The placebo effect: how the subconscious fits in

Perspect Biol Med. 2012 Winter;55(1):43-58. doi: 10.1353/pbm.2012.0005.


The placebo effect is very well known, being replicated in many scientific studies. At the same time, its exact mechanisms still remain unknown. Quite a few hypothetical explanations for the placebo effect have been suggested, including faith, belief, hope, classical conditioning, conscious/subconscious expectation, endorphins, and the meaning response. This article argues that all these explanations may boil down to autosuggestion, in the sense of "communication with the subconscious." An important implication of this is that the placebo effect can in principle be used effectively without the placebo itself, through a direct use of autosuggestion. The benefits of such a strategy are clear: fewer side effects from medications, huge cost savings, no deception of patients, relief of burden on the physician's time, and healing in domains where medication or other therapies are problematic.

MeSH terms

  • Autosuggestion
  • Conditioning, Classical
  • Endorphins / physiology
  • Humans
  • Mind-Body Relations, Metaphysical
  • Pain / drug therapy
  • Pain / psychology
  • Placebo Effect*
  • Placebos / therapeutic use*
  • Unconscious, Psychology*


  • Endorphins
  • Placebos