"I never lie"

In the 1978 film, Superman, there's a scene in which the guy in the blue tights and red cape is with Lois Lane up on her balcony, giving his first interview. The two have this exchange:

Lois Lane: I mean, why are you here? There must be a reason.
Superman: Yes. I'm here to fight for truth, and justice, and the American way.
Lois Lane: [Laughs] You're gonna end up fighting every elected official in this country!
Superman: I'm sure you don't really mean that, Lois.
Lois Lane: I don't believe this.
Superman: Lois, I never lie. (The last line can be seen here.)

Of course Superman does lie, if not by commission, then frequently by misdirection and by omission--for instance, not telling people that Superman and Clark Kent are the same person.

But his "never lie" statement conveys his boy-scout-like moral code: he tries to be honest and forthright. Is Superman's honesty a superpower--a pattern of behavior that requires superhuman effort? That is, does it require a strong "will" to be honest? Or are people who are basically honest, like Superman, simply not tempted to lie, and so no great effort is required to tell the truth?

This is a question that psychologist Joshua Greene and graduate student Joseph Paxton set out to investigate. In their study, they gave participants an opportunity to make money by accurately predicting the outcome of flips of a coin. For some coin flips, participants were asked to make their predictions aloud; for other coin flips, participants did not but instead after the coin flip reported whether their prediction had been accurate (and thus in this second type of procedure participants would easily lie without anyone else knowing that they were doing so). Here's the twist: all of this was happening while participants were in an fMRI scanner.

Participants should make accurate predictions, on average, in about 50% of the coin flips and that's what happened in the first condition--in which they reported their predictions out loud. In the second condition--in which people didn't make a public prediction before the coin flip but instead reported after the flip whether their prediction was correct-people reported being correct over 80% of the time. As with the first condition, the chance of correctly predicting is 50%, so participants must have been lying about their accuracy some of the time.

Examining the data more closely, it turns out that not all participants lied during the second condition. Some participants (the "honest" participants) reported 50% accuracy rates in the second condition, the same as in the first condition, and what is statistically plausible. It seems that these folks aren't tempted to lie, and their brain scans did not look different between the first and second conditions, which suggests that they weren't tempted to lie when they had the opportunity and motive (remember, the more accurate their predictions, the more money they would receive). Their honesty was relatively effortless, like Superman's appears to be.

In contrast, the folks who lied in the second condition (the "dishonest" participants) had more activity during both conditions in the parts of the brain involved in planning and decision-making. This set of brain areas was activated when participants had to decide what to say. It would appear that for these folks, being honest--at least about coin flip predictions--takes more work.

The study authors suggest that parents may be best off trying to instill honesty in their very young children so that they grow up with honesty that is automatic, effortless, and not subject to temptation. How do you think Ma and Pa Kent instilled honesty in Clark?

Copyright 2011 by Robin S. Rosenberg. All rights reserved.

Robin S. Rosenberg is a clinical psychologist. Her website is DrRobinRosenberg.com