Chicago Tribune | Brain study maps mechanics of decision-making

PASADENA, Calif. -- Which life do you value more: That of a beetle or that of a panda? How about a rabbit's versus a tiger's?

Researchers at the California Institute of Technology are asking such things while monitoring blood flow in the brains of the people being questioned. Their aim is to determine which parts of the brain are most active when people make such judgments.

The researchers' goals are numerous, but at the core of their work is a question about human nature: What part of us--the logical part, the creative part, fear or a combination of factors--enters into decision-making, including moral judgments?

Because blood flow increases to parts of the brain being used, researchers are trying to sort out these questions with the help of volunteers and a functional magnetic resonance imaging, or fMRI, machine.

Real-time effect

The fMRI differs from other MRIs the way a video camera differs from a still camera in that the fMRI allows scientists to watch the flow of blood. A regular MRI would provide only a snapshot of a given moment.

By watching the surges of blood, researchers can determine whether people are using logical parts of the brain, or the emotional and artistic parts, or parts where gathered information is processed.

While the research centers on the human brain, the professor in charge of the work is a University of Chicago-trained economist and his graduate student assistant is an economist as well.

"How do we attach a price to things?" asked lead researcher Colin Camerer, the Cal Tech professor.

The research has such potential applications as finding out what products might appeal to a consumer. But it is wider than that, Camerer said: "How do we attach a price to things that are not a product, like clean air?"

Such questions arose after the 1989 Exxon Valdez oil spill off the coast of Alaska.

"People would be asked how much they would be willing to pay to clean up," Camerer said. "They came up with different prices, but if you asked what they would pay to never let it happen, they would say `priceless.'"

A reporter who recently went through the testing was placed on a table, his head put in a harness and his eyes covered with goggles. His ears were covered with earphones equipped with a microphone. He was given two control boxes, one placed in each hand.

After an initial test of the equipment and then a six-minute body scan, the fMRI was focused on his head. A series of images appeared in the goggles, and questions were asked to determine value in various situations.

One image was of a fierce-looking crocodile with its jaws open. The questioner asked how much the subject would be willing to pay to have the animal killed painlessly. One of the hand controls enabled the subject to set a dollar value, and the other device allowed him to select that value as his choice.

Other images and questions followed. Typically the questions asked to fix a value to painlessly kill a giraffe or a butterfly or a lion or a puppy.

After the test, Camerer said that the reporter's results were in many ways similar to those of people previously examined.

"People tend to value the lives of large animals more than small ones," Camerer said. He said that when the choice was between a human and an animal, humans were always valued higher.

That was one of the similarities. But the reporter placed larger values on the lives of some smaller animals--a kitten and a puppy--than the people tested earlier.

Camerer said that the difference could possibly be explained by the fact that all of the previous results came from tests on men in their 20s who were summer students at Cal Tech, a pretty homogenous group.

Camerer said he guessed that the reporter's decisions were probably more typical of the population in general.

Other areas explored

Researchers at other universities are using fMRIs to study people's reactions to political figures, including President Bush.

Other experiments are being carried out as well. Among them are tests to measure people's fear of the unknown and how trust is built between individuals.

The research so far has backed up known neurological science.

"Most complicated activities take many parts of the brain collaborating," Camerer said.

One area of the brain active in coordinating input from other parts is known as the insula, located in the front of the brain in the cerebral cortex.

The Cal Tech research is supporting earlier work done at UCLA that suggested the insula processed "social pain," such as shame and remorse.

Graduate student Ming Hsu, who is working with Camerer, said it was believed that people inclined to take risks--such as entrepreneurs--may have brains in which signals from the insula are weak or not received, perhaps making fear and hesitation at risk-taking far less than in other people.

Using the fMRI, Camerer and Hsu hope to study such entrepreneurial brains to see how busy the insula is when subjects are asked about risk-taking.

So far 12 people have participated in the Cal Tech research, but Camerer hopes to expand that number and vary the type of people tested.

He also hopes to explore work done earlier at Yale University that touches on people's brain activity when confronted with the faces of people of different races.

That Yale research found that when white people were shown the face of an unfamiliar black person, their brains signaled fear. If they were shown the face of a familiar black person, that reaction was not seen.

"Show them Colin Powell and there is no problem," Camerer said, referring to the former secretary of state.

Future applications

He said that area of research could have applications in labor economics, helping businesses measure and better understand the brain's reaction to people of different races and ethnicity, sex, even size and weight.

"How would a young human resources officer's brain react when interviewing a 55-year-old prospective employee?" Camerer asked.

"There is a chance that racism is happening in a way people don't even know," he said.

Another application for the research is studying how people function when forced to cooperate with another person to resolve a problem. Such work requires trusting the other individual, Camerer said.

"People who are self-important don't do well at these two-person games," he said. "If you think less about yourself and can put yourself in another person's shoes, you do better."