Explore the neurobiology of altruism, focusing on the differences in brain structure and function between individuals with psychopathic traits and those who exhibit extraordinary altruism, particularly altruistic kidney donors. By comparing brain activity and structure in both groups, the research suggests that the amygdala, a brain region crucial for processing fear and social emotions, plays a key role in both psychopathy and altruism. The study highlights the possibility that individuals with high levels of altruism have an enhanced capacity to recognize fear in others and a stronger connection between the amygdala and regions involved in parental care, leading them to act in a protective and caring manner towards strangers.