The more you lie, the easier it gets

 "Our brains are naturally better at telling the truth than lying, but repeated lying can overcome our tendency for veracity, making subsequent lying easier – and possibly undetectable.

Neuroimaging studies have shown that people's brains show considerably more activity when they are lying than when they are not, particularly in the prefrontal cortex, suggesting that lying requires extra cognitive control and inhibition of truth-telling. Lying also takes measurably longer than telling the truth."
via New Scientist/ continue reading