Evidence suggests that religious and spiritual states and behaviors are related to certain structures and processes in the brain, concludes a research review in the September/October issue of Harvard Review of Psychiatry. The journal is published in the Lippincott portfolio by Wolters Kluwer.
The studies in the review, with some important limitations, collectively suggest that the experience of religion/spirituality may have specific neurobiological correlates, writes Myrna M. Weissman, PhD, of Columbia University Vagelos College of Physicians and Surgeons and colleagues at New York State Psychiatric Institute.
Research points to brain areas and functions involved in religion and spirituality.
In recent years, many but not all studies have reported positive effects of religion and spirituality on mental health and well-being. For example, Dr. Weissman and her group found a lower rate of depression among people reporting that religion and spirituality was highly important to them. The group had been performing studies of brain structural and functional characteristics associated with religion and spirituality. The new report is the first comprehensive overview of research on the neurobiological correlates of religion and spirituality.
Led by James I. Rim, MD, JD, and Jesse Caleb Ojeda from Dr. Weissman's group at Columbia University, the review identified 25 studies of brain structural and functional characteristics associated with religion and spirituality, using techniques such as electroencephalography and functional magnetic resonance imaging. The studies used varied indicators of religious/spiritual states, such as church membership or "religious zeal," or religious behaviors such as praying. While most of the studies investigated Christian religions, other religions including Buddhism and Islam were represented as well.
Of the 25 studies, 21 found differences in neural activation or brain structure associated with religious/spiritual states or behaviors, compared to non-religious/spiritual control conditions. For example, some studies reported that the brain cortex was thicker in participants who said religion/spirituality was important to them. Another study linked religiosity to decreased activity in an interconnected brain network called the default mode network (DMN). Previous studies have suggested that higher DMN activity is associated with increased vulnerability to depression.
Other studies reported increased activity in certain brain areas during prayer or other religious practices, compared to non-religious tasks. However, the regions activated during religious behaviors were not consistent perhaps reflecting differences in study methods.
Most of the brain regions implicated are components of large-scale neural circuits involved in "higher-order functions" like emotional processing, empathy, and self-knowledge. Noting the wide distribution of these regions within the brain, Dr. Weissman and coauthors write, "Religion/spirituality is a multifaceted construct that should not be separated from its biological, environmental, and social contexts."
The researchers speculate that these brain regions might represent access to "an enhanced cognitive reserve that enables religious/spiritual people to cope better with negative emotions, more readily disengage themselves from excessive self-referential thinking, and ultimately be more resilient in the face of various psychopathologies."
While the studies offer new hypotheses into the neurobiological correlates of religion/spirituality, the researchers emphasize that they have major limitations and must be considered as preliminary. For example, some studies lacked comparison groups while many used non-validated measures of religiosity.
Thus the review suggests interesting hypotheses that require further testing, but are nowhere near definitive. Dr. Weissman and colleagues write, "Further studies with more rigorous study designs are warranted to elucidate the neurobiological mechanisms of religion/spirituality and their potential clinical applications."
Other investigators involved in the review include Connie Svob, PhD, JÃrgen Kayser, PhD, Elisa Drews, Youkyung Kim, Craig Tenke, PhD, and Jamie Skipper. The review was funded by the Templeton Foundation.
About the Harvard Review of Psychiatry
The Harvard Review of Psychiatry is the authoritative source for scholarly reviews and perspectives on a diverse range of important topics in psychiatry. Founded by the Harvard Medical School Department of Psychiatry, the journal is peer reviewed and not industry sponsored. It is the property of Harvard University and is affiliated with all of the Departments of Psychiatry at the Harvard teaching hospitals. Articles encompass major issues in contemporary psychiatry, including neuroscience, epidemiology, psychopharmacology, psychotherapy, history of psychiatry, and ethics.