[4] His research has found that "the promise of treatment activates areas of the brain involved in weighing the significance of events and the seriousness of threats.
In this study, the subjects who received morphine and then a placebo endured significantly more pain than did patients in any of the control groups.
[6][7] In a 2011 paper, Benedetti and co-authors argued that there exist many different placebo effects, "with different mechanisms and in different diseases, systems, and therapeutic interventions.
"[8] He has also published research on the nocebo effect, in which adverse events are produced as a result of negative expectations.
[9][10][11] Another of Benedetti's studies found that when individuals were told about a possible link between high altitudes and headaches before going on a high-altitude hike in the Italian Alps, it led to an enhancement of the cyclooxygenase-prostaglandin pathway in those individuals, and that they developed significantly more headaches than the control group did.