14 DAY TRIAL // Altruism is the human behavior of putting the welfare of others ahead of our own.
A team at Duke University Medical Center has recently found a particular brain zone whose activation is linked to whether people are prone to selfishness or to altruism. "Although understanding the function of this brain region may not necessarily identify what drives people like Mother Theresa, it may give clues to the origins of important social behaviors like altruism," said study investigator Scott A. Huettel, Ph.D., a neuroscientist at the Brain Imaging and Analysis Center.
"Why some people choose to act altruistically is unclear," says lead study investigator Dharol Tankersley, a graduate student in Huettel's laboratory.
The team used a technique called functional magnetic resonance imaging (fMRI), which employs harmless magnetic pulses to measure changes in the brain's neuronal activity, on 45 people, while they either played a computer game or watched the computer play the game on its own.
The successful playing of the game earned money for a charity of the study participant's choice in both variants.
"The scans revealed that a region of the brain called the posterior superior temporal sulcus was activated to a greater degree when people perceived an action -- that is, when they watched the computer play the game -- than when they acted themselves," Tankersley said.
This brain zone is generally linked to the mental configuration of social relationships.
The participants' altruism level was assessed based on their answers to questions about how often they engaged in different helping behaviors, and their brain scans were compared to their estimated level of altruism. The comparisons clearly linked increased activity in the posterior superior temporal sulcus to a person's higher altruistic behavior.
The scientists believe that altruistic behavior is determined by how people perceive the world rather than their temperament. "We believe that the ability to perceive other people's actions as meaningful is critical for altruism," Tankersley said.
Discovering the brain systems that permit people to feel the world as a series of meaningful interactions could shed a light on disorders, such as autism or antisocial behavior, including psychopath, triggered by low or absent interpersonal interactions. "The researchers are now exploring ways to study the development of this brain region early in life," Tankersley said. "Such information may help determine how the tendencies toward altruism are established."