You know how your mom always told you not to start lying because one fib would lead to more? Part of that age-old advice stems from the simple fact you usually have to keep lying to cover the initial untruths you dished out. But as Alice Park of Time reports, neuroscience now shows that we all should listen to Mom to keep our emotional sense of right, wrong and self, too.

The experiment

Led by Tali Sharot, researchers at University College London devised several scenarios in which participants repeatedly lied to their partners. The researchers used fMRI technology to scan the brains of the participants during the experiment. They found that activity in the amygdala decreased the more dishonest participants were.

The results, dissected

Your amygdala is an almond-shaped group of neurons deep in your brain's medial temporal lobe, at the end of the hippocampus. Part of the limbic system, it's essentially your brain's emotional processing and arousal hub. Sharot and her colleagues theorize that, the more you play Pinocchio and lie, the more the internal conflict of lying diminishes. You stop feeling so bad about what you're doing, essentially deconditioning yourself from caring or worrying. That's bad news, of course, because if you don't feel like lying is a big deal anymore, or if you're no longer conflicted about it, it's incredibly easy to tack another lie onto the last one and keep snowballing.

Lying and work

Sharot's work has strong implications for handling truth--or rather, the lack thereof--in the workplace. Because amygdala response goes down the more someone lies, you might have a harder time getting them to admit they haven't been honest the longer you let them fib, as they won't be as motivated by their sense of internal conflict to come clean. Confront the liar in a safe, private space as soon as you can for this reason. At the same time, the experience of getting away with lie after lie might lead the liar to see you as gullible and unintelligent, convincing them they won't face negative consequences if they lie about other things. Lastly, you can consider the research when trying to resolve conflicts resulting from the lies. If someone has lied so much that they show zero remorse, for instance, a dismissal might be better than a reprimand.

As a final note, Sharot and her team also found that the amygdala activity decreased primarily when people were lying to benefit themselves. Sharot thinks people might learn from the emotional arousal lying causes. If they can feel the arousal less, the less likely they are to see the lies as being contrary to their positive sense of self as an honest person. Here, your best bet is not to brush the truth under the rug, but rather to show the liar they can work to become the honest person they desire themselves to be. Dish out consequences for dishonesty, but give some positive reinforcement (reward) for telling the truth, too.