We're living in the era of fake news. Not only was "fake news" the word of the year in 2017, but widespread lies and misinformation in the news – whether they're about climate change, immigrants or health care – still dominate headlines.

And the trend shows no signs of stopping.

So it's safe to say we all know "fake news" exists, right? But why does it actually work? Turns out, fake news taps into our brains in unique ways – and if you're primed to believe fake news, you can be hooked by even the most out-there lies. Here's how it works, and how you can protect yourself.

While the term "fake news" is still pretty new, the concept behind it is not. Propaganda – which is selectively misleading information designed to intentionally convey a certain point – has been around since, well, basically forever.

Propaganda was used by playwrights in ancient Greece, for instance, to further political and religious beliefs. And it's almost always used during wartime. Check out these inspiring, heroic-themed posters designed to help enlist troops during WWII.

Older propaganda feels so obvious it's almost silly. But, today, propaganda can take on more subtle forms. Take climate change deniers, for example. While earlier denialists claimed that global warming just flat out didn't exist, denialists today usually claim that there's still a question of whether human behavior is driving climate change.

In truth, there's a 97% percent consensus that climate change exists, and 18 scientific associations agree it's driven largely by humans. But climate change deniers cling to that remaining 3%, and spread propaganda about why climate change isn't real. By excluding important misinformation – focusing on the 3% of scientists who deny climate change instead of the 97% who don't – climate science denial propaganda is designed to mislead.

Finally, propaganda can involve simply suppressing dissenting voices. That's one tactic used by the Trump administration on climate change – to the point that a group of fired Environmental Protection Agency staffers just released their own environmental report after being silenced on the job.

Most of the time, propaganda works by tapping into existing fears and emotions to mislead you.

Some experts believe propaganda works because people want it to. Think about it – when you see a story that already aligns with your beliefs, you're less likely to question it. You might even feel comforted, because now you have even more evidence to support your existing beliefs. Chances are, it'd never occur to you to check if it's true, because it already feels "right."

But there's a deeper psychological process going on, too. See, your brain has an "executive control network" – regions of your brain responsible for higher-level functioning, like thinking analytically. Research shows that fear – including fear of immigrants, fear of foreign countries or fear of people unlike you – can suppress that executive control network.

In other words, fear makes it harder for your brain to think critically, so it's harder to spot false information – and you're more vulnerable to propaganda.

Just because propaganda is everywhere doesn't mean you need to fall for it. Take these steps to protect yourself (and those around you).

1. Question your fears. Since many forms of propaganda rely on fear to work, take time to question your own worries. If you're worried about an influx of immigrants to the country, ask yourself why. Seek out stories from people with different life experiences to learn more about them – you may find you have a lot in common!
2. Read the news critically. Any person or outlet could be spreading propaganda, so read the news with your "executive control network" activated. Check that news stories are citing credible sources – like peer-reviewed studies or respected organizations – and look at whether the story truly presents both sides. 
3. Understand how technology fuels propaganda. Advances in technology have made it possible to fake audio as well as doctor photos and video. While you may not be able to detect this kind of manipulation all the time, simply knowing it exists could protect you from thinking faked media is iron-clad "proof."