Fairness Is a Hard-Wired Emotion

May 9 -- THURSDAY, May 8 (HealthDay News) -- The belief that things should be divided fairly among members of a group isn't just a matter of culture or reason -- it's an emotion that's built into the human brain.

That's the suggestion of a new study that posed the question: Is it better to give food to some hungry children while others go hungry? Or is it better that every child get a share, albeit a smaller one?

"People prefer equity, when all things are equal, to efficiency," said study lead researcher Ming Hsu, a fellow at the University of Illinois Beckman Institute for Advanced Science and Technology.

And different regions of the brain are involved when making decisions involving fairness or efficiency, he said.

"In terms of the brain, we find areas of the insular cortex are activated when people were choosing the equitable allocation of food," Hsu said. "Given the involvement of the insular cortex in emotions and fairness judgments, we conclude that emotions are underlying equity judgments."

Other areas of the brain are activated when people are making judgments about efficiency, he said.

But, not everyone is sensitive to equity, Hsu noted. "Some people care less about equity, and that's associated with a lower sensitivity in their insula," he said. "When these people are confronted with inequitable situations, their insula is activated less."

The study, by researchers at the University of Illinois and the California Institute of Technology, was published in the May 8 issue of Science.

For the study, the volunteers were hypothetically asked to distribute food to children in an orphanage in Uganda. The children would be given the cash equivalent of 24 meals, a "gift" from the research team to the orphanage.

But, a number of meals would have to be cut for some of the children. So, the volunteers were given two options to deal with the problem.

In one option, 15 meals could be taken from one child, or 13 from another child, or five from yet another child, for instance. Choosing this option, the total number of meals lost would be less, but one child would suffer from all cuts. Efficiency would be maintained at the expense of equity.