If you thought the placebo effect was all in the mind, think again. Scientists have solved the mystery of why some people benefit from remedies that do not contain any active pain-relief ingredients. Research suggests that placebos work, in part, by blocking pain signals in the spinal cord from arriving at the brain in the first place.
When patients expect a treatment to be effective the brain area responsible for pain control is activated, causing the release of natural endorphins. The endorphins send a cascade of instructions down to the spinal cord to suppress incoming pain signals and patients feel better whether or not the treatment had any direct effect.
The sequence of events in the brain closely mirrors the way opioid drugs, such as morphine, work — adding weight to the view that the placebo effect is grounded in physiology.
The finding strengthens the argument that many established medical treatments derive part of their effectiveness from the patients’ expectation that the drugs will make them better.