Thursday, December 27, 2007
Faith is cerebral
Studies suggest the brain calculates math and ethics the same way
Whether it is a child's belief in Santa or a religious belief in the incredible miracle story, belief looms large at this time of year. Religion is the starting point, but this five-part series explores the many facets of belief, from the placebo effect to the neuroscience of belief and disbelief. Today, atheists on belief and disbelief.
Sam Harris may be the best-selling author of two books on the destructiveness of religion, but he has not given up on belief. Now a doctoral candidate in neuroscience at the University of California at Los Angeles, Mr. Harris and his colleagues have just published research that, they believe, maps for the first time where in the brain decisions are made about what we believe and do not believe.
Mr. Harris said he wanted to understand the biological process that allows people to accept certain descriptions of reality as valid.
Test subjects were scanned with an MRI while being asked to decide whether they believed the veracity of a particular statement. The researchers then looked for which parts of the brain "lit up."
They discovered the part of the brain used for lower cognitive functions -- such as deciding whether something smells good or bad, or assessing pain -- is also used to decide whether a proposition is true or false.
"Although many areas of higher cognition are likely involved in assessing the truth-value of linguistic propositions, the final acceptance of a statement as 'true' or its rejection as 'false' appears to rely on more primitive [processing]," Mr. Harris and his team wrote in the journal Annals of Neurology this month.
In an interview, Mr. Harris said there are many studies in neuroscience that have "broken down the boundaries between higher cognition and more primitive emotional processing." But this appears to be the first study to show that at the physical level of the brain.
He said it at first seemed surprising that "such a creaturely preference is operative here." But he added it makes sense because evolution had to employ ways to make sure the decisions we made would help us survive as a species.
"Belief really is the hinge upon which so much of human activity and human nature swings," said Mr. Harris, author of The End of Faith and its follow-up, Letter to a Christian Nation. "You are to an extraordinary degree guided by, or misguided by, what you believe. If you're a racist that is a result of what you believe about race. If you're a jihadist, that is built on what you believe about the Koran and supremacy of Islam. So belief is doing most of the work humans do. And it's an engine of conflict and reconciliation, so it really matters what people believe."
What was particularly surprising, he said, was that there were virtually identical patterns of brain activation whether someone was being asked to evaluate a straightforward proposition, such as two plus two equals four, or something that tested an ethical belief, such as whether torture is just or unjust.
"One obviously has very strong emotional association and one doesn't. So it is surprising that the coolest, calculated kind of reasoning we can engage in and the most emotionally laden in ethics could be so similar."
Mr. Harris's study concluded with the poetic notion that "truth may be beauty, and beauty truth, in more than a metaphorical sense and that false propositions may actually disgust us."
He said other studies have shown that when something disgusts us, the area of the brain known as the anterior insula is most active. In his study, it was the anterior insula that was most active when a proposition was rejected.
"The feeling of doubt, of not buying a statement, is on a continuum with other modes of rejection -- the epitome of which is disgust."
His next task will be to study how the brain evaluates religious beliefs and he expects that his results will be much the same as his latest study.
"I think on the basis of this study I expect to see that belief is belief is belief. Evaluating the belief that Jesus was the son of God is importantly different than evaluating the belief two plus two equals four. [But] there's going to be a common final pathway that governs whether the belief is accepted or rejected. There's something held in common between these modes of thinking."
clewis@nationalpost.com
Whether it is a child's belief in Santa or a religious belief in the incredible miracle story, belief looms large at this time of year. Religion is the starting point, but this five-part series explores the many facets of belief, from the placebo effect to the neuroscience of belief and disbelief. Today, atheists on belief and disbelief.
Sam Harris may be the best-selling author of two books on the destructiveness of religion, but he has not given up on belief. Now a doctoral candidate in neuroscience at the University of California at Los Angeles, Mr. Harris and his colleagues have just published research that, they believe, maps for the first time where in the brain decisions are made about what we believe and do not believe.
Mr. Harris said he wanted to understand the biological process that allows people to accept certain descriptions of reality as valid.
Test subjects were scanned with an MRI while being asked to decide whether they believed the veracity of a particular statement. The researchers then looked for which parts of the brain "lit up."
They discovered the part of the brain used for lower cognitive functions -- such as deciding whether something smells good or bad, or assessing pain -- is also used to decide whether a proposition is true or false.
"Although many areas of higher cognition are likely involved in assessing the truth-value of linguistic propositions, the final acceptance of a statement as 'true' or its rejection as 'false' appears to rely on more primitive [processing]," Mr. Harris and his team wrote in the journal Annals of Neurology this month.
In an interview, Mr. Harris said there are many studies in neuroscience that have "broken down the boundaries between higher cognition and more primitive emotional processing." But this appears to be the first study to show that at the physical level of the brain.
He said it at first seemed surprising that "such a creaturely preference is operative here." But he added it makes sense because evolution had to employ ways to make sure the decisions we made would help us survive as a species.
"Belief really is the hinge upon which so much of human activity and human nature swings," said Mr. Harris, author of The End of Faith and its follow-up, Letter to a Christian Nation. "You are to an extraordinary degree guided by, or misguided by, what you believe. If you're a racist that is a result of what you believe about race. If you're a jihadist, that is built on what you believe about the Koran and supremacy of Islam. So belief is doing most of the work humans do. And it's an engine of conflict and reconciliation, so it really matters what people believe."
What was particularly surprising, he said, was that there were virtually identical patterns of brain activation whether someone was being asked to evaluate a straightforward proposition, such as two plus two equals four, or something that tested an ethical belief, such as whether torture is just or unjust.
"One obviously has very strong emotional association and one doesn't. So it is surprising that the coolest, calculated kind of reasoning we can engage in and the most emotionally laden in ethics could be so similar."
Mr. Harris's study concluded with the poetic notion that "truth may be beauty, and beauty truth, in more than a metaphorical sense and that false propositions may actually disgust us."
He said other studies have shown that when something disgusts us, the area of the brain known as the anterior insula is most active. In his study, it was the anterior insula that was most active when a proposition was rejected.
"The feeling of doubt, of not buying a statement, is on a continuum with other modes of rejection -- the epitome of which is disgust."
His next task will be to study how the brain evaluates religious beliefs and he expects that his results will be much the same as his latest study.
"I think on the basis of this study I expect to see that belief is belief is belief. Evaluating the belief that Jesus was the son of God is importantly different than evaluating the belief two plus two equals four. [But] there's going to be a common final pathway that governs whether the belief is accepted or rejected. There's something held in common between these modes of thinking."
clewis@nationalpost.com
# posted by James W Breckenridge : 2:08 PM
