With the rise of President Trump, the term “fake news” has become increasingly common—a term he often uses to describe CNN. Although this term has become increasingly common, people have always wondered if they can trust what they watch and hear on television. You might think that technology might help us decide if something in the news is true. After all, we could check on Google, or check a number of different news outlets to see if they are all reporting the same story. But you might be wrong: attempting to verify a news story may actually make fake news influence you even more.

Why? What we know about memory

Many people think memory works likes a video camera. We experience events and information, and then later replay those events and information when we need it. But years of memory research show this idea is false. Memory is a constructive process—we remember details of an original event, but we might also incorporate other, incorrect, details into our memories. Say, for example, you were trying to remember your 21st birthday party. You might remember who was there and how you felt—perhaps how much you had to drink. But then, you might erroneously incorporate details from your 18th birthday party, for example, you remember having a barbecue. What you are left with is a memory that sort of resembles the true event, but is not completely accurate.

So why is our memory so constructive? One reason is that our memories, thoughts, and daydreams don’t come with specific tags. In other words, our memories aren’t stored in a mental filing cabinet. Instead, our memories are chaotic—we use feelings of what we remember to judge when and where that memory came from. Returning to my above example, when I recall my 21st birthday, I don’t have a dedicated section in my brain called “21st birthday party,” but when I search my memory for this party, I’ll start recalling parties that were attended by a lot of people. I might also recall times when people gave speeches about me. Obviously, some of these details I bring to mind will, indeed, be from my 21st birthday party, but others might be from similar events—like my 18th birthday party.

How does all of this relate to fake news?

Well, not having a mental filing cabinet can influence us in a number of ways. I might hear a story about Barrack Obama being born in Kenya. At the time, I might have thought that was crazy and untrue. But as time goes by, our memories lose context and we increasingly rely on how familiar something is as an indicator of truth. In this example, maybe a year later, my friend might say “Do you think President Obama was born in Kenya?” What information will I use to answer that question? If I can recall that I thought the news story was crazy, I might say “No.” If I can’t remember the news story well, but it sounds familiar, I’m might say something like “Yeah, I heard about that. It was on the news.”

It turns out we rely on familiarity a lot. For example, research shows that statements that are familiar are judged as being more likely to be true than statements that are not familiar. We like people and faces that are familiar too. The dangerous part is that familiarity can be increased simply through repetition. That is, if you hear something a number of times, you are more likely to think it is true than something you have heard once. So, if you are attempting to verify if a story in the news is true, you might watch a number of different news outlets. You might even say to yourself “This story must not be true.” But over time, and without repeatedly recalling the story, you may be left with a familiar feeling about the story. Later on, that familiar feeling can make you think the story is true.

Fake news and media outlets

What could news outlets take away from this research? We know that familiarity can be dangerous, so maybe instead of presenting a story and tagging it as fake, the media could choose not to present the story at all. After all, the media is supposed to report the news, so why do they need to report things that are false? Of course, the news outlets might not know if a story is true or false, and this research tells us that even a correction may not undo the damage of reporting fake news in the first place. So, perhaps, the media should wait until there is enough evidence before reporting. But this strategy is unlikely to be adopted because every media outlet wants to be the first to break a big story.

There is also a sinister possibility. Perhaps news outlets intentionally report fake news because they know it sticks. In other words, fake news might be a tactic that news outlets employ to sway public opinion. For example, Fox news might be more likely to report a story about President Obama being born in Kenya, whereas CNN might be more likely to report something false about President Trump. This possibility is highly plausible, but also very concerning. The purpose of the news should be to inform people, not to mislead them.

It may be that fake news is actually changing our expectations and definitions of news. Now, when we watch a specific news channel, we expect them to present biased, and potentially false, information. At the same time, these news outlets present stories with a sense of credibility and authority. For example, the presenters are well-dressed, there is official music, and fancy graphics. It’s not surprising, then, that there are so many people who believe things that are completely false.

How do we deal with fake news?

What can we do? We can realize when we are relying on familiarity to judge if something is true. It’s easy to detect: you won’t be able to recall when and where you learned about a certain piece of information, but you will have a feeling—almost like déjà vu—that you have encountered this information before. When you get that feeling, you need to check if this story is indeed true.

We also shouldn’t let media outlets off the hook if we know they are reporting fake news. The news shouldn’t be about politics and who the media outlet likes or dislikes. Instead, the news should be about presenting objective facts. But if we let these media outlets off the hook, we may see an increase in fake news. Perhaps there is some merit in President Trump’s war on the media?