Being tickled? A mental or physical reaction? or both?

I read an article that said tickling a toddler is torture rather than pleasure . Even though they laugh . (laughter is a vibration of the esophagus) . It's interesting about mental reaction. I got surgery, and about 16 staples. When the Dr. started to remove the staples it felt ok, but as he progressed it started to burn and hurt .I asked him about that and he said that if he started from the bottom and worked his way up that the same thing would happen .He said it was because my brain interfered . That happened to me once when I got bit by a dog. It didn't hurt until I looked at the wound . So in the case of tickling, I think it starts out physical and ends up mental . And can turn to anger .