Placebo Effects in the Context of Religious Beliefs and Practices: A Resting-State Functional Connectivity Study
Placebos (inert substances or procedures) can have a positive impact on a person's psychological and physical well-being, involving specific changes in brain activity. There are many different types of placebos that have different effects on health-related variables. This study examined the placebo effect in the context of religious beliefs and practices. Participants received an inert substance (tap water) with the verbal suggestion that the water would come from the Sanctuary of Lourdes (a major Catholic pilgrimage site with reports of miraculous cures). We investigated changes in resting-state functional connectivity (rsFC) in three brain networks (default mode, saliency, and cognitive control) associated with drinking placebo water.
Schienle A, Gremsl A, Wabnegger A (2021) Placebo effects in the context of religious beliefs and practices: a resting-state functional connectivity study. Front. Behaviour. neurosci. 15: 653359. doi: 10.3389 / fnbeh.2021.653359
Commentary
A total of 37 women who believed that water from the sanctuary of Lourdes would have a positive effect on their mental, emotional, and physical well-being participated in this study in two sessions.
The intervention method was to drink tap water labeled as "Lourdes water" (placebo) before a 15-minute resting scan in one session, and in the other (control) session they received tap water labeled as tap water.
They then rated their emotional state (valence, arousal) during the session, and immediately after each of the two sessions, they were interviewed and rated on specific thoughts, feelings, and experiences. Results showed that placebo decreased the rsFC of the frontoparietal cognitive control network and increased the rsFC of the saliency network (insula-cerebellum connections).
Participants rated their emotional state as very pleasant and calm during the session, and the ratings did not differ between the two conditions. Immediately after the session, participants reported an increase in the pleasant experience and emotional intensity for the "Lourdes water" condition.
In this resting-state functional connectivity (rsFC) study, specific placebos were investigated and their effects altered the strength of temporal correlations between specific brain regions. The intervention placebo increased the connectivity between the anterior insula and the posterior cerebellum.
However, despite several limitations of this study, such as the fact that only women were included, the recording time of the rsFC was relatively short, and a sample of healthy individuals was studied, the results of this study allow us to draw preliminary conclusions about placebo effects in the context of religious beliefs and practices.
We found that such placebo effects can enhance emotional and physical well-being and may lead to changes in rsFC in the brain's cognitive control/emotional saliency network.
