Mapping the Social Brain

How the brain responds to social status. Provided by Caroline Zink, NIMH

Friday, April 25th, 2008--

What goes through your head when you hear that you have a good reputation or find out that your social status is slipping? Researchers are starting to find out. By examining brain activity through functional magnetic resonance imaging (fMRI), two groups of researchers report how our brains respond to information about reputation and social status in the journal Neuron this week.

Caroline Zink, a neuroscientist from the National Institute of Mental Health, and colleagues developed a simple game in which participants played for money. The participants were competing against themselves only. The researchers told the players, however, that other people happened to be playing the same game simultaneously and then gave the participants information about how well they were doing compared to these other players.

Zink found that participants had a significant neural reaction to other players' success, despite the fact that these other players had no effect on an individual's monetary reward. "Simply viewing the face of someone of a different status, particularly someone superior to you, evoked a very strong brain response," says Zink.

An individual's neural reaction was mapped through fMRI. When a region in the brain is active its cells require increased oxygen: fMRI measures brain activity by tracking the flow of oxygenated blood.

When participants in Zink's study viewed a superior player, regions of the brain associated with social-emotional processing--like the amygdala--were activated. "If you think about it, it makes sense that you wouldn't have the same kind of emotional response if it was a computer," Zink says.

Understanding how our brains process social information has implications for understanding diseases with social symptoms, like autism and schizophrenia. Researchers can use this study to compare how patients with these diseases are processing hierarchical information, if they are processing that information all, Zink says.

Researchers also recently mapped the neural response to reputation. "Although we all intuitively know that a good reputation makes us feel good, the idea that good reputation is a reward has long been just an assumption in social sciences, and there has been no scientific proof," says Norihiro Sadato, a researcher at the National Institute for Physiological Sciences in Aichi, Japan and author of another study in Neuron this week.

Sadato and colleagues report that when people are told that they have a good reputation, regions of the brain associated with the reward are activated. A good reputation prompts a similar neural response to a monetary reward. "We found that these seemingly different kinds of rewards (good reputation vs. money) are biologically coded by the same neural structure, the striatum," Sadato writes in an email.

The striatum region of the brain also lit up in Zink's social hierarchy study. This region was activated when someone saw a superior player, suggesting social status and reputation are linked even at the cellular level.

--Flora Lichtman

Sources

Caroline Zink
Unit for Systems Neuroscience in Psychiatry National Institute of Mental Health National Institutes of Health

Norihiro Sadato
National Institute for Physiological Sciences (NIPS)
The Graduate University for Advanced Studies
Japan Science and Technology Agency (JST)
University of Fukui, Fukui, Japan