(Picture from Brain & Mind, a Brazilian journal on neuroscience.)
The German experiment consisted of giving subjects two “treatments” to prevent pain, one said to be a lidocaine cream and the other a control. Those given what they believed to be lidocaine experienced less pain, but in fact both creams were identical.
This means the “placebo effect” is real. It causes distinct physiological changes that can be measured.
The mind is still very much involved. Those who believed a treatment would work showed a much greater placebo effect than those who did not believe or were unsure.
The research does more than validate possible new treatments. It also illustrates how many sham treatments, in the present and the past, could provide real relief to patients, by triggering this physiological effect.
There is a second implication in all this, the nocebo effect. Whether doctors expect something to work or not telling the patient it definitely will work can impact the result. Telling someone an experimental treatment may not work may reduce its chances of providing relief.