Study shows left side of brain more active in immoral thinking

From PhysOrg:

BrainBecause the brain is so complex, researchers are forced to devise all manner of different types of tests in trying to understand not just how it works, but which parts of it do what. To that end, a diverse group of scientists from several universities across the U.S. got together to work on the problem of which parts of the brain, if any specifically, are involved in analyzing and making moral judgments. To find out, or at least learn more, they devised three experiments meant to test the busyness of the brain, measured by blood flow, to certain regions, when presented with immoral situations. They have published the results of what they found in the journal Frontiers in Evolutionary Neuroscience.

The idea behind all three experiments was to present volunteers with material that is generally believed to be immoral while watching blood flow patterns in their brains using fMRI, as compared to what happens when moral or neutral material is viewed. In the first study, volunteers were told that they would be engaging in a memory test. They were then shown a series of statements, followed by another series of statements after that. During the second series they were asked to press a button to indicate if the statement they were being shown had been among those shown in the first series. The statements shown were divided into four classes: pathogen related (non-sexually gross stuff), incestuous acts, nonsexual immoral acts and neutral acts. In the second study, volunteers were shown three types of statements in random order: 50 examples describing acts that most people think of as immoral, 50 statements that most think of as pro-moral (morally good) and 50 statements that most people think of as neutral. And finally, in the third study, volunteers were shown three types of pictures in random order: immoral, non-moral (negative without morality), and neutral. After analyzing and normalizing the data, the researchers found that the left hemisphere of the brain showed increased blood flow in response to immoral stimuli throughout all three studies, while the right did not.

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