So what does that mean? It means that studies have shown that compulsive liars have up to 26% more white matter in their prefrontal cortex, so they’re better at making connections not grounded in reality. For example, for a practiced liar, it’s not a long stretch from “me” and “sexiest man alive.” As an expert liar, I’d believe that.
So when it comes to a lie, obviously if you watch tv, movies or work in law enforcement, you know about the polygraph machine; the lie detector. The machine works based on certain physiological cues – tremors, heart rate, all things controlled by the limbic system as a result of anxiety felt by the subject.
Therefore, a lie detector test can be fooled if a subject is unusually calm or anxious, and how much they deviate from their baseline. This means that the accuracy of a lie detector can be as low as 50% and as high as 90%, in variable conditions. Which makes the machine incredibly unreliable and inadmissible in court.