Category Archives: Scientific American MIND

Smokers’ Choice

Smokers tend to resist antismoking efforts that rely on “rational” approaches such as taxes, and researchers have pointed to confounding influences, including social factors and addiction. But differences in smokers’ decision-making processes may also be at play.

A recent study from the Baylor College of Medicine found that smokers and nonsmokers react differently to news of how much they could have made in a stock-market game. The feedback was purely incidental: it offered no financial incentive to adjust one’s investment strategy, yet nonsmokers were swayed by what might have been and changed their tactics. Smokers ignored the input, even though they processed the information in the same part of the brain as their nonsmoking peers did.

The study does not address whether smokers’ behavior is a cause or effect of their addiction but rather it adds to the growing list of ways in which human beings sometimes ignore reason when it comes to decision-making. In the book Predictably Irrational (HarperCollins, 2008) behavioral economist Dan Ariely of the Massachusetts Institute of Technology catalogues a bevy of errors, biases and otherwise illogical human behavior. Other behavioral economists are doing the same on the premise that these absurdities are understandable, and they are just beginning to team up with neuroscientists to try to tease out the roots of decision-making biases in the brain.

The hope is that this knowledge will one day inform policy. To combat smoking, for example, policymakers could “use evidence of what brain areas are active during the [decision-making] process to design other strategies” more nuanced than taxation, says behavioral economist Colin Camerer of the California Institute of Technology.

The field of neuroeconomics is in its infancy, however. Neuroeconomists agree with behavioral economists that in the future it will be possible to use our irrationalities to our advantage, but as for whether their work could soon steer policy, “I think it’s just too early” to make a decision, Ariely says.

First published by Scientific American MIND: [html]  [pdf].

Some Are More Equal

Life may not be fair, but humans have a strong bias for fairness. In experiments humans will generally reject or punish a partner who offers noticeably less than half a shared reward, even if they wind up empty-handed. Chimps, it turns out, are not so picky and will (rationally, an economist might point out) take whatever they can get, according to an October 2007Science paper. So what could explain this difference between our closest living relatives and us?

The answer may lie in the social relationships that influence so many of our actions. Recent studies of primate fairness seem to contradict each other–unless you consider exactly who is cheating whom.

In 2003 a provocative study led by Sarah F. Brosnan, now at Georgia State University, concluded that capuchin monkeys were exhibiting humanlike social indignation when they turned down unfair deals. The monkeys refused to perform tasks if they saw companions getting better rewards for the same work. They threw tantrums, and their food rewards, to protest the unequal treatment.

In 2006, however, a group at American University reported the opposite result–their capuchins’ behavior was not affected by the food their partners got. In response, Brosnan’s group released an updated study, again showing the capuchins’ penchant for fairness. But some experts are still not convinced–Clive Wynne of the University of Florida warns that the different study designs make comparisons “messy.”

Brosnan argues that social relationships are more important than the other groups are accounting for. Her group found that chimpanzees were more likely to accept unfair deals from members of their social group than from outsiders. In another study, humans accepted unfair deals from a computer but not from people. These results imply that relationships matter when primates judge fairness, Brosnan says, and “may explain the failure to find a response in the [Science] study.” The chimps, in other words, may have been willing to accept unfair offers because they came from old pals.

Studying animal fairness could ultimately help us understand human cooperation and justice–but the jury is still out.

First published by Scientific American MIND: [html] [pdf].