Pain And Perception

I read an interesting article in BBC News Health a couple of weeks ago. It reviewed 2 recent studies on pain. The first was published in The Journal of Pain by Atsuo Yoshino et al. Subjects were shocked with an electric current whilst they were shown pictures of sad, happy or neutral faces. Photos of an emotional face usually provoke the same emotional response in the person viewing the picture. Although the electrical stimulation was the same in all cases, subjects felt more pain when looking at sad faces.

The second study was conducted by Marion Hofle et al. in Pain. The researchers asked the subjects to place one of their hands under a screen. On the screen, they played a video of a hand being pricked by a needle, poked by a cotton bud or just left alone. The subjects perceived the hand on the screen as their own.  A painful or non-painful stimuli was applied simultaneously to the video. Viewing the needle prick increased the unpleasantness ratings of the stimulus.

As these studies have shown, negative emotional states and negative expectation seem to increase pain and so the mind plays an important role in the experience of pain. As a physiotherapist, dealing with pain is a daily occurrence and I can remember qualifying as an acupuncturist over 10 years ago…I was desperately keen to use my new skill on anyone that was willing to try and worked hard at convincing anyone that was hesitant to try! With those that were initially hesistant…possibly due to a slight needle aversion, I quickly noticed their exaggerated responses to acupuncture. I can remember several occasions when I would gently touch them with a finger or with the plastic guide tube that surrounds the needle and they would jump and shout “ouch”…to which I would reply “relax, we haven’t started yet!” I’ve now learnt from those experiences and no longer feel the need to convince everyone to have acupuncture…no matter how great I think it is!

John Milton was right in Paradise Lost…“The mind is its own place, and in itself can make a heaven of hell, a hell of heaven.”