More over 80% of the world’s population considers themselves religious or spiritual. However, research on the neurology of spirituality and religion has been limited. Previous research has employed functional neuroimaging, which involves having a brain scan while executing a task to observe which parts of the brain light up. However, these correlative studies have provided a skewed and often contradictory image of spirituality.
A new study lead by Brigham and Women’s Hospital researchers adopts a novel way to mapping spirituality and religion, discovering that spiritual acceptance may be localized to a particular brain circuit. This brain circuit is focused in the periaqueductal gray (PAG), a brainstem area involved in a variety of processes like as fear training, pain regulation, altruistic behaviors, and unconditional love. The team’s results have been published in the journal Biological Psychiatry.
“Our findings suggest that spirituality and religiosity are rooted in fundamental neurobiological dynamics and are deeply woven into our neuro-fabric,” said corresponding author Michael Ferguson, PhD, a principal investigator at the Brigham and Women’s Hospital’s Center for Brain Circuit Therapeutics. “We were astounded to discover that this brain circuit for spirituality is situated in one of the brain’s most evolutionarily maintained regions.”
Ferguson and colleagues conducted their research using a method known as lesion network mapping, which enables researchers to map complex human behaviors to particular brain circuits based on the locations of brain lesions in patients. The researchers used a previously published dataset of 88 neurosurgical patients having surgery to remove a brain tumor. The sites of the lesions were spread across the brain. Before and after surgery, patients completed a survey that included questions regarding spiritual acceptance. The researchers verified their findings using a second dataset of more than 100 individuals with lesions induced by severe head trauma during the Vietnam War. These participants also completed questionnaires that contained religious-related questions (such as, “Do you consider yourself to be religious? Is it true or false? “..
Thirty of the 88 neurosurgery patients had a drop in self-reported spiritual belief before to and after neurosurgical brain tumor removal, 29 had an increase, and 29 had no change. The scientists discovered that self-reported spirituality matched to a unique brain circuit focused on the PAG using lesion network mapping. The circuit included both positive and negative nodes, and lesions that disrupted these nodes either reduced or boosted self-reported spiritual beliefs. The second dataset’s religiosity results corroborated similar conclusions. Furthermore, the researchers discovered multiple case reports of individuals who became hyper-religious after having brain injuries that impacted the negative nodes of the circuit in a study of the literature.
The spirituality circuit interacted with lesion areas linked with various neurological and mental symptoms. Lesions linked with parkinsonism, for example, crossed positive sections of the circuit, as were lesions associated with diminished spirituality. Lesions related with delusions and alien limb syndrome interacted with negative areas linked to enhanced spirituality and religion.
“It’s crucial to stress that although these overlaps may be useful for identifying similar traits and relationships, they should not be over-interpreted,” Ferguson said. “Our findings, for example, do not suggest that religion is an illusion, that previous religious leaders had alien limb syndrome, or that Parkinson’s disease is caused by a lack of religious faith. Instead, our findings suggest to the deep foundations of spiritual ideas in a region of our brain that has been linked to a variety of critical tasks.”
The authors point out that the datasets they utilized do not give detailed information on the patient’s background, which might have an impact on spiritual views, and that patients in both datasets were mostly Christian. They would need to duplicate their research across numerous backgrounds to determine the generalizability of their findings. The team is also interested in disentangling religion and spirituality in order to better understand the brain circuits that may be causing disparities. Ferguson would also want to study clinical and translational applications for the results, such as determining the function of spirituality and compassion in therapeutic therapy.
“Medicine and spirituality have only lately been separated from one another. Across nations and civilizations, there seems to be a perpetual marriage between health and spirituality “Ferguson said. “I’m curious in how our knowledge of brain circuits may assist construct scientifically based, clinically applicable questions about how healing and spirituality might co-inform one other.”
An NIH Ruth L. Kirschstein National Research Service Award (NRSA) Institutional Research Training Grant (T32MH112510), the Shields Research Grant from the Child Neurology Foundation, the Sidney R. Baer, Jr. Foundation, the Nancy Lurie Marks Foundation, the Mather’s Foundation, the Kaye Family Research Endowment, and the National Institutes of Health funded this research (grants R01 MH113929, R01 MH115949, and R01 AG060987).