"What we have shown is there is a part of the brain that is involved in making simple economic decisions that is closely tied in to the parts of the brain that process emotions," Smith says. "We've also shown that for the same economic decisions, there's a part of the brain that is known to be involved in mathematics and other higher reasoning processes.
"The behavior they generate is often the same," at least for the level of mental activity required for the experiment.
In the neuroimaging experiment, both "minds" seemed to work together without any serious conflict. But Smith speculates that in the real world, that may not always be the case.
Participants in the study were presented with relatively simple and straightforward issues, and that may have "predisposed" them to use the more rational part of their brains, he says.
"Many situations in real life are not as formally simple as the stimuli we gave our subjects," he says. Taking a giant leap beyond the limits of his current research, Smith says it's possible that in a more complex setting the two networks might get into a bit of a fight themselves.
Our more primitive mind might overwhelm our more modern mind, making us more reactive than rational. Or our mathematical mind might tell us to take the gamble and ignore the risk. Yet at least some of the time we're probably getting conflicting signals from both "minds."
"This could say why some people are conflicted about this war," he says. "We all, in our gut, want our men and women to do well, but in our lofty heads, this ivory tower, we're saying why in the hell are we there in the first place."
Many are, as the man says, of at least two minds.
Results of the study were published in the journal Management Science. In addition to Smith, the team included John Dickhaut of the University of Minnesota, Kevin McCabe of George Mason University, and Jose V. Pardo of the Veterans Affairs Medical Center and the University of Minnesota.
Lee Dye’s column appears weekly on ABCNEWS.com. A former science writer for the Los Angeles Times, he now lives in Juneau, Alaska.