Neuroscientists at University College London (UCL) set up a situation in which people were coaxed to lie repeatedly and were awarded financially based on the magnitude of their lies. The results were more than they had envisioned.

"This study is the first empirical evidence that dishonest behavior escalates when it is repeated," said lead author Neil Garret, a researcher in the Department of Experimental Psychology at UCL.

In the experiments, 80 volunteers looked at photos of glass jars filled with different amounts of pennies. Then, via a computer, they were asked to advise a partner (an actor - unbeknownst to the participants) looking at a blurred image of the same jars as to how much money they contained.

Good lies and bad lies

In the first test, the volunteers were given an incentive to be honest.

"They were told that the more accurate their partner's estimate, the more money they would both receive," Garrett explained in a press briefing. In one experiment, a deliberate falsehood resulted in gains for both advisor and advised. In another, the participant was instructed that a lie would come at the expense of the partner.

"People lie the most when it is good for them and for the other person," said co-author Tali Sharot, also of UCL.

"When it is only good for them, but hurts someone else, they lie less."

Asked whether lies could be categorized into good and bad, Neil Garret explained to DW: "You could argue that lies are worse when they hurt the person being lied to. We found that people lie more when the lies benefit both of them compared to when lies cost the person being deceived. But escalation was similar in each of these scenarios."

Participants differed sharply on how far they wandered from the truth, and the rate at which their dishonesty escalated. But most volunteers not only easily slipped into a pattern of dissembling; they also ramped up the intensity of their lies over time.

Over a quarter of the participants underwent MRI scans during the experiments.

The part of the brain that processes emotions, the amygdala, responded strongly when lying occurred.

At least it did so at first.

As the lies grew bolder, the amygdala lit up less and less, a process the researchers called "emotional adaptation."

Better not to start…

"The first time you cheat on your taxes, for example, you might feel quite bad about it," Sharot said. "But the next time you cheat, you have already adapted, and there is less of a negative reaction to hold you back."

Whether it is "infidelity, doping in sports, making up data in science, or financial fraud, the deceivers often recall that small acts of dishonesty snowballed over time," said Sharot.

"They suddenly found themselves committing quite large crimes."

The more you lie, the better you get at it? From this particular study, that conclusion seems all but inescapable.

glb/cd AP,AFP