Religious believers may seem to share little with nonbelievers when it comes to thinking and judgment. But a new study by UCLA researchers finds that both Christians and nonbelievers use the same parts of the brain when asked to label articles of religious faith as true or false. A report summarizing the study is published today in PLoS ONE.
For both groups, the act of judging religious assertions increased activity in several regions of the brain collectively thought to play key roles in emotional judgment, processing uncertainty, assessing rewards and thinking about oneself.
The 15 Christian believers and 15 nonbelievers whose brains were scanned while assessing the truth of religious tenets were alike in one other respect: Both groups took longer to respond when they were asked to declare their own belief or disbelief in matters of faith than when they were asked to label neutral matters of fact true or false. It's not clear whether their responses were slowed by uncertainty in the face of the great questions, an emotional response to religious belief or a quick check of each individual's own place in the universe or the prospect of entry into heaven or hell.
When asked to consider the veracity of neutral claims (for instance, "Alexander the Great was a very famous military leader"), both groups tended to use parts of the brain that are strongly associated with memory retrieval.
"There is, of course, no reason to expect that any regions of the human brain are dedicated solely to belief and disbelief," the authors wrote. But, they added, the study showed that the opposing mental states of belief and disbelief are "intimately tied to networks involved in self-representation and reward."
One of the study's authors, Sam Harris, is the author of two bestselling books, "The End of Faith" and "Letter to a Christian Nation." Harris recently completed a doctoral dissertation in cognitive neuroscience at UCLA.
-- Melissa Healy