People with more gray matter in brain behave more altruistically

Washington, July 12(ANI): A team of researchers from the University of Zurich has shown for the first time that there is a connection between brain anatomy and altruistic behaviour.

They found that the volume of a small brain region influences one's predisposition for altruistic behaviour.

The team, headed by Ernst Fehr, Director of the Department of Economics, showed that people who behave more altruistically than others have more gray matter at the junction between the parietal and temporal lobe, thus showing for the first time that there is a connection between brain anatomy, brain activity and altruistic behaviour.

To investigate whether differences in altruistic behaviour have neurobiological causes, volunteers were to divide money between themselves and an anonymous other person. The participants always had the option of sacrificing a certain portion of the money for the benefit of the other person. Such a sacrifice can be deemed altruistic because it helps someone else at one's own expense.

The researchers found major differences in this respect: Some participants were almost never willing to sacrifice money to benefit others while others behaved very altruistically.

The aim of the study, however, was to find out why there are such differences. Previous studies had shown that a certain region of the brain - the place where the parietal and temporal lobes meet - is linked to the ability to put oneself in someone else's shoes in order to understand their thoughts and feelings.

Altruism is probably closely related to this ability. Consequently, the researchers suspected that individual differences in this part of the brain might be linked to differences in altruistic behaviour.

And, according to Yosuke Morishima, a postdoctoral researcher at the Department of Economics at the University of Zurich, they were right: "People who behaved more altruistically also had a higher proportion of gray matter at the junction between the parietal and temporal lobes."

The participants in the study also displayed marked differences in brain activity while they were deciding how to split up the money. In the case of selfish people, the small brain region behind the ear is already active when the cost of altruistic behaviour is very low.

In altruistic people, however, this brain region only becomes more active when the cost is very high. The brain region is thus activated especially strongly when people reach the limits of their willingness to behave altruistically. The reason, the researchers suspect, is that this is when there is the greatest need to overcome man's natural self-centeredness by activating this brain region.

"These are exciting results for us. However, one should not jump to the conclusion that altruistic behaviour is determined by biological factors alone," said Ernst Fehr.

The volume of gray matter is also influenced by social processes. According to Fehr, the findings therefore raise the fascinating question as to whether it is possible to promote the development of brain regions that are important for altruistic behaviour through appropriate training or social norms. (ANI)