Your Brain Gives Up When Discerning Truth From Lies Gets Too Hard

By
Image
Photo: Dan Kitwood/Getty Images

You can call it “post-truth,” you can call it “fake news,” or you can, as Kellyanne Conway helpfully suggested on Meet the Press over the weekend, call it “alternative facts.” Or you can borrow Dan Rather’s phrasing from earlier this year: “A lie, is a lie, is a lie.” In a fantastic recent piece for Politico, psychology writer Maria Konnikova investigates 20 years’ worth of research on what happens when your brain is overloaded with a constant stream of untruths, and comes to a bleak forecast for the next four years. In short: Sorting fact from fiction can become so exhausting that, after a while, your brain simply stops trying.

Upon first hearing a lie, your brain must accept it as truth. Harvard psychologist Daniel Gilbert has theorized that to do the work of separating truth and lies, our brains first must accept the false statement as if it were true; otherwise, it’s impossible to engage with it. “For instance, if someone were to tell us — hypothetically, of course — that there had been serious voter fraud in Virginia during the presidential election, we must for a fraction of a second accept that fraud did, in fact, take place,” Konnikova explains. “Only then do we take the second step, either completing the mental certification process (yes, fraud!) or rejecting it (what? no way).”

If you hear a lie often enough, it starts to sound true. According to what’s called the “illusory truth effect,” the more you hear a false statement, the truer it starts to sound. This is even true when you should know better. In a fascinating, if disheartening, 2015 study, researchers showed that if people repeated the phrase “The Atlantic Ocean is the largest ocean on Earth” enough times, the Atlantic Ocean did indeed begin to seem like the largest ocean on Earth.

A constant stream of lies becomes so mentally taxing that your brain gives up. “It’s called cognitive load,” Konnikova writes, meaning that “our limited cognitive resources are overburdened.” Lie detection is difficult work, and your brain can only handle so much.

Your Brain Finds Liars Exhausting