http://en.wikipedia.org/wiki/Altruism Jorge Moll and Jordan Grafman, neuroscientists at the National Institutes of Health and LABS-D'Or Hospital Network (J.M.) provided the first evidence for the neural bases of altruistic giving in normal healthy volunteers, using functional magnetic resonance imaging. In their research, published in the Proceedings of the National Academy of Sciences USA in October, 2006,^[9] they showed that both pure monetary rewards and charitable donations activated the mesolimbic reward pathway, a primitive part of the brain that usually lights up in response to food and sex. However, when volunteers generously placed the interests of others before their own by making charitable donations, another brain circuit was selectively activated: the subgenual cortex/septal region. These structures are intimately related to social attachment and bonding in other species. Altruism, the experiment suggested, was not a superior moral faculty that suppresses basic selfish urges but rather was basic to the brain, hard-wired and pleasurable.^[10]
Another experiment funded by the National Institutes of Health and conducted in 2007 at the Duke University in Durham, North Carolina suggests a different view, "that altruistic behavior may originate from how people view the world rather than how they act in it".^[11] In the study published in the February 2007 print issue of Nature Neuroscience, researchers have found a part of the brain that behaves differently for altruistic and selfish people.
The researchers invited 45 volunteers to play a computer game and also to watch the computer play the game. In some instances, successful completion of the game resulted in them winning money for themselves, and in other instances, it resulted in money being donated to a charity which each person had chosen. During these activities, the researchers took functional magnetic resonance imaging (fMRI) scans of the participants' brains and were "surprised by the results". Although they "were expecting to see activity in the brain's reward centres" and that "people perform altruistic acts because they feel good about it", what they found was that "another part of the brain was also involved, and it was quite sensitive to the difference between doing something for personal gain and doing it for someone else's gain". That part of the brain is called the posterior superior temporal cortex (pSTC).
In the next stage, the scientists asked the participants some questions about type and frequency of their altruistic or helping behaviours. They then analysed the responses to generate an estimate of a person's tendency to act altruistically and compared each person's level against their fMRI brain scan. The results showed that pSTC activity rose in proportion to a person's estimated level of altruism. According to the researchers, the results suggest that altruistic behavior may originate from how people view the world rather than how they act in it. "We believe that the ability to perceive other people's actions as meaningful is critical for altruism", said lead study investigator Dharol Tankersley.^[12]