Researchers from the University College London suggest that you would experience less pain if you look at the area where you are being treated

They found that the participants were able to bear 3 more degrees of heat if they were directly looking at the point where the probe was being applied while the threshold increased further when the arm was made to appear bigger using mirrors.
“You always advise children not to look when they are having an injection or a blood sample taken, but we have found that looking at the body is analgesic - just looking at the body reduces pain levels”, lead researcher Prof Patrick Haggard wrote in the study which was published in the journal Psychological Science.
Source-Medindia