Scientists Identify The Brain's "Honesty Switch"

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Have you ever experienced a moment when you’ve teetered between telling the truth and telling a lie? Researchers at Virginia Tech’s Department of Psychology, fascinated by the brain’s methods for weighing consequences, decided to investigate.

From Science Daily:

“‘We asked whether there’s a switch in the brain that controls the cost and benefit tradeoff between honesty and self-interest,’ [Assistant Professor Pearl] Chiu said. ‘The answer to this question will help shed light on the nature of honesty and human preferences.’

The researchers’ study was published this week in the journal Nature Neuroscience. Their findings suggest that the “honesty switch” is likely located in the dorsolateral prefrontal cortex, located behind the forehead.

From the study’s abstract:

“We found that lesions of the human dorsolateral prefrontal cortex (DLPFC) decreased the effect of honesty concerns on behavior in economic games that pit honesty motives against self-interest, but did not affect decisions when honesty concerns were absent. These results point to a causal role for DLPFC in honest behavior.”

You’ll notice in the paragraph above the researchers don’t say “this is what controls lies” but rather explain how subjects with damaged DLPFCs exhibit fewer honest inhibitions, mostly due to a reduced concern for their self image. This is because the chosen experiment sought not to assess whether the DLPFC is active when telling a lie (other studies had suspected so much), but whether the DLPFC controls the decision to act honestly or not. The researchers found that most people strive to tell the truth; those with damaged DLPFCs made less of an effort.

Take a look at the Science Daily article linked below to learn more about the study, as well as what it means for further research. This may be a major step toward understanding the nature of honesty.