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Brain Damage could Affect Moral Judgment

A study at the University of Iowa, published in this months Nature, links brain damage in a certain section of the brain to change in theoretical moral decisions. According to the study, people who sustained a rare injury area in an area of the brain behind the forehead, inches behind the eyes, expressed an increased willingness to kill or harm other people in order to save others? lives. Previous studies linked this region of the brain with moral decision making. This new study demonstrates that a very specific kind of emotion-based judgment is altered when the region is injured, even to an extent that people with an injury could endorse the suffocation of an infant if that would save more lives.

?I think it?s very convincing now that there are at least two systems working when we make moral judgments,? Joshua Greene, a psychologist at Harvard, said. ?There?s an emotional system that depends on this specific part of the brain, and another system that performs more utilitarian cost-benefit analyses which in these people is clearly intact.?

Apparently, the ventromedial area, which is a primitive part of the cortex, has evolved to help humans navigate social interactions. The area is connected to the brain stem, transmitting physical sensations of attraction or discomfort, and the amygdala, a gumdrop of neural tissue that registers threats. ?This area, when it?s working, will give rise to social emotions that we can feel, like embarrassment, guilt and compassion, that are critical to guiding our social behavior,? Dr. Antonio Damasio, a co-author of the study and a neuroscientist at the University of Southern California, said.