Study suggests `born-again' believers have smaller brains

May 24, 2011

DURHAM, N.C. (RNS) For decades, mainline Protestants have been beset by
bad news: declining numbers, aging membership, waning cultural

A new study from Duke University Medical Center, however, gives
these Protestants one reason for cheer: they seem to have larger brains
than born-again Christians, Roman Catholics and the religiously

The study, which examined the hippocampus region of the brain, found
that Protestants who did not have a "born again" experience had
significantly more gray matter than either those who reported a
life-changing religious experience, Catholics, or unaffiliated older

The study, funded by the National Institutes of Health and the
Templeton Foundation, included at least two MRI measurements of the
hippocampus region of 268 adults between 1994 and 2005.

It found an association between participants' professed religious
affiliation and the physical structure of their brain. Specifically,
those identified as Protestant who did not have a religious conversion
or born-again experience -- more common among their evangelical brethren
-- had a bigger hippocampus.

Amy Owen, a psychologist who did a post-doctoral fellowship at Duke
and was the main writer for the study, said she hoped others would try
to reproduce the study or offer other reasons for the association.

"There may be more factors responsible for the correlation," she
said of the study published on March 30 in "PLoS One," a peer-reviewed,
open-access, online publication.

Participants, all 58 or older, were initially recruited for a larger
study on the effects of depression in the elderly. That study is
ongoing. For this study, researchers ruled out depression or lack of
social support as reasons for the smaller brain size, or hippocampal

The hippocampus is an area buried deep in the brain that helps
regulate emotion and memory. Atrophy or shrinkage in this region of the
brain has long been linked to mental health problems such as depression,
dementia and Alzheimer's disease.

So why would born-again Protestants, Catholics and those with no
religious affiliation have a smaller hippocampus? Researchers speculate
it may have something to do with the stress of belonging to a minority
group. Chronic stress floods the brain with hormones that, over time,
may damage the hippocampus.

Sociologists of religion, meanwhile, aren't buying it. They say the
researchers' theory flies in the face of U.S. religious demographics.
While it's true that evangelicals are a minority, they're a sizable one
-- 40 percent of the U.S. population, according to Gallup Polls -- and
not exactly a stressed-out minority, especially in the South.

"There are probably more born-again Protestants than non-born-again
Protestants, and just about as many Catholics as either born-again or
non-born- again Protestants," said David Roozen, sociologist of religion
at Hartford Seminary.