If you think telling a small lie now and then is harmless, think again. A new study published Monday in Nature Neuroscience found human brains become desensitized to the emotional discomfort caused by dishonesty, which makes telling big lies easier and more likely over time, STAT reported.
The study found small untruths easily "snowball over time," said study author Tali Sharot, PhD, director of the Affective Brain Lab and a faculty member of the department of the Experimental Psychology at University College London. This finding explains how small lies on tax returns can spiral into massive fraud or how scientific misconduct can balloon from "lost" data to fictional findings, according to the report.
The brain mechanism that causes the escalation of dishonesty is "emotional adaptation," according to Dr. Sharot and her colleagues. Telling a little lie might make one feel bad, but subsequent lies start to have less of a negative effect.
The study involved 80 volunteers between 18 and 65. Each was prompted to relay information via a computer to an unseen partner, who was actually one of the researchers. Volunteers could win money for relaying information to their partner, but they could win even more money for lying in some circumstances. In those cases the volunteers lied a little more with each round of the game, according to the report.
Twenty-five of the volunteers had an fMRI scan while they relayed the information to their unseen partner. The scans showed the amygdale, a part of the brain that processes unpleasant emotional experiences, was extremely active after the first self-serving lie. However, amygdala activity decreased before each subsequent lie, according to the report.
"The amygdala responded a lot the first times people lied, but it went down over time," said lead author Neil Garrett, PhD. "We think this is the first empirical evidence that lying escalates" as a result of emotional adaptation. This emphasizes "the potential danger of engaging in small acts of dishonesty on a regular basis," he added, according to the report.