Sticks and stones may break my bones, and the words my clinician uses can also hurt me. Sounds crazy, but it’s not. Whether you’re into pain science or not, we’re all probably familiar with the placebo effect to some extent. We’ve all heard stories about someone receiving a sham treatment and getting the same benefit as the actual treatment, like acupuncture for example(1). What I find really fascinating is that the placebo response isn’t some mystical phenomenon, we can explain why it’s happening. We’ve all heard of morphine as an extremely potent pain killer. Did you know our bodies are capable of producing our own version of morphine? They’re called beta-endorphins, an endogenous opioid, and they’re actually up to 33 times as potent(2). So we’re actually able to control for a placebo effect by giving the opioid-antagonist Naloxone, which binds the receptors β-endorphins normally hook up with, blocking analgesic effects(3).
What is less talked about is the nocebo effect, often called placebo’s evil twin. Instead of symptoms resolving, we see symptoms either being prolonged or possibly getting worse. Not as much is known about about the placebo, though it’s suggested there are both psychological and neurophysiological roles, including endogenous opioids, cholecystokinin, and dopamine(4). Here’s a diagram for those a bit more interested in the physiology.
Now think about somebody who’s got a bit of low back pain and they go and see the chiropractor or physical therapist, whose opinion is held in the highest regard by the patient(7). This doctor tells them the reason their back is hurting is because their spine is out of alignment. It must have just slipped out when they went to tie their shoe. What kind of message does that send to this person? They’re going to be fearful every time they go to bend. “You want me to lift that box? My back went out trying to tie my shoes. No way I’m bending to lift anything from the floor anymore.”
Consider that pain isn’t created in the tissues, and it’s better understood as a circuit of neurons in the brain firing collectively to produce the experience of pain. Our thoughts, beliefs, emotions, and knowledge are all capable of turning the pain circuit on, even in the absence of tissue damage or nociception(5). It’s for this reason that anybody working with someone in pain needs to be selective about the words they use. If we can change someone’s beliefs regarding their bodies, that they’re not fragile and easily injured, then we can potentially change their pain experience.
“The single most effective pain reliever is self-efficacy (the sense that one can manage and that everything will be okay).” — (8)
- Colquhoun D, Novella SP. Acupuncture is theatrical placebo. Anesth Analg. 2013;116(6):1360–3.
- H. H. Loh, L. F. Tseng, E. Wei, and C. Hao Li, “β-endorphin is a potent analgesic agent,” Proceedings of the National Academy of Sciences of the United States of America, vol. 73, no. 8, pp. 2895–2898, 1976.
- Benedetti, F. (2005). Neurobiological Mechanisms of the Placebo Effect. Journal of Neuroscience, 25(45), 10390–10402. doi:10.1523/jneurosci.3458–05.2005
- Planès S, Villier C, Mallaret M. The nocebo effect of drugs. Pharmacol Res Perspect. 2016;4(2):e00208.
- De felice M, Ossipov MH. Cortical and subcortical modulation of pain. Pain Manag. 2016;6(2):111–20.
- Puentedura EJ, Louw A. A neuroscience approach to managing athletes with low back pain. Phys Ther Sport. 2012;13(3):123–33.
- Darlow B, Dowell A, Baxter GD, Mathieson F, Perry M, Dean S. The enduring impact of what clinicians say to people with low back pain. Ann Fam Med. 2013;11(6):527–34.
- Menendez ME, Ring D. Factors Associated with Greater Pain Intensity. Hand Clin. 2016;32(1):27–31.