of the soles of our feet when we walk, or of the pressure on our fingertips when we type. And so, if we try to tickle under our arms, the brain knows what's coming and gets itself ready for it. Because there's no sense of unease or cause for panic, we don't respond in the same way.

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The part of the brain that monitors our movements and can tell the difference between expected sensations and unexpected ones is called the cerebellum. It recongises the pressure on the soles of your feet as an expected sensation, but if you stub your toe on the end of your bed, it would see it as an unexpected�sensation.

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Q. So there's no way we can tickle ourselves
A. Well, scientists have developed a robot which lets people tickle themselves. You lie on your back with your eyes closed and the robot nearby. The robot has plastic rod covered with foam and is controlled by a remote control joystick. When you activate the rod, the robot reacts after a short delay. Even with delays as short as a fifth of a second it has been described as being the same as having someone else tickle you.

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By Sheena Miller