In the group of 88 neurosurgical patients, some reported less spiritual faith before and after surgery, some more, and some didn’t report a change. Going off of those reports, researchers were able to map lesions in the brain and identify a specific brain circuit associated with spirituality.
That brain circuit was centered in a brainstem region called the periaqueductal grey (PAG), which has positive and negative nodes. When lesions disrupted a positive node, spiritual beliefs seemed to decrease and vice versa. When lesions disrupted a negative node, it increased spiritual belief. The set of data from the other 100-plus patients supported these findings.
As the study authors note, this research suggests “spirituality and religiosity map to a common brain circuit centered on the periaqueductal grey, a brainstem region previously implicated in fear conditioning, pain modulation, and altruistic behavior.”