Scientist discovers why we can't tickle ourselves Original text: from here: http://www.ananova.com/news/story/sm_57566.html A scientist has revealed why it is impossible for people to tickle themseleves. Sarah-Jayne Blakemore, from University College London, placed volunteers in a brain scan. They attempted to stimulate themselves with a plastic tickling device, but it had no effect. They only felt anything when Ms Blakemore did the tickling. The scans showed that feeling tickled coincided with activity in the somata sensory cortex area of the brain, which perceives touch, and the anterior cingulate, which acts as a pleasure centre. But when volunteers tried to tickle themselves, another brain area, the cerebellum, switched in to dampen down the experience. The cerebellum told the other brain areas to "stand down" because the sensation was self-induced. Ms Blakemore revealed her findings at the British Association Festival of Science at Imperial College, London. She said: "The results showed that when tickling themselves, the areas of the brain that process touch and pleasant sensations were less active than when they were tickled by the experimenter, in this case me." She said people with schizophrenia seemed to lack the ability to distinguish between self-induced and external stimulation. This was thought to account for some of the hallucinations and delusions they suffered. It was possible that schizophrenics might be able to tickle themselves, she said. Last updated: 18:28 Sunday 10th September 2000.