Because this is basically bullshit. The title calls it neuroscience, but they're studying classical stimulus-response, just like Wundt. Then they come up with a

Because this is basically bullshit. The title calls it neuroscience, but they're studying classical stimulus-response, just like Wundt. Then they come up with a theory that needlessly incorporates some neuro-stuff, which then is pronounced fact. If they would have done it properly, they would have noticed that you can tickle yourself. I'm pretty ticklish, and like you, I can also tickle myself under my own feet.