Why Do Sensible People Believe Fake News?

You’re scrolling through Facebook, and you see that a friend has linked to an article; you glance at the title and realise that it’s nonsense. Or you’re chatting to a family member, and they share their opinion about politics; you discover they believe things that you’re sure aren’t true. In the information-filled world of today, it’s easy to come across fake news, propaganda, and rumours. But why is it passed on by people who seem otherwise sensible and intelligent?

It’s easy to assume that someone who believes fake news items must be lacking intelligence. It’s easy to say “Oh, that’s typical – that kind of person wouldn’t even question the lies they’re told.” It’s easy to think that other people aren’t as well-informed as you are. But when people you’ve known for years, whose opinions you’ve trusted in the past, begin to repeat nonsense, it’s not so easy to assume that they’re misinformed, credulous, or just plain stupid.

The answer has nothing to do with intelligence; it’s because the human brain is hardwired to help people live in communities. Scientists know that there are parts of the brain that help you to understand what other people are doing. Scans show that when you watch another person do something (e.g., lift a box down from a shelf), your brain responds as if you were doing that action. Brain cells called mirror neurons cause this reaction, and they’re essential to help you get on with other people.

For example, you’re standing next to someone in a supermarket who suddenly raises their hands above their head. Your mirror neurons fire when you see them move and your brain gets the message that “they’re doing the same movement that I do when I want to get a box from the top shelf.” If you didn’t have mirror neurons, you wouldn’t know whether that person was going to attack you, dance, or try climbing up the display unit. You’d spend your life being confused and anxious because you’d never understand other people’s actions.

Because it’s not a conscious process, a person isn’t aware this is happening. Nonetheless, the brain successfully makes hundreds of assessments every day about what other people intend. However, in the virtual world of 24-hour news, opinion, and social media, the brain starts to struggle. When the person sees that someone has liked a post on Facebook, their mirror neurons automatically send a message saying, “Hey, I understand what happened there; it’s just the same as when I like something.” It’s important to remember this isn’t a conscious decision. Nobody is constructing a rational argument in their head saying, “Well if Dave from work likes this, then I’m sure I’ll like it too.” It’s an immediate response: when they see another person liking something, the same parts of their brain become active as would be involved if they’d liked it themselves.

Once you know this, it’s easier to understand why otherwise sensible and rational people will believe something that isn’t true. Of course, there are echo chambers online; social media providers show users the kind of content that will keep them engaged. Studies have found that most people who retweet a link to a news article don’t click on it themselves; that makes it easier for trolls and bots to spread malicious content. Because seeing someone hit “like” has the same effect on your brain as if you had done so yourself, the fake news seems less threatening, less strange, and more believable.

That seems like bad news for truth and honesty, but there are reasons to be optimistic. Brain scans show that when test subjects are given specific instructions before they watch another person, different mirror neurons become active. In other words, if you get extra information, then the mirror neurons in your head don’t match what the other person is doing. That suggests that if you’re prepared to be critical of things you see shared online, then even if you see other people liking them, your brain won’t act as though you do.

It can be mystifying when people you know and respect believe things that aren’t true, at least until you learn about the way mirror neurons work. Although their primary function is to help people understand each other, they make the brain act to match what other people are doing. That is why seeing someone like or favourite or retweet something is so powerful, and why otherwise thoughtful, intelligent people can get fooled so easily.