Billions of people around the world rely on religious beliefs and spirituality to make their lives fulfilling and give them a sense of purpose. Now, researchers at Brigham and Women’s Hospital have found that the beliefs of religious individuals (their “spiritual acceptance”) can be linked to a particular circuit in the brain.
The study’s investigators used datasets taken from 88 neurosurgical patients who underwent surgery for a brain tumor and who had brain lesions (damaged parts of the brain) corresponding to the former site of the tumor. The location of the lesions was inconsistent between patients, as the location of their tumors differed.
All patients filled out a questionnaire prior to and after surgery to gauge their spiritual convictions. After undergoing brain tumor resection, 30 of the 88 patients reported a decline in their spiritual beliefs, while 29 patients reported an increase. The remaining 29 patients reported no change.
Using a technique called lesion network mapping, the researchers mapped the patients’ spiritual beliefs to a circuit in a region of the brain called the periaqueductal gray (PAG). The circuit contained both positive and negative nodes, which explained why the patients, whose brain lesions affected either node, reported both increases and decreases in spirituality.
The researchers compared their results with another dataset of 100 Vietnam War veterans who had sustained head trauma and developed brain lesions as a result. In both datasets, the researchers found case reports of patients who became “hyper-religious” after experiencing brain lesions that targeted the negative node in their PAG circuit.
Spirituality “woven into our neuro-fabric”
“Our results suggest that spirituality and religiosity are rooted in fundamental, neurobiological dynamics and deeply woven into our neuro-fabric,” said study author Michael Ferguson, PhD, a principal investigator in the Brigham’s Center for Brain Circuit Therapeutics. “We were astonished to find that this brain circuit for spirituality is centered in one of the most evolutionarily preserved structures in the brain.”
The study’s limitations
The study’s authors admitted that the patients they examined were overwhelmingly from a Christian background, and not much information was provided on the patients’ upbringing (which can influence their religious beliefs). If the study had been conducted on patients of a different faith, the results may have varied. Nonetheless, Ferguson believes that the study’s results could lead to spirituality being incorporated in a clinical setting.
“I’m interested in the degree to which our understanding of brain circuits could help craft scientifically grounded, clinically-translatable questions about how healing and spirituality can co-inform each other,” said Ferguson.
Written by Natan Rosenfeld