Damage to the part of the brain that controls social emotions changes the way people respond to thorny moral problems, demonstrating the role of empathy and other feelings in life-or-death decisions.
Asked to resolve hypothetical dilemmas — such as tossing a person from a bridge into the path of a trolley to save five others — people with damage to their ventromedial prefrontal cortex tended to sacrifice one life to save many, according to a study published Wednesday by the journal Nature.
People with intact brains were far less likely to kill or harm someone when confronted with the same scenarios.
The study suggests that an aversion to hurting others is hard-wired into the brain.
"Part of our moral behavior is grounded … in a specific part of our brains," said Dr. Antonio Damasio, one of the study's lead authors and director of the Brain and Creativity Institute at the University of Southern California…
The ventromedial prefrontal cortex processes feelings of empathy, shame, compassion and guilt. Damage to this part of the brain, which occupies a small region in the forehead, causes a diminished capacity for social emotions but leaves logical reasoning intact.