Religious Experiences Shrink Part of the Brain

A study links life-changing religious experiences, like being born again, with atrophy in the hippocampus

The article, “Religious factors and hippocampal atrophy in late life,” by Amy Owen and colleagues at Duke University represents an important advance in our growing understanding of the relationship between the brain and religion. The study, published March 30 in PLoS One, showed greater atrophy in the hippocampus in individuals who identify with specific religious groups as well as those with no religious affiliation. It is a surprising result, given that many prior studies have shown religion to have potentially beneficial effects on brain function, anxiety, and depression.

A number of studies have evaluated the acute effects of religious practices, such as meditation and prayer, on the human brain. A smaller number of studies have evaluated the longer term effects of religion on the brain. Such studies, like the present one, have focused on differences in brain volume or brain function in those people heavily engaged in meditation or spiritual practices compared to those who are not. And an even fewer number of studies have explored the longitudinal effects of doing meditation or spiritual practices by evaluating subjects at two different time points.

In this study, Owen et al. used MRI to measure the volume of the hippocampus, a central structure of the limbic system that is involved in emotion as well as in memory formation. They evaluated the MRIs of 268 men and women aged 58 and over, who were originally recruited for the NeuroCognitive Outcomes of Depression in the Elderly study, but who also answered several questions regarding their religious beliefs and affiliation. The study by Owen et al. is unique in that it focuses specifically on religious individuals compared to non-religious individuals. This study also broke down these individuals into those who are born again or who have had life-changing religious experiences.

The results showed significantly greater hippocampal atrophy in individuals reporting a life-changing religious experience. In addition, they found significantly greater hippocampal atrophy among born-again Protestants, Catholics, and those with no religious affiliation, compared with Protestants not identifying as born-again.

Read the whole story in Scientific American