Lying Repetitively Linked to Decreased Amygdala Activity

As people continue to tell tall tales, fMRI data show certain brain regions become less busy.

Oct 25, 2016
Kerry Grens

WIKIMEDIA, MEMORYLOSSONLINEScientists have observed changes in the human brain as study participants tell lies—specifically, as white lies became outright deception, the amygdalas of the fibbing volunteers became less active. The researchers’ findings, published in Nature Neuroscience yesterday (October 24), offer a possible neural mechanism for a common human failing, that lying can lead to more extensive dishonesty.  

“The reduction in activity in the amygdala can predict how much people increase dishonesty subsequently,” study coauthor Neil Garrett, a psychologist at University College London, told The Verge.

Garrett and colleagues asked 25 volunteers who saw a big image of a jar of pennies to give others (who only saw a small picture of the jar) estimates about the number of pennies. The volunteers were given incentives to lie, and after they had fibbed previously, fMRI data showed reduced activity in the amygdala when people were dishonest again. This brain region is involved in processing emotions.

“It’s an intriguing possibility that adaptation of amygdala response might underlie escalation in self-serving dishonesty,” Tom Johnstone, a neuroscientist at the University of Reading who was not involved in the study, told Scientific American, “though the results need to be replicated in a larger sample of participants, in order to examine the involvement of the many other brain regions previously shown to play a role in generating and regulating emotional responses.”