Which people are more susceptible to the placebo effect?

 Religious people are more likely to benefit from placebo drugs or drugs that promise spiritual and supernatural healing. Recently published research has shown that placebos can trigger significant brain responses, as well as positive experiences associated with religious beliefs.

The placebo effect has been used in medicine for centuries. How does it work? There are many different types of placebos with different effects on health parameters. In order for a placebo to be valid, several conditions must be met. The patient must believe that they have received the real drug. Many psychological mechanisms are associated with placebo responses. Increased hope, positive expectations, and decreased anxiety can change the attitudes that control the patient's response to treatment.

This study examined the placebo effect in the context of religious beliefs and practices. Participants were given a harmless substance (tap water) along with a verbal suggestion that the water would come from the sanctuary of Lourdes (a Catholic pilgrimage site with reports of miraculous healings). In the placebo study, 37 women participated who believed that water from the sanctuary of Lourdes had a positive effect on their spiritual, emotional and physical state. In one group, participants drank tap water labelled “Lourdes water” (placebo). In another (control) session, they received tap water labelled “tap water”. Participants rated their physical state during the experiment and were asked about specific thoughts, feelings and bodily sensations immediately after each of the two treatments. The placebo reduced rsFC (brain activity in the resting state or in the off-task state) in the frontal and parietal cognitive control networks and increased rsFC in the attention network (insular cerebellar connection). During the sessions, participants rated their emotional state as very pleasant and calm. Immediately after the session, participants reported an increase in the intensity of pleasant bodily sensations and positive emotions (e.g. gratitude) after drinking the Lourdes water. These results provide the first evidence that placebo, in the context of religious beliefs and practices, can alter emotional state and induce real changes in the cognitive control structure of the brain.